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Sample records for counterpart search experiment

  1. Observations of the optical counterpart to XTE J1118+480 during outburst by the robotic optical transient search experiment In telescope

    CERN Document Server

    Wren, J; Balsano, R; Bloch, J; Borozdin, K N; Casperson, D E; Gisler, G; Kehoe, R; Lee Byung Cheol; Marshall, S; McKay, T; Priedhorsky, W; Rykoff, E S; Smith, D; Trudolyubov, S P; Vestrand, W T

    2001-01-01

    The X-ray nova XTE J1118+480 exhibited two outbursts in the early part of 2000. As detected by the Rossi X-ray Timing Explorer (RXTE), the first outburst began in early January and the second began in early March. Routine imaging of the northern sky by the Robotic Optical Transient Search Experiment (ROTSE) shows the optical counterpart to XTE J1118+480 during both outbursts. These data include over 60 epochs from January to June 2000. A search of the ROTSE data archives reveal no previous optical outbursts of this source in selected data between April 1998 and January 2000. While the X-ray to optical flux ratio of XTE J1118+480 was low during both outbursts, we suggest that they were full X-ray novae and not mini-outbursts based on comparison with similar sources. The ROTSE measurements taken during the March 2000 outburst also indicate a rapid rise in the optical flux that preceded the X-ray emission measured by the RXTE by approximately 10 days. Using these results, we estimate a pre-outburst accretion dis...

  2. A Search for X-ray Counterparts of Radio Pulsars

    CERN Document Server

    Prinz, Tobias

    2015-01-01

    We describe a systematic search for X-ray counterparts of radio pulsars. The search was accomplished by cross-correlating the radio timing positions of all radio pulsars from the ATNF pulsar database (version 1.54) with archival XMM-Newton and Chandra observations publicly released by August 1st 2015. In total, 171 of the archival XMM-Newton observations and 215 of the archival Chandra datasets where found to have a radio pulsar serendipitously in the field of view. From the 283 radio pulsars covered by these datasets we identified 19 previously undetected X-ray counterparts. For 6 of them the statistics was sufficient to model the energy spectrum with one- or two-component models. For the remaining new detections and for those pulsars for which we determined an upper limit to their counting rate we computed the energy flux by assuming a Crab-like spectrum. Additionally, we derived upper limits on the neutron stars' surface temperature and on the non-thermal X-ray efficiency for those pulsars for which the sp...

  3. The $X(3872)$ and the search for its bottomonium counterpart at the LHC

    CERN Document Server

    Toms, Konstantin; The ATLAS collaboration

    2016-01-01

    We present results on $X(3872)$ particle studies at three LHC experiments: ATLAS, CMS, and LHCb. Production cross section measurements are reported, as well as determination of the $X(3872)$ quantum numbers. The search of the $X(3872)$ bottomonium counterpart is also described.

  4. A search for VHE counterparts of galactic Fermi sources

    CERN Document Server

    Tam, P H Thomas; Tibolla, Omar; Chaves, Ryan

    2010-01-01

    Very high-energy (VHE; E > 100 GeV) gamma-rays have been detected from a wide range of astronomical objects, such as SNRs, pulsars and pulsar wind nebulae, AGN, gamma-ray binaries, molecular clouds, and possibly star-forming regions as well. At lower energies, sources detected using Large Area Telescope (LAT) aboard Fermi provide a rich set of data which can be used to study the behavior of cosmic accelerators in the GeV to TeV energy bands. In particular, the improved angular resolution in both bands compared to previous instruments significantly reduces source confusion and facilitates the identification of associated counterparts at lower energies. In this talk, a comprehensive search for VHE gamma-ray sources which are spatially coincident with Galactic Fermi/LAT bright sources is performed, and the GeV to TeV spectra of selected coincident sources are shown. It is found that LAT bright GeV sources are correlated to TeV sources, in contrast with previous studies using EGRET data.

  5. X(3872) and the search for its bottomonium counterpart at the LHC

    CERN Document Server

    Toms, Konstantin; The ATLAS collaboration

    2016-01-01

    X(3872) history and theoretical status overview. ATLAS study of the ψ(2S) and X(3872) production. Search for X(3872) bottomonium counterpart by ATLAS. Search for Xb at CMS. Determination of X(3872) quantum numbers at LHCb.

  6. Searching for Optical Counterparts to Ultra-compact High Velocity Clouds: Possible Detection of a Counterpart to AGC 198606

    CERN Document Server

    Janesh, William; Salzer, John J; Janowiecki, Steven; Adams, Elizabeth A K; Haynes, Martha P; Giovanelli, Riccardo; Cannon, John M; Muñoz, Ricardo R

    2015-01-01

    We report on initial results from a campaign to obtain optical imaging of a sample of Ultra Compact High Velocity Clouds (UCHVCs) discovered by the ALFALFA neutral hydrogen (HI) survey. UCHVCs are sources with velocities and sizes consistent with their being low-mass dwarf galaxies in the Local Volume, but without optical counterparts in existing catalogs. We are using the WIYN 3.5-m telescope and pODI camera to image these objects and search for an associated stellar population. In this paper, we present our observational strategy and method for searching for resolved stellar counterparts to the UCHVCs. We combine careful photometric measurements, a color-magnitude filter, and spatial smoothing techniques to search for stellar overdensities in the g- and i-band images. We also run statistical tests to quantify the likelihood that whatever overdensities we find are real and not chance superpositions of sources. We demonstrate the method by applying it to two data sets: WIYN imaging of Leo P, a UCHVC discovere...

  7. Searching for electromagnetic counterparts of gravitational wave transients

    CERN Document Server

    Branchesi, M; Laas-Bourez, M

    2011-01-01

    A pioneering electromagnetic (EM) observation follow-up program of candidate gravitational wave (GW) triggers has been performed, Dec 17 2009 to Jan 8 2010 and Sep 4 to Oct 20 2010, during the recent LIGO/Virgo run. The follow-up program involved ground-based and space EM facilities observing the sky at optical, X-ray and radio wavelengths. The joint GW/EM observation study requires the development of specific image analysis procedures able to discriminate the possible EM counterpart of GW trigger from background events. The paper shows an overview of the EM follow-up program and the developing image analysis procedures as they are applied to data collected with TAROT and Zadko.

  8. SEARCH FOR THE OPTICAL COUNTERPART TO SGR 0418+5729

    Energy Technology Data Exchange (ETDEWEB)

    Durant, Martin; Kargaltsev, Oleg [Department of Astronomy, University of Florida, FL 32611-2055 (United States); Pavlov, George G., E-mail: martin.durant@astro.ufl.edu [Department of Astronomy and Astrophysics, Pennsylvania State University, PA 16802 (United States)

    2011-12-01

    We report broadband Hubble Space Telescope imaging of the field of soft {gamma}-ray repeater SGR 0418+5729 with Advanced Camera for Surveys/Wide Field Channel and Wide Field Camera 3/IR. Observing in two wide filters, F606W and F110W, we find no counterpart within the positional error circle derived from Chandra observations, to limiting magnitudes m{sub F606W} > 28.6 and m{sub F110W} > 27.4 (Vega system), equivalent to reddening-corrected luminosity limits L{sub F606W} < 5 Multiplication-Sign 10{sup 28} and L{sub F110W} < 6 Multiplication-Sign 10{sup 28} erg s{sup -1} for a distance d = 2 kpc, at 3{sigma} confidence. This, in turn, imposes lower limits on the contemporaneous X-ray/optical flux ratio of {approx_equal}1100 and the X-ray/near-infrared flux ratio of {approx_equal}1000. We derive an upper limit on the temperature and/or size of any fall-back disk around the magnetar. We also compare the detection limits with observations of other magnetars.

  9. Galaxy Strategy for Ligo-Virgo Gravitational Wave Counterpart Searches

    Science.gov (United States)

    Gehrels, Neil; Cannizzo, John K.; Kanner, Jonah; Kasliwal, Mansi M.; Nissanke, Samaya; Singer, Leo P.

    2016-01-01

    In this work we continue a line of inquiry begun in Kanner et al. which detailed a strategy for utilizing telescopes with narrow fields of view, such as the Swift X-Ray Telescope (XRT), to localize gravity wave (GW) triggers from LIGO (Laser Interferometer Gravitational-Wave Observatory) / Virgo. If one considers the brightest galaxies that produce 50 percent of the light, then the number of galaxies inside typical GW error boxes will be several tens. We have found that this result applies both in the early years of Advanced LIGO when the range is small and the error boxes large, and in the later years when the error boxes will be small and the range large. This strategy has the beneficial property of reducing the number of telescope pointings by a factor 10 to 100 compared with tiling the entire error box. Additional galaxy count reduction will come from a GW rapid distance estimate which will restrict the radial slice in search volume. Combining the bright galaxy strategy with a convolution based on anticipated GW localizations, we find that the searches can be restricted to about 18 plus or minus 5 galaxies for 2015, about 23 plus or minus 4 for 2017, and about 11 plus or minus for 2020. This assumes a distance localization at the putative neutron star-neutron star (NS-NS) merger range mu for each target year, and these totals are integrated out to the range. Integrating out to the horizon would roughly double the totals. For localizations with r (rotation) greatly less than mu the totals would decrease. The galaxy strategy we present in this work will enable numerous sensitive optical and X-ray telescopes with small fields of view to participate meaningfully in searches wherein the prospects for rapidly fading afterglow place a premium on a fast response time.

  10. Galaxy Strategy for LIGO-Virgo Gravitational Wave Counterpart Searches

    CERN Document Server

    Gehrels, Neil; Kanner, Jonah; Kasliwal, Mansi M; Nissanke, Samaya; Singer, Leo P

    2015-01-01

    In this work we continue a line of inquiry begun in Kanner et al. which detailed a strategy for utilizing telescopes with narrow fields of view, such as the Swift X-ray Telescope (XRT), to localize gravity wave (GW) triggers from LIGO/Virgo. If one considers the brightest galaxies that produce ~50% of the light, then the number of galaxies inside typical GW error boxes will be several tens. We have found that this result applies both in the early years of Advanced LIGO when the range is small and the error boxes large, and in the later years when the error boxes will be small and the range large. This strategy has the beneficial property of reducing the number of telescope pointings by a factor 10 to 100 compared with tiling the entire error box. Additional galaxy count reduction will come from a GW rapid distance estimate which will restrict the radial slice in search volume. Combining the bright galaxy strategy with a convolution based on anticipated GW localizations, we find that the searches can be restri...

  11. A systematic search for near-infrared counterparts of nearby ultraluminous X-ray sources (II)

    Science.gov (United States)

    López, K. M.; Heida, M.; Jonker, P. G.; Torres, M. A. P.; Roberts, T. P.; Walton, D. J.; Moon, D.-S.; Harrison, F. A.

    2017-07-01

    We present the results of our continued systematic search for near-infrared (NIR) candidate counterparts to ultraluminous X-ray sources (ULXs) within 10 Mpc. We observed 42 ULXs in 24 nearby galaxies and detected NIR candidate counterparts to 15 ULXs. Fourteen of these ULXs appear to have a single candidate counterpart in our images and the remaining ULX has two candidate counterparts. Seven ULXs have candidate counterparts with absolute magnitudes in the range between -9.26 and -11.18 mag, consistent with them being red supergiants (RSGs). The other eight ULXs have candidate counterparts with absolute magnitudes too bright to be a single stellar source. Some of these NIR sources show extended morphology or colours expected for active galactic nuclei (AGNs), strongly suggesting that they are likely stellar clusters or background galaxies. The RSG candidate counterparts form a valuable sample for follow-up spectroscopic observations to confirm their nature, with the ultimate goal of directly measuring the mass of the compact accretor that powers the ULX using binary Doppler shifts.

  12. Searches for Optical Counterparts to Fermi Unassociated Sources with the Intermediate Palomar Transient Factory

    Science.gov (United States)

    Bellm, Eric Christopher; Prince, Thomas A.; Kaplan, David L. A.; Kupfer, Thomas; DeCesar, Megan E.; Laher, Russ; Masci, Frank J.; Shupe, David L.; Intermediate Palomar Transient Factory Collaboration

    2017-01-01

    The Intermediate Palomar Transient Factory (iPTF) has accumulated an extensive optical variability dataset across the Northern Sky, including at low Galactic latitudes (|b| < 20 degrees). We are using this dataset to search for optical counterparts to unassociated Fermi gamma-ray sources, particular the companions of eclipsing binary millisecond pulsars. So-called redback binary millisecond pulsars are a key evolutionary stage in the recycling process that spins up millisecond pulsars. The Roche-distorted and irradiated pulsar companion produces a periodic signature at the orbital period that may be readily identified with iPTF. We report on the progress of this search and present interesting candidates found.

  13. A Comprehensive Archival Search for Counterparts to Ultra-Compact High Velocity Clouds: Five Local Volume Dwarf Galaxies

    CERN Document Server

    Sand, D J; Bennet, P; Willman, B; Hargis, J; Strader, J; Olszewski, E; Tollerud, E J; Simon, J D; Caldwell, N; Guhathakurta, P; James, B L; Koposov, S; McLeod, B; Morrell, N; Peacock, M; Salinas, R; Seth, A C; Stark, D P; Toloba, E

    2015-01-01

    We report the discovery of five Local Volume dwarf galaxies uncovered during a comprehensive archival search for optical counterparts to ultra-compact high velocity clouds (UCHVCs). The UCHVC population of HI clouds are thought to be candidate gas-rich, low mass halos at the edge of the Local Group and beyond, but no comprehensive search for stellar counterparts to these systems has been presented. Careful visual inspection of all publicly available optical and ultraviolet imaging at the position of the UCHVCs revealed six blue, diffuse counterparts with a morphology consistent with a faint dwarf galaxy beyond the Local Group. Optical spectroscopy of all six candidate dwarf counterparts show that five have an H$\\alpha$-derived velocity consistent with the coincident HI cloud, confirming their association; the sixth diffuse counterpart is likely a background object. The size and luminosity of the UCHVC dwarfs is consistent with other known Local Volume dwarf irregular galaxies. The gas fraction ($M_{HI}/M_{sta...

  14. Multiwavelength search for counterparts of supersoft X-ray sources in M31

    CERN Document Server

    Chiosi, E; Bernardini, F; Henze, M; Jamialiahmadi, N

    2014-01-01

    We searched optical/UV/IR counterparts of seven supersoft X-ray sources (SSS) in M31 in the Hubble Space Telescope (HST) "Panchromatic Hubble Andromeda Treasury" (PHAT) archival images and photometric catalog. Three of the SSS were transient, the other four are persistent sources. The PHAT offers the opportunity to identify SSS hosting very massive white dwarfs that may explode as type Ia supernovae in single degenerate binaries, with magnitudes and color indexes typical of symbiotic stars, high mass close binaries, or systems with optically luminous accretion disks. We find evidence that the transient SSS were classical or recurrent novae; two likely counterparts we identified are probably symbiotic binaries undergoing mass transfer at a very high rate. There is a candidate accreting white dwarf binary in the error circle of one of the persistent sources, r3-8. In the spatial error circle of the best studied SSS in M31, r2-12, no red giants or AGB stars are sufficiently luminous in the optical and UV bands t...

  15. A Search for an Optical Counterpart to the Gravitational-wave Event GW151226

    Science.gov (United States)

    Smartt, S. J.; Chambers, K. C.; Smith, K. W.; Huber, M. E.; Young, D. R.; Chen, T.-W.; Inserra, C.; Wright, D. E.; Coughlin, M.; Denneau, L.; Flewelling, H.; Heinze, A.; Jerkstrand, A.; Magnier, E. A.; Maguire, K.; Mueller, B.; Rest, A.; Sherstyuk, A.; Stalder, B.; Schultz, A. S. B.; Stubbs, C. W.; Tonry, J.; Waters, C.; Wainscoat, R. J.; Della Valle, M.; Dennefeld, M.; Dimitriadis, G.; Firth, R. E.; Fraser, M.; Frohmaier, C.; Gal-Yam, A.; Harmanen, J.; Kankare, E.; Kotak, R.; Kromer, M.; Mandel, I.; Sollerman, J.; Gibson, B.; Primak, N.; Willman, M.

    2016-08-01

    We present a search for an electromagnetic counterpart of the gravitational-wave source GW151226. Using the Pan-STARRS1 telescope we mapped out 290 square degrees in the optical i P1 filter, starting 11.5 hr after the LIGO information release and lasting for an additional 28 days. The first observations started 49.5 hr after the time of the GW151226 detection. We typically reached sensitivity limits of i P1 = 20.3-20.8 and covered 26.5% of the LIGO probability skymap. We supplemented this with ATLAS survey data, reaching 31% of the probability region to shallower depths of m ≃ 19. We found 49 extragalactic transients (that are not obviously active galactic nuclei), including a faint transient in a galaxy at 7 Mpc (a luminous blue variable outburst) plus a rapidly decaying M-dwarf flare. Spectral classification of 20 other transient events showed them all to be supernovae. We found an unusual transient, PS15dpn, with an explosion date temporally coincident with GW151226, that evolved into a type Ibn supernova. The redshift of the transient is secure at z = 0.1747 ± 0.0001 and we find it unlikely to be linked, since the luminosity distance has a negligible probability of being consistent with that of GW151226. In the 290 square degrees surveyed we therefore do not find a likely counterpart. However we show that our survey strategy would be sensitive to NS-NS mergers producing kilonovae at D L ≲ 100 Mpc, which is promising for future LIGO/Virgo searches.

  16. Results from GROCSE, A Real-Time Search for the Optical Counterparts of Gamma-Ray Bursts

    Science.gov (United States)

    Akerlof, Carl; Lee, Brian; Barthelmy, Scott; Cline, Thomas; Gehrels, Neil; Ables, Elden; Bionta, Richard; Ott, Linda; Park, Hye-Sook; Fishman, Gerald; Kouveliotou, Chryssa; Meegan, Charles; Ferguson, Donald

    1994-12-01

    Since January 12, 1994, an experiment called GROCSE (Gamma-Ray Optical Counterpart Search Experiment) has been monitoring the night sky for the optical counterparts of gamma-ray bursts. The basic detector consists of an 8.9 cm aperture electronic camera attached to a rapid slewing computer-controlled mount. This device is activated by the real-time telemetry data stream from the BATSE instrument onboard the Compton Gamma-Ray Observatory. The BATSE signals are filtered and broadcast via the BACODINE network to Lawrence Livermore National Laboratory using the UNIX socket communication protocol linked via Internet. The typical response time to obtain the first image is approximately 15 seconds following the initial burst detection. The field of view of the camera is restricted to 0.18 sterdians to match the online angular position errors associated with the BACODINE GRB coordinate estimates. Under dark skys, the limiting detection magnitude is 8.5. By October 1994, the GROCSE camera has been triggered by seven BATSE bursts. Data from these events are being analyzed to provide either a detection or an upper limit for GRB optical luminosity. Results will be presented for the ratio of optical to gamma-ray intensity. A second generation camera system is currently under development that is expected to push the limiting magnitude to approximately m_v = 13. The status of this effort will be briefly reported.

  17. A search for optical counterparts of gamma-ray bursts. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hye-Sook

    1995-03-09

    Gamma Ray Bursts (GRBS) are mysterious flashes of gamma rays lasting several tens to hundreds of seconds that occur approximately once per day. NASA launched the orbiting Compton Gamma Ray Observatory to study GRBs and other gamma ray phenomena. CGRO carries the Burst and Transient Experiment (BATSE) specifically to study GRBS. Although BATSE has collected data on over 600 GRBS, and confirmed that GRBs are localized, high intensity point sources of MeV gamma rays distributed isotropically in the sky, the nature and origin of GRBs remains a fundamental problem in astrophysics. BATSE`s 8 gamma ray sensors located on the comers of the box shaped CGRO can detect the onset of GRBs and record their intensity and energy spectra as a function of time. The position of the burst on the sky can be determined to < {plus_minus}10{degrees} from the BATSE data stream. This position resolution is not sufficient to point a large, optical telescope at the exact position of a GRB which would determine its origin by associating it with a star. Because of their brief duration it is not known if GRBs are accompanied by visible radiation. Their seemingly large energy output suggests thatthis should be. Simply scaling the ratio of visible to gamma ray intensities of the Crab Nebula to the GRB output suggests that GRBs ought to be accompanied by visible flashes of magnitude 10 or so. A few photographs of areas containing a burst location that were coincidentally taken during the burst yield lower limits on visible output of magnitude 4. The detection of visible light during the GRB would provide information on burst physics, provide improved pointing coordinates for precise examination of the field by large telescope and provide the justification for larger dedicated optical counterpart instruments. The purpose of this experiment is to detect or set lower limits on optical counterpart radiation simultaneously accompanying the gamma rays from

  18. iPTF Search for an Optical Counterpart to Gravitational Wave Trigger GW150914

    CERN Document Server

    Kasliwal, M M; Singer, L P; Corsi, A; Cao, Y; Barlow, T; Bhalerao, V; Bellm, E; Cook, D; Duggan, G E; Ferretti, R; Frail, D A; Horesh, A; Kendrick, R; Kulkarni, S R; Lunnan, R; Palliyaguru, N; Laher, R; Masci, F; Manulis, I; Miller, A A; Nugent, P E; Perley, D; Prince, T A; Rana, J; Rebbapragada, U; Sesar, B; Singhal, A; Surace, J; Van Sistine, A

    2016-01-01

    The intermediate Palomar Transient Factory (iPTF) autonomously responded to and promptly tiled the error region of the first gravitational wave event GW150914 to search for an optical counterpart. Only a small fraction of the total localized region was immediately visible in the Northern night sky, due both to sun-angle and elevation constraints. Here, we report on the transient candidates identified and rapid follow-up undertaken to determine the nature of each candidate. Even in the small area imaged of 135 sq. deg., after extensive filtering, 8 candidates were deemed worthy of additional follow-up. Within two hours, all 8 were spectroscopically classified by the Keck II telescope. Curiously, even though such events are rare, one of our candidates was a superluminous supernova. We obtained radio data with the Very Large Array and X-ray follow-up with the Swift satellite for this transient. None of our candidates appear to be associated with the gravitational wave trigger, which is unsurprising given that GW...

  19. A DECam Search for an Optical Counterpart to the LIGO Gravitational Wave Event GW151226

    CERN Document Server

    Cowperthwaite, P S; Soares-Santos, M; Annis, J; Brout, D; Brown, D A; Buckley-Geer, E; Cenko, S B; Chen, H Y; Chornock, R; Diehl, H T; Doctor, Z; Drlica-Wagner, A; Drout, M R; Farr, B; Finley, D A; Foley, R J; Fong, W; Fox, D B; Frieman, J; Garcia-Bellido, J; Gill, M S S; Gruendl, R A; Herner, K; Holz, D E; Kasen, D; Kessler, R; Lin, H; Margutti, R; Marriner, J; Matheson, T; Metzger, B D; Neilsen, E H; Quataert, E; Rest, A; Sako, M; Scolnic, D; Smith, N; Sobreira, F; Strampelli, G M; Villar, V A; Walker, A R; Wester, W; Williams, P K G; Yanny, B; Abbott, T M C; Abdalla, F B; Allam, S; Armstrong, R; Bechtol, K; Benoit-Levy, A; Bertin, E; Brooks, D; Burke, D L; Rosell, A Carnero; Kind, M Carrasco; Carretero, J; Castander, F J; Cunha, C E; D'Andrea, C B; da Costa, L N; Desai, S; Dietrich, J P; Evrard, A E; Neto, A Fausti; Fosalba, P; Gerdes, D W; Giannantonio, T; Goldstein, D A; Gruen, D; Gutierrez, G; Honscheid, K; James, D J; Johnson, M W G; Johnson, M D; Krause, E; Kuehn, K; Kuropatkin, N; Lima, M; Maia, M A G; Marshall, J L; Menanteau, F; Miquel, R; Mohr, J J; Nichol, R C; Nord, B; Ogando, R; Plazas, A A; Reil, K; Romer, A K; Sanchez, E; Scarpine, V; Sevilla-Noarbe, I; Smith, R C; Suchyta, E; Tarle, G; Thomas, D; Thomas, R C; Tucker, D L; Weller, J

    2016-01-01

    We report the results of a Dark Energy Camera (DECam) optical follow-up of the gravitational wave (GW) event GW151226, discovered by the Advanced LIGO detectors. Our observations cover 28.8 deg$^2$ of the localization region in the $i$ and $z$ bands (containing 3% of the BAYESTAR localization probability), starting 10 hours after the event was announced and spanning four epochs at $2-24$ days after the GW detection. We achieve $5\\sigma$ point-source limiting magnitudes of $i\\approx21.7$ and $z\\approx21.5$, with a scatter of $0.4$ mag, in our difference images. Given the two day delay, we search this area for a rapidly declining optical counterpart with $\\gtrsim 3\\sigma$ significance steady decline between the first and final observations. We recover four sources that pass our selection criteria, of which three are cataloged AGN. The fourth source is offset by $5.8$ arcsec from the center of a galaxy at a distance of 187 Mpc, exhibits a rapid decline by $0.5$ mag over $4$ days, and has a red color of $i-z\\appr...

  20. A search for an optical counterpart to the gravitational wave event GW151226

    CERN Document Server

    Smartt, S J; Smith, K W; Huber, M E; Young, D R; Chen, T -W; Inserra, C; Wright, D E; Coughlin, M; Denneau, L; Flewelling, H; Heinze, A; Jerkstrand, A; Magnier, E A; Maguire, K; Mueller, B; Rest, A; Sherstyuk, A; Stalder, B; Schultz, A S B; Stubbs, C W; Tonry, J; Waters, C; Wainscoat, R; Della Valle, M; Dennefeld, M; Dimitriadis, G; Firth, R E; Fraser, M; Frohmaier, C; Gal-Yam, A; Harmanen, J; Kankare, E; Kotak, R; Kromer, M; Mandel, I; Sollerman, J; Gibson, B; Primak, N; Willman, M

    2016-01-01

    We present a search for an electromagnetic counterpart of the gravitational wave source GW151226. Using the Pan-STARRS1 telescope we mapped out 290 square degrees in the optical i_ps filter over a period starting 11.45hr after the LIGO information release (49.48hr after the GW trigger) and lasting for a further 28 days. We typically reached sensitivity limits of i_ps=20.3-20.8 and covered 26.5% of the LIGO probability skymap. We supplemented this with ATLAS survey data, reaching 31% of the probability region to shallower depths of m~19. We found 49 extragalactic transients (that are not obviously AGN), including a faint transient in a galaxy at 7Mpc (a luminous blue variable outburst) plus a rapidly decaying M-dwarf flare. Spectral classification of 20 other transient events showed them all to be supernovae. We found an unusual transient, PS15dpn, with an explosion date temporally coincident with GW151226 which evolved into a type Ibn supernova. The redshift of the transient is secure at z=0.1747 +/- 0.0001 a...

  1. First low-latency LIGO+Virgo search for binary inspirals and their electromagnetic counterparts

    Science.gov (United States)

    Abadie, J.; Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M.; Accadia, T.; Acernese, F.; Adams, C.; Adhikari, R.; Affeldt, C.; Agathos, M.; Agatsuma, K.; Ajith, P.; Allen, B.; Amador Ceron, E.; Amariutei, D.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Arain, M. A.; Araya, M. C.; Aston, S. M.; Astone, P.; Atkinson, D.; Aufmuth, P.; Aulbert, C.; Aylott, B. E.; Babak, S.; Baker, P.; Ballardin, G.; Ballmer, S.; Barayoga, J. C. B.; Barker, D.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barton, M. A.; Bartos, I.; Bassiri, R.; Bastarrika, M.; Basti, A.; Batch, J.; Bauchrowitz, J.; Bauer, Th. S.; Bebronne, M.; Beck, D.; Behnke, B.; Bejger, M.; Beker, M. G.; Bell, A. S.; Belletoile, A.; Belopolski, I.; Benacquista, M.; Berliner, J. M.; Bertolini, A.; Betzwieser, J.; Beveridge, N.; Beyersdorf, P. T.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Biswas, R.; Bitossi, M.; Bizouard, M. A.; Black, E.; Blackburn, J. K.; Blackburn, L.; Blair, D.; Bland, B.; Blom, M.; Bock, O.; Bodiya, T. P.; Bogan, C.; Bondarescu, R.; Bondu, F.; Bonelli, L.; Bonnand, R.; Bork, R.; Born, M.; Boschi, V.; Bose, S.; Bosi, L.; Bouhou, B.; Braccini, S.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Breyer, J.; Briant, T.; Bridges, D. O.; Brillet, A.; Brinkmann, M.; Brisson, V.; Britzger, M.; Brooks, A. F.; Brown, D. A.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Burguet-Castell, J.; Buskulic, D.; Buy, C.; Byer, R. L.; Cadonati, L.; Cagnoli, G.; Calloni, E.; Camp, J. B.; Campsie, P.; Cannizzo, J.; Cannon, K.; Canuel, B.; Cao, J.; Capano, C. D.; Carbognani, F.; Carbone, L.; Caride, S.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C.; Cesarini, E.; Chaibi, O.; Chalermsongsak, T.; Charlton, P.; Chassande-Mottin, E.; Chelkowski, S.; Chen, W.; Chen, X.; Chen, Y.; Chincarini, A.; Chiummo, A.; Cho, H. S.; Chow, J.; Christensen, N.; Chua, S. S. Y.; Chung, C. T. Y.; Chung, S.; Ciani, G.; Clara, F.; Clark, D. E.; Clark, J.; Clayton, J. H.; Cleva, F.; Coccia, E.; Cohadon, P.-F.; Colacino, C. N.; Colas, J.; Colla, A.; Colombini, M.; Conte, A.; Conte, R.; Cook, D.; Corbitt, T. R.; Cordier, M.; Cornish, N.; Corsi, A.; Costa, C. A.; Coughlin, M.; Coulon, J.-P.; Couvares, P.; Coward, D. M.; Cowart, M.; Coyne, D. C.; Creighton, J. D. E.; Creighton, T. D.; Cruise, A. M.; Cumming, A.; Cunningham, L.; Cuoco, E.; Cutler, R. M.; Dahl, K.; Danilishin, S. L.; Dannenberg, R.; D'Antonio, S.; Danzmann, K.; Dattilo, V.; Daudert, B.; Daveloza, H.; Davier, M.; Daw, E. J.; Day, R.; Dayanga, T.; De Rosa, R.; DeBra, D.; Debreczeni, G.; Del Pozzo, W.; del Prete, M.; Dent, T.; Dergachev, V.; DeRosa, R.; DeSalvo, R.; Dhurandhar, S.; Di Fiore, L.; Di Lieto, A.; Di Palma, I.; Emilio, M. Di Paolo; Di Virgilio, A.; Díaz, M.; Dietz, A.; Donovan, F.; Dooley, K. L.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Dumas, J.-C.; Dwyer, S.; Eberle, T.; Edgar, M.; Edwards, M.; Effler, A.; Ehrens, P.; Endrőczi, G.; Engel, R.; Etzel, T.; Evans, K.; Evans, M.; Evans, T.; Factourovich, M.; Fafone, V.; Fairhurst, S.; Fan, Y.; Farr, B. F.; Fazi, D.; Fehrmann, H.; Feldbaum, D.; Feroz, F.; Ferrante, I.; Fidecaro, F.; Finn, L. S.; Fiori, I.; Fisher, R. P.; Flaminio, R.; Flanigan, M.; Foley, S.; Forsi, E.; Forte, L. A.; Fotopoulos, N.; Fournier, J.-D.; Franc, J.; Frasca, S.; Frasconi, F.; Frede, M.; Frei, M.; Frei, Z.; Freise, A.; Frey, R.; Fricke, T. T.; Friedrich, D.; Fritschel, P.; Frolov, V. V.; Fujimoto, M.-K.; Fulda, P. J.; Fyffe, M.; Gair, J.; Galimberti, M.; Gammaitoni, L.; Garcia, J.; Garufi, F.; Gáspár, M. E.; Gemme, G.; Geng, R.; Genin, E.; Gennai, A.; Gergely, L. Á.; Ghosh, S.; Giaime, J. A.; Giampanis, S.; Giardina, K. D.; Giazotto, A.; Gil-Casanova, S.; Gill, C.; Gleason, J.; Goetz, E.; Goggin, L. M.; González, G.; Gorodetsky, M. L.; Goßler, S.; Gouaty, R.; Graef, C.; Graff, P. B.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Gray, N.; Greenhalgh, R. J. S.; Gretarsson, A. M.; Greverie, C.; Grosso, R.; Grote, H.; Grunewald, S.; Guidi, G. M.; Guido, C.; Gupta, R.; Gustafson, E. K.; Gustafson, R.; Ha, T.; Hallam, J. M.; Hammer, D.; Hammond, G.; Hanks, J.; Hanna, C.; Hanson, J.; Harms, J.; Harry, G. M.; Harry, I. W.; Harstad, E. D.; Hartman, M. T.; Haughian, K.; Hayama, K.; Hayau, J.-F.; Heefner, J.; Heidmann, A.; Heintze, M. C.; Heitmann, H.; Hello, P.; Hendry, M. A.; Heng, I. S.; Heptonstall, A. W.; Herrera, V.; Hewitson, M.; Hild, S.; Hoak, D.; Hodge, K. A.; Holt, K.; Holtrop, M.; Hong, T.; Hooper, S.; Hosken, D. J.; Hough, J.; Howell, E. J.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Ingram, D. R.; Inta, R.; Isogai, T.; Ivanov, A.; Izumi, K.; Jacobson, M.; James, E.; Jang, Y. J.; Jaranowski, P.; Jesse, E.; Johnson, W. W.; Jones, D. I.; Jones, G.; Jones, R.; Ju, L.; Kalmus, P.; Kalogera, V.; Kandhasamy, S.

    2012-05-01

    Aims: The detection and measurement of gravitational-waves from coalescing neutron-star binary systems is an important science goal for ground-based gravitational-wave detectors. In addition to emitting gravitational-waves at frequencies that span the most sensitive bands of the LIGO and Virgo detectors, these sources are also amongst the most likely to produce an electromagnetic counterpart to the gravitational-wave emission. A joint detection of the gravitational-wave and electromagnetic signals would provide a powerful new probe for astronomy. Methods: During the period between September 19 and October 20, 2010, the first low-latency search for gravitational-waves from binary inspirals in LIGO and Virgo data was conducted. The resulting triggers were sent to electromagnetic observatories for followup. We describe the generation and processing of the low-latency gravitational-wave triggers. The results of the electromagnetic image analysis will be described elsewhere. Results: Over the course of the science run, three gravitational-wave triggers passed all of the low-latency selection cuts. Of these, one was followed up by several of our observational partners. Analysis of the gravitational-wave data leads to an estimated false alarm rate of once every 6.4 days, falling far short of the requirement for a detection based solely on gravitational-wave data.

  2. A DECam Search for an Optical Counterpart to the LIGO Gravitational-wave Event GW151226

    Science.gov (United States)

    Cowperthwaite, P. S.; Berger, E.; Soares-Santos, M.; Annis, J.; Brout, D.; Brown, D. A.; Buckley-Geer, E.; Cenko, S. B.; Chen, H. Y.; Chornock, R.; Diehl, H. T.; Doctor, Z.; Drlica-Wagner, A.; Drout, M. R.; Farr, B.; Finley, D. A.; Foley, R. J.; Fong, W.; Fox, D. B.; Frieman, J.; Garcia-Bellido, J.; Gill, M. S. S.; Gruendl, R. A.; Herner, K.; Holz, D. E.; Kasen, D.; Kessler, R.; Lin, H.; Margutti, R.; Marriner, J.; Matheson, T.; Metzger, B. D.; Neilsen, E. H., Jr.; Quataert, E.; Rest, A.; Sako, M.; Scolnic, D.; Smith, N.; Sobreira, F.; Strampelli, G. M.; Villar, V. A.; Walker, A. R.; Wester, W.; Williams, P. K. G.; Yanny, B.; Abbott, T. M. C.; Abdalla, F. B.; Allam, S.; Armstrong, R.; Bechtol, K.; Benoit-Lévy, A.; Bertin, E.; Brooks, D.; Burke, D. L.; Carnero Rosell, A.; Carrasco Kind, M.; Carretero, J.; Castander, F. J.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; Desai, S.; Dietrich, J. P.; Evrard, A. E.; Fausti Neto, A.; Fosalba, P.; Gerdes, D. W.; Giannantonio, T.; Goldstein, D. A.; Gruen, D.; Gutierrez, G.; Honscheid, K.; James, D. J.; Johnson, M. W. G.; Johnson, M. D.; Krause, E.; Kuehn, K.; Kuropatkin, N.; Lima, M.; Maia, M. A. G.; Marshall, J. L.; Menanteau, F.; Miquel, R.; Mohr, J. J.; Nichol, R. C.; Nord, B.; Ogando, R.; Plazas, A. A.; Reil, K.; Romer, A. K.; Sanchez, E.; Scarpine, V.; Sevilla-Noarbe, I.; Smith, R. C.; Suchyta, E.; Tarle, G.; Thomas, D.; Thomas, R. C.; Tucker, D. L.; Weller, J.; DES Collaboration

    2016-08-01

    We report the results of a Dark Energy Camera optical follow-up of the gravitational-wave (GW) event GW151226, discovered by the Advanced Laser Interferometer Gravitational-wave Observatory detectors. Our observations cover 28.8 deg2 of the localization region in the i and z bands (containing 3% of the BAYESTAR localization probability), starting 10 hr after the event was announced and spanning four epochs at 2-24 days after the GW detection. We achieve 5σ point-source limiting magnitudes of i≈ 21.7 and z≈ 21.5, with a scatter of 0.4 mag, in our difference images. Given the two-day delay, we search this area for a rapidly declining optical counterpart with ≳ 3σ significance steady decline between the first and final observations. We recover four sources that pass our selection criteria, of which three are cataloged active galactic nuclei. The fourth source is offset by 5.8 arcsec from the center of a galaxy at a distance of 187 Mpc, exhibits a rapid decline by 0.5 mag over 4 days, and has a red color of i-z≈ 0.3 mag. These properties could satisfy a set of cuts designed to identify kilonovae. However, this source was detected several times, starting 94 days prior to GW151226, in the Pan-STARRS Survey for Transients (dubbed as PS15cdi) and is therefore unrelated to the GW event. Given its long-term behavior, PS15cdi is likely a Type IIP supernova that transitioned out of its plateau phase during our observations, mimicking a kilonova-like behavior. We comment on the implications of this detection for contamination in future optical follow-up observations.

  3. A search for counterparts to massive X-ray binaries using photometric catalogues

    CERN Document Server

    Negueruela, I; Negueruela, Ignacio; Schurch, Matthew

    2006-01-01

    (abridged) INTEGRAL has discovered large numbers of new hard X-ray sources, many of which are believed to be high mass X-ray binaries. However, for a significant fraction, their counterparts remain unidentified. We explore the use of photometric catalogues to find optical counterparts to high mass X-ray binaries. Candidates were selected from 2MASS photometry by means of a reddening free Q parameter. Sufficiently bright candidates were spectroscopically observed. Many of the candidates selected turned out to be moderately reddened late A or early F stars, but our method is able to identify the counterpart to IGR J16207-5129, confirmed by a Chandra localisation. We classify this object as a B0 supergiant. In the field of AX J1820.5-1434, we find a mid or early B-type star, but we cannot confirm it as the counterpart. For AX J1700.2-4220, we do not find any suitable candidate within the ASCA error circle. We classify HD 153295, a marginal candidate to be the counterpart, as B0.5IVe, and find a distance compatib...

  4. The Pan-STARRS, Mauna Kea, and PESSTO search for optical counterparts to aLIGO gravitational wave events

    Science.gov (United States)

    Chambers, Kenneth C.; Pan-STARRS Collaboration

    2016-06-01

    We have searched for an optical counterpart to the first gravitational wave source discovered by the Advanced LIGO experiment, GW150914, using the Pan-STARRS wide-field telescope and associated data processing to identify transient objects. Interesting candidates are then followed up using the UH88, Gemini, and PESSTO for the spectroscopic characterization. We mapped out 442 square degrees of the northern sky region of the initial LIGO map. We discovered 56 astrophysical transients over a period of 41 days from the discovery of the source. Of these, 19 were spectroscopically classied and a further 13 have host galaxy redshifts. All transients appear to be fairly normal supernovae and AGN variability and none are obviously linked with GW150914. We find one high energey type II supernova with an estimated explosion date consistent with that of GW150914, but no causal link can be inferred. We discuss our results as demonstration of the survey capability of Pan-STARRS, and the spectroscopic capabilities of PESSTO and Mauna Kea.

  5. Pan-STARRS and PESSTO search for the optical counterpart to the LIGO gravitational wave source GW150914

    CERN Document Server

    Smartt, S J; Smith, K W; Huber, M E; Young, D R; Cappellaro, E; Wright, D E; Coughlin, M; Schultz, A S B; Denneau, L; Flewelling, H; Heinze, A; Magnier, E A; Primak, N; Rest, A; Sherstyuk, A; Stalder, B; Stubbs, C W; Tonry, J; Waters, C; Willman, M; Anderson, J P; Baltay, C; Botticella, M T; Campbell, H; Dennefeld, M; Chen, T -W; Della Valle, M; Elias-Rosa, N; Fraser, M; Inserra, C; Kankare, E; Kotak, R; Kupfer, T; Harmanen, J; Galbany, L; Gal-Yam, A; Guillou, L L; Lyman, J D; Maguire, K; Mitra, A; Nicholl, M; E, F Olivares; Rabinowitz, D; Razza, A; Sollerman, J; Smith, M; Terreran, G; Valenti, S

    2016-01-01

    We have searched for an optical counterpart to the first gravitational wave source discovered by the LIGO experiment, GW150914, using a combination of the Pan-STARRS1 wide-field telescope and the PESSTO spectroscopic follow-up programme. We mapped out 442 square degrees of the northern sky region of the initial map. We discovered 56 astrophysical transients over a period of 41 days from the discovery of the source. Of these, 19 were spectroscopically classified and a further 13 have host galaxy redshifts. All transients appear to be fairly normal supernovae and AGN variability and none is obviously linked with GW150914. We find one high energy type II supernova with an estimated explosion date consistent with that of GW150914, but no causal link can be inferred. We quantify the upper limits by defining parameterised lightcurves with timescales of 4, 20 and 40 days and use the sensitivity of the Pan-STARRS1 images to set limits on the luminosities of possible sources. The Pan-STARRS1 images reach limiting magn...

  6. Search of MeV-GeV counterparts of TeV sources with AGILE in pointing mode

    Science.gov (United States)

    Rappoldi, A.; Lucarelli, F.; Pittori, C.; Longo, F.; Cattaneo, P. W.; Verrecchia, F.; Tavani, M.; Bulgarelli, A.; Chen, A. W.; Colafrancesco, S.; Donnarumma, I.; Giuliani, A.; Morselli, A.; Sabatini, S.; Vercellone, S.

    2016-03-01

    Context. Known TeV sources detected by major Čerenkov telescopes are investigated to identify possible MeV-GeV γ-ray counterparts. Aims: A systematic study of the known sources in the web-based TeVCat catalog has been performed to search for possible γ-ray counterparts on the AGILE data collected during the first period of operations in observing pointing mode. Methods: For each TeV source, a search for a possible γ-ray counterpart that is based on a multi-source maximum likelihood algorithm is performed on the AGILE data taken with the GRID instrument from July 2007 to October 2009. Results: In the case of high-significance detection, the average γ-ray flux is estimated. For cases of low-significance detection the 95% confidence level (CL) flux upper limit is given. 52 TeV sources out of 152 (corresponding to ~34% of the analysed sample) show a significant excess in the AGILE data covering the pointing observation period. Conclusions: This analysis found 26 new AGILE sources with respect to the AGILE reference catalogs, 15 of which are galactic, 7 are extragalactic and 4 are unidentified. Detailed tables with all available information on the analysed sources are presented. An interactive online version of the considered source list including all the analysis results is also available at the website http://www.asdc.asi.it/agiletevcat/

  7. A Dark Energy Camera Search for an Optical Counterpart to the First Advanced LIGO Gravitational Wave Event GW150914

    Energy Technology Data Exchange (ETDEWEB)

    Soares-Santos, M. [et al.

    2016-05-27

    We report initial results of a deep search for an optical counterpart to the gravitational wave event GW150914, the first trigger from the Advanced LIGO gravitational wave detectors. We used the Dark Energy Camera (DECam) to image a 102 deg$^2$ area, corresponding to 38% of the initial trigger high-probability sky region and to 11% of the revised high-probability region. We observed in i and z bands at 4-5, 7, and 24 days after the trigger. The median $5\\sigma$ point-source limiting magnitudes of our search images are i=22.5 and z=21.8 mag. We processed the images through a difference-imaging pipeline using templates from pre-existing Dark Energy Survey data and publicly available DECam data. Due to missing template observations and other losses, our effective search area subtends 40 deg$^{2}$, corresponding to 12% total probability in the initial map and 3% of the final map. In this area, we search for objects that decline significantly between days 4-5 and day 7, and are undetectable by day 24, finding none to typical magnitude limits of i= 21.5,21.1,20.1 for object colors (i-z)=1,0,-1, respectively. Our search demonstrates the feasibility of a dedicated search program with DECam and bodes well for future research in this emerging field.

  8. A Dark Energy Camera Search for an Optical Counterpart to the First Advanced LIGO Gravitational Wave Event GW150914

    CERN Document Server

    Soares-Santos, M; Berger, E; Annis, J; Brout, D; Buckley-Geer, E; Chen, H; Cowperthwaite, P S; Diehl, H T; Doctor, Z; Drlica-Wagner, A; Farr, B; Finley, D A; Flaugher, B; Foley, R; Frieman, J; Gruendl, R A; Herner, K; Holz, D; Lin, H; Marriner, J; Neilsen, E; Rest, A; Sako, M; Scolnic, D; Sobreira, F; Walker, A R; Wester, W; Yanny, B; Abbott, T M C; Abdalla, F B; Allam, S; Armstrong, R; Banerji, M; Benoit-Lévy, A; Bernstein, R A; Bertin, E; Brown, D A; Burke, D L; Capozzi, D; Rosell, A Carnero; Kind, M Carrasco; Carretero, J; Castander, F J; Cenko, S B; Chornock, R; Crocce, M; D'Andrea, C B; da Costa, L N; Desai, S; Dietrich, J P; Drout, M R; Eifler, T F; Estrada, J; Evrard, A E; Fairhurst, S; Fernandez, E; Fischer, J; Fong, W; Fosalba, P; Fox, D B; Fryer, C L; Garcia-Bellido, J; Gaztanaga, E; Gerdes, D W; Goldstein, D A; Gruen, D; Gutierrez, G; Honscheid, K; James, D J; Karliner, I; Kasen, D; Kent, S; Kuropatkin, N; Kuehn, K; Lahav, O; Li, T S; Lima, M; Maia, M A G; Margutti, R; Martini, P; Matheson, T; McMahon, R G; Metzger, B D; Miller, C J; Miquel, R; Mohr, J J; Nichol, R C; Nord, B; Ogando, R; Peoples, J; Plazas, A A; Quataert, E; Romer, A K; Roodman, A; Rykoff, E S; Sanchez, E; Scarpine, V; Schindler, R; Schubnell, M; Sevilla-Noarbe, I; Sheldon, E; Smith, M; Smith, N; Smith, R C; Stebbins, A; Sutton, P J; Swanson, M E C; Tarle, G; Thaler, J; Thomas, R C; Tucker, D L; Vikram, V; Wechsler, R H; Weller, J

    2016-01-01

    We report initial results of a deep search for an optical counterpart to the gravitational wave event GW150914, the first trigger from the Advanced LIGO gravitational wave detectors. We used the Dark Energy Camera (DECam) to image a 102 deg$^2$ area, corresponding to 38% of the initial trigger high-probability sky region and to 11% of the revised high-probability region. We observed in i and z bands at 4-5, 7, and 24 days after the trigger. The median $5\\sigma$ point-source limiting magnitudes of our search images are i=22.5 and z=21.8 mag. We processed the images through a difference-imaging pipeline using templates from pre-existing Dark Energy Survey data and publicly available DECam data. Due to missing template observations and other losses, our effective search area subtends 40 deg$^{2}$, corresponding to 12% total probability in the initial map and 3% of the final map. In this area, we search for objects that decline significantly between days 4-5 and day 7, and are undetectable by day 24, finding none...

  9. First Searches for Optical Counterparts to Gravitational-wave Candidate Events

    CERN Document Server

    Aasi, J; Abbott, B P; Abbott, R; Abbott, T; Abernathy, M R; Accadia, T; Acernese, F; Adams, C; Adams, T; Adhikari, R X; Affeldt, C; Agathos, M; Aggarwal, N; Aguiar, O D; Ajith, P; Allen, B; Allocca, A; Ceron, E Amador; Amariutei, D; Anderson, R A; Anderson, S B; Anderson, W G; Arai, K; Araya, M C; Arceneaux, C; Areeda, J; Ast, S; Aston, S M; Astone, P; Aufmuth, P; Aulbert, C; Austin, L; Aylott, B E; Babak, S; Baker, P T; Ballardin, G; Ballmer, S W; Barayoga, J C; Barker, D; Barnum, S H; Barone, F; Barr, B; Barsotti, L; Barsuglia, M; Barton, M A; Bartos, I; Bassiri, R; Basti, A; Batch, J; Bauchrowitz, J; Bauer, Th S; Bebronne, M; Behnke, B; Bejger, M; Beker, M G; Bell, A S; Bell, C; Belopolski, I; Bergmann, G; Berliner, J M; Bertolini, A; Bessis, D; Betzwieser, J; Beyersdorf, P T; Bhadbhade, T; Bilenko, I A; Billingsley, G; Birch, J; Bitossi, M; Bizouard, M A; Black, E; Blackburn, J K; Blackburn, L; Blair, D; Blom, M; Bock, O; Bodiya, T P; Boer, M; Bogan, C; Bond, C; Bondu, F; Bonelli, L; Bonnand, R; Bork, R; Born, M; Bose, S; Bosi, L; Bowers, J; Bradaschia, C; Brady, P R; Braginsky, V B; Branchesi, M; Brannen, C A; Brau, J E; Breyer, J; Briant, T; Bridges, D O; Brillet, A; Brinkmann, M; Brisson, V; Britzger, M; Brooks, A F; Brown, D A; Brown, D D; Brückner, F; Bulik, T; Bulten, H J; Buonanno, A; Buskulic, D; Buy, C; Byer, R L; Cadonati, L; Cagnoli, G; Bustillo, J Calderón; Calloni, E; Camp, J B; Campsie, P; Cannon, K C; Canuel, B; Cao, J; Capano, C D; Carbognani, F; Carbone, L; Caride, S; Castiglia, A; Caudill, S; Cavaglià, M; Cavalier, F; Cavalieri, R; Cella, G; Cepeda, C; Cesarini, E; Chakraborty, R; Chalermsongsak, T; Chao, S; Charlton, P; Chassande-Mottin, E; Chen, X; Chen, Y; Chincarini, A; Chiummo, A; Cho, H S; Chow, J; Christensen, N; Chu, Q; Chua, S S Y; Chung, S; Ciani, G; Clara, F; Clark, D E; Clark, J A; Cleva, F; Coccia, E; Cohadon, P -F; Colla, A; Colombini, M; Constancio, M; Conte, A; Conte, R; Cook, D; Corbitt, T R; Cordier, M; Cornish, N; Corsi, A; Costa, C A; Coughlin, M W; Coulon, J -P; Countryman, S; Couvares, P; Coward, D M; Cowart, M; Coyne, D C; Craig, K; Creighton, J D E; Creighton, T D; Crowder, S G; Cumming, A; Cunningham, L; Cuoco, E; Dahl, K; Canton, T Dal; Damjanic, M; Danilishin, S L; D'Antonio, S; Danzmann, K; Dattilo, V; Daudert, B; Daveloza, H; Davier, M; Davies, G S; Daw, E J; Day, R; Dayanga, T; De Rosa, R; Debreczeni, G; Degallaix, J; Del Pozzo, W; Deleeuw, E; Deléglise, S; Denker, T; Dereli, H; Dergachev, V; DeRosa, R; DeSalvo, R; Dhurandhar, S; Di Fiore, L; Di Lieto, A; Di Palma, I; Di Virgilio, A; D'\\iaz, M; Dietz, A; Dmitry, K; Donovan, F; Dooley, K L; Doravari, S; Drago, M; Drever, R W P; Driggers, J C; Du, Z; Dumas, J -C; Dwyer, S; Eberle, T; Edwards, M; Effler, A; Ehrens, P; Eichholz, J; Eikenberry, S S; Endrőczi, G; Essick, R; Etzel, T; Evans, K; Evans, M; Evans, T; Factourovich, M; Fafone, V; Fairhurst, S; Fang, Q; Farr, B; Farr, W; Favata, M; Fazi, D; Fehrmann, H; Feldbaum, D; Ferrante, I; Ferrini, F; Fidecaro, F; Finn, L S; Fiori, I; Fisher, R; Flaminio, R; Foley, E; Foley, S; Forsi, E; Forte, L A; Fotopoulos, N; Fournier, J -D; Franco, S; Frasca, S; Frasconi, F; Frede, M; Frei, M; Frei, Z; Freise, A; Frey, R; Fricke, T T; Fritschel, P; Frolov, V V; Fujimoto, M -K; Fulda, P; Fyffe, M; Gair, J; Gammaitoni, L; Garcia, J; Garufi, F; Gehrels, N; Gemme, G; Genin, E; Gennai, A; Gergely, L; Ghosh, S; Giaime, J A; Giampanis, S; Giardina, K D; Giazotto, A; Gil-Casanova, S; Gill, C; Gleason, J; Goetz, E; Goetz, R; Gondan, L; González, G; Gordon, N; Gorodetsky, M L; Gossan, S; Goßler, S; Gouaty, R; Graef, C; Graff, P B; Granata, M; Grant, A; Gras, S; Gray, C; Greenhalgh, R J S; Gretarsson, A M; Griffo, C; Grote, H; Grover, K; Grunewald, S; Guidi, G M; Guido, C; Gushwa, K E; Gustafson, E K; Gustafson, R; Hall, B; Hall, E; Hammer, D; Hammond, G; Hanke, M; Hanks, J; Hanna, C; Hanson, J; Harms, J; Harry, G M; Harry, I W; Harstad, E D; Hartman, M T; Haughian, K; Hayama, K; Heefner, J; Heidmann, A; Heintze, M; Heitmann, H; Hello, P; Hemming, G; Hendry, M; Heng, I S; Heptonstall, A W; Heurs, M; Hild, S; Hoak, D; Hodge, K A; Holt, K; Holtrop, M; Hong, T; Hooper, S; Horrom, T; Hosken, D J; Hough, J; Howell, E J; Hu, Y; Hua, Z; Huang, V; Huerta, E A; Hughey, B; Husa, S; Huttner, S H; Huynh, M; Huynh-Dinh, T; Iafrate, J; Ingram, D R; Inta, R; Isogai, T; Ivanov, A; Iyer, B R; Izumi, K; Jacobson, M; James, E; Jang, H; Jang, Y J; Jaranowski, P; Jiménez-Forteza, F; Johnson, W W; Jones, D; Jones, D I; Jones, R; Jonker, R J G; Ju, L; K, Haris; Kalmus, P; Kalogera, V; Kandhasamy, S; Kang, G; Kanner, J B; Kasprzack, M; Kasturi, R; Katsavounidis, E; Katzman, W; Kaufer, H; Kaufman, K; Kawabe, K; Kawamura, S; Kawazoe, F; Kéfélian, F; Keitel, D; Kelley, D B; Kells, W; Keppel, D G; Khalaidovski, A; Khalili, F Y; Khazanov, E A; Kim, B K; Kim, C; Kim, K; Kim, N; Kim, W; Kim, Y -M; King, E J; King, P J; Kinzel, D L; Kissel, J S; Klimenko, S; Kline, J; Koehlenbeck, S; Kokeyama, K; Kondrashov, V; Koranda, S; Korth, W Z; Kowalska, I; Kozak, D; Kremin, A; Kringel, V; Krishnan, B; Królak, A; Kucharczyk, C; Kudla, S; Kuehn, G; Kumar, A; Kumar, P; Kumar, R; Kurdyumov, R; Kwee, P; Landry, M; Lantz, B; Larson, S; Lasky, P D; Lawrie, C; Lazzarini, A; Roux, A Le; Leaci, P; Lebigot, E O; Lee, C -H; Lee, H K; Lee, H M; Lee, J; Leonardi, M; Leong, J R; Leroy, N; Letendre, N; Levine, B; Lewis, J B; Lhuillier, V; Li, T G F; Lin, A C; Littenberg, T B; Litvine, V; Liu, F; Liu, H; Liu, Y; Liu, Z; Lloyd, D; Lockerbie, N A; Lockett, V; Lodhia, D; Loew, K; Logue, J; Lombardi, A L; Lorenzini, M; Loriette, V; Lormand, M; Losurdo, G; Lough, J; Luan, J; Lubinski, M J; Lück, H; Lundgren, A P; Macarthur, J; Macdonald, E; Machenschalk, B; MacInnis, M; Macleod, D M; Magana-Sandoval, F; Mageswaran, M; Mailand, K; Majorana, E; Maksimovic, I; Malvezzi, V; Man, N; Manca, G M; Mandel, I; Mandic, V; Mangano, V; Mantovani, M; Marchesoni, F; Marion, F; Márka, S; Márka, Z; Markosyan, A; Maros, E; Marque, J; Martelli, F; Martin, I W; Martin, R M; Martinelli, L; Martynov, D; Marx, J N; Mason, K; Masserot, A; Massinger, T J; Matichard, F; Matone, L; Matzner, R A; Mavalvala, N; May, G; Mazumder, N; Mazzolo, G; McCarthy, R; McClelland, D E; McGuire, S C; McIntyre, G; McIver, J; Meacher, D; Meadors, G D; Mehmet, M; Meidam, J; Meier, T; Melatos, A; Mendell, G; Mercer, R A; Meshkov, S; Messenger, C; Meyer, M S; Miao, H; Michel, C; Mikhailov, E E; Milano, L; Miller, J; Minenkov, Y; Mingarelli, C M F; Mitra, S; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Moe, B; Mohan, M; Mohapatra, S R P; Mokler, F; Moraru, D; Moreno, G; Morgado, N; Mori, T; Morriss, S R; Mossavi, K; Mours, B; Mow-Lowry, C M; Mueller, C L; Mueller, G; Mukherjee, S; Mullavey, A; Munch, J; Murphy, D; Murray, P G; Mytidis, A; Nagy, M F; Kumar, D Nanda; Nardecchia, I; Nash, T; Naticchioni, L; Nayak, R; Necula, V; Neri, I; Newton, G; Nguyen, T; Nishida, E; Nishizawa, A; Nitz, A; Nocera, F; Nolting, D; Normandin, M E; Nuttall, L K; Ochsner, E; O'Dell, J; Oelker, E; Ogin, G H; Oh, J J; Oh, S H; Ohme, F; Oppermann, P; O'Reilly, B; Larcher, W Ortega; O'Shaughnessy, R; Osthelder, C; Ottaway, D J; Ottens, R S; Ou, J; Overmier, H; Owen, B J; Padilla, C; Pai, A; Palomba, C; Pan, Y; Pankow, C; Paoletti, F; Paoletti, R; Papa, M A; Paris, H; Pasqualetti, A; Passaquieti, R; Passuello, D; Pedraza, M; Peiris, P; Penn, S; Perreca, A; Phelps, M; Pichot, M; Pickenpack, M; Piergiovanni, F; Pierro, V; Pinard, L; Pindor, B; Pinto, I M; Pitkin, M; Poeld, J; Poggiani, R; Poole, V; Poux, C; Predoi, V; Prestegard, T; Price, L R; Prijatelj, M; Principe, M; Privitera, S; Prix, R; Prodi, G A; Prokhorov, L; Puncken, O; Punturo, M; Puppo, P; Quetschke, V; Quintero, E; Quitzow-James, R; Raab, F J; Rabeling, D S; Rácz, I; Radkins, H; Raffai, P; Raja, S; Rajalakshmi, G; Rakhmanov, M; Ramet, C; Rapagnani, P; Raymond, V; Re, V; Reed, C M; Reed, T; Regimbau, T; Reid, S; Reitze, D H; Ricci, F; Riesen, R; Riles, K; Robertson, N A; Robinet, F; Rocchi, A; Roddy, S; Rodriguez, C; Rodruck, M; Roever, C; Rolland, L; Rollins, J G; Romano, J D; Romano, R; Romanov, G; Romie, J H; Rosińska, D; Rowan, S; Rüdiger, A; Ruggi, P; Ryan, K; Salemi, F; Sammut, L; Sandberg, V; Sanders, J; Sannibale, V; Santiago-Prieto, I; Saracco, E; Sassolas, B; Sathyaprakash, B S; Saulson, P R; Savage, R; Schilling, R; Schnabel, R; Schofield, R M S; Schreiber, E; Schuette, D; Schulz, B; Schutz, B F; Schwinberg, P; Scott, J; Scott, S M; Seifert, F; Sellers, D; Sengupta, A S; Sentenac, D; Sergeev, A; Shaddock, D; Shah, S; Shahriar, M S; Shaltev, M; Shapiro, B; Shawhan, P; Shoemaker, D H; Sidery, T L; Siellez, K; Siemens, X; Sigg, D; Simakov, D; Singer, A; Singer, L; Sintes, A M; Skelton, G R; Slagmolen, B J J; Slutsky, J; Smith, J R; Smith, M R; Smith, R J E; Smith-Lefebvre, N D; Soden, K; Son, E J; Sorazu, B; Souradeep, T; Sperandio, L; Staley, A; Steinert, E; Steinlechner, J; Steinlechner, S; Steplewski, S; Stevens, D; Stochino, A; Stone, R; Strain, K A; Strigin, S; Stroeer, A S; Sturani, R; Stuver, A L; Summerscales, T Z; Susmithan, S; Sutton, P J; Swinkels, B; Szeifert, G; Tacca, M; Talukder, D; Tang, L; Tanner, D B; Tarabrin, S P; Taylor, R; ter Braack, A P M; Thirugnanasambandam, M P; Thomas, M; Thomas, P; Thorne, K A; Thorne, K S; Thrane, E; Tiwari, V; Tokmakov, K V; Tomlinson, C; Toncelli, A; Tonelli, M; Torre, O; Torres, C V; Torrie, C I; Travasso, F; Traylor, G; Tse, M; Ugolini, D; Unnikrishnan, C S; Vahlbruch, H; Vajente, G; Vallisneri, M; Brand, J F J van den; Broeck, C Van Den; van der Putten, S; van der Sluys, M V; van Heijningen, J; van Veggel, A A; Vass, S; Vasúth, M; Vaulin, R; Vecchio, A; Vedovato, G; Veitch, J; Veitch, P J; Venkateswara, K; Verkindt, D; Verma, S; Vetrano, F; Viceré, A; Vincent-Finley, R; Vinet, J -Y; Vitale, S; Vlcek, B; Vo, T; Vocca, H; Vorvick, C; Vousden, W D; Vrinceanu, D; Vyachanin, S P; Wade, A; Wade, L; Wade, M; Waldman, S J; Walker, M; Wallace, L; Wan, Y; Wang, J; Wang, M; Wang, X; Wanner, A; Ward, R L; Was, M; Weaver, B; Wei, L -W; Weinert, M; Weinstein, A J; Weiss, R; Welborn, T; Wen, L; Wessels, P; West, M; Westphal, T; Wette, K; Whelan, J T; Whitcomb, S E; White, D J; Whiting, B F; Wibowo, S; Wiesner, K; Wilkinson, C; Williams, L; Williams, R; Williams, T; Willis, J L; Willke, B; Wimmer, M; Winkelmann, L; Winkler, W; Wipf, C C; Wittel, H; Woan, G; Worden, J; Yablon, J; Yakushin, I; Yamamoto, H; Yancey, C C; Yang, H; Yeaton-Massey, D; Yoshida, S; Yum, H; Yvert, M; Zadrożny, A; Zanolin, M; Zendri, J -P; Zhang, F; Zhang, L; Zhao, C; Zhu, H; Zhu, X J; Zotov, N; Zucker, M E; Zweizig, J; Akerlof, C; Baltay, C; Bloom, J S; Cao, Y; Cenko, S B; Ćwiek, A; Ćwiok, M; Dhillon, V; Fox, D B; Gal-Yam, A; Kasliwal, M M; Klotz, A; Laas-Bourez, M; Laher, R R; Law, N M; Majcher, A; Małek, K; Mankiewicz, L; Nawrocki, K; Nissanke, S; Nugent, P E; Ofek, E O; Opiela, R; Piotrowski, L; Poznanski, D; Rabinowitz, D; Rapoport, S; Richards, J W; Schmidt, B; Siudek, M; Sokołowski, M; Steele, I A; Sullivan, M; Żarnecki, A F; Zheng, W

    2013-01-01

    During the LIGO and Virgo joint science runs in 2009-2010, gravitational wave (GW) data from three interferometer detectors were analyzed within minutes to select GW candidate events and infer their apparent sky positions. Target coordinates were transmitted to several telescopes for follow-up observations aimed at the detection of an associated optical transient. Images were obtained for eight such GW candidates. We present the methods used to analyze the image data as well as the transient search results. No optical transient was identified with a convincing association with any of these candidates, and none of the GW triggers showed strong evidence for being astrophysical in nature. We compare the sensitivities of these observations to several model light curves from possible sources of interest, and discuss prospects for future joint GW-optical observations of this type.

  10. FIRST SEARCHES FOR OPTICAL COUNTERPARTS TO GRAVITATIONAL-WAVE CANDIDATE EVENTS

    Energy Technology Data Exchange (ETDEWEB)

    Aasi, J.; Abadie, J.; Abbott, B. P.; Abbott, R.; Abernathy, M. R.; Adhikari, R. X.; Ajith, P. [LIGO - California Institute of Technology, Pasadena, CA 91125 (United States); Abbott, T. [Louisiana State University, Baton Rouge, LA 70803 (United States); Accadia, T. [Laboratoire d' Annecy-le-Vieux de Physique des Particules (LAPP), Université de Savoie, CNRS/IN2P3, F-74941 Annecy-le-Vieux (France); Acernese, F. [INFN, Sezione di Napoli, Complesso Universitario di Monte S. Angelo, I-80126 Napoli (Italy); Adams, C. [LIGO - Livingston Observatory, Livingston, LA 70754 (United States); Adams, T. [Cardiff University, Cardiff, CF24 3AA (United Kingdom); Affeldt, C.; Allen, B. [Albert-Einstein-Institut, Max-Planck-Institut für Gravitationsphysik, D-30167 Hannover (Germany); Agathos, M. [Nikhef, Science Park, 1098 XG Amsterdam (Netherlands); Aggarwal, N. [LIGO - Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Aguiar, O. D. [Instituto Nacional de Pesquisas Espaciais, 12227-010 - São José dos Campos, SP (Brazil); Allocca, A. [INFN, Sezione di Pisa, I-56127 Pisa (Italy); Amador Ceron, E. [University of Wisconsin-Milwaukee, Milwaukee, WI 53201 (United States); Amariutei, D. [University of Florida, Gainesville, FL 32611 (United States); Collaboration: LIGO Scientific Collaboration and the Virgo Collaboration; and others

    2014-03-01

    During the Laser Interferometer Gravitational-wave Observatory and Virgo joint science runs in 2009-2010, gravitational wave (GW) data from three interferometer detectors were analyzed within minutes to select GW candidate events and infer their apparent sky positions. Target coordinates were transmitted to several telescopes for follow-up observations aimed at the detection of an associated optical transient. Images were obtained for eight such GW candidates. We present the methods used to analyze the image data as well as the transient search results. No optical transient was identified with a convincing association with any of these candidates, and none of the GW triggers showed strong evidence for being astrophysical in nature. We compare the sensitivities of these observations to several model light curves from possible sources of interest, and discuss prospects for future joint GW-optical observations of this type.

  11. First Searches for Optical Counterparts to Gravitational-wave Candidate Events

    Science.gov (United States)

    Aasi, J.; Abadie, J.; Abbott, B. P.; Abbott, R.; Abbott, T.; Abernathy, M. R.; Accadia, T.; Acernese, F.; Adams, C.; Adams, T.; Adhikari, R. X.; Affeldt, C.; Agathos, M.; Aggarwal, N.; Aguiar, O. D.; Ajith, P.; Allen, B.; Allocca, A.; Amador Ceron, E.; Amariutei, D.; Anderson, R. A.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Araya, M. C.; Arceneaux, C.; Areeda, J.; Ast, S.; Aston, S. M.; Astone, P.; Aufmuth, P.; Aulbert, C.; Austin, L.; Aylott, B. E.; Babak, S.; Baker, P. T.; Ballardin, G.; Ballmer, S. W.; Barayoga, J. C.; Barker, D.; Barnum, S. H.; Barone, F.; Barr, B.; Barsotti, L.; Barsuglia, M.; Barton, M. A.; Bartos, I.; Bassiri, R.; Basti, A.; Batch, J.; Bauchrowitz, J.; Bauer, Th. S.; Bebronne, M.; Behnke, B.; Bejger, M.; Beker, M. G.; Bell, A. S.; Bell, C.; Belopolski, I.; Bergmann, G.; Berliner, J. M.; Bertolini, A.; Bessis, D.; Betzwieser, J.; Beyersdorf, P. T.; Bhadbhade, T.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Bitossi, M.; Bizouard, M. A.; Black, E.; Blackburn, J. K.; Blackburn, L.; Blair, D.; Blom, M.; Bock, O.; Bodiya, T. P.; Boer, M.; Bogan, C.; Bond, C.; Bondu, F.; Bonelli, L.; Bonnand, R.; Bork, R.; Born, M.; Bose, S.; Bosi, L.; Bowers, J.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brannen, C. A.; Brau, J. E.; Breyer, J.; Briant, T.; Bridges, D. O.; Brillet, A.; Brinkmann, M.; Brisson, V.; Britzger, M.; Brooks, A. F.; Brown, D. A.; Brown, D. D.; Brückner, F.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Buskulic, D.; Buy, C.; Byer, R. L.; Cadonati, L.; Cagnoli, G.; Calderón Bustillo, J.; Calloni, E.; Camp, J. B.; Campsie, P.; Cannon, K. C.; Canuel, B.; Cao, J.; Capano, C. D.; Carbognani, F.; Carbone, L.; Caride, S.; Castiglia, A.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C.; Cesarini, E.; Chakraborty, R.; Chalermsongsak, T.; Chao, S.; Charlton, P.; Chassande-Mottin, E.; Chen, X.; Chen, Y.; Chincarini, A.; Chiummo, A.; Cho, H. S.; Chow, J.; Christensen, N.; Chu, Q.; Chua, S. S. Y.; Chung, S.; Ciani, G.; Clara, F.; Clark, D. E.; Clark, J. A.; Cleva, F.; Coccia, E.; Cohadon, P.-F.; Colla, A.; Colombini, M.; Constancio, M., Jr.; Conte, A.; Conte, R.; Cook, D.; Corbitt, T. R.; Cordier, M.; Cornish, N.; Corsi, A.; Costa, C. A.; Coughlin, M. W.; Coulon, J.-P.; Countryman, S.; Couvares, P.; Coward, D. M.; Cowart, M.; Coyne, D. C.; Craig, K.; Creighton, J. D. E.; Creighton, T. D.; Crowder, S. G.; Cumming, A.; Cunningham, L.; Cuoco, E.; Dahl, K.; Dal Canton, T.; Damjanic, M.; Danilishin, S. L.; D'Antonio, S.; Danzmann, K.; Dattilo, V.; Daudert, B.; Daveloza, H.; Davier, M.; Davies, G. S.; Daw, E. J.; Day, R.; Dayanga, T.; De Rosa, R.; Debreczeni, G.; Degallaix, J.; Del Pozzo, W.; Deleeuw, E.; Deléglise, S.; Denker, T.; Dereli, H.; Dergachev, V.; DeRosa, R.; DeSalvo, R.; Dhurandhar, S.; Di Fiore, L.; Di Lieto, A.; Di Palma, I.; Di Virgilio, A.; Díaz, M.; Dietz, A.; Dmitry, K.; Donovan, F.; Dooley, K. L.; Doravari, S.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Dumas, J.-C.; Dwyer, S.; Eberle, T.; Edwards, M.; Effler, A.; Ehrens, P.; Eichholz, J.; Eikenberry, S. S.; Endrőczi, G.; Essick, R.; Etzel, T.; Evans, K.; Evans, M.; Evans, T.; Factourovich, M.; Fafone, V.; Fairhurst, S.; Fang, Q.; Farr, B.; Farr, W.; Favata, M.; Fazi, D.; Fehrmann, H.; Feldbaum, D.; Ferrante, I.; Ferrini, F.; Fidecaro, F.; Finn, L. S.; Fiori, I.; Fisher, R.; Flaminio, R.; Foley, E.; Foley, S.; Forsi, E.; Forte, L. A.; Fotopoulos, N.; Fournier, J.-D.; Franco, S.; Frasca, S.; Frasconi, F.; Frede, M.; Frei, M.; Frei, Z.; Freise, A.; Frey, R.; Fricke, T. T.; Fritschel, P.; Frolov, V. V.; Fujimoto, M.-K.; Fulda, P.; Fyffe, M.; Gair, J.; Gammaitoni, L.; Garcia, J.; Garufi, F.; Gehrels, N.; Gemme, G.; Genin, E.; Gennai, A.; Gergely, L.; Ghosh, S.; Giaime, J. A.; Giampanis, S.; Giardina, K. D.; Giazotto, A.; Gil-Casanova, S.; Gill, C.; Gleason, J.; Goetz, E.; Goetz, R.; Gondan, L.; González, G.; Gordon, N.; Gorodetsky, M. L.; Gossan, S.; Goßler, S.; Gouaty, R.; Graef, C.; Graff, P. B.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Greenhalgh, R. J. S.; Gretarsson, A. M.; Griffo, C.; Grote, H.; Grover, K.; Grunewald, S.; Guidi, G. M.; Guido, C.; Gushwa, K. E.; Gustafson, E. K.; Gustafson, R.; Hall, B.; Hall, E.; Hammer, D.; Hammond, G.; Hanke, M.; Hanks, J.; Hanna, C.; Hanson, J.; Harms, J.; Harry, G. M.; Harry, I. W.; Harstad, E. D.; Hartman, M. T.; Haughian, K.; Hayama, K.; Heefner, J.; Heidmann, A.; Heintze, M.; Heitmann, H.; Hello, P.; Hemming, G.; Hendry, M.; Heng, I. S.; Heptonstall, A. W.; Heurs, M.; Hild, S.; Hoak, D.; Hodge, K. A.; Holt, K.; Holtrop, M.; Hong, T.; Hooper, S.; Horrom, T.; Hosken, D. J.; Hough, J.; Howell, E. J.; Hu, Y.; Hua, Z.; Huang, V.; Huerta, E. A.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh, M.; Huynh-Dinh, T.; Iafrate, J.; Ingram, D. R.; Inta, R.

    2014-03-01

    During the Laser Interferometer Gravitational-wave Observatory and Virgo joint science runs in 2009-2010, gravitational wave (GW) data from three interferometer detectors were analyzed within minutes to select GW candidate events and infer their apparent sky positions. Target coordinates were transmitted to several telescopes for follow-up observations aimed at the detection of an associated optical transient. Images were obtained for eight such GW candidates. We present the methods used to analyze the image data as well as the transient search results. No optical transient was identified with a convincing association with any of these candidates, and none of the GW triggers showed strong evidence for being astrophysical in nature. We compare the sensitivities of these observations to several model light curves from possible sources of interest, and discuss prospects for future joint GW-optical observations of this type.

  12. First Searches for Optical Counterparts to Gravitational-Wave Candidate Events

    Science.gov (United States)

    Aasi, J.; Abadie, J.; Abbott, B. P.; Abbott, R.; Abbott, T.; Abernathy, M. R.; Accadia, T.; Acernese, F.; Adams, C.; Adams, T.; Adhikari, R. X.; Affeldt, C.; Agathos, M.; Aggarwal, N.; Aguiar, O. D.; Ajith, P.; Allen, B.; Allocca, A.; Amador Ceron, E.; Blackburn, L.; Camp, J. B.; Gehrels, N.; Graff, P. B.; Kanner, J. B.; Cenko, S. B.

    2014-01-01

    During the Laser Interferometer Gravitational-wave Observatory and Virgo joint science runs in 2009-2010, gravitational wave (GW) data from three interferometer detectors were analyzed within minutes to select GW candidate events and infer their apparent sky positions. Target coordinates were transmitted to several telescopes for follow-up observations aimed at the detection of an associated optical transient. Images were obtained for eight such GW candidates. We present the methods used to analyze the image data as well as the transient search results. No optical transient was identified with a convincing association with any of these candidates, and none of the GW triggers showed strong evidence for being astrophysical in nature. We compare the sensitivities of these observations to several model light curves from possible sources of interest, and discuss prospects for future joint GW-optical observations of this type.

  13. Searches for optical counterparts of BATSE gamma-ray bursts with the Explosive Transient Camera.

    Science.gov (United States)

    Krimm, H. A.; Vanderspek, R. K.; Ricker, G. R.

    1996-12-01

    The Explosive Transient Camera (ETC) is a wide-field CCD camera system capable of detecting short (1-10s) celestial optical flashes as faint as m~10 over a field-of-view of 0.75-steradians between -15° and +62° declination. The ETC has been operating automatically under computer control since January 1991. Since the launch of the Compton Gamma Ray Observatory, the ETC has been capable of observing an optical flash coincident with a gamma-ray burst (GRB) detected by the Burst and Transient Spectroscopy Experiment (BATSE). Between April 1991 and August 1995, there were seven cases of at least partial spatial overlap between a BATSE 68% confidence positional error box and the ETC field-of-view during an ETC observation. In each case upper limits are placed on the optical-to-gamma-ray flux ratio.

  14. Experiment data report for semiscale Mod-1 Test S-06-5. (LOFT counterpart test). [PWR

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-06-01

    Recorded test data are presented for Test S-06-5 of the Semiscale Mod-1 LOFT counterpart test series. These tests are among several Semiscale Mod-1 experiments conducted to investigate the thermal and hydraulic phenomena accompanying a hypothesized loss-of-coolant accident in a pressurized water reactor (PWR) system. Test S-06-5 was conducted from initial conditions of 2272 psia and 536/sup 0/F to investigate the response of the Semiscale Mod-1 system to a depressurization and reflood transient following a simulated double-ended offset shear of the broken loop cold leg piping. During the test, cooling water was injected into the cold legs of the intact and broken loops to simulate emergency core coolant injection in a PWR. The purpose of Test S-06-5 was to assess the influence of the break nozzle geometry on core thermal and system response and on the subcooled and low quality mass flow rates at the break locations.

  15. Pan-STARRS and PESSTO search for an optical counterpart to the LIGO gravitational-wave source GW150914

    Science.gov (United States)

    Smartt, S. J.; Chambers, K. C.; Smith, K. W.; Huber, M. E.; Young, D. R.; Cappellaro, E.; Wright, D. E.; Coughlin, M.; Schultz, A. S. B.; Denneau, L.; Flewelling, H.; Heinze, A.; Magnier, E. A.; Primak, N.; Rest, A.; Sherstyuk, A.; Stalder, B.; Stubbs, C. W.; Tonry, J.; Waters, C.; Willman, M.; Anderson, J. P.; Baltay, C.; Botticella, M. T.; Campbell, H.; Dennefeld, M.; Chen, T.-W.; Della Valle, M.; Elias-Rosa, N.; Fraser, M.; Inserra, C.; Kankare, E.; Kotak, R.; Kupfer, T.; Harmanen, J.; Galbany, L.; Gal-Yam, A.; Le Guillou, L.; Lyman, J. D.; Maguire, K.; Mitra, A.; Nicholl, M.; Olivares E, F.; Rabinowitz, D.; Razza, A.; Sollerman, J.; Smith, M.; Terreran, G.; Valenti, S.; Gibson, B.; Goggia, T.

    2016-11-01

    We searched for an optical counterpart to the first gravitational-wave source discovered by LIGO (GW150914), using a combination of the Pan-STARRS1 wide-field telescope and the Public ESO Spectroscopic Survey of Transient Objects (PESSTO) spectroscopic follow-up programme. As the final LIGO sky maps changed during analysis, the total probability of the source being spatially coincident with our fields was finally only 4.2 per cent. Therefore, we discuss our results primarily as a demonstration of the survey capability of Pan-STARRS and spectroscopic capability of PESSTO. We mapped out 442 deg2 of the northern sky region of the initial map. We discovered 56 astrophysical transients over a period of 41 d from the discovery of the source. Of these, 19 were spectroscopically classified and a further 13 have host galaxy redshifts. All transients appear to be fairly normal supernovae (SNe) and AGN variability and none is obviously linked with GW150914. We illustrate the sensitivity of our survey by defining parametrized light curves with time-scales of 4, 20 and 40 d and use the sensitivity of the Pan-STARRS1 images to set limits on the luminosities of possible sources. The Pan-STARRS1 images reach limiting magnitudes of iP1 = 19.2, 20.0 and 20.8, respectively, for the three time-scales. For long time-scale parametrized light curves (with full width half-maximum ≃40 d), we set upper limits of M_i ≤ -17.2^{-0.9}_{+1.4} if the distance to GW150914 is DL = 400 ± 200 Mpc. The number of Type Ia SN we find in the survey is similar to that expected from the cosmic SN rate, indicating a reasonably complete efficiency in recovering SN like transients out to DL = 400 ± 200 Mpc.

  16. GW150914: First search for the electromagnetic counterpart of a gravitational-wave event by the TOROS collaboration

    CERN Document Server

    Díaz, Mario C; Peñuela, Tania; Macri, Lucas M; Oelkers, Ryan J; Yuan, Wenlong; Lambas, Diego García; Cabral, Juan; Colazo, Carlos; Domínguez, Mariano; Sánchez, Bruno; Gurovich, Sebastián; Lares, Marcelo; Schneiter, Matías; Graña, Darío; Renzi, Victor; Rodriguez, Horacio; Starck, Manuel; Vrech, Rubén; Artola, Rodolfo; Ferreyra, Antonio Chiavassa; Girardini, Carla; Quiñones, Cecilia; Tapia, Luis; Tornatore, Marina; Marshall, Jennifer L; DePoy, Darren L; Branchesi, Marica; Brocato, Enzo; Padilla, Nelson; Pereyra, Nicolás A; Mukherjee, Soma; Benacquista, Matthew; Key, Joey

    2016-01-01

    We present the results of the optical follow-up conducted by the TOROS collaboration of the first gravitational-wave event GW150914. We conducted unfiltered CCD observations (0.35-1 micron) with the 1.5-m telescope at Bosque Alegre starting ~2.5 days after the alarm. Given our limited field of view (~100 square arcmin), we targeted 14 nearby galaxies that were observable from the site and were located within the area of higher localization probability. We analyzed the observations using two independent implementations of difference-imaging algorithms, followed by a Random-Forest-based algorithm to discriminate between real and bogus transients. We did not find any bona fide transient event in the surveyed area down to a 5-sigma limiting magnitude of r=21.7 mag (AB). Our result is consistent with the LIGO detection of a binary black hole merger, for which no electromagnetic counterparts are expected, and with the expected rates of other astrophysical transients.

  17. A blind search for prompt gamma-ray counterparts of fast radio bursts with Fermi-LAT data

    Science.gov (United States)

    Yamasaki, Shotaro; Totani, Tomonori; Kawanaka, Norita

    2016-08-01

    Fast radio bursts (FRBs) are a mysterious flash phenomenon detected in radio wavelengths with a duration of only a few milliseconds, and they may also have prompted gamma-ray flashes. Here, we carry out a blind search for ms-duration gamma-ray flashes using the 7-yr Fermi Large Area Telescope all-sky gamma-ray data. About 100 flash candidates are detected, but after removing those associated with bright steady point sources, we find no flash events at high Galactic latitude region (|b| > 20°). Events at lower latitude regions are consistent with statistical flukes originating from the diffuse gamma-ray background. From these results, we place an upper limit on the GeV gamma-ray to radio flux ratio of FRBs as ξ ≡ (νLν)γ/(νLν)radio ≲ (4.2-12) × 107, depending on the assumed FRB rate evolution index β = 0-4 [cosmic FRB rate ΦFRB ∝ (1 + z)β]. This limit is comparable with the largest value found for pulsars, though ξ of pulsars is distributed in a wide range. We also compare this limit with the spectral energy distribution of the 2004 giant flare of the magnetar SGR 1806-20.

  18. A Blind Search for Prompt Gamma-ray Counterparts of Fast Radio Bursts with Fermi-LAT Data

    CERN Document Server

    Yamasaki, Shotaro; Kawanaka, Norita

    2016-01-01

    Fast Radio Bursts (FRBs) are a mysterious flash phenomenon detected in radio wavelengths with a duration of only a few milliseconds, and they may also have prompt gamma-ray flashes. Here we carry out a blind search for msec-duration gamma-ray flashes using the 7-year Fermi Large Area Telescope (Fermi-LAT) all-sky gamma-ray data. About 100 flash candidates are detected, but after removing those associated with bright steady point sources, we find no flash events at high Galactic latitude region (|b|>20 deg). Events at lower latitude regions are consistent with statistical flukes originating from the diffuse gamma-ray background. From these results, we place an upper limit on the GeV gamma-ray to radio flux ratio of FRBs as xi \\equiv (nu L_nu)_gamma / (nu L_nu)_radio < 10^8, depending on the assumed FRB rate evolution. This limit is comparable with the largest value found for pulsars, though xi of pulsars is distributed in a wide range. We also compare this limit with the spectral energy distribution of the ...

  19. J-GEM follow-up observations to search for an optical counterpart of the first gravitational wave source GW150914

    Science.gov (United States)

    Morokuma, Tomoki; Tanaka, Masaomi; Asakura, Yuichiro; Abe, Fumio; Tristram, Paul J.; Utsumi, Yousuke; Doi, Mamoru; Fujisawa, Kenta; Itoh, Ryosuke; Itoh, Yoichi; Kawabata, Koji S.; Kawai, Nobuyuki; Kuroda, Daisuke; Matsubayashi, Kazuya; Motohara, Kentaro; Murata, Katsuhiro L.; Nagayama, Takahiro; Ohta, Kouji; Saito, Yoshihiko; Tamura, Yoichi; Tominaga, Nozomu; Uemura, Makoto; Yanagisawa, Kenshi; Yatsu, Yoichi; Yoshida, Michitoshi

    2016-08-01

    We present our optical follow-up observations to search for an electromagnetic counterpart of the first gravitational wave source GW150914 in the framework of the Japanese collaboration for Gravitational wave ElectroMagnetic follow-up (J-GEM), which is an observing group utilizing optical and radio telescopes in Japan, as well as in New Zealand, China, South Africa, Chile, and Hawaii. We carried out a wide-field imaging survey with the Kiso Wide Field Camera (KWFC) on the 1.05 m Kiso Schmidt telescope in Japan and a galaxy-targeted survey with Tripole5 on the B&C 61 cm telescope in New Zealand. Approximately 24 deg2 regions in total were surveyed in i-band with KWFC and 18 nearby galaxies were observed with Tripole5 in g-, r-, and i-bands 4-12 days after the gravitational wave detection. Median 5 σ depths are i ˜ 18.9 mag for the KWFC data and g ˜ 18.9 mag, r ˜ 18.7 mag, and i ˜ 18.3 mag for the Tripole5 data. The probability for a counterpart to be in the observed area is 1.2% in the initial skymap and 0.1% in the final skymap. We do not find any transient source associated to an external galaxy with spatial offset from its center, which is consistent with the local supernova rate.

  20. J-GEM Follow-Up Observations to Search for an Optical Counterpart of The First Gravitational Wave Source GW150914

    CERN Document Server

    Morokuma, Tomoki; Asakura, Yuichiro; Abe, Fumio; Tristram, Paul J; Utsumi, Yousuke; Doi, Mamoru; Fujisawa, Kenta; Itoh, Ryosuke; Itoh, Yoichi; Kawabata, Koji S; Kawai, Nobuyuki; Kuroda, Daisuke; Matsubayashi, Kazuya; Motohara, Kentaro; Murata, Katsuhiro L; Nagayama, Takahiro; Ohta, Kouji; Saito, Yoshihiko; Tamura, Yoichi; Tominaga, Nozomu; Uemura, Makoto; Yanagisawa, Kenshi; Yatsu, Yoichi; Yoshida, Michitoshi

    2016-01-01

    We present our optical follow-up observations to search for an electromagnetic counterpart of the first gravitational wave source GW150914 in the framework of the Japanese collaboration for Gravitational wave ElectroMagnetic follow-up (J-GEM), which is an observing group utilizing optical and radio telescopes in Japan, as well as those in New Zealand, China, South Africa, Chile, and Hawaii. We carried out a wide-field imaging survey with Kiso Wide Field Camera (KWFC) on the 1.05-m Kiso Schmidt telescope in Japan and a galaxy-targeted survey with Tripole5 on the B&C 61-cm telescope in New Zealand. Approximately 24 deg2 regions in total were surveyed in i-band with KWFC and 18 nearby galaxies were observed with Tripole5 in g-, r-, and i-bands 4-12 days after the gravitational wave detection. Median 5-sigma depths are i~18.9 mag for the KWFC data and g~18.9 mag, r~18.7 mag, and i~18.3 mag for the Tripole5 data. Probability for a counterpart to be in the observed area is 1.2% in the initial skymap and 0.1% in...

  1. Search for axions with the CDMS experiment.

    Science.gov (United States)

    Ahmed, Z; Akerib, D S; Arrenberg, S; Bailey, C N; Balakishiyeva, D; Baudis, L; Bauer, D A; Beaty, J; Brink, P L; Bruch, T; Bunker, R; Cabrera, B; Caldwell, D O; Cooley, J; Cushman, P; Dejongh, F; Dragowsky, M R; Duong, L; Figueroa-Feliciano, E; Filippini, J; Fritts, M; Golwala, S R; Grant, D R; Hall, J; Hennings-Yeomans, R; Hertel, S; Holmgren, D; Hsu, L; Huber, M E; Kamaev, O; Kiveni, M; Kos, M; Leman, S W; Mahapatra, R; Mandic, V; Moore, D; McCarthy, K A; Mirabolfathi, N; Nelson, H; Ogburn, R W; Pyle, M; Qiu, X; Ramberg, E; Rau, W; Reisetter, A; Saab, T; Sadoulet, B; Sander, J; Schnee, R W; Seitz, D N; Serfass, B; Sundqvist, K M; Tarka, M; Wang, G; Yellin, S; Yoo, J; Young, B A

    2009-10-02

    We report on the first axion search results from the Cryogenic Dark Matter Search (CDMS) experiment at the Soudan Underground Laboratory. An energy threshold of 2 keV for electron-recoil events allows a search for possible solar axion conversion into photons or local galactic axion conversion into electrons in the germanium crystal detectors. The solar axion search sets an upper limit on the Primakov coupling g(agammagamma) of 2.4x10(-9) GeV-1 at the 95% confidence level for an axion mass less than 0.1 keV/c2. This limit benefits from the first precise measurement of the absolute crystal plane orientations in this type of experiment. The galactic axion search analysis sets a world-leading experimental upper limit on the axioelectric coupling g(aee) of 1.4x10(-12) at the 90% confidence level for an axion mass of 2.5 keV/c2.

  2. Search, Memory, and Choice Error: An Experiment.

    Directory of Open Access Journals (Sweden)

    Adam Sanjurjo

    Full Text Available Multiple attribute search is a central feature of economic life: we consider much more than price when purchasing a home, and more than wage when choosing a job. An experiment is conducted in order to explore the effects of cognitive limitations on choice in these rich settings, in accordance with the predictions of a new model of search memory load. In each task, subjects are made to search the same information in one of two orders, which differ in predicted memory load. Despite standard models of choice treating such variations in order of acquisition as irrelevant, lower predicted memory load search orders are found to lead to substantially fewer choice errors. An implication of the result for search behavior, more generally, is that in order to reduce memory load (thus choice error a limited memory searcher ought to deviate from the search path of an unlimited memory searcher in predictable ways-a mechanism that can explain the systematic deviations from optimal sequential search that have recently been discovered in peoples' behavior. Further, as cognitive load is induced endogenously (within the task, and found to affect choice behavior, this result contributes to the cognitive load literature (in which load is induced exogenously, as well as the cognitive ability literature (in which cognitive ability is measured in a separate task. In addition, while the information overload literature has focused on the detrimental effects of the quantity of information on choice, this result suggests that, holding quantity constant, the order that information is observed in is an essential determinant of choice failure.

  3. A sterile neutrino search at NEOS Experiment

    CERN Document Server

    Ko, Y J; Kim, J Y; Han, B Y; Jang, C H; Jeon, E J; Joo, K K; Kim, H J; Kim, H S; Kim, Y D; Lee, Jaison; Lee, J Y; Lee, M H; Oh, Y M; Park, H K; Park, H S; Park, K S; Seo, K M; Siyeon, Kim; Sun, G M

    2016-01-01

    An experiment to search for light sterile neutrinos was performed at a reactor with a thermal power of 2.8 GW located at the Hanbit nuclear power complex. The search was done with a detector consisting of a ton of Gd-loaded liquid scintillator in a tendon gallery approximately 24 m from the reactor core. The measured antineutrino event rate is 1965 per day with a signal to background ratio of about 23. The shape of the antineutrino energy spectrum obtained from eight-month data-taking period is compared with a hypothesis of oscillations due to active-sterile antineutrino mixing. It is found to be consistent with no oscillation. An excess around 5 MeV prompt energy range is observed as seen in existing longer baseline experiments. Most of the allowed parameter space of $\\Delta m^{2}_{41}\\leq 4$ eV$^{2}$ range for a previously reported reactor antineutrino anomaly, is excluded with a confidence level higher than 95%.

  4. Searching the Gamma-ray Sky for Counterparts to Gravitational Wave Sources: Fermi GBM and LAT Observations of LVT151012 and GW151226

    CERN Document Server

    Racusin, J L; Goldstein, A; Connaughton, V; Wilson-Hodge, C A; Jenke, P; Blackburn, L; Briggs, M S; Broida, J; Camp, J; Christensen, N; Hui, C M; Littenberg, T; Shawhan, P; Singer, L; Veitch, J; Bhat, P N; Cleveland, W; Fitzpatrick, G; Gibby, M H; von Kienlin, A; McBreen, S; Mailyan, B; Meegan, C A; Paciesas, W S; Preece, R D; Roberts, O J; Stanbro, M; Veres, P; Zhang, B -B; Ackermann, M; Albert, A; Atwood, W B; Axelsson, M; Baldini, L; Ballet, J; Barbiellini, G; Baring, M G; Bastieri, D; Bellazzini, R; Bissaldi, E; Blandford, R D; Bloom, E D; Bonino, R; Bregeon, J; Bruel, P; Buson, S; Caliandro, G A; Cameron, R A; Caputo, R; Caragiulo, M; Caraveo, P A; Cavazzuti, E; Charles, E; Chiang, J; Ciprini, S; Costanza, F; Cuoco, A; Cutini, S; D'Ammando, F; de Palma, F; Desiante, R; Digel, S W; Di Lalla, N; Di Mauro, M; Di Venere, L; Drell, P S; Favuzzi, C; Ferrara, E C; Focke, W B; Fukazawa, Y; Funk, S; Fusco, P; Gargano, F; Gasparrini, D; Giglietto, N; Gill, R; Giroletti, M; Glanzman, T; Granot, J; Green, D; Grove, J E; Guillemot, L; Guiriec, S; Harding, A K; Jogler, T; Johannesson, G; Kamae, T; Kensei, S; Kocevski, D; Kuss, M; Larsson, S; Latronico, L; Li, J; Longo, F; Loparco, F; Lubrano, P; Magill, J D; Maldera, S; Malyshev, D; McEnery, J E; Michelson, P F; Mizuno, T; Morselli, A; Moskalenko, I V; Negro, M; Nuss, E; Omodei, N; Orienti, M; Orlando, E; Ormes, J F; Paneque, D; Perkins, J S; Pesce-Rollins, M; Piron, F; Pivato, G; Porter, T A; Principe, G; Raino, S; Rando, R; Razzano, M; Razzaque, S; Reimer, A; Reimer, O; Parkinson, P M Saz; Scargle, J D; Sgro, C; Simone, D; Siskind, E J; Smith, D A; Spada, F; Spinelli, P; Suson, D J; Tajima, H; Thayer, J B; Torres, D F; Troja, E; Uchiyama, Y; Vianello, G; Wood, K S; Wood, M

    2016-01-01

    We present the Fermi Gamma-ray Burst Monitor (GBM) and Large Area Telescope (LAT) observations of the LIGO binary black hole merger event GW151226 and candi- date LVT151012. No candidate electromagnetic counterparts were detected by either the GBM or LAT. We present a detailed analysis of the GBM and LAT data over a range of timescales from seconds to years, using automated pipelines and new techniques for char- acterizing the upper limits across a large area of the sky. Due to the partial GBM and LAT coverage of the large LIGO localization regions at the trigger times for both events, dif- ferences in source distances and masses, as well as the uncertain degree to which emission from these sources could be beamed, these non-detections cannot be used to constrain the variety of theoretical models recently applied to explain the candidate GBM counterpart to GW150914.

  5. Searching for near-infrared counterparts of the faint neutron star X-ray transients XMMU J174716.1-281048 and SAX J1806.5-2215

    CERN Document Server

    Kaur, Ramanpreet; Kamble, Atish; Cackett, Edward M; Kutulla, Ralf; Kaplan, David; Degenaar, Nathalie

    2012-01-01

    We present our near-infrared (NIR) imaging observations of the two neutron star low mass X-ray binaries XMMU J174716.1-281048 and SAX J1806.5-2215 obtained using the PANIC instrument on the 6.5-meter Magellan telescope and the WHIRC instrument on 3.5-meter WIYN telescope. Both sources are members of the group of faint to very-faint X-ray binaries and are undergoing very long X-ray outbursts since 2003 and 2011, respectively- `the quasi-persistent X-ray binaries'. The goal of our observations is to identify the NIR counterpart of both sources. We identified two NIR stars consistent with the Chandra X-ray error circle of XMMU J174716.1-281048 and one for SAX J1806.5-2215. We studied the magnitude variations of the possible counterparts with respect to the UKIRT NIR Galactic plane observations. For XMMU J174716.1-281048, we also investigated the candidate counterparts using the color-color diagram and spectral energy distribution. We observed large variability in one NIR star having position consistent with the ...

  6. BSM Higgs searches with the ATLAS experiment

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00172296; The ATLAS collaboration

    2016-01-01

    The searches for evidence of beyond the Standard Model (BSM) Higgs bosons is a crucial part of the LHC physics program. These searches are mainly driven by two approaches: directly from decays of neutral and charged Higgs bosons, indirectly by interpreting measured mass and cou- plings of light Higgs boson in extensions of the SM. This note reviews the most recent BSM Higgs boson searches performed with ATLAS at LHC using Run I and Run II proton-proton collision data. In particular, limits on new phenomena via coupling measurements, searches for charged and neutral Higgs bosons, double Higgs boson pro- duction and scalar particles decaying to γγ are presented. No significant deviations from the SM background expectations are found in any of the searches and thus the resulting exclusion limits are given.

  7. Searching for high-energy gamma-ray counterparts to Gravitational Wave sources with Fermi-LAT: a needle in a haystack

    CERN Document Server

    Vianello, Giacomo; Chiang, James

    2016-01-01

    At least a fraction of Gravitational Wave (GW) progenitors are expected to emit an electromagnetic (EM) signal in the form of a short gamma-ray burst (sGRB). The discovery of such a transient EM counterpart is challenging because the LIGO/VIRGO localization region is much larger (several hundreds of square degrees) than the field of view of X-ray, optical and radio telescopes. The Fermi Large Area Telescope (LAT) has a wide field of view ($\\sim 2.4$ sr), and detects $\\sim 2-3$ sGRBs per year above 100 MeV. It can detect them not only during the short prompt phase, but also during their long-lasting high-energy afterglow phase. If other wide-field high-energy instruments such as Fermi-GBM, Swift-BAT or INTEGRAL-ISGRI cannot detect or localize with enough precision an EM counterpart during the prompt phase, the LAT can potentially pinpoint it with $\\lesssim 10$ arcmin accuracy during the afterglow phase. This routinely happens with gamma-ray bursts. Moreover, the LAT will cover the entire localization region wi...

  8. SUSY Searches in the ATLAS Experiment

    CERN Document Server

    Lee JR, Lawrence; The ATLAS collaboration

    2014-01-01

    Despite the absence of experimental evidence, weak scale supersymmetry remains one of the best motivated and studied Standard Model extensions. This talk summarises recent ATLAS results for searches for supersymmetric (SUSY) particles. Weak and strong production in both R-Parity conserving and R-Parity violating SUSY scenarios are considered. The searches involved final states including jets, missing transverse momentum, light leptons, taus or photons, as well as long-lived particle signatures.

  9. Searches for Supersymmetry with the ATLAS Experiment

    CERN Document Server

    Lee, Lawrence; The ATLAS collaboration

    2017-01-01

    Despite the absence of experimental evidence, weak scale supersymmetry remains one of the best motivated and studied Standard Model extensions. This talk summarises recent ATLAS results for searches for supersymmetric (SUSY) particles. Weak and strong production in both R-Parity conserving and R-Parity violating SUSY scenarios are considered. The searches used proton-proton collisions at sqrt{s} = 13 TeV, and involved final states including jets, missing transverse momentum, light leptons as well as long-lived particle signatures.

  10. X(3872) and its bottomonium counterpart at ATLAS

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00218332; The ATLAS collaboration

    2016-01-01

    We present the measurement of the differential cross-section of the X(3872) state through its decays to $J/\\psi \\pi^+ \\pi^-$ final state . The cross-section was extracted for both prompt and non-prompt production. The existence of the X(3872) suggests the presence of its bottomonium counterpart $X_b$. Search for $X_b$ with the ATLAS experiment in several final states, including $\\Upsilon \\pi^+ \\pi^-$, is presented.

  11. Higgs Boson search at the CMS experiment

    Directory of Open Access Journals (Sweden)

    Choudhury Somnath

    2014-04-01

    Full Text Available The results of the search for the Standard Model (SM Higgs Boson with the CMS detector in proton-proton collisions at the LHC at 7 TeV center-of-mass energy are reported. A large number of the Higgs Boson decay channels in the mass range from 110 GeV to 600 GeV are considered, and combined upper limits on the production cross section as a function of the Higgs Boson mass are derived. The SM Higgs is excluded at 95% confidence level in the mass range between 127.5 GeV and 600 GeV. In addition, searches for Higgs Bosons in scenarios Beyond the Standard Model (BSM lead to improved constraints on the Higgs sector of BSM theories such as supersymmetry.

  12. Automated Search for new Quantum Experiments

    Science.gov (United States)

    Krenn, Mario; Malik, Mehul; Fickler, Robert; Lapkiewicz, Radek; Zeilinger, Anton

    2016-03-01

    Quantum mechanics predicts a number of, at first sight, counterintuitive phenomena. It therefore remains a question whether our intuition is the best way to find new experiments. Here, we report the development of the computer algorithm Melvin which is able to find new experimental implementations for the creation and manipulation of complex quantum states. Indeed, the discovered experiments extensively use unfamiliar and asymmetric techniques which are challenging to understand intuitively. The results range from the first implementation of a high-dimensional Greenberger-Horne-Zeilinger state, to a vast variety of experiments for asymmetrically entangled quantum states—a feature that can only exist when both the number of involved parties and dimensions is larger than 2. Additionally, new types of high-dimensional transformations are found that perform cyclic operations. Melvin autonomously learns from solutions for simpler systems, which significantly speeds up the discovery rate of more complex experiments. The ability to automate the design of a quantum experiment can be applied to many quantum systems and allows the physical realization of quantum states previously thought of only on paper.

  13. Automated Search for new Quantum Experiments.

    Science.gov (United States)

    Krenn, Mario; Malik, Mehul; Fickler, Robert; Lapkiewicz, Radek; Zeilinger, Anton

    2016-03-04

    Quantum mechanics predicts a number of, at first sight, counterintuitive phenomena. It therefore remains a question whether our intuition is the best way to find new experiments. Here, we report the development of the computer algorithm Melvin which is able to find new experimental implementations for the creation and manipulation of complex quantum states. Indeed, the discovered experiments extensively use unfamiliar and asymmetric techniques which are challenging to understand intuitively. The results range from the first implementation of a high-dimensional Greenberger-Horne-Zeilinger state, to a vast variety of experiments for asymmetrically entangled quantum states-a feature that can only exist when both the number of involved parties and dimensions is larger than 2. Additionally, new types of high-dimensional transformations are found that perform cyclic operations. Melvin autonomously learns from solutions for simpler systems, which significantly speeds up the discovery rate of more complex experiments. The ability to automate the design of a quantum experiment can be applied to many quantum systems and allows the physical realization of quantum states previously thought of only on paper.

  14. Automated Search for new Quantum Experiments

    CERN Document Server

    Krenn, Mario; Fickler, Robert; Lapkiewicz, Radek; Zeilinger, Anton

    2015-01-01

    Quantum mechanics predicts a number of at first sight counterintuitive phenomena. It is therefore a question whether our intuition is the best way to find new experiments. Here we report the development of the computer algorithm Melvin which is able to find new experimental implementations for the creation and manipulation of complex quantum states. And indeed, the discovered experiments extensively use unfamiliar and asymmetric techniques which are challenging to understand intuitively. The results range from the first implementation of a high-dimensional Greenberger-Horne-Zeilinger (GHZ) state, to a vast variety of experiments for asymmetrically entangled quantum states - a feature that can only exist when both the number of involved parties and dimensions is larger than 2. Additionally, new types of high-dimensional transformations are found that perform cyclic operations. Melvin autonomously learns from solutions for simpler systems, which significantly speeds up the discovery rate of more complex experim...

  15. Precision experiments to search for the fifth force

    Energy Technology Data Exchange (ETDEWEB)

    Faller, J.E.; Speake, C.C. (Joint Institute for Lab. Astrophysics, National Bureau of Standards, Boulder, CO (US)); Fischbach, E. (Purdue Univ., Lafayette, IN (USA). Dept. of Physics); Fujii, Y. (Institute of Physics, Univ. of Tokyo-Komaba, Meguro-Ku, Tokyo 153 (JP)); Kuroda, K. (National Research Lab. of Metrology, 1-1-4, Umezono, Tsukuba-shi, Ibaraki 305 (JP)); Paik, H.J. (Maryland Univ., College Park, MD (USA). Dept. of Physics and Astronomy)

    1989-04-01

    The suggestion of a possible new fifth force of nature, has prompted a large number of high precision experiments to search for its presence. After reviewing the motivation for this suggestion, the authors describe some of the experiments that are presently underway, and the results that have been obtained to date.

  16. Magnetic Monopole Search with the SLIM Experiment

    CERN Document Server

    Medinaceli, E

    2008-01-01

    The SLIM experiment was an array of 427 m^2 of nuclear track detectors, exposed at a high altitude laboratory (Chacaltaya, Bolivia, 5230 m a.s.l.), for ~4.22 years. SLIM was sensitive to downgoing intermediate mass magnetic monopoles with masses in the range 10^5 to 10^12 GeV. The analysis of the full detector gives a flux upper limit of 1.3x10^{-15} 1/(cm^2*s*sr) (90% C.L.) for downgoing fast intermediate magnetic monopoles.

  17. Axion Search with Q & A Experiment

    CERN Document Server

    Mei, Hsien-Hao; Chen, Sheng-Jui; Pan, Sheau-Shi

    2010-01-01

    Dark matter is a focused issue in galactic evolution and cosmology. Axion is a viable particle candidate for dark matter. Its interaction with photon is an effective way to detect it, e.g., pseudoscalar-photon interaction will generate vacuum dichroism in a magnetic field. Motivated to measure the QED vacuum birefringence and to detect pseudoscalar-photon interaction, we started to build up the Q & A experiment (QED [Quantum Electrodynamics] and Axion experiment) in 1994. In this talk, we first give a brief historical account of planet hunting and dark matter evidence. We then review our 3.5 m Fabry-Perot interferometer together with our results of measuring vacuum dichroism and gaseous Cotton-Mouton effects. Our first results give (-0.2 $\\pm$ 2.8) $\\times$ 10$^{-13}$ rad/pass, at 2.3 T with 18,700 passes through a 0.6 m long magnet, for vacuum dichroism measurement. We are upgrading our interferometer to 7 m arm-length with a new 1.8 m 2.3 T permanent magnet capable of rotation up to 13 cycles per second...

  18. Sterile neutrino search in the STEREO experiment

    Energy Technology Data Exchange (ETDEWEB)

    Buck, Christian; Lindner, Manfred; Roca, Christian [MPIK (Germany)

    2016-07-01

    In neutrino oscillations, a canonical understanding has been established during the last decades after the measurement of the mixing angles θ{sub 12}, θ{sub 23}, θ{sub 13} via solar, atmospheric and, most recently, reactor neutrinos. However, the re-evaluation of the reactor neutrino theoretical flux has forced a re-analysis of most reactor neutrino measurements at short distances. This has led to an unexpected experimental deficit of neutrinos with respect to the theory that needs to be accommodated, commonly known as the ''reactor neutrino anomaly''. This deficit can be interpreted as the existence of a light sterile neutrino state into which reactor neutrinos oscillate at very short distances. The STEREO experiment aims to find an evidence of such oscillations. The ILL research reactor in Grenoble (France) operates at a power of 58MW and provides a large flux of electron antineutrinos with an energy range of a few MeV. These neutrinos will be detected in a 2000 liter organic liquid scintillator detector doped with Gadolinium and consisting of 6 cells stacked along the direction of the core. Given the proximity of the detector, neutrinos will only travel a few meters until they interact with the scintillator. The detector will be placed about 10 m from the reactor core, allowing STEREO to be sensitive to oscillations into the above mentioned neutrino sterile state. The project presents a high potential for a discovery that would impact deeply the paradigms of neutrino oscillations and in consequence the current understanding of particle physics and cosmology.

  19. The Heavy Photon Search experiment at Jefferson Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Celentano, Andrea [INFN-GENOVA

    2014-11-01

    The Heavy Photon Search experiment (HPS) at Jefferson Laboratory will search for a new U(1) massive gauge boson, or "heavy-photon", mediator of a new fundamental interaction, called "dark-force", that couples to ordinary photons through kinetic mixing. HPS has sensitivity in the mass range 20 MeV – 1 GeV and coupling epsilon2 between 10-5 and 10-10. The HPS experiment will look for the e+e- decay of the heavy photon, by resonance search and detached vertexing, in an electron beam fixed target experiment. HPS will use a compact forward spectrometer, which employs silicon microstrip detectors for vertexing and tracking, and a PbWO4 electromagnetic calorimeter for energy measurement and fast triggering.

  20. The Heavy Photon Search experiment at Jefferson Laboratory

    Directory of Open Access Journals (Sweden)

    De Napoli Marzio

    2015-01-01

    Full Text Available Many beyond Standard Model theories predict a new massive gauge boson, aka “dark” or “heavy photon”, directly coupling to hidden sector particles with dark charge. The heavy photon is expected to mix with the Standard Model photon through kinetic mixing and therefore couple weakly to normal charge. The Heavy Photon Search (HPS experiment will search for the heavy photon at the Thomas Jefferson National Accelerator Facility (JLab, in the mass range 20-1000 MeV/c2 and coupling to electric charge ϵ2 = α′/α in the range 10−5 to 10−10. HPS will look for the e+e− decay channel of heavy photons radiated by electron Bremsstrahlung, employing both invariant mass search and detached vertexing techniques. The experiment employs a compact forward spectrometer comprising silicon microstrip detectors for vertexing and tracking and an electromagnetic calorimeter for particle identification and triggering.

  1. Experiments searching for new interactions in nuclear beta-decay

    NARCIS (Netherlands)

    Jungmann, Klaus P.; Brown, BA; Engel, J; Haxton, W; RamseyMusolf, M; Romalis, M; Savard, G

    2009-01-01

    Precision measurements of beta-decays in nuclei, muons and neutrons allow to search for non V-A contributions in, weak interactions and to set; limits on parameters relevant to theoretical models beyond standard theory. Novel experiments are possible in particular at, presently operating stable beam

  2. The GERDA experiment for the search of 0\

    CERN Document Server

    Ackermann, K -H; Allardt, M; Altmann, M; Andreotti, E; Bakalyarov, A M; Balata, M; Barabanov, I; Heider, M Barnabe; Barros, N; Baudis, L; Bauer, C; Becerici-Schmidt, N; Bellotti, E; Belogurov, S; Belyaev, S T; Benato, G; Bettini, A; Bezrukov, L; Bode, T; Brudanin, V; Brugnera, R; Budjas, D; Caldwell, A; Cattadori, C; Chernogorov, A; Chkvorets, O; Cossavella, F; D`Andragora, A; Demidova, E V; Denisov, A; di Vacri, A; Domula, A; Egorov, V; Falkenstein, R; Ferella, A; Freund, K; Froborg, F; Frodyma, N; Gangapshev, A; Garfagnini, A; Gasparro, J; Gazzana, S; de Orduna, R Gonzalez; Grabmayr, P; Gurentsov, V; Gusev, K; Guthikonda, K K; Hampel, W; Hegai, A; Heisel, M; Hemmer, S; Heusser, G; Hofmann, W; Hult, M; Inzhechik, L V; Ioannucci, L; Csalty, J Janicsko; Jochum, J; Junker, M; Kankanyan, R; Kianovsky, S; Kihm, T; Kiko, J; Kirpichnikov, I V; Kirsch, A; Klimenko, A; Knapp, M; Knöpfle, K T; Kochetov, O; Kornoukhov, V N; Kröninger, K; Kusminov, V; Laubenstein, M; Lazzaro, A; Lebedev, V I; Lehnert, B; Lenz, D; Liao, H; Lindner, M; Lippi, I; Liu, J; Liu, X; Lubashevskiy, A; Lubsandorzhiev, B; Machado, A A; Majorovits, B; Maneschg, W; Marissens, G; Mayer, S; Meierhofer, G; Nemchenok, I; Niedermeier, L; Nisi, S; Oehm, J; O'Shaughnessy, C; Pandola, L; Peiffer, P; Pelczar, K; Pullia, A; Riboldi, S; Ritter, F; Alvarez, C Rossi; Sada, C; Salathe, M; Schmitt, C; Schönert, S; Schreiner, J; Schubert, J; Schulz, O; Schwan, U; Schwingenheuer, B; Seitz, H; Shevchik, E; Shirchenko, M; Simgen, H; Smolnikov, A; Stanco, L; Stelzer, F; Strecker, H; Tarka, M; Trunk, U; Ur, C A; Vasenko, A A; Vogt, S; Volynets, O; von Sturm, K; Wagner, V; Walter, M; Wegmann, A; Wojcik, M; Yanovich, E; Zavarise, P; Zhitnikov, I; Zhukov, S V; Zinatulina, D; Zuber, K; Zuzel, G

    2012-01-01

    The GERDA collaboration is performing a search for neutrinoless double beta decay of ^{76}Ge with the eponymous detector. The experiment has been installed and commissioned at the Laboratori Nazionali del Gran Sasso and has started operation in November 2011. The design, construction and first operational results are described, along with detailed information from the R&D phase.

  3. Prospects for future experiments to search for nucleon decay

    Energy Technology Data Exchange (ETDEWEB)

    Ayres, D.S.; Heller, K.; LoSecco, J.; Mann, A.K.; Marciano, W.; Shrock, R.E.; Thornton, R.K.

    1982-01-01

    We review the status of theoretical expectations and experimental searches for nucleon decay, and predict the sensitivities which could be reached by future experiments. For the immediate future, we concur with the conclusions of the 1982 Summer Workshop on Proton Decay Experiments: all detectors now in operation or construction will be relatively insensitive to some potentially important decay modes. Next-generation experiments must therefore be designed to search for these modes, and should be undertaken whether or not present experiments detect nucleon decay in other modes. These future experiments should be designed to push the lifetime limits on all decay modes to the levels at which irreducible cosmic-ray neutrino-induced backgrounds become important. Since the technology for these next-generation experiments is available now, the timetable for starting work on them will be determined by funding constraints and not by the need for extensive development of detectors. Efforts to develop advanced detector techniques should also be pursued, in order to mount more sensitive searches than can be envisioned using current technology, or to provide the most precise measurements possible of the properties of the nucleon decay interaction if it should occur at a detectable rate.

  4. Searching for light dark matter with the SLAC millicharge experiment.

    Science.gov (United States)

    Diamond, M; Schuster, P

    2013-11-27

    New sub-GeV gauge forces ("dark photons") that kinetically mix with the photon provide a promising scenario for MeV-GeV dark matter and are the subject of a program of searches at fixed-target and collider facilities around the world. In such models, dark photons produced in collisions may decay invisibly into dark-matter states, thereby evading current searches. We reexamine results of the SLAC mQ electron beam dump experiment designed to search for millicharged particles and find that it was strongly sensitive to any secondary beam of dark matter produced by electron-nucleus collisions in the target. The constraints are competitive for dark photon masses in the ~1-30 MeV range, covering part of the parameter space that can reconcile the apparent (g-2)(μ) anomaly. Simple adjustments to the original SLAC search for millicharges may extend sensitivity to cover a sizable portion of the remaining (g-2)(μ) anomaly-motivated region. The mQ sensitivity is therefore complementary to ongoing searches for visible decays of dark photons. Compared to existing direct-detection searches, mQ sensitivity to electron-dark-matter scattering cross sections is more than an order of magnitude better for a significant range of masses and couplings in simple models.

  5. Dark Matter Searches and Prospects at the ATLAS Experiment

    CERN Document Server

    Taylor, Wendy; The ATLAS collaboration

    2017-01-01

    Despite the recent discovery of the Higgs boson contributing to the success of the Standard Model, the large excess of dark matter in the Universe remains one of the outstanding questions in science. This excess cannot be explained by Standard Model particles. A compelling hypothesis is that dark matter comprises particles that can be produced at the LHC, called Weakly Interacting Massive Particles (WIMPs). This talk presents a number of ATLAS searches for WIMP dark matter, outlining the main theoretical benchmarks and issues in terms of complementarity with direct and indirect detection experiments, and presents the prospects for dark matter searches at future LHC runs.

  6. A Dynamic Methodology for Improving the Search Experience

    OpenAIRE

    2006-01-01

    In the early years of modern information retrieval, the fundamental way in which we understood and evaluated search performance was by measuring precision and recall. In recent decades, however, models of evaluation have expanded to incorporate the information-seeking task and the quality of its outcome, as well as the value of the information to the user. We have developed a systems engineering-based methodology for improving the whole search experience. The approach focuses on understanding...

  7. Final results of magnetic monopole searches with the MACRO experiment

    CERN Document Server

    Ambrosio, M; Auriemma, G; Bakari, D; Baldini, A; Barbarino, G C; Barish, B C; Battistoni, G; Becherini, Y; Bellotti, R; Bemporad, C; Bernardini, P; Bilokon, H; Bloise, C; Bower, C; Brigida, M; Bussino, S; Cafagna, F; Calicchio, M; Campana, D; Carboni, M; Caruso, R; Cecchini, S; Cei, F; Chiarella, V; Chiarusi, T; Choudhary, B C; Coutu, S; Cozzi, M; De Cataldo, G; Dekhissi, H; De Marzo, C; De Mitri, I; Derkaoui, J E; De Vincenzi, M; Di Credico, A; Erriquez, O; Favuzzi, C; Forti, C; Fusco, P; Giacomelli, G; Giannini, G; Giglietto, N; Giorgini, M; Grassi, M; Grillo, A; Guarino, F; Gustavino, C; Habig, A; Hanson, K; Heinz, R; Iarocci, E; Katsavounidis, E; Katsavounidis, I; Kearns, E; Kim, H; Kyriazopoulou, S; Kumar, A; Lamanna, E; Lane, C; Levin, D S; Lipari, P; Longley, N P; Longo, M J; Loparco, F; Maaroufi, F; Mancarella, G; Mandrioli, G; Manzoor, S; Margiotta, A; Marini, A; Martello, D; Marzari-Chiesa, A; Matteuzzi, D; Mazziotta, M N; Michael, D G; Monacelli, P; Montaruli, T; Monteno, M; Mufson, S L; Musser, J; Nicolò, D; Nolty, R; Orth, C; Osteria, G; Palamara, O; Patera, V; Patrizii, L; Pazzi, R; Peck, C W; Perrone, L; Petrera, S; Pistilli, P; Popa, V; Rainó, A; Reynoldson, J; Ronga, F; Rrhioua, A; Satriano, C; Scapparone, E; Scholberg, K; Sciubba, A; Serra, P; Sioli, M; Sirri, G; Sitta, M; Spinelli, P; Spinetti, M; Spurio, M; Steinberg, R; Stone, J L; Sulak, L R; Surdo, A; Tarle, G; Togo, V; Vakili, M; Walter, C W; Webb, R

    2002-01-01

    We present the final results obtained by the MACRO experiment in the search for GUT magnetic monopoles in the penetrating cosmic radiation, for the range 4*10/sup -5/< beta <1. Several searches with all the MACRO sub-detectors (i.e. scintillation counters, limited streamer tubes and nuclear track detectors) were performed, both in stand alone and combined ways. No candidates were detected and a 90% Confidence Level (C.L.) upper limit to the local magnetic monopole flux was set at the level of 1.4*10/sup -16/ cm/sup -2/ s/sup -1/ sr /sup -1/. This result is the first experimental limit obtained in direct searches which is well below the Parker bound in the whole beta range in which GUT magnetic monopoles are expected. (37 refs).

  8. Photon regeneration experiment for axion search using x-rays.

    Science.gov (United States)

    Battesti, R; Fouché, M; Detlefs, C; Roth, T; Berceau, P; Duc, F; Frings, P; Rikken, G L J A; Rizzo, C

    2010-12-17

    In this Letter we describe our novel photon regeneration experiment for the axionlike particle search using an x-ray beam with a photon energy of 50.2 and 90.7 keV, two superconducting magnets of 3 T, and a Ge detector with a high quantum efficiency. A counting rate of regenerated photons compatible with zero has been measured. The corresponding limits on the pseudoscalar axionlike particle-two-photon coupling constant is obtained as a function of the particle mass. Our setup widens the energy window of purely terrestrial experiments devoted to the axionlike particle search by coupling to two photons. It also opens a new domain of experimental investigation of photon propagation in magnetic fields.

  9. The search for exotic baryons at the HERMES experiment

    Energy Technology Data Exchange (ETDEWEB)

    Deconinck, Wouter

    2008-07-15

    One of the interesting questions of Quantum Chromodynamics, the theory that governs the interactions between quarks and gluons, has been whether it is possible to observe hadrons which can not be explained as a combination of only two or three valence quarks. In numerous searches the existence of these exotic hadrons could not be confirmed. Recently, calculations based on the quark soliton model predicted the narrow exotic baryons {theta}{sup +} and {xi}{sup --}. A narrow resonance identified as the {theta}{sup +} was observed by several experiments at the predicted mass of 1540 MeV, but later followed by several dedicated experiments that could not confirm these positive results. At the HERMES experiment a search for the quasi-real photoproduction of the exotic baryon {theta}{sup +} on a deuterium target and the subsequent decay through pK{sup 0}{sub S} {yields} p{pi}{sup +}{pi}{sup -} revealed a narrow resonance in the pK{sup 0}{sub S} invariant mass distribution at 1528 MeV. In the search for the corresponding antiparticle {xi}{sup --} the result is consistent with zero events. In this thesis we present the search for the exotic baryon {xi}{sup --} on a deuterium target in the data sample used for the observation of the {theta}{sup +}. An upper limit on the cross section of the exotic baryon {xi}{sup --} is determined. The search for the exotic baryon {theta}{sup +} on hydrogen and deuterium targets at the HERMES experiment is extensively discussed. The event mixing method can be used to estimate the distribution of background events. Several difficulties with this method were addressed, but the background description in the case of the exotic baryon {theta}{sup +} remains unconvincing. Between the years 2002 and 2005 the HERMES experiment operated with a magnetic holding field around the hydrogen target. A method for the reconstruction of displaced vertices in this field was developed. The data collected during the years 2006 and 2007 offer an integrated

  10. Axion Search by Laser-based Experiment OSQAR

    OpenAIRE

    Sulc, Miroslav; Pugnat, Pierre; Ballou, Rafik; Deferne, Guy; Duvillaret, Lionel; Flekova, Lucie; Finger, Michael; Finger Jr, Michael; Hošek, Jan; Husek, Thomas; Jost, Rémy; Kral, Miroslav; Kunc, Štěpán; Macuchova, Karolina; Meissner, Krzysztof,

    2012-01-01

    International audience; Laser-based experimentOSQAR in CERN is aimed to the search of the axions by twomethods. The photon regeneration experiment is using two LHC dipole magnets of the length 14.3 m and magnetic field 9.5 T equipped with an optical barrier at the end of the first magnet. It looks as light shining through the wall. No excess of events above the background was detected at this arrangement. Nevertheless, this result extends the exclusion region for the axion mass. The second me...

  11. The Heavy Photon Search experiment at Jefferson Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    De Napoli, Marzio [Istituto Nazionale di Fisica Nucleare (INFN), Catania (Italy). Lab. et al.

    2015-06-01

    Many beyond Standard Model theories predict a new massive gauge boson, a.k.a. 'dark' or 'heavy photon', directly coupling to hidden sector particles with dark charge. The heavy photon is expected to mix with the Standard Model photon through kinetic mixing and therefore couple weakly to normal charge. The Heavy Photon Search (HPS) experiment will search for the heavy photon at the Thomas Jefferson National Accelerator Facility (JLab), in the mass range 20-1000 MeV/c2 and coupling to electric charge ϵ2 = α'/α in the range 10-5 to 10-10. HPS will look for the e+e- decay channel of heavy photons radiated by electron Bremsstrahlung, employing both invariant mass search and detached vertexing techniques. The experiment employs a compact forward spectrometer comprising silicon microstrip detectors for vertexing and tracking and an electromagnetic calorimeter for particle identification and triggering.

  12. Sterile Neutrino Searches in MINOS and MINOS+ Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Junting [Univ. of Texas, Austin, TX (United States)

    2015-05-01

    This dissertation presents the searches on sterile neutrinos using the data collected in MINOS+ Experiment from September 2013 to September 2014, and the full data set of MINOS Experiment collected from 2005 to 2012. Anomalies in short baseline experiments, such as LSND and MiniBooNE, showed hints of sterile neutrinos, a type of neutrino that does not interact with the Standard Model particles. In this work, two models are considered: 3+1 and large extra dimension (LED). In the 3+1 model, one sterile neutrino state is added into the standard oscillation scheme consisting of three known active neutrino states ve, vμ and vτ. In the LED model, sterile neutrinos arise as Kaluza-Klein (KK) states due to assumed large extra dimensions. Mixing between sterile and active neutrino states may modify the oscillation patterns observed in the MINOS detectors. Both searches yield null results. For 3+1, a combined fit of MINOS and MINOS+ data gives a stronger limit on θ24 in the range of 10-2 eV2 < Δm412 < 1 eV2 than previous experiments. For LED, with the complete MINOS data set, the size of extra dimensions is constrained to be smaller than ~ 0.35 μm at 90% C.L. in the limit of a vanishing lightest neutrino mass.

  13. A Dynamic Methodology for Improving the Search Experience

    Directory of Open Access Journals (Sweden)

    Marcia D. Kerchner

    2006-06-01

    Full Text Available In the early years of modern information retrieval, the fundamental way in which we understood and evaluated search performance was by measuring precision and recall. In recent decades, however, models of evaluation have expanded to incorporate the information-seeking task and the quality of its outcome, as well as the value of the information to the user. We have developed a systems engineering-based methodology for improving the whole search experience. The approach focuses on understanding users’ information-seeking problems, understanding who has the problems, and applying solutions that address these problems. This information is gathered through ongoing analysis of site-usage reports, satisfaction surveys, Help Desk reports, and a working relationship with the business owners.

  14. Search for Rare B Meson Decays at the BABAR Experiment

    Science.gov (United States)

    Cheaib, R.; BABAR Collaboration

    2016-11-01

    b → s transitions are flavour-changing neutral current (FCNC) processes that play an important role in the search for physics beyond the Standard Model (SM). Contributions from virtual particles in the loop are predicted to deviate observables, such as the branching fraction, from their SM expectations. Using data from the BaBar experiment, we present the first search for the rare decay B + → K+ τ+τ-. The BABAR results on the measurement of the angular asymmetries of B → K* l + l -, where l = e or μ, are also reported. In addition, using a time-dependent analysis of B → K s 0π+π-γ, the mixing induced CP-asymmetry for the radiative FCNC decay, B → K s 0ργ, is measured, along with an amplitude analysis of the mKπ and mKππ spectrum.

  15. Axion search by laser-based experiment OSQAR

    Science.gov (United States)

    Sulc, M.; Pugnat, P.; Ballou, R.; Deferne, G.; Duvillaret, L.; Flekova, L.; Finger, M.; Finger, M.; Hosek, J.; Husek, T.; Jost, R.; Kral, M.; Kunc, S.; Macuchova, K.; Meissner, K. A.; Morville, J.; Romanini, D.; Schott, M.; Siemko, A.; Slunecka, M.; Vitrant, G.; Zicha, J.

    2013-08-01

    Laser-based experiment OSQAR in CERN is aimed to the search of the axions by two methods. The photon regeneration experiment is using two LHC dipole magnets of the length 14.3 m and magnetic field 9.5 T equipped with an optical barrier at the end of the first magnet. It looks as light shining through the wall. No excess of events above the background was detected at this arrangement. Nevertheless, this result extends the exclusion region for the axion mass. The second method wants to measure the ultra-fine vacuum magnetic birefringence for the first time. An optical scheme with electro-optical modulator has been proposed, validated and subsequently improved. Cotton-Mouton constant for air was determined in this experiment setup.

  16. Axion search by laser-based experiment OSQAR

    Energy Technology Data Exchange (ETDEWEB)

    Sulc, M., E-mail: miroslav.sulc@tul.cz [Technical University of Liberec (Czech Republic); Pugnat, P. [LNCMI-G, CNRS-UJF-UPS-INSA, BP 166, 38042 Grenoble Cedex-9 (France); Ballou, R. [Institut Néel, CNRS and Université Joseph Fourier, BP 166, 38042 Grenoble Cedex-9 (France); Deferne, G. [CERN, CH-1211 Geneva-23 (Switzerland); Duvillaret, L. [IMEP-LAHC, UMR CNRS 5130, Minatec-INPG, 3 parvis Louis Néel, BP 257, 38016 Grenoble Cedex-1 (France); Flekova, L. [Czech Technical University, Faculty of Mechanical Engineering, Prague (Czech Republic); Finger, M.; Finger, M. [Charles University, Faculty of Mathematics and Physics, Prague (Czech Republic); Hosek, J. [Czech Technical University, Faculty of Mechanical Engineering, Prague (Czech Republic); Husek, T. [Charles University, Faculty of Mathematics and Physics, Prague (Czech Republic); Jost, R. [LSP, UMR CNRS 5588, Université Joseph Fourier, BP 87, 38402 Saint-Martin d' Hères (France); Kral, M. [Czech Technical University, Faculty of Mechanical Engineering, Prague (Czech Republic); Kunc, S. [Technical University of Liberec (Czech Republic); Macuchova, K. [Czech Technical University, Faculty of Mechanical Engineering, Prague (Czech Republic); Meissner, K.A. [Institute of Theoretical Physics, University of Warsaw (Poland); Morville, J. [LASIM, UMR CNRS 5579, Université Claude Bernard Lyon-1, 69622 Villeurbanne (France); Romanini, D. [LSP, UMR CNRS 5588, Université Joseph Fourier, BP 87, 38402 Saint-Martin d' Hères (France); Schott, M.; Siemko, A. [CERN, CH-1211 Geneva-23 (Switzerland); Slunecka, M. [Charles University, Faculty of Mathematics and Physics, Prague (Czech Republic); and others

    2013-08-01

    Laser-based experiment OSQAR in CERN is aimed to the search of the axions by two methods. The photon regeneration experiment is using two LHC dipole magnets of the length 14.3 m and magnetic field 9.5 T equipped with an optical barrier at the end of the first magnet. It looks as light shining through the wall. No excess of events above the background was detected at this arrangement. Nevertheless, this result extends the exclusion region for the axion mass. The second method wants to measure the ultra-fine vacuum magnetic birefringence for the first time. An optical scheme with electro-optical modulator has been proposed, validated and subsequently improved. Cotton–Mouton constant for air was determined in this experiment setup.

  17. Status of the DAMIC direct dark matter search experiment

    CERN Document Server

    Aguilar-Arevalo, A; Bertou, X; Boule, D; Butner, M; Cancelo, G; Vázquez, A Castañeda; Chavarría, A E; Neto, J R T de Melo; Dixon, S; D'Olivo, J C; Estrada, J; Moroni, G Fernandez; Torres, K P Hernández; Izraelevitch, F; Kavner, A; Kilminster, B; Lawson, I; Liao, J; López, M; Molina, J; Moreno-Granados, G; Pena, J; Privitera, P; Sarkis, Y; Scarpine, V; Schwartz, T; Haro, M Sofo; Tiffenberg, J; Machado, D Torres; Trillaud, F; You, X; Zhou, J

    2015-01-01

    The DAMIC experiment uses fully depleted, high resistivity CCDs to search for dark matter particles. With an energy threshold $\\sim$50 eV$_{ee}$, and excellent energy and spatial resolutions, the DAMIC CCDs are well-suited to identify and suppress radioactive backgrounds, having an unrivaled sensitivity to WIMPs with masses $<$6 GeV/$c^2$. Early results motivated the construction of a 100 g detector, DAMIC100, currently being installed at SNOLAB. This contribution discusses the installation progress, new calibration efforts near the threshold, a preliminary result with 2014 data, and the prospects for physics results after one year of data taking.

  18. Status of the DAMIC Direct Dark Matter Search Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar-Arevalo, A.; et al.

    2015-09-30

    The DAMIC experiment uses fully depleted, high resistivity CCDs to search for dark matter particles. With an energy threshold $\\sim$50 eV$_{ee}$, and excellent energy and spatial resolutions, the DAMIC CCDs are well-suited to identify and suppress radioactive backgrounds, having an unrivaled sensitivity to WIMPs with masses $<$6 GeV/$c^2$. Early results motivated the construction of a 100 g detector, DAMIC100, currently being installed at SNOLAB. This contribution discusses the installation progress, new calibration efforts near the threshold, a preliminary result with 2014 data, and the prospects for physics results after one year of data taking.

  19. New Results from the Cryogenic Dark Matter Search Experiment

    CERN Document Server

    Armel, M S; Baudis, L; Bauer, D A; Bolozdynya, A I; Brink, P L; Bunker, R; Cabrera, B; Caldwell, D O; Castle, J P; Chang, C L; Clarke, R M; Crisler, M B; Cushman, P B; Davies, A K; Dixon, R; Driscoll, D D; Duong, L; Emes, J; Ferril, R; Gaitskell, R J; Golwala, S R; Haldeman, M; Hellmig, J; Hennessey, M; Holmgren, D; Huber, M E; Kamat, S; Kurylowicz, M; Lu, A; Mahapatra, R; Mandic, V; Martinis, J M; Meunier, P; Mirabolfathi, N; Nam, S W; Nelson, H; Nelson, R; Ogburn, R W; Perales, J; Perera, T A; Perillo-Isaac, M C; Rau, W; Reisetter, A; Ross, R R; Saab, T; Sadoulet, B; Sander, J; Savage, C; Schnee, R W; Seitz, D N; Shutt, T A; Smith, G; Spadafora, A L; Thompson, J P F; Tomada, A; Wang, G; Yellin, S; Young, B A

    2003-01-01

    Using improved Ge and Si detectors, better neutron shielding, and increased counting time, the Cryogenic Dark Matter Search (CDMS) experiment has obtained stricter limits on the cross section of weakly interacting massive particles (WIMPs) elastically scattering from nuclei. Increased discrimination against electromagnetic backgrounds and reduction of neutron flux confirm WIMP-candidate events previously detected by CDMS were consistent with neutrons and give limits on spin-independent WIMP interactions which are >2X lower than previous CDMS results for high WIMP mass, and which exclude new parameter space for WIMPs with mass between 8-20 GeV/c^2.

  20. Searches for exotic stable massive particles with the ATLAS experiment

    CERN Document Server

    Ohm, Christian; Moa, Torbjörn

    2011-01-01

    This thesis presents two signature-based searches for exotic long-lived particles using experimental data collected by the ATLAS experiment at the Large Hadron Collider (LHC) at CERN. At the LHC, proton-proton collisions take place at the world-record center-of-mass energy of 7 TeV and luminosities of up to $3\\times 10^{33}cm^{-2}s^{-1}$. New physics has long been anticipated at the LHC and in this thesis two searches for hitherto unobserved particles are presented. Long-lived heavy hadrons have been predicted by models of supersymmetry, and these were the target of the first physics analysis. Using measurements of timing and energy loss, a search for so-called $R$-hadrons was performed. No excess was observed in the data, and new lower limits were established on the masses of meta-stable supersymmetric particles with color charge: $m_{\\tilde{g}} > 562-586$ GeV (depending on choice of scattering model), $m_{\\tilde{t}} > 309$ GeV and $m_{\\tilde{b}} > 294$ GeV. These constraints are the most stringent limits pu...

  1. Supersymmetry Searches in Dilepton Final States with the ATLAS Experiment

    CERN Document Server

    Lungwitz, Matthias

    One of the main goals of the ATLAS experiment at the Large Hadr on Collider (LHC) at CERN in Geneva is the search for new physics beyond the Standa rd Model. In 2011, proton- proton collisions were performed at the LHC at a center of mas s energy of 7 TeV and an in- tegrated luminosity of 4 . 7 fb − 1 was recorded. This dataset can be tested for one of the most promising theories beyond limits achieved thus far: supers ymmetry. Final states in supersym- metry events at the LHC contain highly energetic jets and siz eable missing transverse energy. The additional requirement of events with highly energetic leptons simplifies the control of the backgrounds. This work presents results of a search for supe rsymmetry in the inclusive dilepton channel. Special emphasis is put on the search within the Gau ge-Mediated Symmetry Breaking (GMSB) scenario in which the supersymmetry breaking is medi ated via gauge fields. Statis- tically independent Control Regions for the dominant Stand ard Model backgrounds as well as ...

  2. The Silicon Vertex Tracker for the Heavy Photon Search Experiment

    CERN Document Server

    Adrian, Per Hansson

    2015-01-01

    The Heavy Photon Search (HPS) is a new, dedicated experiment at Thomas Jefferson National Accelerator Facility (JLab) to search for a massive vector boson, the heavy photon (a.k.a. dark photon, \\Aprimebold{}), in the mass range 20-500~MeV/c$^{2}$ and with a weak coupling to ordinary matter. An \\Aprimebold{} can be radiated from an incoming electron as it interacts with a charged nucleus in the target, accessing a large open parameter space where the \\Aprimebold{} is relatively long-lived, leading to displaced vertices. HPS searches for these displaced \\Aprimebold{} to e$^+$e$^-$ decays using actively cooled silicon microstrip sensors with fast readout electronics placed immediately downstream of the target and inside a dipole magnet to instrument a large acceptance with a relatively small detector. With typical particle momenta of 0.5-2~GeV/c, the low material budget of 0.7\\% $\\mathbf{X_0}$ per tracking layer is key to limiting the dominant multiple scattering uncertainty and allowing efficient separation of ...

  3. Search for inelastic dark matter with the CDMS II experiment

    CERN Document Server

    Ahmed, Z; Arrenberg, S; Bailey, C N; Balakishiyeva, D; Baudis, L; Bauer, D A; Brink, P L; Bruch, T; Bunker, R; Cabrera, B; Caldwell, D O; Cooley, J; Silva, E do Couto e; Cushman, P; Daal, M; DeJongh, F; Di Stefano, P; Dragowsky, M R; Duong, L; Fallows, S; Figueroa-Feliciano, E; Filippini, J; Fox, J; Fritts, M; Golwala, S R; Hall, J; Hennings-Yeomans, R; Hertel, S A; Holmgren, D; Hsu, L; Huber, M E; Kamaev, O; Kiveni, M; Kos, M; Leman, S W; Liu, S; Mahapatra, R; Mandic, V; McCarthy, K A; Mirabolfathi, N; Moore, D; Nelson, H; Ogburn, R W; Phipps, A; Pyle, M; Qiu, X; Ramberg, E; Rau, W; Razeti, M; Reisetter, A; Resch, R; Saab, T; Sadoulet, B; Sander, J; Schnee, R W; Seitz, D N; Serfass, B; Sundqvist, K M; Tarka, M; Wikus, P; Yellin, S; Yoo, J; Young, B A; Zhang, J

    2010-01-01

    Results are presented from a reanalysis of the entire five-tower data set acquired with the Cryogenic Dark Matter Search (CDMS II) experiment at the Soudan Underground Laboratory, with an exposure of 969 kg-days. The analysis window was extended to a recoil energy of 150 keV, and an improved surface-event background-rejection cut was defined to increase the sensitivity of the experiment to the inelastic dark matter (IDM) model. Three dark matter candidates were found between 25 keV and 150 keV. The probability to observe three or more background events in this energy range is 11%. Due to the occurrence of these events the constraints on the IDM parameter space are slightly less stringent than those from our previous analysis, which used a narrower energy window of 10-100 keV.

  4. Search for hidden particles with the SHiP experiment

    Energy Technology Data Exchange (ETDEWEB)

    Hagner, Caren; Bick, Daniel; Bieschke, Stefan; Ebert, Joachim; Schmidt-Parzefall, Walter [Universitaet Hamburg, Institut fuer Experimentalphysik, Luruper Chaussee 149, 22761 Hamburg (Germany)

    2016-07-01

    Many theories beyond the standard model predict long lived neutral (hidden) particles. There might be a whole Hidden Sector (HS) of weakly interacting particles, which cannot be detected in existing high energy experiments. The SHiP experiment (Search for Hidden Particles) requires a high intensity beam dump, which could be realized by a new facility at the CERN SPS accelerator. New superweakly interacting particles with masses below O(10) GeV could be produced in the beam dump and detected in a general purpose Hidden Sector (HS) detector. In addition there will be a dedicated tau neutrino subdetector. I present the major requirements and technical challenges for the HS detector and discuss how the HS can be accessed through several portals: neutrino portal, scalar portal, vector portal and many more.

  5. Geneva University: Dark matter Search with the CDMS experiment

    CERN Multimedia

    Université de Genève

    2011-01-01

    Geneva University Physics Department 24, quai Ernest-Ansermet CH-1211 Geneva 4 Tel: (022) 379 62 73 Fax: (022) 379 69 92   Wednesday 21 September 2011 PARTICLE PHYSICS SEMINAR at 17.00 hrs – Stückelberg Auditorium “ Dark matter Search with the CDMS experiment ” Par Dr. Sebastian Arrenberg, Université de Zürich The Cryogenic Dark Matter Search experiment (CDMS) employs a total of 30 germanium and silicon detectors at the Soudan Underground Laboratory to detect weakly interacting massive particles (WIMPs) via their scattering from the target nuclei. Previous CDMS results, released in December 2009, set the world leading limit on the spin-independent WIMP-nucleon cross section above WIMP masses of ~50 GeV/c2 assuming elastic scattering.  In a subsequent analysis we investigated the inelastic dark matter scenario which was proposed to reconcile the disagreement between the results of DAMA/LIBRA and other existing dark matter searc...

  6. The Cryogenic Dark Matter Search low ionization-threshold experiment

    Energy Technology Data Exchange (ETDEWEB)

    Basu Thakur, Ritoban [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2014-01-01

    Over 80 years ago we discovered the presence of Dark Matter in our universe. Endeavors in astronomy and cosmology are in consensus with ever improving precision that Dark Matter constitutes an essential 27% of our universe. The Standard Model of Particle Physics does not provide any answers to the Dark Matter problem. It is imperative that we understand Dark Matter and discover its fundamental nature. This is because, alongside other important factors, Dark Matter is responsible for formation of structure in our universe. The very construct in which we sit is defined by its abundance. The Milky Way galaxy, hence life, wouldn't have formed if small over densities of Dark Matter had not caused sufficient accretion of stellar material. Marvelous experiments have been designed based on basic notions to directly and in-directly study Dark Matter, and the Cryogenic Dark Matter Search (CDMS) experiment has been a pioneer and forerunner in the direct detection field. Generations of the CDMS experiment were designed with advanced scientific upgrades to detect Dark Matter particles of mass O(100) GeV/c2. This mass-scale was set primarily by predictions from Super Symmetry. Around 2013 the canonical SUSY predictions were losing some ground and several observations (rather hints of signals) from various experiments indicated to the possibility of lighter Dark Matter of mass O(10) GeV/c2. While the SuperCDMS experiment was probing the regular parameter space, the CDMSlite experiment was conceived to dedicatedly search for light Dark Matter using a novel technology. "CDMSlite" stands for CDMS - low ionization threshold experiment. Here we utilize a unique electron phonon coupling mechanism to measure ionization generated by scattering of light particles. Typically signals from such low energy recoils would be washed under instrumental noise. In CDMSlite via generation of Luke-Neganov phonons we can detect the small ionization energies, amplified in

  7. Final Results of the PICASSO Dark Matter Search Experiment

    CERN Document Server

    Behnke, E; Bhattacharjee, P; Dai, X; Das, M; Davour, A; Debris, F; Dhungana, N; Farine, J; Fines-Neuschild, M; Gagnebin, S; Giroux, G; Grace, E; Jackson, C M; Kamaha, A; Krauss, C B; Lafrenière, M; Laurin, M; Lawson, I; Lessard, L; Levine, I; Marlisov, D; Martin, J -P; Mitra, P; Noble, A J; Plante, A; Podviyanuk, R; Pospisil, S; Scallon, O; Seth, S; Starinski, N; Stekl, I; Wichoski, U; Zacek, V

    2016-01-01

    The PICASSO dark matter search experiment operated an array of 32 superheated droplet detectors containing 3.2 kg of C$_{4}$F$_{10}$ and collected an exposure of 231.4 kg days at SNOLAB between March 2012 and January 2014. We report on the final results of this experiment which includes for the first time the complete data set and improved analysis techniques including acoustic localization to allow fiducialization and removal of higher activity regions within the detectors. No signal consistent with dark matter was observed. We set limits for spin-dependent interactions on protons of $\\sigma_p^{SD}$ = 1.32 $\\times$ 10$^{-2}$ pb (90% C.L.) at a WIMP mass of 20 GeV/c$^{2}$. In the spin-independent sector we exclude cross sections larger than $\\sigma_p^{SI}$ = 4.86 $\\times$ 10$^{-5 }$ pb (90% C.L.) in the region around 7 GeV/c$^{2}$. The pioneering efforts of the PICASSO experiment have paved the way forward for a next generation detector incorporating much of this technology and experience into larger mass bub...

  8. A Comparison of Training Experience, Training Satisfaction, and Job Search Experiences between Integrated Vascular Surgery Residency and Traditional Vascular Surgery Fellowship Graduates.

    Science.gov (United States)

    Colvard, Benjamin; Shames, Murray; Schanzer, Andres; Rectenwald, John; Chaer, Rabih; Lee, Jason T

    2015-10-01

    The first 2 integrated vascular residents in the United States graduated in 2012, and in 2013, 11 more entered the job market. The purpose of this study was to compare the job search experiences of the first cohort of integrated 0 + 5 graduates to their counterparts completing traditional 5 + 2 fellowship programs. An anonymous, Web-based, 15-question survey was sent to all 11 graduating integrated residents in 2013 and to the 25 corresponding 5 + 2 graduating fellows within the same institution. Questions focused on the following domains: training experience, job search timelines and outcomes, and overall satisfaction with each training paradigm. Survey response was nearly 81% for the 0 + 5 graduates and 64% for the 5 + 2 graduates. Overall, there was no significant difference between residents and fellows in the operative experience obtained as measured by the number of open and endovascular cases logged. Dedicated research time during the entire training period was similar between residents and fellows. Nearly all graduates were extremely satisfied with their training and had positive experiences during their job searches with respect to starting salaries, numbers of offers, and desired practice type. More 0 + 5 residents chose academic and mixed practices over private practices compared with 5 + 2 fellowship graduates. Although longer term data are needed to understand the impact of the addition of 0 + 5 graduating residents to the vascular surgery work force, preliminary survey results suggest that both training paradigms (0 + 5 and 5 + 2) provide positive training experiences that result in excellent job search experiences. Based on the current and future need for vascular surgeons in the work force, the continued growth and expansion of integrated 0 + 5 vascular surgery residency positions as an alternative to traditional fellowship training is thus far justified. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. The AMS-02 Experiment and the Dark Matter Search

    CERN Document Server

    Masi, Nicolo

    AMS-02 is running after great scientific goals since one year and a half: a final setting up for dark matter searches has been achieved, allowing to study the so important antiparticle to particle ratios, which will probably be the first dark matter signals ever corroborated. Even if primary cosmic rays fluxes are subjected to a lot of uncertainties sources, some statements can be done and have been written down about dark matter properties: DM should be a heavy Majorana fermion or Spin 0 or 1 boson, with a mass from about 1 TeV to 10 TeV - unveiling a new TeV-ish search age - which could be able to originate antiparticle fluxes enhancements at high energies, both for positrons and antiprotons. All the observations, direct and indirect, point to these new paradigms or can be traced back to them quite easily. These enhancements perfectly fall into the research window of AMS-02, allowing the experiment to attack each today credible theory. Also an investigation of the Sommerfeld effect-associated dark boson wil...

  10. Detector Simulation and WIMP Search Analysis for the Cryogenic Dark Matter Search Experiment

    Energy Technology Data Exchange (ETDEWEB)

    McCarthy, Kevin [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2013-06-01

    Astrophysical and cosmological measurements on the scales of galaxies, galaxy clusters, and the universe indicate that 85% of the matter in the universe is composed of dark matter, made up of non-baryonic particles that interact with cross-sections on the weak scale or lower. Hypothetical Weakly Interacting Massive Particles, or WIMPs, represent a potential solution to the dark matter problem, and naturally arise in certain Standard Model extensions. The Cryogenic Dark Matter Search (CDMS) collaboration aims to detect the scattering of WIMP particles from nuclei in terrestrial detectors. Germanium and silicon particle detectors are deployed in the Soudan Underground Laboratory in Minnesota. These detectors are instrumented with phonon and ionization sensors, which allows for discrimination against electromagnetic backgrounds, which strike the detector at rates orders of magnitude higher than the expected WIMP signal. This dissertation presents the development of numerical models of the physics of the CDMS detectors, implemented in a computational package collectively known as the CDMS Detector Monte Carlo (DMC). After substantial validation of the models against data, the DMC is used to investigate potential backgrounds to the next iteration of the CDMS experiment, known as SuperCDMS. Finally, an investigation of using the DMC in a reverse Monte Carlo analysis of WIMP search data is presented.

  11. Supersymmetry Searches at the Compact Muon Solenoid (CMS Experiment, 2011

    Directory of Open Access Journals (Sweden)

    Koay S. A.

    2012-06-01

    Full Text Available The discovery/exclusion of Supersymmetric models for fundamental interactions of particles is one of the milestones targeted by the Large Hadron Collider (LHC, and in particular comprises of a large part of the physics program of the CMS experiment. Since the initial measurements using the 36 pb−1 of integrated luminosity delivered by the LHC in 2010, presently available results utilize about one fifth of the data delivered in 2011, i.e. in the ballpark of 1 fb−1, significantly extending the world limits placed on gluino and squark production signals. An overview of these analyses is presented, highlighting four that had been newly made public as of the date of this conference. The evidence for Supersymmetry (SUSY is still elusive, and a discussion follows as to where current searches have not yet probed, also pointing out where they might have difficulty ever probing without dedicated arrangements.

  12. Search for charmed hadrons in the OPERA experiment

    Science.gov (United States)

    Pastore, A.

    2015-05-01

    The OPERA experiment was designed to study muon neutrino to tau neutrino oscillations in appearance mode, using the CERN to Gran Sasso (CNGS) high energy neutrino beam 730 km far from the source. From 2008 to 2012, CNGS neutrinos interactions were recorded in the OPERA detector, which includes target units made of lead plates alternated with emulsion films and electronic tracker planes. The on-going analysis is aimed at the detection of short-lived particle decays occurring over distances of the order of 1 mm from the neutrino interaction point. It has allowed identifying charmed hadrons together with the tau lepton decay candidates that have established vμ → vτ oscillations with a significance of 4.2 σ. The procedure applied in OPERA to detect short-lived particle decays and its application to the search for charmed hadrons will be discussed here in detail.

  13. Event categories in the EDELWEISS WIMP search experiment

    CERN Document Server

    Benoît, A; Broniatowski, A; Chambon, B; Chapellier, M; Chardin, G; Charvin, P; De Jésus, M; Stefano, P D; Drain, D; Dumoulin, L; Garoche, P; Gascon, J; Goldbach, C; Gros, M H; Juillard, A; de Lesquen, A; L'Hôte, D; Mallet, L; Mangin, J F; Marnieros, S; Mirabolfathi, N; Miramonti, L; Mosca, L; Navick, X F; Nollez, G; Pari, P; Pécourt, S; Simon, E; Stern, M; Torre, J P

    2000-01-01

    Four categories of events have been identified in the EDELWEISS-I dark matterexperiment using germanium cryogenic detectors measuring simultaneously chargeand heat signals. These categories of events are interpreted as electron andnuclear interactions occurring in the volume of the detector, and electron andnuclear interactions occurring close to the surface of the detectors(10-20 mu-mof the surface). We discuss the hypothesis that low energy surface nuclearrecoils,which seem to have been unnoticed by previous WIMP searches, mayprovide an interpretation of the anomalous events recorded by the UKDMC andSaclay NaI experiments. The present analysis points to the necessity of takinginto account surface nuclear and electron recoil interactions for a reliableestimate of background rejection factors.

  14. Search for charmed hadrons in the OPERA experiment

    Directory of Open Access Journals (Sweden)

    Pastore A.

    2015-01-01

    Full Text Available The OPERA experiment was designed to study muon neutrino to tau neutrino oscillations in appearance mode, using the CERN to Gran Sasso (CNGS high energy neutrino beam 730 km far from the source. From 2008 to 2012, CNGS neutrinos interactions were recorded in the OPERA detector, which includes target units made of lead plates alternated with emulsion films and electronic tracker planes. The on-going analysis is aimed at the detection of short-lived particle decays occurring over distances of the order of 1 mm from the neutrino interaction point. It has allowed identifying charmed hadrons together with the tau lepton decay candidates that have established vμ → vτ oscillations with a significance of 4.2 σ. The procedure applied in OPERA to detect short-lived particle decays and its application to the search for charmed hadrons will be discussed here in detail.

  15. Search for proton decay in the Frejus experiment

    Science.gov (United States)

    Berger, C.; Hoffmann, A.; Raupach, F.; Tutas, J.; Schmitz, G.; Dudelzak, B.; Eschstruth, P.; Deuzet, G.; Jullian, S.; Lalanne, D.

    1985-01-01

    The status of the Frejus experiment and the preliminary results obtained in the search for nucleon decay are discussed. A modular, fine grain tracking calorimeter was installed in the Frejus laboratory in the period extending from October 1983 to May 1985. The 3300 cubic meter underground laboratory, located in the center of the Frejus tunnel in the Alps, is covered in the vertical direction by 1600 m of rocks (4400 m w.e.). The average number of atmospheric muons in the lab is 4.2 square meters per day. The 912 ton detector is made of 114 modules, each one including eight flash chamber and one Geiger vertical planes of (6 x 6) square meters dimensions. The flash chamber (and Geiger) planes are alternatively crossed to provide a 90 deg. stereo reconstruction. No candidate for the nucleon decay into charged lepton is found in the first sample of events.

  16. Supersymmetry Searches at the Compact Muon Solenoid (CMS) Experiment, 2011

    CERN Document Server

    Koay, S A

    2012-01-01

    The discovery/exclusion of Supersymmetric models for fundamental interactions of particles is one of the milestones targeted by the Large Hadron Collider (LHC), and in particular comprises of a large part of the physics program of the CMS experiment. Since the initial measurements using the 36\\ipb of integrated luminosity delivered by the LHC in 2010, presently available results utilize about one fifth of the data delivered in 2011, i.e. in the ballpark of 1\\ifb, significantly extending the world limits placed on gluino and squark production signals. An overview of these analyses is presented, highlighting four that had been newly made public as of the date of this conference. The evidence for Supersymmetry (SUSY) is still elusive, and a discussion follows as to where current searches have not yet probed, also pointing out where they might have difficulty ever probing without dedicated arrangements.

  17. Online Searching: Measures That Discriminate among Users with Different Types of Experiences.

    Science.gov (United States)

    Fenichel, Carol Hansen

    1981-01-01

    Describes a study conducted to identify the differences among the searches of users of online systems who have different amounts of overall experience, and the differences between the searches of persons with and without experience on the database being searched. Twenty-five references are cited. (FM)

  18. Searches for exotic interactions with the nEDM experiment

    CERN Document Server

    Bondar, Vira

    2016-01-01

    Ultracold neutrons were used to search for signals indicating the violation of Lorentz and CPT invariance or the existence of dark matter using the spectrometer to search for an electric dipole moment of the neutron.

  19. The North Carolina State University Libraries Search Experience: Usability Testing Tabbed Search Interfaces for Academic Libraries

    Science.gov (United States)

    Teague-Rector, Susan; Ballard, Angela; Pauley, Susan K.

    2011-01-01

    Creating a learnable, effective, and user-friendly library Web site hinges on providing easy access to search. Designing a search interface for academic libraries can be particularly challenging given the complexity and range of searchable library collections, such as bibliographic databases, electronic journals, and article search silos. Library…

  20. Axion searches with the EDELWEISS-II experiment

    CERN Document Server

    Armengaud, E; Augier, C; Benoit, A; Bergé, L; Bergmann, T; Blümer, J; Broniatowski, A; Brudanin, V; Camus, P; Cazes, A; Censier, B; Chapellier, M; Charlieux, F; Couëdo, F; Coulter, P; Cox, G A; de Boissière, T; De Jesus, M; Dolgorouky, Y; Drillien, A A; Dumoulin, L; Eitel, K; Filosofov, D; Fourches, N; Gascon, J; Gerbier, G; Gros, M; Hehn, L; Henry, S; Hervé, S; Heuermann, G; Holtzer, N; Humbert, V; Juillard, A; Kéfélian, C; Kleifges, M; Kluck, H; Kozlov, V; Kraus, H; Kudryavtsev, V A; Sueur, H Le; Mancuso, M; Marrache-Kikuchi, C; Marnieros, S; Menshikov, A; Navick, X-F; Nones, C; Olivieri, E; Pari, P; Paul, B; Piro, M C; Rigaut, O; Robinson, M; Rozov, S; Sanglard, V; Schmidt, B; Siebenborn, B; Tcherniakhovski, D; Tenconi, M; Vagneron, L; Walker, R J; Weber, M; Yakushev, E; Zhang, X

    2013-01-01

    We present new constraints on the couplings of axions and more generic axion-like particles using data from the EDELWEISS-II experiment. The EDELWEISS experiment, located at the Underground Laboratory of Modane, primarily aims at the direct detection of WIMPs using germanium bolometers. It is also sensitive to the low-energy electron recoils that would be induced by solar or dark matter axions. Using a total exposure of up to 448 kg.d, we searched for axion-induced electron recoils down to 2.5 keV within four scenarios involving different hypotheses on the origin and couplings of axions. We set a 95% CL limit on the coupling to photons $g_{A\\gamma}<2.13\\times 10^{-9}$ GeV$^{-1}$ in a mass range not fully covered by axion helioscopes. We also constrain the coupling to electrons, $g_{Ae} < 2.56\\times 10^{-11}$, similar to the more indirect solar neutrino bound. Finally we place a limit on $g_{Ae}\\times g_{AN}^{\\rm eff}<4.70 \\times 10^{-17}$, where $g_{AN}^{\\rm eff}$ is the effective axion-nucleon coupl...

  1. Phonon Sensor Dynamics for Cryogenic Dark Matter Search Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Yen, Jeffrey [Stanford Univ., CA (United States)

    2015-01-01

    Understanding the quasiparticle diffusion process inside sputtered aluminum (Al thin films (~ 0.1-1 μm is critical for the Cryogenic Dark Matter Search (CDMS experiment to further optimize its detectors to directly search for dark matter. An initial study with Al films was undertaken by our group ~ 20 years ago, but some important questions were not answered at the time. This thesis can be considered a continuation of that critical study. The CDMS experiment utilizes high purity silicon and germanium crystals to simultaneously measure ionization and phonons created by particle interactions. In addition to describing some of the rich physics involved in simultaneously detecting ionization and phonons with a CDMS detector, this thesis focuses on the detailed physics of the phonon sensors themselves, which are patterned onto CDMS detector surfaces. CDMS detectors use thin sputtered Al films to collect phonon energy when it propagates to the surfaces of the detector crystals. The phonon energy breaks Cooper pairs and creates quasiparticles (qps). These qps diffuse until they get trapped in an proximitized “overlap” region where lower-Tc tungsten films connect to the Al film. These tungsten films are the transition edge sensors (W-TESs CDMS uses to readout phonon signals. We performed a wide range of experiments using several sets of test devices designed and fabricated specifically for this work. The devices were used mostly to study quasiparticle (qp transport in Al films and qp transmission through Al/W interfaces. The results of this work are being used to optimize the design of detectors for SuperCDMS SNOLAB. This thesis is intended for CDMS collaborators who are interested in knowing more about the detailed fundamentals of how our phonon sensors work so they can take full advantage of their benefits. However, this work can also be read by general readers who are interested in particle detection using TES technology. This thesis contains eight chapters. The

  2. A methodology for simulated experiments in interactive search

    OpenAIRE

    2010-01-01

    Interactive information retrieval has received much attention in recent years, e.g. [7]. Furthermore, increased activity in developing interactive features in search systems used across existing popular Web search engines suggests that interactive systems are being recognised as a promising next step in assisting information search. One of the most challenging problems with interactive systems however remains evaluation.\\ud \\ud We describe the general specifications of a methodology for condu...

  3. Axion searches with the EDELWEISS-II experiment

    Energy Technology Data Exchange (ETDEWEB)

    Armengaud, E.; Boissière, T. de [CEA, Centre d' Etudes Saclay, IRFU, 91191 Gif-Sur-Yvette Cedex (France); Arnaud, Q.; Augier, C.; Benoit, A.; Cazes, A.; Censier, B.; Charlieux, F.; Jesus, M. De [IPNL, Université de Lyon, Université Lyon 1, CNRS/IN2P3, 4 rue E. Fermi 69622 Villeurbanne cedex (France); Benoit, A.; Camus, P. [CNRS-Néel, 25 Avenue des Martyrs, 38042 Grenoble cedex 9 (France); Bergé, L.; Broniatowski, A.; Chapellier, M.; Couëdo, F. [CSNSM, Université Paris-Sud, IN2P3-CNRS, bat 108, 91405 Orsay (France); Bergmann, T. [Karlsruhe Institute of Technology, Institut für Prozessdatenverarbeitung und Elektronik, 76021 Karlsruhe (Germany); Blümer, J.; Cox, G.A. [Karlsruhe Institute of Technology, Institut für Experimentelle Kernphysik, 76128 Karlsruhe (Germany); Brudanin, V. [Laboratory of Nuclear Problems, JINR, Joliot-Curie 6, 141980 Dubna, Moscow region (Russian Federation); Coulter, P., E-mail: claudia.nones@cea.fr, E-mail: thibault.main-de-boissiere@cea.fr, E-mail: eric.armengaud@cea.fr [University of Oxford, Department of Physics, Keble Road, Oxford OX1 3RH (United Kingdom); and others

    2013-11-01

    We present new constraints on the couplings of axions and more generic axion-like particles using data from the EDELWEISS-II experiment. The EDELWEISS experiment, located at the Underground Laboratory of Modane, primarily aims at the direct detection of WIMPs using germanium bolometers. It is also sensitive to the low-energy electron recoils that would be induced by solar or dark matter axions. Using a total exposure of up to 448 kg.d, we searched for axion-induced electron recoils down to 2.5 keV within four scenarios involving different hypotheses on the origin and couplings of axions. We set a 95 % CL limit on the coupling to photons g{sub Aγ} < 2.15 × 10{sup −9} GeV{sup −1} in a mass range not fully covered by axion helioscopes. We also constrain the coupling to electrons, g{sub Ae} < 2.59 × 10{sup −11}, similar to the more indirect solar neutrino bound. Finally we place a limit on g{sub Ae} × g{sub AN}{sup eff} < 4.82 × 10{sup −17}, where g{sub AN}{sup eff} is the effective axion-nucleon coupling for {sup 57}Fe. Combining these results we fully exclude the mass range 0.92 eV < m{sub A} < 80 keV for DFSZ axions and 5.78 eV < m{sub A} < 40 keV for KSVZ axions.

  4. New Architectures for Presenting Search Results Based on Web Search Engines Users Experience

    Science.gov (United States)

    Martinez, F. J.; Pastor, J. A.; Rodriguez, J. V.; Lopez, Rosana; Rodriguez, J. V., Jr.

    2011-01-01

    Introduction: The Internet is a dynamic environment which is continuously being updated. Search engines have been, currently are and in all probability will continue to be the most popular systems in this information cosmos. Method: In this work, special attention has been paid to the series of changes made to search engines up to this point,…

  5. Search for Neutrino Oscillations in Appearance Mode with the OPERA Experiment

    CERN Document Server

    Dzhatdoev, T A

    2014-01-01

    The present paper highlights the data analysis status of the OPERA experiment. The experiment was designed to perform the neutrino interactions analysis on event-by-event basis, and optimized to search for $\

  6. Searches for dark matter beyond mono-jets at the ATLAS experiment

    CERN Document Server

    Wang, Rui; The ATLAS collaboration

    2017-01-01

    Dark matter can be sought in complementary experiments: direct detection, indirect detection and colliders all contribute to a comprehensive set of searches for weakly interacting massive particles (WIMPs). This talk underlines the searches for Dark Matter by the ATLAS experiment in the context of this complementarity, using models that include a mediator particle between SM and DM.

  7. A search for near-infrared counterparts of two faint neutron star X-ray transients: XMMU J174716.1-281048 and SAX J1806.5-2215

    Science.gov (United States)

    Kaur, Ramanpreet; Wijnands, Rudy; Kamble, Atish; Cackett, Edward M.; Kutulla, Ralf; Kaplan, David; Degenaar, Nathalie

    2017-01-01

    We present our near-infrared (NIR) imaging observations of two neutron star low-mass X-ray binaries XMMU J174716.1-281048 and SAX J1806.5-2215 obtained using the PANIC instrument on the 6.5-metre Magellan telescope and the WIYN High-Resolution Infrared Camera instrument on the 3.5-metre WIYN telescope, respectively. Both sources are members of the class of faint to very faint X-ray binaries and undergo very long X-ray outburst, hence classified as `quasi-persistent X-ray binaries'. While XMMU J174716.1-281048 was active for almost 12 yr between 2003 and 2015, SAX J1806.5-2215 has been active for more than 5 yr now since 2011. From our observations, we identify two NIR stars consistent with the Chandra X-ray error circle of XMMU J174716.1-281048. The comparison of our observations with the United Kingdom Infrared Telescope (UKIRT) Galactic plane observations taken during the same outburst, colour-colour diagram analysis and spectral energy distribution suggest that both stars are probably a part of the field population and are likely high-mass stars. Hence possibly neither of the two stars is a true NIR counterpart. For the faint X-ray binary SAX J1806.5-2215 during its current outburst, we detected an NIR star in our K-band WIYN observations consistent with its Chandra error circle. The identified NIR star was not detected during the UKIRT observations taken during its quiescent state. The comparison of two observations suggests that there was an increase in flux by at least one magnitude of the detected star during our observations, and hence suggests the detection of the likely counterpart of SAX J1806.5-2215.

  8. A search for near-infrared counterparts of two faint neutron star X-ray transients : XMMU J174716.1-281048 and SAX J1806.5-2215

    Science.gov (United States)

    Kaur, Ramanpreet; Wijnands, Rudy; Kamble, Atish; Cackett, Edward M.; Kutulla, Ralf; Kaplan, David; Degenaar, Nathalie

    2016-09-01

    We present our near-infrared (NIR) imaging observations of two neutron star low mass X-ray binaries XMMU J174716.1-281048 and SAX J1806.5-2215 obtained using the PANIC instrument on the 6.5-meter Magellan telescope and the WHIRC instrument on the 3.5-meter WIYN telescope respectively. Both sources are members of the class of faint to very-faint X-ray binaries and undergo very long X-ray outburst, hence classified as `quasi persistent X-ray binaries'. While XMMU J174716.1-281048 was active for almost 12 years between 2003 and 2015, SAX J1806.5-2215 has been active for more than 5 years now since 2011. From our observations, we identify two NIR stars consistent with the Chandra X-ray error circle of XMMU J174716.1-281048. The comparison of our observations with the UKIRT Galactic plane observations taken during the same outburst, color-color diagram analysis and spectral energy distribution suggest that both stars are probably a part of the field population and are likely high mass stars. Hence possibly neither of the two stars is a true NIR counterpart. For the faint X-ray binary SAX J1806.5-2215 during its current outburst, we detected a NIR star in our K band WIYN observations consistent with its Chandra error circle. The identified NIR star was not detected during the UKIRT observations taken during its quiescent state. The comparison of two observations suggest that there was an increase in flux by at least one magnitude of the detected star during our observations, hence suggests the detection of the likely counterpart of SAX J1806.5-2215.

  9. Searches for Dark Matter with the ATLAS experiment

    CERN Document Server

    Lundberg, Olof; The ATLAS collaboration

    2015-01-01

    ATLAS is a multi-purpose detector aimed at fully exploiting the discovery potential of the proton-proton collisions at a center of mass energy of 8-14 TeV provided by CERN Large Hadron Collider. It is able to precisely identify and measure the properties of electrons, muons, photons, taus and hadronic jets. Thanks to an excellent hermeticity it is able to infer the production of neutrinos and dark matter particles from conservation of momentum using the missing energy observable. This talk will focus on the results of several dedicated searches for WIMP Dark Matter using the ATLAS detector. Among these searches are the so called "Mono-X" searches looking for signatures with large missing momentum recoiling against a gauge boson. We also present searches for decays of the Higgs boson into invisible states and searches for final states with missing transverse energy and third generation quarks. The results are interpreted in terms of Effective Field Theories as well as Simplified Models, and limits on nucleon-W...

  10. A framework for interpreting fast radio transients search experiments: application to the V-FASTR experiment

    CERN Document Server

    Trott, Cathryn M; Wayth, Randall B; Thompson, David R; Deller, Adam T; Brisken, Walter F; Wagstaff, Kiri L; Majid, Walid A; Burke-Spolaor, Sarah; Macquart, Jean-Pierre R; Palaniswamy, Divya

    2013-01-01

    We define a framework for determining constraints on the detection rate of fast transient events from a population of underlying sources, with a view to incorporating beam shape, frequency effects, scattering effects, and detection efficiency into the metric. We then demonstrate a method for combining independent datasets into a single event rate constraint diagram, using a probabilistic approach to the limits on parameter space. We apply this new framework to present the latest results from the V-FASTR experiment, a commensal fast transients search using the Very Long Baseline Array (VLBA). In the 20 cm band, V-FASTR now has the ability to probe the regions of parameter space of importance for the observed Lorimer and Keane fast radio transient candidates, by combining the information from observations with differing bandwidths, and properly accounting for the source dispersion measure, VLBA antenna beam shape, experiment time sampling, and stochastic nature of events. We then apply the framework to combine ...

  11. A search for sterile neutrinos at the MINOS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Pittam, Robert Neil [Univ. of Oxford (United Kingdom)

    2010-01-01

    MINOS is a long baseline neutrino oscillation experiment based at the Fermi National Accelerator Laboratory in Illinois, USA. The experiment was designed to study neutrino oscillation phenomena. The vμ beam produced by the NuMI beam facility at FNAL is used along with two functionally identical detectors. The Near Detector at FNAL and a Far Detector 735 km away in the Soudan Underground Laboratory in northern Minnesota. Comparison of the observed spectra of neutrinos at the two detectors provides the evidence for neutrino oscillations. This thesis presents work on the postulated phenomena of sterile neutrinos. Oscillations between active and sterile neutrinos will lead to a deficit in the expected rate of measured Neutral Current interactions at the Far Detector. A technique for selecting Neutral Current events utilizing an Artificial Neural Network is presented with resulting overall efficiency of 91.1% and purity of 66.0%. A method of predicting the expected Charged and Neutral Current energy spectra at the Far Detector given the data recorded at the Near Detector is presented. A model to search for oscillations between sterile and active neutrinos is developed. Sources of systematic uncertainty that can effect the results of the analysis are discussed. The analysis developed is applied to a Standard Model 3 flavour oscillation model as a cross check under the scenarios with and without ve appearance. The oscillation parameters measured by this model are Δm322 = (2.39-0.15+0.23) x 10-3 eV2 and θ23 = 0.727-0.11+0.22 for the no ve appearance result. An analysis of the resulting prediction reveals no evidence for active neutrino disappearance. The analysis is then performed using the 4 flavour neutrino oscillation model developed. Again this is done under the 2 scenarios of ve appearance and no ve appearance

  12. Searching for supersymmetry in compressed scenarios with the CMS experiment

    CERN Document Server

    Bainbridge, Robert

    2015-01-01

    Searches for supersymmetric models with a compressed mass spectrum are presented using data samples collected at a centre-of-mass energy of 8 TeV with the CMS detector at the LHC and corresponding to an integrated luminosity of 19.4$-$19.7~$fb^{-1}$. This class of model is challenging to detect experimentally, primarily due to low-momentum SM particles arising from decay chains involving SUSY particles of comparable mass. Various searches that are optimised for models involving the production of coloured sparticles or electroweakinos and a compressed mass spectrum are presented.

  13. A Framework for Interpreting Fast Radio Transients Search Experiments: Application to the V-FASTR Experiment

    Science.gov (United States)

    Trott, Cathryn M.; Tingay, Steven J.; Wayth, Randall B.; Thompson, David R.; Deller, Adam T.; Brisken, Walter F.; Wagstaff, Kiri L.; Majid, Walid A.; Burke-Spolaor, Sarah; Macquart, Jean-Pierre R.; Palaniswamy, Divya

    2013-04-01

    We define a framework for determining constraints on the detection rate of fast transient events from a population of underlying sources, with a view to incorporate beam shape, frequency effects, scattering effects, and detection efficiency into the metric. We then demonstrate a method for combining independent data sets into a single event rate constraint diagram, using a probabilistic approach to the limits on parameter space. We apply this new framework to present the latest results from the V-FASTR experiment, a commensal fast transients search using the Very Long Baseline Array (VLBA). In the 20 cm band, V-FASTR now has the ability to probe the regions of parameter space of importance for the observed Lorimer and Keane fast radio transient candidates by combining the information from observations with differing bandwidths, and properly accounting for the source dispersion measure, VLBA antenna beam shape, experiment time sampling, and stochastic nature of events. We then apply the framework to combine the results of the V-FASTR and Allen Telescope Array Fly's Eye experiments, demonstrating their complementarity. Expectations for fast transients experiments for the SKA Phase I dish array are then computed, and the impact of large differential bandwidths is discussed.

  14. SEARCH FOR DI-PHOTON RESONANCES WITH THE ATLAS EXPERIMENT

    CERN Document Server

    Mazza, Simone Michele; The ATLAS collaboration

    2016-01-01

    In this talk a search for a resonance in the two photons channel with the ATLAS detector at LHC will be reviewed. The presented analyses are based on 3.2 fb−1 of 13 TeV collision delivered by the LHC in 2015. Two searches were performed in this channel, one optimized for an hypothetical spin 0 particle and one optimized for a spin 2 Randall-Sundrum Graviton. The maximum deviation from the background only hypothesis has been observed around 750 GeV, the local significance was estimated. Also the global significance was evaluated taking into account the LEE effect. Updated limits for the two signal hypothesis are also reported.

  15. Tenure, Experience, Human Capital and Wages: A Tractable Equilibrium Search Model of Wage Dynamics

    OpenAIRE

    Bagger, Jesper; Fontaine, François; Postel-Vinay, Fabien; Robin, Jean-Marc

    2011-01-01

    We develop and estimate an equilibrium job search model of worker careers, allowing for human capital accumulation, employer heterogeneity and individual-level shocks. Career wage growth is decomposed into the contributions of human capital and job search, within and between jobs. Human capital accumulation is largest for highly educated workers, and both human capital accumulation and job search contribute to the observed concavity of wage-experience profiles. The contribution from job searc...

  16. Interplay and Characterization of Dark Matter Searches at Colliders and in Direct Detection Experiments

    CERN Document Server

    Malik, Sarah A.; Araujo, Henrique; Belyaev, A.; Bœhm, Céline; Brooke, Jim; Buchmueller, Oliver; Davies, Gavin; De Roeck, Albert; de Vries, Kees; Dolan, Matthew J.; Ellis, John; Fairbairn, Malcolm; Flaecher, Henning; Gouskos, Loukas; Khoze, Valentin V.; Landsberg, Greg; Newbold, Dave; Papucci, Michele; Sumner, Timothy; Thomas, Marc; Worm, Steven

    2015-01-01

    In this White Paper we present and discuss a concrete proposal for the consistent interpretation of Dark Matter searches at colliders and in direct detection experiments. Based on a specific implementation of simplified models of vector and axial-vector mediator exchanges, this proposal demonstrates how the two search strategies can be compared on an equal footing.

  17. Subject-Searching Experiences and Needs of Online Catalog Users: Implications for Library Classification.

    Science.gov (United States)

    Markey, Karen

    1985-01-01

    This paper describes an experiment in the use of Dewey Decimal Classification in online catalogs to introduce classed approach to subject searching of library collections, enhance subject terminology indexed in online catalog, and provide possibilities for search strategies not possible through alphabetical approach of subject headings and/or…

  18. Search for the exotic $\\Theta^+$ resonance in the NOMAD experiment

    CERN Document Server

    Samoylov, O; Autiero, D; Baldisseri, Alberto; Baldo-Ceolin, M; Banner, M; Bassompierre, G; Benslama, K; Besson, N; Bird, I; Blumenfeld, B; Bobisut, F; Bouchez, J; Boyd, S; Bueno, A; Bunyatov, S; Camilleri, L L; Cardini, A; Cattaneo, P W; Cavasinni, V; Cervera-Villanueva, A; Challis, R; Chukanov, A; Collazuol, G; Conforto, G; Conta, C; Contalbrigo, M; Cousins, R; Daniels, D; De Santo, A; Degaudenzi, H M; Del Prete, T; Di Lella, L; Dignan, T; Do Couto e Silva, E; Dumarchez, J; Ellis, M; Feldman, G J; Ferrari, R; Ferrère, D; Flaminio, V; Fraternali, M; Gaillard, J M; Gangler, E; Geiser, A; Geppert, D; Gibin, D; Gninenko, S; Godley, A; Gosset, J; Gouanère, M; Grant, A; Graziani, G; Guglielmi, A M; Gómez-Cadenas, J J; Gössling, C; Hagner, C; Hernando, J; Hubbard, D; Hurst, P; Hyett, N; Iacopini, E; Joseph, C; Juget, F; Kent, N; Kirsanov, M; Klimov, O; Kokkonen, J; Kovzelev, A; Krasnoperov, A V; La Rotonda, L; Lacaprara, S; Lachaud, C; Lakic, B; Lanza, A; Laveder, M; Letessier-Selvon, A A; Linssen, L; Ljubicic, A; Long, J; Lupi, A; Lyubushkin, V; Lévy, J M; Marchionni, A; Martelli, F; Mendiburu, J P; Meyer, J P; Mezzetto, M; Mishra, S R; Moorhead, G F; Méchain, X; Naumov, D; Nefedov, Yu; Nguyen-Mau, C; Nédélec, P; Orestano, D; Pastore, F; Peak, L S; Pennacchio, E; Pessard, H; Petti, R; Placci, A; Polesello, G; Pollmann, D; Polyarush, A Yu; Popov, B; Poulsen, C; Rebuffi, L; Rico, J; Riemann, P; Roda, C; Rubbia, André; Salvatore, F; Schahmaneche, K; Schmidt, B; Schmidt, T; Sconza, A; Sevior, M; Sillou, D; Soler, F J P; Sozzi, G; Steele, D; Stiegler, U; Stipcevic, M; Stolarczyk, T; Tareb-Reyes, M; Taylor, G N; Tereshchenko, V V; Toropin, A; Touchard, A M; Tovey, S N; Tran, M T; Tsesmelis, E; Ulrichs, J; Vacavant, L; Valdata-Nappi, M; Valuev, V; Vannucci, F; Varvell, K E; Veltri, M; Vercesi, V; Vidal-Sitjes, G; Vieira, J M; Vinogradova, T; Weber, F V; Weisse, T; Wilson, F F; Winton, L J; Yabsley, B D; Zaccone, Henri; Zuber, K; Zuccon, P

    2007-01-01

    A search for exotic Theta baryon via Theta -> proton +Ks decay mode in the NOMAD muon neutrino DIS data is reported. The special background generation procedure was developed. The proton identification criteria are tuned to maximize the sensitivity to the Theta signal as a function of xF which allows to study the Theta production mechanism. We do not observe any evidence for the Theta state in the NOMAD data. We provide an upper limit on Theta production rate at 90% CL as 2.13 per 1000 of neutrino interactions.

  19. Search for the exotic Θ+ resonance in the NOMAD experiment

    Science.gov (United States)

    Samoylov, O.; Naumov, D.; Cavasinni, V.; Astier, P.; Autiero, D.; Baldisseri, A.; Baldo-Ceolin, M.; Banner, M.; Bassompierre, G.; Benslama, K.; Besson, N.; Bird, I.; Blumenfeld, B.; Bobisut, F.; Bouchez, J.; Boyd, S.; Bueno, A.; Bunyatov, S.; Camilleri, L.; Cardini, A.; Cattaneo, P. W.; Cervera-Villanueva, A.; Challis, R.; Chukanov, A.; Collazuol, G.; Conforto, G.; Conta, C.; Contalbrigo, M.; Cousins, R.; Daniels, D.; Degaudenzi, H.; Del Prete, T.; de Santo, A.; Dignan, T.; di Lella, L.; Do Couto E Silva, E.; Dumarchez, J.; Ellis, M.; Feldman, G. J.; Ferrari, R.; Ferrère, D.; Flaminio, V.; Fraternali, M.; Gaillard, J.-M.; Gangler, E.; Geiser, A.; Geppert, D.; Gibin, D.; Gninenko, S.; Godley, A.; Gomez-Cadenas, J.-J.; Gosset, J.; Gößling, C.; Gouanère, M.; Grant, A.; Graziani, G.; Guglielmi, A.; Hagner, C.; Hernando, J.; Hubbard, D.; Hurst, P.; Hyett, N.; Iacopini, E.; Joseph, C.; Juget, F.; Kent, N.; Kirsanov, M.; Klimov, O.; Kokkonen, J.; Kovzelev, A.; Krasnoperov, A.; Lacaprara, S.; Lachaud, C.; Lakić, B.; Lanza, A.; La Rotonda, L.; Laveder, M.; Letessier-Selvon, A.; Levy, J.-M.; Linssen, L.; Ljubičić, A.; Long, J.; Lupi, A.; Lyubushkin, V.; Marchionni, A.; Martelli, F.; Méchain, X.; Mendiburu, J.-P.; Meyer, J.-P.; Mezzetto, M.; Mishra, S. R.; Moorhead, G. F.; Nédélec, P.; Nefedov, Y.; Nguyen-Mau, C.; Orestano, D.; Pastore, F.; Peak, L. S.; Pennacchio, E.; Pessard, H.; Petti, R.; Placci, A.; Polesello, G.; Pollmann, D.; Polyarush, A.; Poulsen, C.; Popov, B.; Rebuffi, L.; Rico, J.; Riemann, P.; Roda, C.; Rubbia, A.; Salvatore, F.; Schahmaneche, K.; Schmidt, B.; Schmidt, T.; Sconza, A.; Sevior, M.; Sillou, D.; Soler, F. J. P.; Sozzi, G.; Steele, D.; Stiegler, U.; Stipčević, M.; Stolarczyk, Th.; Tareb-Reyes, M.; Taylor, G. N.; Tereshchenko, V.; Toropin, A.; Touchard, A.-M.; Tovey, S. N.; Tran, M.-T.; Tsesmelis, E.; Ulrichs, J.; Vacavant, L.; Valdata-Nappi, M.; Valuev, V.; Vannucci, F.; Varvell, K. E.; Veltri, M.; Vercesi, V.; Vidal-Sitjes, G.; Vieira, J.-M.; Vinogradova, T.; Weber, F. V.; Weisse, T.; Wilson, F. F.; Winton, L. J.; Yabsley, B. D.; Zaccone, H.; Zuber, K.; Zuccon, P.

    2007-01-01

    A search for exotic Θ+ baryon via Θ+→p+K0 S decay mode in the NOMAD νμN data is reported. The special background generation procedure was developed. The proton identification criteria are tuned to maximize the sensitivity to the Θ+ signal as a function of xF which allows to study the Θ+ production mechanism. We do not observe any evidence for the Θ+ state in the NOMAD data. We provide an upper limit on Θ+ production rate at 90% CL as 2.13×10-3 per neutrino interaction.

  20. Searching of Double Electron Capture in the TGV Experiment

    CERN Document Server

    Brudanin, V B; Briançon, C; Benes, P; Vylov, T D; Gusev, K N; Egorov, V G; Klimenko, A A; Kovalenko, V E; Korolev, N A; Salamatin, A V; Timkov, V V; Cermák, P; Shirchenko, M V; Shitov, Yu A; Stekl, I

    2004-01-01

    The first investigations of the rare nuclear process - double electron capture of $^{106}$Cd have been performed using the low-background multi-detector spectrometer TGV-2 (Telescope Germanium Vertical). The preliminary results of calculations of experimental data obtained using 11.3 and 10 g of enriched $^{106}$Cd, and 14.5 g of natural Cd were presented. The sensitivity of T$_{1/2}^{EC/EC}>2.6\\cdot10^{19}$y (90\\% CL) was obtained for the searching of double electron capture of $^{106}$Cd ($0^{+} - 0^{+}$) in the investigation of natural Cd.

  1. Searching for neutrino oscillation parameters in long baseline experiments

    CERN Document Server

    Vihonen, Sampsa

    2016-01-01

    Developing neutrino astronomy requires a good understanding of the neutrino oscillations mechanism. The European strategy for neutrino oscillation physics sets a high priority on future long baseline neutrino experiments with the aim to measure the intrinsic parameters that govern the neutrino oscillations. In this work we take a look at the next generation of long baseline experiments and discuss their prospects in future research.

  2. A Novel Experiment to Search for the Decay μ→ eee

    Science.gov (United States)

    Scḧoning, Andŕe; Bachmann, Sebastian; Narayan, Rohin

    Design studies for an experiment searching for the lepton flavor violating decay μ→ eee are presented. The detector concept is based on thin layers of silicon sensors with fast readout. The aim of this experiment is to reach a sensitivity of B(μ→ eee) ≈ 10-16 corresponding to an improvement by a factor 10000 compared to previous experiments.

  3. The NEXT-100 experiment for neutrinoless double beta decay searches (Conceptual Design Report)

    OpenAIRE

    NEXT Collaboration; Álvarez, V.; Ball, M.; M. Batallé; Bayarri, J.; Borges, F. I. G.; Cárcel, S; Carmona, J.M.(Instituto de Física Nuclear y Altas Energías, Universidad de Zaragoza, Zaragoza, Spain); Castel, J.; Catalá, J. M.; Cebrián, S.; Cervera-Villanueva, A.; Chan, D.; Conde, C. A. N.; Dafni, T.

    2011-01-01

    We propose an EASY (Electroluminescent ApparatuS of high Yield) and SOFT (Separated Optimized FuncTion) time-projection chamber for the NEXT experiment, that will search for neutrinoless double beta decay (bb0nu) in Xe-136. Our experiment must be competitive with the new generation of bb0nu searches already in operation or in construction. This requires a detector with very good energy resolution (

  4. Status of Experiment NEUTRINO-4 Search for Sterile Neutrino

    CERN Document Server

    Serebrov, A; Samoilov, R; Fomin, A; Polyushkin, A; Zinoviev, V; Neustroev, P; Golovtsov, V; Chernyj, A; Zherebtsov, O; Martemyanov, V; Tarasenkov, V; Aleshin, V; Petelin, A; Izhutov, A; Tuzov, A; Sazontov, S; Ryazanov, D; Gromov, M; Afanasiev, V; Zaytsev, M; Chaikovskii, M

    2016-01-01

    In order to carry out research in the field of possible existence of a sterile neutrino the laboratory based on SM-3 reactor (Dimitrovgrad, Russia) was created to search for oscillations of reactor antineutrino. The prototype of a multi-section neutrino detector with liquid scintillator volume of 350 l was installed in the middle of 2015. It is a moveable inside the passive shielding detector, which can be set at distance range from 6 to 11 meters from the reactor core. Measurements of antineutrino flux at such short distances from the reactor core are carried out with moveable detector for the first time. The measurements with full-scale detector with liquid scintillator volume of 3 m^3 (5x10 sections) was started only in June, 2016. The today available data is presented in the article.

  5. Neutrino mass calorimetric searches in the MARE experiment

    CERN Document Server

    Nucciotti, A

    2010-01-01

    The international project ``Microcalorimeter Arrays for a Rhenium Experiment'' (MARE) aims at the direct and calorimetric measurement of the electron neutrino mass with sub-electronvolt sensitivity. Calorimetric neutrino mass experiments measure all the energy released in a beta decay except for the energy carried away by the neutrino, therefore removing the most severe systematic uncertainties which have plagued the traditional and, so far, more sensitive spectrometers. Calorimetric measurements are best realized exploiting the thermal detection technique. This approach uses thermal microcalorimeters whose absorbers contain a low transition energy Q beta decaying isotope. To date the two best options are 187Re and 163Ho. While the first beta decays, the latter decays via electron capture, but both have a Q value around 2.5 keV. The potential of using 187Re for a calorimetric neutrino mass experiment has been already demonstrated. On the contrary, no calorimetric spectrum of 163Ho has been so far measured wit...

  6. Search for extra-dimensions in the ATLAS experiment

    CERN Document Server

    Brochu, F M

    2004-01-01

    We report on the most recent simulation studies performed in the ATLAS experiment, looking for new phenomena in proton--proton collisions predicted by different models involving extra space dimensions to solve the hierarchy problem. All studies performed here used the fast, parametrized simulation of the ATLAS detector, ATLFAST.

  7. Searching for Dark Absorption with Direct Detection Experiments

    CERN Document Server

    Bloch, Itay M; Tobioka, Kohsaku; Volansky, Tomer; Yu, Tien-Tien

    2016-01-01

    We consider the absorption by bound electrons of dark matter in the form of dark photons and axion-like particles, as well as of dark photons from the Sun, in current and next-generation direct detection experiments. Experiments sensitive to electron recoils can detect such particles with masses between a few eV to more than 10 keV. For dark photon dark matter, we update a previous bound based on XENON10 data and derive new bounds based on data from XENON100 and CDMSlite. We find these experiments to disfavor previously allowed parameter space. Moreover, we derive sensitivity projections for SuperCDMS at SNOLAB for silicon and germanium targets, as well as for various possible experiments with scintillating targets (cesium iodide, sodium iodide, and gallium arsenide). The projected sensitivity can probe large new regions of parameter space. For axion-like particles, the same current direction detection data improves on previously known direct-detection constraints but does not bound new parameter space beyond...

  8. Composite dark matter and direct-search experiments

    CERN Document Server

    Wallemacq, Quentin

    2015-01-01

    We reinterpret the results of the direct searches for dark matter in terms of composite dark matter, i.e. dark matter particles that form neutral bound states, generically called dark atoms, either with ordinary particles, or with other dark matter particles. Three different scenarios are investigated: the O-helium scenario, milli- interacting dark matter and dark anti-atoms. In each of them, dark matter interacts sufficiently strongly with terrestrial matter to be stopped in it before reaching underground detectors. As they drift towards the center of the earth by gravity, these thermal dark atoms are radiatively captured by the atoms of the active medium of underground detectors, which causes the emission of photons that produce the signals through their interactions with the electrons of the medium. This provides a way of reinterpreting the results in terms of electron recoils instead of nuclear recoils. The detailed study of the interactions of O-helium with ordinary matter shows that it is not an accepta...

  9. Search for displaced lepton-jets with the ATLAS experiment

    CERN Document Server

    Sebastiani, Cristiano David; The ATLAS collaboration

    2017-01-01

    Several possible extensions of the Standard Model predict the existence of a dark sector that is weakly coupled to the visible one: i.e. the two sectors couple via the vector portal, where a dark photon with mass in the MeV to GeV range mixes kinetically with the SM photon. If the dark photon is the lightest state in the dark sector, it will decay to SM particles, mainly to leptons and possibly light mesons. Due to its weak interactions with the SM, it can have a non-negligible lifetime. At the LHC, these dark photons would typically be produced with large boost resulting in collimated jet-like structures containing pairs of leptons and/or light hadrons, the so-called lepton-jets (LJs). This work is focused on the search for “displaced LJs”, which are produced away from the interaction point and their constituents are limited to electrons, muons, and pions. The requested topology includes one or two LJs + leptons/jets/MET. The most recent ATLAS results based on samples collected at a center of mass energy...

  10. Microwave experiments simulating quantum search and directed transport in artificial graphene.

    Science.gov (United States)

    Böhm, Julian; Bellec, Matthieu; Mortessagne, Fabrice; Kuhl, Ulrich; Barkhofen, Sonja; Gehler, Stefan; Stöckmann, Hans-Jürgen; Foulger, Iain; Gnutzmann, Sven; Tanner, Gregor

    2015-03-20

    A series of quantum search algorithms have been proposed recently providing an algebraic speedup compared to classical search algorithms from N to √N, where N is the number of items in the search space. In particular, devising searches on regular lattices has become popular in extending Grover's original algorithm to spatial searching. Working in a tight-binding setup, it could be demonstrated, theoretically, that a search is possible in the physically relevant dimensions 2 and 3 if the lattice spectrum possesses Dirac points. We present here a proof of principle experiment implementing wave search algorithms and directed wave transport in a graphene lattice arrangement. The idea is based on bringing localized search states into resonance with an extended lattice state in an energy region of low spectral density-namely, at or near the Dirac point. The experiment is implemented using classical waves in a microwave setup containing weakly coupled dielectric resonators placed in a honeycomb arrangement, i.e., artificial graphene. Furthermore, we investigate the scaling behavior experimentally using linear chains.

  11. Nanohertz gravitational wave searches with interferometric pulsar timing experiments.

    Science.gov (United States)

    Tinto, Massimo

    2011-05-13

    We estimate the sensitivity to nano-Hertz gravitational waves of pulsar timing experiments in which two highly stable millisecond pulsars are tracked simultaneously with two neighboring radio telescopes that are referenced to the same timekeeping subsystem (i.e., "the clock"). By taking the difference of the two time-of-arrival residual data streams we can exactly cancel the clock noise in the combined data set, thereby enhancing the sensitivity to gravitational waves. We estimate that, in the band (10(-9)-10(-8))  Hz, this "interferometric" pulsar timing technique can potentially improve the sensitivity to gravitational radiation by almost 2 orders of magnitude over that of single-telescopes. Interferometric pulsar timing experiments could be performed with neighboring pairs of antennas of the NASA's Deep Space Network and the forthcoming large arraying projects.

  12. Search for New Physics in reactor and accelerator experiments

    Science.gov (United States)

    Di Iura, A.; Girardi, I.; Meloni, D.

    2016-01-01

    We consider two scenarios of New Physics: the Large Extra Dimensions (LED), where sterile neutrinos can propagate in a (4+d) -dimensional space-time, and the Non Standard Interactions (NSI), where the neutrino interactions with ordinary matter are parametrized at low energy in terms of effective flavour-dependent complex couplings \\varepsilon_{αβ} . We study how these models have an impact on oscillation parameters in reactor and accelerator experiments.

  13. Direct Dark Matter Search with the XENON100 Experiment

    Science.gov (United States)

    Mei, Yuan

    Dark matter, a non-luminous, non-baryonic matter, is thought to constitute 23 % of the matter-energy components in the universe today. Except for its gravitational effects, the existence of dark matter has never been confirmed by any other means and its nature remains unknown. If a hypothetical Weakly Interacting Massive Particle (WIMP) were in thermal equilibrium in the early universe, it could have a relic abundance close to that of dark matter today, which provides a promising particle candidate of dark matter. Minimal Super-Symmetric extensions to the standard model predicts a stable particle with mass in the range 10 GeV/c2 to 1000 GeV/c2, and spin-independent cross-section with ordinary matter nucleon sigmax power of liquid xenon, as well as a 99 kg liquid xenon active veto, the electromagnetic radiation background is greatly suppressed. By utilizing the difference of (S2/S1) between electronic recoil and nuclear recoil, the expected WIMP signature, a small nuclear recoil energy deposition, could be discriminated from electronic recoil background with high efficiency. XENON100 achieved the lowest background rate (< 2.2 x 10--2 events/kg/day/keV) in the dark matter search region (< 40 keV) among all direct dark matter detectors. With 11.2 days of data, XENON100 already sets the world's best spin-independent WIMP-nucleon cross-section limit of 2.7 x 10--44 cm2 at WIMP mass 50 GeV/c 2. With 100.9 days of data, XENON100 excludes WIMP-nucleon cross-section above 7.0 x 10--45 cm2 for a WIMP mass of 50 GeV/c2 at 90% confidence level.

  14. Searches for h(125) properties beyond the Standard Model at the CMS experiment

    CERN Document Server

    Lenz, Teresa

    2017-01-01

    The discovered Higgs boson with a mass of 125\\,GeV exhibits properties which are all in agreement with Standard Model predictions. However, the corresponding measurements still allow for a considerable non-Standard Model behavior of the h(125). Beyond Standard Model properties can show up in non-Standard Model decays of the h(125) or in anomalous couplings of the Higgs boson. This article presents four different analyses done at the CMS experiment with 2012 and 2016 data that search for properties of the discovered Higgs boson beyond the Standard Model. These include a search for lepton flavor violating Higgs decays, a search for decays of the h(125) to light Higgs bosons, a search for anomalous contributions to the Higgs trilinear self-coupling, and finally a search for anomalous couplings of the h(125) to vector bosons.

  15. The next generation of $\\mu\\ -> e \\gamma$ and $\\mu\\ -> 3e$ CLFV search experiments

    CERN Document Server

    Cheng, Chih-hsiang; Hitlin, David G

    2013-01-01

    We explore the possibilities for extending the sensitivity of current searches for the charged lepton flavor violating decays $\\mu\\ -> e \\gamma$ and $\\mu\\ -> eee$. A future facility such as Project X at Fermilab could provide a much more intense stopping $\\mu^+$ beam, facilitating more sensitive searches, but improved detectors will be required as well. Current searches are limited by accidental and physics backgrounds, as well as by the total number of stopped muons. One of the limiting factors in current detectors for $\\mu\\ -> e \\gamma$ searches is the photon energy resolution of the calorimeter. We present a new fast Monte Carlo simulation of a conceptual design of a new experimental concept that detects converted $e^+e^-$ pairs from signal photons, taking advantage of the improved energy resolution of a pair spectrometer based on a silicon charged particle tracker. We also study a related detector design for a next generation $\\mu\\to eee$ search experiment.

  16. Magnetic Monopole Search at high altitude with the SLIM experiment

    CERN Document Server

    Balestra, S; Cozzi, M; Errico, M; Fabbri, F; Giacomelli, G; Giacomelli, R; Giorgini, M; Kumar, A; Manzoor, S; McDonald, J; Mandrioli, G; Marcellini, S; Margiotta, A; Medinaceli, E; Patrizii, L; Pinfold, J L; Popa, V; Qureshi, I E; Saavedra, O; Sahnoun, Z; Sirri, G; Spurio, M; Togo, V; Velarde, A; Zanini, A

    2008-01-01

    The SLIM experiment was a large array of nuclear track detectors located at the Chacaltaya high altitude Laboratory (5230 m a.s.l.). The detector was in particular sensitive to Intermediate Mass Magnetic Monopoles, with masses 10^5 < M <10^{12} GeV. From the analysis of the full detector exposed for more than 4 years a flux upper limit of 1.3 x 10^{-15} cm^{-2} s^{-1} sr^{-1} for downgoing fast Intermediate Mass Monopoles was established at the 90% C.L.

  17. Dark matter searches with the CDMS II experiment

    Energy Technology Data Exchange (ETDEWEB)

    Saab, T. [Department of Physics, University of Florida, Gainesville, FL 32611 (United States); Collaboration: CDMS Collaboration

    2014-06-24

    The CDMS II experiment ran between 2003 and 2009. A total of 30 germanium and silicon ZIP detectors were operated, producing a high quality set of data that has been analyzed for evidence of and placed leading constraints on standard, low-mass, electron-recoil, and annually modulating WIMP interactions. This article will describe the general operation principles behind the CDMS detectors, report on the results of major Ge and Si detector analyses, and describe the current and future activities of the SuperCDMS program.

  18. Direct Dark Matter Search with the CRESST II Experiment

    CERN Document Server

    Schieck, J; Bento, A; Bucci, C; Canonica, L; Defay, X; Erb, A; Feilitzsch, F v; Iachellini, N Ferreiro; Gorla, P; Guetlein, A; Hauff, D; Jochum, J; Kiefer, M; Kluck, H; Kraus, H; Lanfranchi, J-C; Loebell, J; Mancuso, M; Muenster, A; Pagliarone, C; Petricca, F; Potzel, W; Pröbst, F; Puig, R; Reindl, F; Schaeffner, K; Schoenert, S; Seidel, W; Stahlberg, M; Stodolsky, L; Strandhagen, C; Strauss, R; Tanzke, A; Thi, H H Trinh; Turkoglu, C; Uffinger, M; Ulrich, A; Usherov, I; Wawoczny, S; Willers, M; Wueustrich, M; Zoeller, A

    2016-01-01

    The quest for the particle nature of dark matter is one of the big open questions of modern physics. A well motivated candidate for dark matter is the so-called WIMP - a weakly interacting massive particle. Recently several theoretically well-motivated models with dark matter candidates in a mass region below the WIMP mass-scale gained also a lot of interest, theoretically and experimentally. The CRESST II experiment located at the Gran Sasso laboratory in Italy is optimised for the detection of the elastic scattering of these low-mass dark matter particles with ordinary matter. We show the results obtained with an improved detector setup with increased radio purity and enhanced background rejection and the results obtained with a dedicated low-threshold analysis of a single conventional detector module. The limit achieved is the most stringent limit achieved for direct dark matter experiments in the mass region below 1.8 GeV/$c^{2}$. We will discuss the expected performance for new small CRESST-type detector...

  19. A NEW EXPERIMENT SEARCHING FOR DARK MATTER AT CERN

    CERN Multimedia

    2016-01-01

    The NA64 experiment started operations at CERN’s North Area earlier this year. It uses a unique setup to hunt down a specific type of dark matter particle called the dark photon. Some theories suggest that dark matter consists of a family of new particles and forces. In addition to gravity, dark-matter particles could interact with visible matter through a new force, which has so far escaped detection. Just as the electromagnetic force is carried by the photon, this dark force is thought to be transmitted by a particle called the dark photon. It is predicted to have a subtle interaction (a “mixing”, in particle-physics jargon) with the regular photon and therefore act as a mediator between visible and dark matter. CERN’s NA64 experiment looks for signatures of this visible-dark interaction using a simple but powerful physics concept: the conservation of energy. A beam of electrons coming from the Super Proton Synchrotron accelerator, whose initial energy is very precisely known (100 G

  20. A Sterile-Neutrino Search with the MINOS Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, Philip [Univ. of Oxford (United Kingdom)

    2010-01-01

    The MINOS experiment is a long-baseline neutrino oscillation experiment in the the NuMI beamline at Fermilab, USA. Using a near detector at 1 km distance from the neutrino production target, and a far detector at 735 km from the target, it is designed primarily to measure the disappearance of muon neutrinos. This thesis presents an analysis using MINOS data of the possibility of oscil- lation of the neutrinos in the NuMI beam to a hypothetical sterile flavour, which would have no Standard Model couplings. Such oscillations would result in a deficit in the neutral current interaction rate in the MINOS far detector relative to the expectation derived from the near detector data. The method used to identify neutral current and charged current events in the MINOS detectors is described and a new method of predicting and fitting the far detector spectrum presented, along with the effects of systematic uncertainties on the sterile neutrino oscillation analysis. Using this analysis, the fraction fs of the disappearing neutrinos that go to steriles is constrained to be below 0.15 at the 90% confidence level in the absence of electron neutrino appearance in the NuMI beam. With electron appearance at the CHOOZ limit, fs < 0.41 at 90% C.L.

  1. Resonance Search for a Heavy Photon in the 2015 Engineering Run Data of the Heavy Photon Search Experiment

    Science.gov (United States)

    Moreno, Omar; Heavy Photon Search Collaboration

    2017-01-01

    The Heavy Photon Search (HPS) experiment at Jefferson Lab is searching for a new U(1) vector boson (``heavy photon'',``dark photon'' or A') in the mass range of 20-500 MeV/c2. An A' in this mass range is theoretically favorable and may also mediate dark matter interactions. The A' couples to the ordinary photon through kinetic mixing, which induces their coupling to electric charge. Since heavy photons couple to electrons, they can be produced through a process analogous to bremsstrahlung, subsequently decaying to an e+e- , which can be observed as a narrow resonance above the dominant QED trident background. For suitably small couplings, heavy photons travel detectable distances before decaying, providing a second signature. Using the CEBAF electron beam at Jefferson Lab incident on a thin tungsten target, along with a compact, large acceptance forward spectrometer consisting of a silicon vertex tracker and lead tungstate electromagnetic calorimeter, HPS is accessing unexplored regions in the mass-coupling phase space. The HPS engineering run took place in spring of 2015 using a 1.056 GeV, 50 nA beam and collected 1165 nb-1 (7.29 mC) of data. This talk will present the results of a resonance search for a heavy photon using the engineering run data.

  2. An Experience Oriented-Convergence Improved Gravitational Search Algorithm for Minimum Variance Distortionless Response Beamforming Optimum.

    Directory of Open Access Journals (Sweden)

    Soodabeh Darzi

    Full Text Available An experience oriented-convergence improved gravitational search algorithm (ECGSA based on two new modifications, searching through the best experiments and using of a dynamic gravitational damping coefficient (α, is introduced in this paper. ECGSA saves its best fitness function evaluations and uses those as the agents' positions in searching process. In this way, the optimal found trajectories are retained and the search starts from these trajectories, which allow the algorithm to avoid the local optimums. Also, the agents can move faster in search space to obtain better exploration during the first stage of the searching process and they can converge rapidly to the optimal solution at the final stage of the search process by means of the proposed dynamic gravitational damping coefficient. The performance of ECGSA has been evaluated by applying it to eight standard benchmark functions along with six complicated composite test functions. It is also applied to adaptive beamforming problem as a practical issue to improve the weight vectors computed by minimum variance distortionless response (MVDR beamforming technique. The results of implementation of the proposed algorithm are compared with some well-known heuristic methods and verified the proposed method in both reaching to optimal solutions and robustness.

  3. Search for sterile neutrinos with the SOX experiment

    Science.gov (United States)

    Caminata, A.; Agostini, M.; Altenmüller, K.; Appel, S.; Bellini, G.; Benziger, J.; Berton, N.; Bick, D.; Bonfini, G.; Bravo, D.; Caccianiga, B.; Calaprice, F.; Cavalcante, P.; Chepurnov, A.; Choi, K.; Cribier, M.; D'Angelo, D.; Davini, S.; Derbin, A.; Di Noto, L.; Drachnev, I.; Durero, M.; Empl, A.; Etenko, A.; Farinon, S.; Fischer, V.; Fomenko, K.; Franco, D.; Gabriele, F.; Gaffiot, J.; Galbiati, C.; Ghiano, C.; Giammarchi, M.; Goeger-Neff, M.; Goretti, A.; Gromov, M.; Hagner, C.; Houdy, Th.; Hungerford, E.; Ianni, Aldo; Ianni, Andrea; Jonquères, N.; Jedrzejczak, K.; Kaiser, M.; Kobychev, V.; Korablev, D.; Korga, G.; Kornoukhov, V.; Kryn, D.; Lachenmaier, T.; Lasserre, T.; Laubenstein, M.; Lehnert, B.; Link, J.; Litvinovich, E.; Lombardi, F.; Lombardi, P.; Ludhova, L.; Lukyanchenko, G.; Machulin, I.; Manecki, S.; Maneschg, W.; Marcocci, S.; Maricic, J.; Mention, G.; Meroni, E.; Meyer, M.; Miramonti, L.; Misiaszek, M.; Montuschi, M.; Mosteiro, P.; Muratova, V.; Musenich, R.; Neumair, B.; Oberauer, L.; Obolensky, M.; Ortica, F.; Otis, K.; Pagani, L.; Pallavicini, M.; Papp, L.; Perasso, L.; Pocar, A.; Ranucci, G.; Razeto, A.; Re, A.; Romani, A.; Roncin, R.; Rossi, N.; Schönert, S.; Scola, L.; Semenov, D.; Simgen, H.; Skorokhvatov, M.; Smirnov, O.; Sotnikov, A.; Sukhotin, S.; Suvorov, Y.; Tartaglia, R.; Testera, G.; Thurn, J.; Toropova, M.; Unzhakov, E.; Veyssière, C.; Vivier, M.; Vogelaar, R. B.; von Feilitzsch, F.; Wang, H.; Weinz, S.; Winter, J.; Wojcik, M.; Wurm, M.; Yokley, Z.; Zaimidoroga, O.; Zavatarelli, S.; Zuber, K.; Zuzel, G.

    2016-01-01

    In the recent years, the Borexino detector has proven its outstanding performances in detecting neutrinos and antineutrinos in the low energy regime. Consequently, it is an ideal tool to investigate the existence of sterile neutrinos, whose presence has been suggested by several anomalies over the past two decades. The SOX ( Short distance neutrino Oscillations with boreXino) project will investigate the presence of sterile neutrinos placing a neutrino and an antineutrino sources in a location under the detector foreseen for this purpose since the construction of Borexino. Interacting in the detector active volume, each beam would create a well detectable spatial wave pattern in case of oscillation of neutrino or antineutrino in a sterile state. Otherwise, the experiment will set a very stringent limit on the existence of a sterile state.

  4. Search for GUT magnetic monopoles and nuclearites with the MACRO experiment

    CERN Document Server

    Ambrosio, M; Auriemma, G; Bakari, D; Baldini, A; Barbarino, G C; Barish, B C; Battistoni, G; Becherini, Y; Bellotti, R; Bemporad, C; Bernardini, P; Bilokon, H; Bloise, C; Bower, C; Brigida, M; Bussino, S; Cafagna, F; Calicchio, M; Campana, D; Carboni, M; Caruso, R; Cecchini, S; Cei, F; Chiarella, V; Chiarusi, T; Choudhary, B C; Coutu, S; Cozzi, M; De Cataldo, G; De Marzo, C; De Mitri, I; De Vincenzi, M; Dekhissi, H; Derkaoui, J; Di Credico, A; Erriquez, O; Favuzzi, C; Forti, C; Fusco, P; Giacomelli, G; Giannini, G; Giglietto, N; Giorgini, M; Grassi, M; Grillo, A; Guarino, F; Gustavino, C; Habig, A; Hanson, K; Heinz, R; Katsavounidis, E; Katsavounidis, I; Kearns, E; Kim, H; Kumar, A; Kyriazopoulou, S; Lamanna, E; Lane, C; Larocci, E; Levin, D S; Lipari, P; Longley, N P; Longo, M J; Loparco, F; Maarou, F; Mancarella, G; Mandrioli, G; Manzoor, S; Margiotta, A; Marini, A; Martello, D; Marzari-Chiesa, A; Matteuzzi, D; Mazziotta, M N; Michael, D G; Monacelli, P; Montaruli, T; Monteno, M; Mufson, S; Musser, J; Nicolò, D; Nolty, R; Orth, C; Osteria, G; Palamara, O; Patera, V; Patrizii, L; Pazzi, R; Peck, C W; Perrone, L; Petrera, S; Pistilli, P; Popa, V; Rainó, A; Reynoldson, J; Ronga, F; Rrhioua, A; Satriano, C; Scapparone, E; Scholberg, K; Sciubba, A; Serra, P; Sioli, M; Sirri, G; Sitta, M; Spinelli, P; Spinetti, M; Spurio, M; Steinberg, R; Stone, J L; Sulak, L R; Surdo, A; Tarle, G; Togo, V; Vakili, M; Walter, C W; Webb, R; 10.1016/S1350-4487(03)00140-9

    2003-01-01

    We present the final results obtained by the MACRO experiment in the search for GUT magnetic monopoles and nuclearites. Several searches were performed with different subdetectors, i.e. scintillation counters, limited streamer tubes and nuclear track detectors. No magnetic monopole or nuclearite candidates were found. The MACRO upper limit to the local flux of GUT magnetic monopoles is at the level of 1.4*10/sup -16/ cm/sup -2/s/sup -1/sr/sup -1/.

  5. Research Proposal for an Experiment to Search for the Decay {\\mu} -> eee

    CERN Document Server

    Blondel, A; Pohl, M; Bachmann, S; Berger, N; Kiehn, M; Schöning, A; Wiedner, D; Windelband, B; Eckert, P; Schultz-Coulon, H -C; Shen, W; Fischer, P; Perić, I; Hildebrandt, M; Kettle, P -R; Papa, A; Ritt, S; Stoykov, A; Dissertori, G; Grab, C; Wallny, R; Gredig, R; Robmann, P; Straumann, U

    2013-01-01

    We propose an experiment (Mu3e) to search for the lepton flavour violating decay mu+ -> e+e-e+. We aim for an ultimate sensitivity of one in 10^16 mu-decays, four orders of magnitude better than previous searches. This sensitivity is made possible by exploiting modern silicon pixel detectors providing high spatial resolution and hodoscopes using scintillating fibres and tiles providing precise timing information at high particle rates.

  6. Search for Solar Axions with the CAST-Experiment

    CERN Document Server

    Vogel, J.; Aune, S.; Autiero, D.; Barth, K.; Belov, A.; Beltran, B.; Borghi, S.; Bourlis, G.; Boydag, F. S.; Brauninger, H.; Carmona, J.; Cebrian, S.; Cetin, S. A.; Collar, J.I.; Dafni, T.; Davenport, M.; Di Lella, L.; Dogan, O. B.; Elefheriadis, C.; Elias, N.; Fanourakis, G.; Ferrer-Ribas, E.; Fisher, H.; Franz, J.; Galan, J.; Geralis, T.; Giomataris, I.; Gninenko, S.; Gomez, H.; Hasinoff, M.; Heinsius, H.; Hikmet, I.; Hoffmann, D. H. H.; Irastorza, I. G.; Jacoby, J.; Jakovcic, K.; Kang, D.; Konigsmann, K.; Kotthaus, R.; Krcmar, M.; Kousouris, K.; Kuster, M.; Lakic, B.; Lasseur, C.; Liolios, A.; Ljubicic, A.; Lutz, G.; Luzon, G.; Miller, D.; Morales, J.; Niinikoski, T.; Nordt, A.; Ortiz, A.; Papaevangelou, T.; Pivovaroff, M.; Placci, A.; Raffelt, G.; Riege, H.; Rodriguez, A.; Ruz, J.; Savvidis, I.; Semertzidis, Y.; Serpico, P.; Soufli, R.; Stewart, L.; Tzamarias, S.; Van Bibber, K.; Villar, J.; Walckiers, L.; Zioutas, K.; Morales, A.

    2008-01-01

    Solar axions can be produced in the Sun via the so-called Primakoff effect. The CERN Axion Solar Telescope (CAST) uses an LHC prototype magnet of about 9 T to reconvert these axions into photons. The magnet is able to follow the Sun for about 3 hours per day. Three different X-Ray detectors are mounted on its ends to detect photons from axion-to-photon conversion: a Time Projection Chamber (TPC), a MICROMEGAS (MICROMEsh GAseous Structure) and a Charge Coupled Device (CCD). For the CCD an X-ray focusing device is used to improve the signal-to-background ratio significantly. With the completion of CAST'S first phase, the current limits on the coupling constant gaγ for axion masses up to 0.02 eV have been improved. In its second phase, CAST extends the axion mass range by filling the magnet with a buffer gas. Masses up to about 0.4 eV have already been covered and thus the experiment is entering the regions favored by axion models. This paper will present the status of CAST'S second phase.

  7. Experiments concerning the automated search for elegant proofs

    Energy Technology Data Exchange (ETDEWEB)

    Wos, L.

    1997-07-01

    The research reported in this technical report was spawned by the request to find an elegant proof (of a theorem from Boolean algebra) to replace the known proof consisting of 816 deduced steps. The request was met by finding a proof consisting of 100 deduced steps. The methodology used to obtain the far shorter proof is presented in detail through a sequence of experiments. Although clearly not an algorithm, the methodology is sufficiently general to enable its use for seeking elegant proofs regardless of the domain of study. The methodology relies heavily on the assistance of McCune`s automated reasoning program OTTER. Of the aspects of proof elegance, the main focus here is on proof length, with brief attention paid to the type of term present, the number of variables required, and the complexity of deduced steps. The methodology is iterative, relying heavily on the use of three strategies: the resonance strategy, the hot list strategy, and McCune`s ratio strategy. To provide some insight regarding the value of the methodology, the author discusses its successful application to other problems from Boolean algebra and to problems from lattice theory. Research suggestions and challenges are also offered.

  8. Galaxy Strategy for LIGO-Virgo Gravitational Wave Counterpart Searches

    OpenAIRE

    Gehrels, N.; Cannizzo, J. K.; Kanner, J.; Kasliwal, M.M.; Nissanke, S.; Singer, L. P.

    2016-01-01

    In this work we continue a line of inquiry begun in Kanner et al. which detailed a strategy for utilizing telescopes with narrow fields of view, such as the Swift X-ray Telescope (XRT), to localize gravity wave (GW) triggers from LIGO/Virgo. If one considers the brightest galaxies that produce ~50% of the light, then the number of galaxies inside typical GW error boxes will be several tens. We have found that this result applies both in the early years of Advanced LIGO when the range is small...

  9. $\\gamma$-Ray Burster Counterparts HST Blue and Ultraviolet Data

    CERN Document Server

    Schaefer, B E; Hurley, K; Laros, J G; Schaefer, Bradley E.; Cline, Thomas; Hurley, Kevin; Laros, John

    1997-01-01

    The surest solution of the Gamma Ray Burst (GRB) mystery is to find an unambiguous low-energy quiescent counterpart. However, to date no reasonable candidates have been identified in the x-ray, optical, infrared, or radio ranges. The Hubble Space Telescope (HST) has now allowed for the first deep ultraviolet searches for quiescent counterparts. This paper reports on multiepoch ultraviolet searches of five GRB positions with HST. We found no sources with significant ultraviolet excesses, variability, parallax, or proper motion in any of the burst error regions. In particular, we see no sources similar to that proposed as a counterpart to the GRB970228. While this negative result is disappointing, it still has good utility for its strict limits on the no-host-galaxy problem in cosmological models of GRBs. For most cosmological models (with peak luminosity 6X10^50 erg/s), the absolute B magnitude of any possible host galaxy must be fainter than -15.5 to -17.4. These smallest boxes for some of the brightest burst...

  10. Alpenglow. A signature for chameleons in axion-like particle search experiments

    Energy Technology Data Exchange (ETDEWEB)

    Ahlers, M.; Lindner, A.; Ringwald, A.; Schrempp, L.; Weniger, C.

    2007-10-15

    We point out that chameleon field theories might reveal themselves as an ''afterglow'' effect in axion-like particle search experiments due to chameleon-photon conversion in a magnetic field. We estimate the parameter space which is accessible by currently available technology and find that afterglow experiments could constrain this parameter space in a way complementary to gravitational and Casimir force experiments.In addition, one could reach photon-chameleon couplings which are beyond the sensitivity of common laser polarization experiments. We also sketch the idea of a Fabry-Perot cavity with chameleons which could increase the experimental sensitivity significantly. (orig.)

  11. Status and Prospects of the EDELWEISS-III Direct WIMP Search Experiment

    Science.gov (United States)

    Juillard, A.

    2016-08-01

    EDELWEISS-III is a direct dark matter search experiment, running 800 g heat-and-ionization cryogenic germanium detectors equipped with Full InterDigitized electrodes (FID) for the rejection of near-surface events. We report a preliminary analysis for a subset of the data (35 kg\\cdot days) as well as future prospects for low-mass WIMPs seach.

  12. Liverpool's Discovery: A University Library Applies a New Search Tool to Improve the User Experience

    Science.gov (United States)

    Kenney, Brian

    2011-01-01

    This article features the University of Liverpool's arts and humanities library, which applies a new search tool to improve the user experience. In nearly every way imaginable, the Sydney Jones Library and the Harold Cohen Library--the university's two libraries that serve science, engineering, and medical students--support the lives of their…

  13. Search for Sterile Neutrinos at OPERA and other Long--Baseline Experiments

    CERN Document Server

    Stanco, Luca

    2015-01-01

    The OPERA experiment at the CNGS beam has observed muon to tau neutrino oscillations in the atmospheric sector. Based on this result new limits on the mixing parameters of a massive sterile neutrino may be set. Preliminary results of the analysis done in the 3+1 neutrino framework are here presented. An update of the search for sterile neutrinos in the $\

  14. Feasibility, engineering aspects and physics reach of microwave cavity experiments searching for hidden photons and axions

    CERN Document Server

    Caspers, Friedhelm; Ringwald, A

    2009-01-01

    Using microwave cavities one can build a resonant “light-shining-through-walls” experiment to search for hidden sector photons and axion like particles, predicted in many extensions of the standard model. In this note we make a feasibility study of the sensitivities which can be reached using state of the art technology.

  15. Service validity and service reliability of search, experience and credence services: A scenario study

    NARCIS (Netherlands)

    Galetzka, Mirjam; Verhoeven, Joost W.M.; Pruyn, Ad Th.H.

    2006-01-01

    The purpose of this research is to add to our understanding of the antecedents of customer satisfaction by examining the effects of service reliability (Is the service “correctly” produced?) and service validity (Is the “correct” service produced?) of search, experience and credence services. Design

  16. The Search for Electromagnetic Induction (1820-1831). Experiment No. 20.

    Science.gov (United States)

    Devons, Samuel

    This paper focuses on the search for electromagnetic induction from 1820 to 1831 and the efforts by Augustin Fresnel's colleague, Andre Marie Ampere, in electric and magnetic induction. Faraday's work is discussed with excerpts from his diary on electromagnetism. A variety of different experiments by researchers including Francoise Jean Arago,…

  17. Liverpool's Discovery: A University Library Applies a New Search Tool to Improve the User Experience

    Science.gov (United States)

    Kenney, Brian

    2011-01-01

    This article features the University of Liverpool's arts and humanities library, which applies a new search tool to improve the user experience. In nearly every way imaginable, the Sydney Jones Library and the Harold Cohen Library--the university's two libraries that serve science, engineering, and medical students--support the lives of their…

  18. arXiv Search for Sterile Neutrinos at OPERA and other Long-Baseline Experiments

    CERN Document Server

    Stanco, Luca

    2016-02-23

    The OPERA experiment at the CNGS beam has observed muon to tau neutrino oscillations in the atmospheric sector. Based on this result new limits on the mixing parameters of a massive sterile neutrino may be set. Preliminary results of the analysis done in the 3+1 neutrino framework are here presented. An update of the search for sterile neutrinos in the $\

  19. The Gerda experiment for the search of 0νββ decay in 76Ge

    OpenAIRE

    Ackermann, K. -H.; Agostini, M.; Allardt, M.; Altmann, M; Andreotti, E.; BAKALYAROV A.m.; Balata, M.; Barabanov, I.; Barnabé Heider, M.(Max Planck Institut für Kernphysik, Heidelberg, Germany); Barros, N.; Baudis, L.; Bauer, C; Becerici-Schmidt, N.; Bellotti, E.(Dipartimento di Fisica, Università Milano Bicocca, Milan, Italy); Belogurov, S.

    2013-01-01

    The GERDA collaboration is performing a search for neutrinoless double beta decay of ^{76}Ge with the eponymous detector. The experiment has been installed and commissioned at the Laboratori Nazionali del Gran Sasso and has started operation in November 2011. The design, construction and first operational results are described, along with detailed information from the R&D phase.

  20. Experience in system design for human-robot teaming in urban search & rescue

    NARCIS (Netherlands)

    Kruijff, G.J.M.; Janíček, M.; Keshavdas, S.; Larochelle, B.; Zender, H.; Smets, N.J.J.M.; Mioch, T.; Neerincx, M.A.; Diggelen, J. van; Colas, F.; Liu, M.; Pomerleau, F.; Svoboda, T.; Petriček, T.; Pirri, F.; Giannni, M.; Papadakis, P.; Sinha, A.; Balmer, P.; Tomatis, N.; WOrst, R.; Linder, T.; Surmann, H.; Tretyakov, V.; Corrao, S.; Pratzler-Wanczura, S.; Sulk, M.

    2012-01-01

    The paper describes experience with applying a user-centric design methodology in developing systems for human-robot teaming in Urban Search & Rescue. A human-robot team consists of several robots (rovers/UGVs, microcopter/UAVs), several humans at an off-site command post (mission commander, UGV ope

  1. Feasibility, engineering aspects and physics reach of microwave cavity experiments searching for hidden photons and axions

    Energy Technology Data Exchange (ETDEWEB)

    Caspers, F. [CERN, Geneva (Switzerland); Jaeckel, J. [Univ. of Durham, Inst. for Particle Physics and Phenomenology (United Kingdom); Ringwald, A. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2009-08-15

    Using microwave cavities one can build a resonant ''light-shining-through-walls'' experiment to search for hidden sector photons and axion like particles, predicted in many extensions of the standard model. In this note we make a feasibility study of the sensitivities which can be reached using state of the art technology. (orig.)

  2. Experience in system design for human-robot teaming in urban search & rescue

    NARCIS (Netherlands)

    Kruijff, G.J.M.; Janíček, M.; Keshavdas, S.; Larochelle, B.; Zender, H.; Smets, N.J.J.M.; Mioch, T.; Neerincx, M.A.; Diggelen, J. van; Colas, F.; Liu, M.; Pomerleau, F.; Svoboda, T.; Petriček, T.; Pirri, F.; Giannni, M.; Papadakis, P.; Sinha, A.; Balmer, P.; Tomatis, N.; WOrst, R.; Linder, T.; Surmann, H.; Tretyakov, V.; Corrao, S.; Pratzler-Wanczura, S.; Sulk, M.

    2012-01-01

    The paper describes experience with applying a user-centric design methodology in developing systems for human-robot teaming in Urban Search & Rescue. A human-robot team consists of several robots (rovers/UGVs, microcopter/UAVs), several humans at an off-site command post (mission commander, UGV ope

  3. Experience in system design for human-robot teaming in urban search & rescue

    NARCIS (Netherlands)

    Kruijff, G.J.M.; Janíček, M.; Keshavdas, S.; Larochelle, B.; Zender, H.; Smets, N.J.J.M.; Mioch, T.; Neerincx, M.A.; Diggelen, J. van; Colas, F.; Liu, M.; Pomerleau, F.; Svoboda, T.; Petriček, T.; Pirri, F.; Giannni, M.; Papadakis, P.; Sinha, A.; Balmer, P.; Tomatis, N.; WOrst, R.; Linder, T.; Surmann, H.; Tretyakov, V.; Corrao, S.; Pratzler-Wanczura, S.; Sulk, M.

    2012-01-01

    The paper describes experience with applying a user-centric design methodology in developing systems for human-robot teaming in Urban Search & Rescue. A human-robot team consists of several robots (rovers/UGVs, microcopter/UAVs), several humans at an off-site command post (mission commander, UGV

  4. Beyond standard model Higgs boson searches in the ATLAS and CMS experiments

    CERN Document Server

    Mariotti, Chiara

    2013-01-01

    Searches for a Higgs boson in models beyond the Standard Model at the ATLAS and CMS experiments at the Large Hadron Collider are discussed. No sign of new physics is present in the data collected at 7 and 8 TeV proton center of mass energies. Limits on model parameters are set. Future studies at higher energy are presented.

  5. Searches for supersymmetry in events with one or more leptons using the ATLAS and CMS experiments

    CERN Document Server

    Kirschenmann, Henning

    2016-01-01

    Recent results from searches for supersymmetry in final states with one or more leptons by the ATLAS and CMS collaborations are reported. The data for these results has been recorded in 2015 at $\\sqrt{s}=13$\\,TeV and amounts to an integrated luminosity of 2.2 - 2.3 fb$^{-1}$ for the CMS experiment and 3.2 fb$^{-1}$ for the ATLAS experiment. The results are interpreted in simplified models.

  6. Search for νμ-->νe oscillations in the NOMAD experiment

    Science.gov (United States)

    NOMAD Collaboration; Astier, P.; Autiero, D.; Baldisseri, A.; Baldo-Ceolin, M.; Banner, M.; Bassompierre, G.; Benslama, K.; Besson, N.; Bird, I.; Blumenfeld, B.; Bobisut, F.; Bouchez, J.; Boyd, S.; Bueno, A.; Bunyatov, S.; Camilleri, L.; Cardini, A.; Cattaneo, P. W.; Cavasinni, V.; Cervera-Villanueva, A.; Challis, R.; Chukanov, A.; Collazuol, G.; Conforto, G.; Conta, C.; Contalbrigo, M.; Cousins, R.; Daniels, D.; Degaudenzi, H.; del Prete, T.; de Santo, A.; Dignan, T.; di Lella, L.; Do Couto E Silva, E.; Dumarchez, J.; Ellis, M.; Feldman, G. J.; Ferrari, R.; Ferrère, D.; Flaminio, V.; Fraternali, M.; Gaillard, J.-M.; Gangler, E.; Geiser, A.; Geppert, D.; Gibin, D.; Gninenko, S.; Godley, A.; Gomez-Cadenas, J.-J.; Gosset, J.; Gößling, C.; Gouanère, M.; Grant, A.; Graziani, G.; Guglielmi, A.; Hagner, C.; Hernando, J.; Hubbard, D.; Hurst, P.; Hyett, N.; Iacopini, E.; Joseph, C.; Juget, F.; Kent, N.; Kirsanov, M.; Klimov, O.; Kokkonen, J.; Kovzelev, A.; Krasnoperov, A.; Kustov, D.; Lacaprara, S.; Lachaud, C.; Lakić, B.; Lanza, A.; La Rotonda, L.; Laveder, M.; Letessier-Selvon, A.; Levy, J.-M.; Linssen, L.; Ljubič, A.; Long, J.; Lupi, A.; Marchionni, A.; Martelli, F.; Méchain, X.; Mendiburu, J.-P.; Meyer, J.-P.; Mezzetto, M.; Mishra, S. R.; Moorhead, G. F.; Naumov, D.; Nédélec, P.; Nefedov, Yu.; Nguyen-Mau, C.; Orestano, D.; Pastore, F.; Peak, L. S.; Pennacchio, E.; Pessard, H.; Petti, R.; Placci, A.; Polesello, G.; Pollmann, D.; Polyarush, A.; Popov, B.; Poulsen, C.; Rebuffi, L.; Renò, R.; Rico, J.; Riemann, P.; Roda, C.; Rubbia, A.; Salvatore, F.; Schahmaneche, K.; Schmidt, B.; Schmidt, T.; Sconza, A.; Sevior, M.; Sillou, D.; Soler, F. J. P.; Sozzi, G.; Steele, D.; Stiegler, U.; Stipčević, M.; Stolarczyk, Th.; Tareb-Reyes, M.; Taylor, G. N.; Tereshchenko, V.; Toropin, A.; Touchard, A.-M.; Tovey, S. N.; Tran, M.-T.; Tsesmelis, E.; Ulrichs, J.; Vacavant, L.; Valdata-Nappi, M.; Valuev, V.; Vannucci, F.; Varvell, K. E.; Veltri, M.; Vercesi, V.; Vidal-Sitjes, G.; Vieira, J.-M.; Vinogradova, T.; Weber, F. V.; Weisse, T.; Wilson, F. F.; Winton, L. J.; Yabsley, B. D.; Zaccone, H.; Zuber, K.; Zuccon, P.

    2003-09-01

    We present the results of a search for νμ-->νe oscillations in the NOMAD experiment at CERN. The experiment looked for the appearance of νe in a predominantly νμ wide-band neutrino beam at the CERN SPS. No evidence for oscillations was found. The 90% confidence limits obtained are Δm2~10 eV2.

  7. DEVELOPING AND PROPOSING A CONCEPTUAL MODEL OF THE FLOW EXPERIENCE DURING ONLINE INFORMATION SEARCH

    Directory of Open Access Journals (Sweden)

    Lazoc Alina

    2012-07-01

    Full Text Available Information search is an essential part of the consumer`s decision making process. The online medium offers new opportunities and challenges for information search activities (in and outside the marketing context. We are interested in the way human information experiences and behaviors are affected by this. Very often online games and social web activities are perceived as challenging, engaging and enjoyable, while online information search is far below this evaluation. Our research proposal implies that using the online medium for information search may provoke enjoyable experiences through the flow state, which may in turn positively influence an individual`s exploratory information behavior and encourage his/her pro-active market behavior. The present study sets out to improve the understanding of the online medium`s impact on human`s exploratory behavior. We hypothesize that the inclusion of the online flow experience in our research model will better explain exploratory information search behaviors. A 11-component conceptual framework is proposed to explain the manifestations of flow, its personal and technological determinants and its behavioral consequence in the context of online information search. Our research has the primary purpose to present an integrated online flow model. Its secondary objective is to stimulate extended research in the area of informational behaviors in the digital age. The paper is organized in three sections. In the first section we briefly report the analysis results of the most relevant online flow theory literature and, drawing on it, we are trying to identify variables and relationships among these. In the second part we propose a research model and use prior flow models to specify a range of testable hypothesis. Drawing on the conceptual model developed, the last section of our study presents the final conclusions and proposes further steps in evaluating the model`s validity. Future research directions

  8. Dark matter search in the Milano Double Beta experiment and prospects for the CUORE project

    CERN Document Server

    Guiliani, A; Brofferio, C; Bucci, C; Capelli, S; Cremonesi, O; Fiorini, Ettore; Nucciotti, A; Pavan, M M; Pedretti, M; Pessina, G; Pirro, S; Pobes, C; Previtali, E; Sisti, M; Vanzini, M; Zanotti, L

    2002-01-01

    A Double Beta Decay experiment performed by the Milano group at the Laboratori Nazionali del Gran Sasso (Mi DBD experiment) consists of 20 TeO sub 2 crystals operated as bolometers at T approx = 10mK. An 89-day low-threshold background spectrum, collected with two 340 g bolometers, was selected and analyzed to search for a possible WIMP signal. The exclusion plot in a WIMP mass -- cross section plane was evaluated, assuming WIMP-nucleus spin-independent interaction. WIMP-nucleon cross sections larger than 10 sup - sup 4 pb are excluded between 30 and 100 GeV WIMP masses. The planned expansions of the present experiment, named CUORICINO and CUORE, are presented in terms of sensitivity to WIMP search, considering also the seasonal modulation approach, made possible by the large masses of the future arrays (40 kg for CUORICINO and 760 kg for CUORE).

  9. Beyond Standard Model Searches in the MiniBooNE Experiment

    Directory of Open Access Journals (Sweden)

    Teppei Katori

    2015-01-01

    Full Text Available The MiniBooNE experiment has contributed substantially to beyond standard model searches in the neutrino sector. The experiment was originally designed to test the Δm2~1 eV2 region of the sterile neutrino hypothesis by observing νe(ν-e charged current quasielastic signals from a νμ(ν-μ beam. MiniBooNE observed excesses of νe and ν-e candidate events in neutrino and antineutrino mode, respectively. To date, these excesses have not been explained within the neutrino standard model (νSM; the standard model extended for three massive neutrinos. Confirmation is required by future experiments such as MicroBooNE. MiniBooNE also provided an opportunity for precision studies of Lorentz violation. The results set strict limits for the first time on several parameters of the standard-model extension, the generic formalism for considering Lorentz violation. Most recently, an extension to MiniBooNE running, with a beam tuned in beam-dump mode, is being performed to search for dark sector particles. This review describes these studies, demonstrating that short baseline neutrino experiments are rich environments in new physics searches.

  10. Is It "Writing on Water" or "Strike It Rich?" The Experiences of Prospective Teachers in Using Search Engines

    Science.gov (United States)

    Sahin, Abdurrahman; Cermik, Hulya; Dogan, Birsen

    2010-01-01

    Information searching skills have become increasingly important for prospective teachers with the exponential growth of learning materials on the web. This study is an attempt to understand the experiences of prospective teachers with search engines through metaphoric images and to further investigate whether their experiences are related to the…

  11. Status of the experiment for the search of a dark photon at VEPP–3

    Energy Technology Data Exchange (ETDEWEB)

    Rachek, Igor [Russian Academy of Sciences (RAS), Novosibirsk (Russian Federation). Budker Inst. of Nuclear Physics (BINP); Nikolenko, Dmitri [Russian Academy of Sciences (RAS), Novosibirsk (Russian Federation). Budker Inst. of Nuclear Physics (BINP); Wojtsekhowski, Bogdan B. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2017-04-12

    The status of the experiment to search for a new gauge boson, A', in e+e- annihilation by means of a positron beam incident on a gas hydrogen target internal to the bypass at the VEPP-3 storage ring is reported. The search method is based on a missing mass spectra in reaction e+e- → γA'. It allows observation of the A' signal independently of its decay modes and life time. The projected result of this experiment corresponds to an upper limit on the square of coupling constant ε2 = (0.2 ÷ 1.0) · 10-7 with a signal-to-noise ratio of two to one at A' mass of 5–20 MeV.

  12. New limits on Magnetic Monopoles searches from accelerator and non-accelerator experiments

    CERN Document Server

    Cozzi, M

    2007-01-01

    Here the status of the searches for ``classical Dirac'' Magnetic Monopoles (MMs) at accelerators and for GUT MMs in the cosmic radiation is discussed. We present recent analysis for ``classical Dirac'' monopoles at accelerators and the lowest flux upper limit for Magnetic Monopoles in the mass range 10$^{5}$ - 10$^{12}$ GeV obtained with the SLIM experiment at the Chacaltaya High Altitude Laboratory (5290 m a.s.l.).

  13. Possible optical counterpart of PSR J1357--6429

    CERN Document Server

    Danilenko, A; Mennickent, R E; Pavlov, G; Shibanov, Yu; Zharikov, S; Zyuzin, D

    2012-01-01

    PSR J1357--6429 is a Vela-like radio pulsar that has been recently detected in X-rays and gamma-rays. It powers a compact tail-like X-ray pulsar wind nebula and X-ray-radio plerion associated with an extended TeV source HESS J1356--645. We have performed deep optical observations with the VLT to search for an optical counterpart of the pulsar and its nebula. A point-like source has been detected in V, R, and I bands whose centre position is within the 1-sigma error circle of the X-ray position of the pulsar, and whose colours are distinct from those of ordinary stars. We consider it as a candidate optical counterpart of the pulsar. If it is indeed the counterpart, its 5-sigma offset from the radio pulsar position, measured about 9 yr earlier, implies the transverse velocity of the pulsar in the range of 1600--2000 km s^{-1} at the distance of 2--2.5 kpc, making it the fastest moving pulsar known. The direction of the estimated proper motion coincides with the extension of the pulsar's X-ray tail, suggesting t...

  14. Search for Sterile Neutrinos with the MINOS Long-Baseline Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Timmons, Ashley Michael [Univ. of Manchester (United Kingdom)

    2016-01-01

    This thesis will present a search for sterile neutrinos using data taken with the MINOS experiment between 2005 and 2012. MINOS is a two-detector on-axis experiment based at Fermilab. The NuMI neutrino beam encounters the MINOS Near Detector 1km downstream of the neutrino-production target before traveling a further 734km through the Earth's crust, to reach the Far Detector located at the Soudan Underground Laboratory in Northern Minnesota. By searching for oscillations driven by a large mass splitting, MINOS is sensitive to the existence of sterile neutrinos through looking for any energy-dependent perturbations using a charged-current sample, as well as looking at any relative deficit in neutral current events between the Far and Near Detectors. This thesis will discuss the novel analysis that enabled a search for sterile neutrinos covering five orders of magnitude in the mass splitting and setting a limit in previously unexplored regions of the parameter space $\\left\\{\\Delta m^{2}_{41},\\sin^2\\theta_{24}\\right\\}$, where a 3+1-flavour phenomenological model was used to extract parameter limits. The results presented in this thesis are sensitive to the sterile neutrino parameter space suggested by the LSND and MiniBooNE experiments.

  15. Search for X-rays and relativistic electrons in laboratory discharge experiments

    Science.gov (United States)

    Ostgaard, N.; Carlson, B. E.; Grøndahl, Ø.; Kochkin, P.; Nisi, R.; Gjesteland, T.

    2014-12-01

    In 2013 discharge experiments were carried out at the Technical University of Eindhoven. The experimental set-up was designed to search for both X-rays and electrons produced in meter-scale sparks using a 1 MV Marx generator. In this paper we present the spatial distribution of signals and examine whether they are X-rays only or X-rays and electrons. Other characteristics of the signals will be presented as well. These experiments are carried out in the context of a larger effort to understand the various phenomena of X-rays and gammas from natural lightning.

  16. Latest Results of the OSQAR Photon Regeneration Experiment for Axion-Like Particle Search

    CERN Document Server

    Ballou, Rafik; Duvillaret, Lionel; Finger, Michael; Finger, Miroslav; Flekova, Lucie; Hosek, Jan; Husek, Tomas; Jary, Vladimir; Jost, Remy; Kral, Miroslav; Kunc, Stepan; Macuchova, Karolina; Meissner, Krzysztof A.; Morville, Jérôme; Pugnat, Pierre; Romanini, Daniele; Schott, Matthias; Siemko, Andrzej; Slunecka, Miloslav; Sulc, Miroslav; Vitrant, Guy; Weinsheimer, Christoph; Zicha, Josef

    2014-01-01

    The OSQAR photon regeneration experiment searches for pseudoscalar and scalar axion-like particles by the method of "Light Shining Through a Wall", based on the assumption that these weakly interacting sub-eV particles couple to two photons to give rise to quantum oscillations with optical photons in strong magnetic field. No excess of events has been observed, which constrains the di-photon coupling strength of both pseudoscalar and scalar particles down to $5.7 \\cdot 10^{-8}$ GeV$^{-1}$ in the massless limit. This result is the most stringent constraint on the di-photon coupling strength ever achieved in laboratory experiments.

  17. Neutrinoless double-beta decay search with CUORE and CUORE-0 experiments

    Directory of Open Access Journals (Sweden)

    Moggi N.

    2015-01-01

    Full Text Available The Cryogenic Underground Observatory for Rare Events (CUORE is an upcoming experiment designed to search for the neutrinoless double-beta decays. Observation of the process would unambiguously establish that neutrinos are Majorana particles and provide information on their absolute mass scale hierarchy. CUORE is now under construction and will consist of an array of 988 TeO2 crystal bolometers operated at 10 mK, but the first tower (CUORE-0 is already taking data. The experimental techniques used will be presented as well as the preliminary CUORE-0 results. The current status of the full-mass experiment and its expected sensitivity will then be discussed.

  18. Perspectives for nEDM Search by Crystal Diffraction. Test Experiment and Results

    Energy Technology Data Exchange (ETDEWEB)

    Fedorov, V.V. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg (Russian Federation); Jentschel, M. [Institute Laue-Langevin, Grenoble (France); Kuznetsov, I.A.; Lapin, E.G. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg (Russian Federation); Lelievre-Berna, E.; Nesvizhevsky, V.; Petoukhov, A. [Institute Laue-Langevin, Grenoble (France); Semenikhin, S.Yu. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg (Russian Federation); Soldner, T. [Institute Laue-Langevin, Grenoble (France); Voronin, V.V. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg (Russian Federation)], E-mail: vvv@pnpi.spb.ru; Braginetz, Yu.P. [Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg (Russian Federation)

    2009-08-15

    An experiment searching for the neutron electric dipole moment by measuring spin-rotations in a non-centrosymmetric crystal was carried out to investigate the statistical sensitivity and systematic effects of the method. The preliminary result of this experiment is d{sub n}=(2.5{+-}6.5).10{sup -24} e.cm. The performance was essentially limited by the low luminosity of the prototype setup. With a dedicated setup and a large quartz crystal, the expected accuracy is {approx}2.10{sup -26} e.cm for 100 days of data collection.

  19. New Physics search in mono-jet final states with the ATLAS experiment at the LHC

    CERN Document Server

    Gustavino, Giuliano; The ATLAS collaboration

    2015-01-01

    The search for New Physics in final states with an energetic jet and large missing transverse momentum plays a major role in the physics program of the LHC experiments. This experimental signature is sensitive to different New Physics models including different scenarios of supersymmetry, models that predict the existence of extra dimensions and the production of Weakly Interacting Dark Matter candidates. Results based on the LHC Run-1 dataset corrisponding to 20.3 fb$^{-1}$ and firsts performance plots based on the data collected at the center of mass energy of 13 TeV with the ATLAS experiment at the LHC are presented.

  20. The MTV experiment: searching for T-violation in polarized Li-8 at TRIUMF

    Energy Technology Data Exchange (ETDEWEB)

    Murata, J., E-mail: jiro@rikkyo.ac.jp [Rikkyo University, Department of Physics (Japan); Baba, H. [RIKEN, Nishina Center (Japan); Behr, J. A. [TRIUMF (Canada); Goto, F. [Nagoya University, Department of Physics (Japan); Inaba, S. [Rikkyo University, Department of Physics (Japan); Kawamura, H. [Tohoku University, Cyclotron and Radioisotope Center (Japan); Kitaguchi, M. [Nagoya University, Department of Physics (Japan); Levy, C. D. P. [TRIUMF (Canada); Masuda, H.; Nakaya, Y.; Ninomiya, K.; Onishi, J. [Rikkyo University, Department of Physics (Japan); Openshaw, R.; Pearson, M. [TRIUMF (Canada); Sakamoto, Y. [Rikkyo University, Department of Physics (Japan); Shimizu, H. [Nagoya University, Department of Physics (Japan); Shimizu, Y.; Tanaka, S.; Tanaka, Y.; Tanuma, R. [Rikkyo University, Department of Physics (Japan); and others

    2016-12-15

    The MTV experiment (Mott Polarimetry for T-Violation Experiment) is running at TRIUMF, to search for a large T-violating transverse electron-polarization in polarized {sup 8}Li β-decay. We aim at reaching precision of 10{sup −4} for the R-correlation, which is defined as a T-violating triple vector correlation in the β-decay rate function. A Mott polarimeter system using a CDC (Cylindrical Drift Chamber) is used to measure the left-right scattering asymmetry in the Mott scattering from a thin metal foil. In the present study, we aim to discuss systematic effects in Mott polarimetry using the CDC.

  1. Search for K+ → π+νν¯ at the NA62 experiment

    Science.gov (United States)

    Duk, Viacheslav

    2016-11-01

    Looking for phenomena beyond the Standard Model (SM) in rare decays is a complementary approach to direct searches for New Physics (NP) at colliders. One of the theoretically cleanest processes is the ultra rare decay K+ → π+νν¯. The goal of the NA62 experiment at CERN SPS is to measure the branching ratio (BR) of this decay with 10% precision. The experiment has been launched in 2014. In 2015, the detector was commissioned at a low intensity beam. The experimental setup is described and performances achieved in 2015 are discussed in view of the final measurement.

  2. ELABORATING A MEASUREMENT INSTRUMENT FOR THE FLOW EXPERIENCE DURING ONLINE INFORMATION SEARCH

    Directory of Open Access Journals (Sweden)

    Caraivan Luiza

    2012-12-01

    Full Text Available Flow is a construct imported in marketing research from social sciences in order to examine consumer behavior in the online medium. The construct describes a state of deep involvement in a challenging activity, most frequently characterized by high levels of enjoyment, control and concentration. Researchers found that the degree to which online experience is challenging can be defined, measured, and related well to important marketing variables. As shown by our extensive literature review, flow measurements include antecedents, dimensions and consequences of flow. The present paper represents a detailed description of the construct`s operationalization in the context of online information search. In this respect, our main goal is to produce a basic instrument to evaluate the flow experience of online search, in order to capitalize on the premises of an interactive, complex informational medium – the World Wide Web – and on the consequence of an exploratory informational behavior of users. The instrument is conceived to offer a primal possibility to collect data. The composition, source and significance of the 11 scales used to measure the multiple factors of the flow experience during online search are detailed in this study with the aim to ensure the compliance with scientific rigors and to facilitate correct reports of data related to the reliability and validity of measurements. For further research, we propose factor analysis to test the resulted instrument and to ensure that the measures employed are psychometrically sound. Factor analysis refers to a wide range of statistic techniques used to represent a set of variables in concordance with a reduced number of hypothetical variables called factors. Factorial analysis is used to solve two types of problems: reducing the number of variables to increase data processing speed and identifying hidden patterns in the existent data relations. However, we expect our scales to perform

  3. Searches for the Violation of Pauli Exclusion Principle at LNGS in VIP(-2) experiment

    CERN Document Server

    Shi, H; Bertolucci, S; Berucci, C; Bragadireanu, A M; Cargnelli, M; Clozza, A; Curceanu, C; De Paolis, L; Di Matteo, S; d'Uffizi, A; Egger, J P; Guaraldo, C; Iliescu, M; Ishiwatari, T; Marton, J; Laubenstein, M; Milotti, E; Pietreanu, D; Piscicchia, K; Ponta, T; Vidal, A.Romero; Sbardella, E; Scordo, A; Sirghi, D L; Sirghi, F; Sperandio, L; Vazquez Doce, O; Widmann, E; Zmeskal, J

    2016-01-01

    The VIP (Violation of Pauli exclusion principle) experiment and its follow-up experiment VIP-2 at the Laboratori Nazionali del Gran Sasso (LNGS) search for X-rays from Cu atomic states that are prohibited by the Pauli Exclusion Principle (PEP). The candidate events, if they exist, will originate from the transition of a $2p$ orbit electron to the ground state which is already occupied by two electrons. The present limit on the probability for PEP violation for electron is 4.7 $\\times10^{-29}$ set by the VIP experiment. With upgraded detectors for high precision X-ray spectroscopy, the VIP-2 experiment will improve the sensitivity by two orders of magnitude.

  4. Search for heavy fermions with the ATLAS experiment at the LHC collider

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00359999; Santiago, José; Onofre, António

    In the present thesis a search for new heavy fermions using LHC data collected in 2012 by the ATLAS experiment is presented. In particular, a search for pair and single production of vector-like quarks with electric charge 2/3 ($T$) and -1/3 ($B$) decaying to a $Z$ boson is discussed. For this search the analysis was divided in two channels, depending on the lepton multiplicity, and both channels were combined at the end for the final results. Since no evidence for signal was found, limits on the mass of the vector-like quarks were evaluated. The observed (expected) limit on the mass of an $SU(2)$ singlet $T$ quark is 655~GeV (625~GeV), while the observed (expected) limit on the mass of a $T$ quark in a $(T,B)$ doublet is 735~GeV (720~GeV). The observed (expected) limit on the mass of an $SU(2)$ singlet $B$ quark is 685~GeV (670~GeV), while the observed (expected) limit on the mass of a $B$ quark in a $(B,Y)$ doublet is 755~GeV (755~GeV). The impact of a heavy gluon in the searches for pair production of vect...

  5. submitter Search for Pair-Produced Supersymmetric Top Quark Partners with the ATLAS Experiment

    CERN Document Server

    Abulaiti, Yiming; Jon-And, Kerstin

    Searches for the supersymmetric partner of the top quark (stop) are motivated by natural supersymmetry, where the stop has to be light to cancel the large radiative corrections to the Higgs boson mass. This thesis presents three different searches for the stop at √s = 8 TeV and √s = 13 TeV using data from the ATLAS experiment at CERN’s Large Hadron Collider. The thesis also includes a study of the primary vertex reconstruction performance in data and simulation at √s = 7 TeV using tt and Z events. All stop searches presented are carried out in final states with a single lepton, four or more jets and large missing transverse energy. A search for direct stop pair production is conducted with 20.3 fb−1 of data at a center-of-mass energy of √s = 8 TeV. Several stop decay scenarios are considered, including those to a top quark and the lightest neutralino and to a bottom quark and the lightest chargino. The sensitivity of the analysis is also studied in the context of various phenomenological MSSM mode...

  6. First Results from the Cryogenic Dark Matter Search Experiment at the Deep Site

    Energy Technology Data Exchange (ETDEWEB)

    Mandic, Vuk [Univ. of California, Berkeley, CA (United States)

    2004-06-01

    The Cryogenic Dark Matter Search (CDMS) experiment is designed to search for dark matter in the form of the Weakly Interacting Massive Particles (WIMPs). For this purpose, CDMS uses detectors based on crystals of Ge and Si, operated at the temperature of 20 mK, and providing a two-fold signature of an interaction: the ionization and the athermal phonon signals. The two signals, along with the passive and active shielding of the experimental setup, and with the underground experimental sites, allow very effective suppression and rejection of different types of backgrounds. This dissertation presents the commissioning and the results of the first WIMP-search run performed by the CDMS collaboration at the deep underground site at the Soudan mine in Minnesota. We develop different methods of suppressing the dominant background due to the electron-recoil events taking place at the detector surface and we apply these algorithms to the data set. These results place the world's most sensitive limits on the WIMP-nucleon spin-independent elastic-scattering cross-section. Finally, they examine the compatibility of the supersymmetric WIMP-models with the direct-detection experiments (such as CDMS) and discuss the implications of the new CDMS result on these models.

  7. A search for muon neutrino to electron neutrino oscillations in the MINOS Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Ochoa Ricoux, Juan Pedro [California Inst. of Technology (CalTech), Pasadena, CA (United States)

    2009-01-01

    We perform a search for vμ → ve oscillations, a process which would manifest a nonzero value of the θ13 mixing angle, in the MINOS long-baseline neutrino oscillation experiment. The analysis consists of searching for an excess of ve charged-current candidate events over the predicted backgrounds, made mostly of neutral-current events with high electromagnetic content. A novel technique to select electron neutrino events is developed, which achieves an improved separation between the signal and the backgrounds, and which consequently yields a better reach in θ13. The backgrounds are predicted in the Far Detector from Near Detector measurements. An excess is observed in the Far Detector data over the predicted backgrounds, which is consistent with the background-only hypothesis at 1.2 standard deviations.

  8. Development of a super-resolution optical microscope for directional dark matter search experiment

    Energy Technology Data Exchange (ETDEWEB)

    Alexandrov, A., E-mail: andrey.alexandrov@na.infn.it [INFN - Napoli, I-80125 Napoli (Italy); LPI - Lebedev Physical Institute of the Russian Academy of Sciences, RUS-119991 Moscow (Russian Federation); Asada, T. [Nagoya University, J-464-8602 Nagoya (Japan); Consiglio, L.; D' Ambrosio, N. [INFN - Laboratori Nazionali del Gran Sasso, I-67010 Assergi (AQ) (Italy); De Lellis, G. [INFN - Napoli, I-80125 Napoli (Italy); University of Naples, I-80125 Napoli (Italy); Di Crescenzo, A. [INFN - Napoli, I-80125 Napoli (Italy); Di Marco, N. [INFN - Laboratori Nazionali del Gran Sasso, I-67010 Assergi (AQ) (Italy); Furuya, S.; Hakamata, K.; Ishikawa, M.; Katsuragawa, T.; Kuwabara, K.; Machii, S.; Naka, T. [Nagoya University, J-464-8602 Nagoya (Japan); Pupilli, F. [INFN - Laboratori Nazionali di Frascati, I-00044 Frascati (RM) (Italy); Sirignano, C. [University of Padova and INFN, Padova (PD), 35131 Italy (Italy); Tawara, Y. [Nagoya University, J-464-8602 Nagoya (Japan); Tioukov, V. [INFN - Napoli, I-80125 Napoli (Italy); Umemoto, A.; Yoshimoto, M. [Nagoya University, J-464-8602 Nagoya (Japan)

    2016-07-11

    Nuclear emulsion is a perfect choice for a detector for directional DM search because of its high density and excellent position accuracy. The minimal detectable track length of a recoil nucleus in emulsion is required to be at least 100 nm, making the resolution of conventional optical microscopes insufficient to resolve them. Here we report about the R&D on a super-resolution optical microscope to be used in future directional DM search experiments with nuclear emulsion as a detector media. The microscope will be fully automatic, will use novel image acquisition and analysis techniques, will achieve the spatial resolution of the order of few tens of nm and will be capable of reconstructing recoil tracks with the length of at least 100 nm with high angular resolution.

  9. Improved Search for a Light Sterile Neutrino with the Full Configuration of the Daya Bay Experiment

    Science.gov (United States)

    An, F. P.; Balantekin, A. B.; Band, H. R.; Bishai, M.; Blyth, S.; Cao, D.; Cao, G. F.; Cao, J.; Cen, W. R.; Chan, Y. L.; Chang, J. F.; Chang, L. C.; Chang, Y.; Chen, H. S.; Chen, Q. Y.; Chen, S. M.; Chen, Y. X.; Chen, Y.; Cheng, J.-H.; Cheng, J.; Cheng, Y. P.; Cheng, Z. K.; Cherwinka, J. J.; Chu, M. C.; Chukanov, A.; Cummings, J. P.; de Arcos, J.; Deng, Z. Y.; Ding, X. F.; Ding, Y. Y.; Diwan, M. V.; Dolgareva, M.; Dove, J.; Dwyer, D. A.; Edwards, W. R.; Gill, R.; Gonchar, M.; Gong, G. H.; Gong, H.; Grassi, M.; Gu, W. Q.; Guan, M. Y.; Guo, L.; Guo, R. P.; Guo, X. H.; Guo, Z.; Hackenburg, R. W.; Han, R.; Hans, S.; He, M.; Heeger, K. M.; Heng, Y. K.; Higuera, A.; Hor, Y. K.; Hsiung, Y. B.; Hu, B. Z.; Hu, T.; Hu, W.; Huang, E. C.; Huang, H. X.; Huang, X. T.; Huber, P.; Huo, W.; Hussain, G.; Jaffe, D. E.; Jaffke, P.; Jen, K. L.; Jetter, S.; Ji, X. P.; Ji, X. L.; Jiao, J. B.; Johnson, R. A.; Joshi, J.; Kang, L.; Kettell, S. H.; Kohn, S.; Kramer, M.; Kwan, K. K.; Kwok, M. W.; Kwok, T.; Langford, T. J.; Lau, K.; Lebanowski, L.; Lee, J.; Lee, J. H. C.; Lei, R. T.; Leitner, R.; Leung, J. K. C.; Li, C.; Li, D. J.; Li, F.; Li, G. S.; Li, Q. J.; Li, S.; Li, S. C.; Li, W. D.; Li, X. N.; Li, Y. F.; Li, Z. B.; Liang, H.; Lin, C. J.; Lin, G. L.; Lin, S.; Lin, S. K.; Lin, Y.-C.; Ling, J. J.; Link, J. M.; Littenberg, L.; Littlejohn, B. R.; Liu, D. W.; Liu, J. L.; Liu, J. C.; Loh, C. W.; Lu, C.; Lu, H. Q.; Lu, J. S.; Luk, K. B.; Lv, Z.; Ma, Q. M.; Ma, X. Y.; Ma, X. B.; Ma, Y. Q.; Malyshkin, Y.; Martinez Caicedo, D. A.; McDonald, K. T.; McKeown, R. D.; Mitchell, I.; Mooney, M.; Nakajima, Y.; Napolitano, J.; Naumov, D.; Naumova, E.; Ngai, H. Y.; Ning, Z.; Ochoa-Ricoux, J. P.; Olshevskiy, A.; Pan, H.-R.; Park, J.; Patton, S.; Pec, V.; Peng, J. C.; Pinsky, L.; Pun, C. S. J.; Qi, F. Z.; Qi, M.; Qian, X.; Raper, N.; Ren, J.; Rosero, R.; Roskovec, B.; Ruan, X. C.; Steiner, H.; Sun, G. X.; Sun, J. L.; Tang, W.; Taychenachev, D.; Treskov, K.; Tsang, K. V.; Tull, C. E.; Viaux, N.; Viren, B.; Vorobel, V.; Wang, C. H.; Wang, M.; Wang, N. Y.; Wang, R. G.; Wang, W.; Wang, X.; Wang, Y. F.; Wang, Z.; Wang, Z.; Wang, Z. M.; Wei, H. Y.; Wen, L. J.; Whisnant, K.; White, C. G.; Whitehead, L.; Wise, T.; Wong, H. L. H.; Wong, S. C. F.; Worcester, E.; Wu, C.-H.; Wu, Q.; Wu, W. J.; Xia, D. M.; Xia, J. K.; Xing, Z. Z.; Xu, J. Y.; Xu, J. L.; Xu, Y.; Xue, T.; Yang, C. G.; Yang, H.; Yang, L.; Yang, M. S.; Yang, M. T.; Ye, M.; Ye, Z.; Yeh, M.; Young, B. L.; Yu, Z. Y.; Zeng, S.; Zhan, L.; Zhang, C.; Zhang, H. H.; Zhang, J. W.; Zhang, Q. M.; Zhang, X. T.; Zhang, Y. M.; Zhang, Y. X.; Zhang, Y. M.; Zhang, Z. J.; Zhang, Z. Y.; Zhang, Z. P.; Zhao, J.; Zhao, Q. W.; Zhao, Y. B.; Zhong, W. L.; Zhou, L.; Zhou, N.; Zhuang, H. L.; Zou, J. H.; Daya Bay Collaboration

    2016-10-01

    This Letter reports an improved search for light sterile neutrino mixing in the electron antineutrino disappearance channel with the full configuration of the Daya Bay Reactor Neutrino Experiment. With an additional 404 days of data collected in eight antineutrino detectors, this search benefits from 3.6 times the statistics available to the previous publication, as well as from improvements in energy calibration and background reduction. A relative comparison of the rate and energy spectrum of reactor antineutrinos in the three experimental halls yields no evidence of sterile neutrino mixing in the 2 ×10-4≲|Δ m412|≲0.3 eV2 mass range. The resulting limits on sin22 θ14 are improved by approx imately a factor of 2 over previous results and constitute the most stringent constraints to date in the |Δ m412|≲0.2 eV2 region.

  10. Low-mass dark matter search results from full exposure of PandaX-I experiment

    CERN Document Server

    Xiao, Xiang; Tan, Andy; Chen, Yunhua; Cui, Xiangyi; Fang, Deqing; Fu, Changbo; Giboni, Karl L; Gong, Haowei; Guo, Guodong; He, Ming; Ji, Xiangdong; Ju, Yonglin; Lei, Siao; Li, Shaoli; Lin, Qing; Liu, Huaxuan; Liu, Jianglai; Liu, Xiang; Lorenzon, Wolfgang; Ma, Yugang; Mao, Yajun; Ni, Kaixuan; Pushkin, Kirill; Ren, Xiangxiang; Schubnell, Michael; Shen, Manbing; Shi, Yuji; Stephenson, Scott; Wang, Hongwei; Wang, Jiming; Wang, Meng; Wang, Siguang; Wang, Xuming; Wang, Zhou; Wu, Shiyong; Xiao, Mengjiao; Xie, Pengwei; Yan, Binbin; You, Yinghui; Zeng, Xionghui; Zhang, Tao; Zhao, Li; Zhou, Xiaopeng; Zhu, Zhonghua

    2015-01-01

    We report the results of a weakly-interacting massive particle (WIMP) dark matter search using the full 80.1\\;live-day exposure of the first stage of the PandaX experiment (PandaX-I) located in the China Jin-Ping Underground Laboratory. The PandaX-I detector has been optimized for detecting low-mass WIMPs, achieving a photon detection efficiency of 9.6\\%. With a fiducial liquid xenon target mass of 54.0\\,kg, no significant excess event were found above the expected background. A profile likelihood analysis confirms our earlier finding that the PandaX-I data disfavor all positive low-mass WIMP signals reported in the literature under standard assumptions. A stringent bound on the low mass WIMP is set at WIMP mass below 10\\,GeV/c$^2$, demonstrating that liquid xenon detectors can be competitive for low-mass WIMP searches.

  11. Improved Search for a Light Sterile Neutrino with the Full Configuration of the Daya Bay Experiment

    CERN Document Server

    An, F P; Band, H R; Bishai, M; Blyth, S; Cao, D; Cao, G F; Cao, J; Cen, W R; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chen, H S; Chen, Q Y; Chen, S M; Chen, Y X; Chen, Y; Cheng, J -H; Cheng, J; Cheng, Y P; Cheng, Z K; Cherwinka, J J; Chu, M C; Chukanov, A; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, X F; Ding, Y Y; Diwan, M V; Dolgareva, M; Dove, J; Dwyer, D A; Edwards, W R; Gill, R; Gonchar, M; Gong, G H; Gong, H; Grassi, M; Gu, W Q; Guan, M Y; Guo, L; Guo, R P; Guo, X H; Guo, Z; Hackenburg, R W; Han, R; Hans, S; He, M; Heeger, K M; Heng, Y K; Higuera, A; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, T; Hu, W; Huang, E C; Huang, H X; Huang, X T; Huber, P; Huo, W; Hussain, G; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiao, J B; Johnson, R A; Joshi, J; Kang, L; Kettell, S H; Kohn, S; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Langford, T J; Lau, K; Lebanowski, L; Lee, J; Lee, J H C; Lei, R T; Leitner, R; Leung, J K C; Li, C; Li, D J; Li, F; Li, G S; Li, Q J; Li, S; Li, S C; Li, W D; Li, X N; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, S; Lin, S K; Lin, Y -C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, J L; Liu, J C; Loh, C W; Lu, C; Lu, H Q; Lu, J S; Luk, K B; Lv, Z; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; Malyshkin, Y; Caicedo, D A Martinez; McDonald, K T; McKeown, R D; Mitchell, I; Mooney, M; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevskiy, A; Pan, H -R; Park, J; Patton, S; Pec, V; Peng, J C; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Steiner, H; Sun, G X; Sun, J L; Tang, W; Taychenachev, D; Treskov, K; Tsang, K V; Tull, C E; Viaux, N; Viren, B; Vorobel, V; Wang, C H; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, X; Wang, Y F; Wang, Z; Wang, Z; Wang, Z M; Wei, H Y; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, C -H; Wu, Q; Wu, W J; Xia, D M; Xia, J K; Xing, Z Z; Xu, J Y; Xu, J L; Xu, Y; Xue, T; Yang, C G; Yang, H; Yang, L; Yang, M S; Yang, M T; Ye, M; Ye, Z; Yeh, M; Young, B L; Yu, Z Y; Zeng, S; Zhan, L; Zhang, C; Zhang, H H; Zhang, J W; Zhang, Q M; Zhang, X T; Zhang, Y M; Zhang, Y X; Zhang, Y M; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y B; Zhong, W L; Zhou, L; Zhou, N; Zhuang, H L; Zou, J H

    2016-01-01

    This Letter reports an improved search for light sterile neutrino mixing in the electron antineutrino disappearance channel with the full configuration of the Daya Bay Reactor Neutrino Experiment. With an additional 404 days of data collected in eight antineutrino detectors, this search benefits from 3.6 times the statistics available to the previous publication, as well as from improvements in energy calibration and background reduction. A relative comparison of the rate and energy spectrum of reactor antineutrinos in the three experimental halls yields no evidence of sterile neutrino mixing in the $2\\times10^{-4}$~eV$^{2} \\lesssim |\\Delta m^{2}_{41}| \\lesssim 0.3$~eV$^{2}$ mass range. The resulting limits on $\\sin^{2}2\\theta_{14}$ are improved by approximately a factor of two over previous results and constitute the most stringent constraints to date in the $|\\Delta m^{2}_{41}| \\lesssim 0.2$ eV$^{2}$ region.

  12. Tree and Hashing Data Structures to Speed up Chemical Searches: Analysis and Experiments.

    Science.gov (United States)

    Nasr, Ramzi; Kristensen, Thomas; Baldi, Pierre

    2011-09-01

    In many large chemoinformatics database systems, molecules are represented by long binary fingerprint vectors whose components record the presence or absence of particular functional groups or combinatorial features. For a given query molecule, one is interested in retrieving all the molecules in the database with a similarity to the query above a certain threshold. Here we describe a method for speeding up chemical searches in these large databases of small molecules by combining previously developed tree and hashing data structures to prune the search space without any false negatives. More importantly, we provide a mathematical analysis that allows one to predict the level of pruning, and validate the quality of the predictions of the method through simulation experiments.

  13. A Comparison of Article Search APIs via Blinded Experiment and Developer Review

    Directory of Open Access Journals (Sweden)

    Jonathan Rochkind

    2013-01-01

    Full Text Available This study looks at perceived user preference between products that can provide a scholarly article search service via an application programming interface (API. The study set up a blinded review and asked users at Johns Hopkins to select the service that provided the most useful results. Few statistically significant preferences were detected, and some interpretation is provided of what the results might tell us. The specific products evaluated for this study are: Serials Solutions Summon, Ex Libris Primo, EBSCO EDS, EBSCOHost ‘traditional’ API, and Elsevier Scopus. Re-usable open source tools for implementing article search were created to support the study and future development, and a developer review of the APIs is included based on the developer's experience in this implementation.

  14. a Next-Generation Cavity Microwave Experiment to Search for Dark-Matter Axions

    Science.gov (United States)

    Bibber, K. Van; Stöffl, W.; Anthony, P. L.; Sikivie, P.; Sullivan, N. S.; Tanner, D. B.; Železný, V.; Golubev, N. A.; Kazachenko, O. V.; Kravchuk, L. V.; Kuzmin, V.; Romanov, G. V.; Sekachev, I. V.; Rosenberg, L. J.; Hagmann, C.; Moltz, D. M.; Nezrick, F.; Turner, M. S.; Villa, F.

    We propose a large-scale experimental search for dark-matter axions which may constitute an important fraction of our own galactic halo. As shown by Sikivie,1 dark-matter axions may be detected by their stimulated conversion into monochromatic microwave photons in a tunable high-Q cavity inside a strong magnetic field. The principal improvement in power sensitivity over two earlier pilot experiments (×25) derives from the large-volume high field superconducting magnet (the NASA SUMMA coils). The improvement in mass range (1.5 to 12.6 μeV) will result from the use of several microwave cavity arrays, of 2n cavities each, over the course of the experimental program, rather than a single cavity. We are participating in a joint venture with the Institute for Nuclear Research of the Russian Academy of Sciences to do R&D on metalized precision-formed ceramic microwave cavities for the axion search.

  15. Search for rare B meson decays at the BaBar experiment

    CERN Document Server

    Cheaib, Racha

    2016-01-01

    b to s transitions are flavour-changing neutral current (FCNC) processes that play an important role in the search for physics beyond the Standard Model (SM). Contributions from virtual particles in the loop are predicted to deviate observables, such as the branching fraction, from their SM expectations. Using data from the BaBar experiment, we present the first search for the rare decay B to K tau tau. The BABAR results on the measurement of the angular asymmetries of B to Kstar l l, where l is an electron or muon, are also reported. In addition, using a time-dependent analysis of B to KS0 pi pi gamma, the mixing induced CP-asymmetry for the radiative FCNC decay, B to KS0 rho gamma, is measured, along with an amplitude analysis of the m (K pi) and m (K pi pi) spectrum.

  16. The Cryogenic Dark Matter Search (CDMS-II) Experiment: First Results from the Soudan Mine

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Clarence Leeder [Stanford Univ., CA (United States)

    2004-09-01

    There is an abundance of evidence that the majority of the mass of the universe is in the form of non-baryonic non-luminous matter that was non-relativistic at the time when matter began to dominate the energy density. Weakly Interacting Massive Particles, or WIMPs, are attractive cold dark matter candidates because they would have a relic abundance today of ~0.1 which is consistent with precision cosmological measurements. WIMPs are also well motivated theoretically. Many minimal supersymmetric extensions of the Standard Model have WIMPs in the form of the lightest supersymmetric partner, typically taken to be the neutralino. The CDMS II experiment searches for WIMPs via their elastic scattering off of nuclei. The experiment uses Ge and Si ZIP detectors, operated at <50 mK, which simultaneously measure the ionization and athermal phonons produced by the scattering of an external particle. The dominant background for the experiment comes from electromagnetic interactions taking place very close to the detector surface. Analysis of the phonon signal from these interactions makes it possible to discriminate them from interactions caused by WIMPs. This thesis presents the details of an important aspect of the phonon pulse shape analysis known as the ''Lookup Table Correction''. The Lookup Table Correction is a position dependent calibration of the ZIP phonon response which improves the rejection of events scattering near the detector surface. The CDMS collaboration has recently commissioned its experimental installation at the Soudan Mine. This thesis presents an analysis of the data from the first WIMP search at the Soudan Mine. The results of this analysis set the world's lowest exclusion limit making the CDMS II experiment at Soudan the most sensitive WIMP search to this date.

  17. Results and prospects of axion searches with the OSQAR and ALPS II experiment

    Energy Technology Data Exchange (ETDEWEB)

    Schott, Matthias; Weinsheimer, Christoph [Johannes Gutenberg-Universitaet, Mainz (Germany)

    2015-07-01

    The Axion and axion-like particles (ALPs) are well motivated hypothetical Spin-0 bosons, naturally arising in many extensions of the Standard Model. At first introduced to solve the strong-CP problem by breaking an additional U(1) Pecci-Quinn symmetry, meanwhile several astrophysical observations hint to the ALPs sector as well. In so called Light-Shining-through-Wall (LSW) experiments the effective diphoton vertex inherent to Axions and ALPs is exploited for direct searches. High power laser beams traversing strong magnetic fields are used to create and annihilate ALPs making them accessible in laboratory setups. In this talk the latest results of the of the OSQAR experiment (CERN) are presented as well as prospects of near future enhancements by the ALPS II (DESY) experiment aiming for an improved sensitivity of 3 orders of magnitude.

  18. Status of the GERDA experiment aimed to search for neutrinoless double beta decay of 76Ge

    CERN Document Server

    Smolnikov, Anatoly A

    2008-01-01

    The progress in the development of the new international Gerda (GErmanium Detector Array) experiment is presented. Main purpose of the experiment is to search for the neutrinoless double beta decay of 76Ge. The experimental set up is under construction in the underground laboratory of LNGS. Gerda will operate with bare germanium semiconductor detectors (enriched in 76Ge) situated in liquid argon. In the Phase I the existing enriched detectors from the previous Heidelberg-Moscow and IGEX experiments are employed, in the Phase II the new segmented detectors made from recently produced enriched material will be added. Novel concepts for background suppression including detector segmentation and anti-coincidence with LAr scintillation are developed.

  19. A Search for nu_mu to nu_e oscillations in the NOMAD experiment

    CERN Document Server

    Godley, Andrew R

    2000-01-01

    The NOMAD experiment is a neutrino oscillation experiment. capable of identifying Vμ, -Vμ, Ve, -Ve and Vt for use in oscillation analyses. A search for Vμ --> Ve oscillations is conducted, emphasising the development of two separate beam simulators, to provide the background, (no oscillation), lie signal. Both beam descriptions include fits to the results of the SPY experiment that measured hadron production from a 450 GeV proton beam on beryllium target. An independent analysis of the raw SPY data to produce the particle yield is reported. A series of criteria are described for the selection and classification of neutrino events. These produce the data samples necessary for both tuning the beam simulation and determining the oscillation signal. The development of a GEANT and FLUKA based Monte Carlo beam simulator is presented; providing good agreement to the measured neutrino beam. This simulation method has sizeable variations depending on the beamline geometry, which is not knonm precisely. This causes ...

  20. The ontology supported intelligent system for experiment search in the scientific Research center

    Directory of Open Access Journals (Sweden)

    Cvjetković Vladimir

    2014-01-01

    Full Text Available Ontologies and corresponding knowledge bases can be quite successfully used for many tasks that rely on domain knowledge and semantic structures, which should be available for machine processing and sharing. Using SPARQL queries for retrieval of required elements from ontologies and knowledge bases, can significantly simplify modeling of arbitrary structures of concepts and data, and implementation of required functionalities. This paper describes developed ontology for support of Research Centre for testing of active substances that conducts scientific experiments. According to created ontology corresponding knowledge base was made and populated with real experimental data. Developed ontology and knowledge base are directly used for an intelligent system of experiment search which is based on many criteria from ontology. Proposed system gets the desired search result, which is actually an experiment in the form of a written report. Presented solution and implementation are very flexible and adaptable, and can be used as kind of a template by similar information system dealing with biological or similar complex system.

  1. Electromagnetic Counterparts to Black Hole Mergers

    Science.gov (United States)

    Schnittman, Jeremy D.

    2011-01-01

    During the final moments of a binary black hole (BH) merger, the gravitational wave (GW) luminosity of the system is greater than the combined electromagnetic (EM) output of the entire observable universe. However, the extremely weak coupling between GWs and ordinary matter makes these waves very difficult to detect directly. Fortunately, the inspirating BH system will interact strongly-on a purely Newtonian level-with any surrounding material in the host galaxy, and this matter can in turn produce unique EM signals detectable at Earth. By identifying EM counterparts to GW sources, we will be able to study the host environments of the merging BHs, in turn greatly expanding the scientific yield of a mission like LISA. Here we present a comprehensive review of the recent literature on the subject of EM counterparts, as well as a discussion of the theoretical and observational advances required to fully realize the scientific potential of the field.

  2. Inclusive Searches for Squarks and Gluinos with the ATLAS Experiment at LHC

    CERN Document Server

    Maurer, Julien; The ATLAS collaboration

    2015-01-01

    The ATLAS experiment at LHC has conducted searches for the supersymmetric partners of quarks and gluons in the proton-proton collision data collected in 2012, at a centre-of-mass energy of 8 TeV and with an integrated luminosity of 20.3 fb$^{-1}$, using various topologies corresponding to different decay modes. No significant excess above SM predictions was observed, and exclusion limits were set on the squarks and gluinos masses in various scenarios. For light neutralinos, the experimental sensitivity reached gluino masses up to 1.3 TeV, and squark masses up to 850 GeV.

  3. Experiment to search for ultra high energy. gamma. -ray sources from the South Pole

    Energy Technology Data Exchange (ETDEWEB)

    Smith, N.J.T.; Perrett, J.C.; Pomerantz, M.A.; Hillas, A.M.; Ogden, P.A.; Patel, M.; Reid, R.J.O.; Watson, A.A.

    1989-04-01

    We describe the construction and performance characteristics of an extensive air shower array which has been established at the geographic South Pole. The experiment has been designed to search for sources for cosmic rays with primary energies above 50 TeV with an angular resolution of about 1/sup 0/. The array has an enclosed area of 6235 m/sup 2/ and is at an altitude of 2835 m (695 g cm/sup -2/). The unique advantage of the site is the circumpolar nature of all candidate sources, including SN1987A, which lie at a constant zenith angle.

  4. Search for the decay phi -> K0 K0bar gamma with the KLOE experiment

    CERN Document Server

    Ambrosino, F; Antonelli, M; Archilli, F; Beltrame, P; Bencivenni, G; Bertolucci, S; Bini, C; Bloise, C; Bocchetta, S; Bossi, F; Branchini, P; Capon, G; Capussela, T; Ceradini, F; Ciambrone, P; De Lucia, E; De Santis, A; De Simone, P; De Zorzi, G; Denig, A; Di Domenico, A; Di Donato, C; Di Micco, B; Dreucci, M; Felici, G; Fiore, S; Franzini, P; Gatti, C; Gauzzi, P; Giovannella, S; Graziani, E; Lanfranchi, G; Lee-Franzini, J; Martini, M; Massarotti, P; Meola, S; Miscetti, S; Moulson, M; Müller, S; Murtas, F; Napolitano, M; Nguyen, F; Palutan, M; Pasqualucci, E; Passeri, A; Patera, V; Santangelo, P; Sciascia, B; Spadaro, T; Testa, M; Tortora, L; Valente, P; Venanzoni, G; Versaci, R; Xu, G

    2009-01-01

    We have searched for the decay phi -> K0 K0bar gamma, by detecting K_s pairs plus a photon and with the K_s-mesons decaying to pi^+ pi^-, in a sample of about 1.5x 10^9 phi-decays collected by the KLOE experiment at DAFNE. The reaction proceeds through the intermediate states f_0(980) gamma, a_0(980) gamma. We find five events with 3.2 events expected from background processes. We obtain the upper limit: BR (phi -> K0 K0bar gamma) < 1.9x10^-8 at 90% C.L. .

  5. Evaluation experiments on related terms search in Wikipedia: Information Content and Adapted HITS (In Russian)

    CERN Document Server

    Krizhanovsky, A A

    2007-01-01

    The classification of metrics and algorithms search for related terms via WordNet, Roget's Thesaurus, and Wikipedia is proposed. Evaluation experiments on Information Content and adapted HITS algorithm are described. The test collection of Russian word pairs with human-assigned similarity judgments is proposed. ----- Predlozhena klassifikacija metrik i algoritmov poiska semanticheski blizkih slov v tezaurusah WordNet, Rozhe i jenciklopedii Vikipedija. S pomow'ju jeksperimentov v Vikipedii oceneny metrika Information Content i adaptirovannyj algoritm HITS. Predlozhen resurs dlja ocenki semanticheskoj blizosti russkih slov.

  6. Latest Results of the OSQAR Photon Regeneration Experiment for Axion-Like Particle Search

    OpenAIRE

    Ballou, Rafik; Deferne, Guy; Kral, Miroslav; Kunc, Stepan; Macuchova, Karolina; Meissner, Krzysztof A.; Morville, Jérôme; Pugnat, Pierre; Romanini, Daniele; Schott, Matthias; Siemko, Andrzej; Slunecka, Miloslav; Duvillaret, Lionel; Sulc, Miroslav; Vitrant, Guy

    2014-01-01

    The OSQAR photon regeneration experiment searches for pseudoscalar and scalar axion-like particles by the method of ``Light Shining Through a Wall'', based on the assumption that these weakly interacting sub-eV particles couple to two photons to give rise to quantum oscillations with optical photons in strong magnetic field. No excess of events has been observed, which constrains the di-photon coupling strength of both pseudoscalar and scalar particles down to $5.7 \\cdot 10^{-8}$ GeV$^{-1}$ i...

  7. CALIS - a CALibration Insertion System for the DarkSide-50 dark matter search experiment

    Energy Technology Data Exchange (ETDEWEB)

    Agnes, P.; et al.

    2012-12-28

    This paper describes the design, fabrication, commissioning and use of a CALibration source Insertion System (CALIS) in the DarkSide-50 direct dark matter search experiment. CALIS deploys radioactive sources into the liquid scintillator veto to characterize the detector response and detection efficiency of the DarkSide-50 Liquid Argon Time Projection Chamber, and the surrounding 30 t organic liquid scintillator neutron veto. It was commissioned in September 2014 and has been used successfully in several gamma and neutron source campaigns since then. A description of the hardware and an excerpt of calibration analysis results are given below.

  8. CALIS - a CALibration Insertion System for the DarkSide-50 dark matter search experiment

    CERN Document Server

    Agnes, P; Alexander, T; Alton, A K; Asner, D M; Back, H O; Baldin, B; Biery, K; Bocci, V; Bonfini, G; Bonivento, W; Bossa, M; Bottino, B; Brigatti, A; Brodsky, J; Budano, F; Bussino, S; Cadeddu, M; Cadonati, L; Cadoni, M; Calaprice, F; Canci, N; Candela, A; Caravati, M; Cariello, M; Carlini, M; Catalanotti, S; Cavalcante, P; Chepurnov, A; Cicalo, C; Cocco, A G; Covone, G; D'Angelo, D; D'Incecco, M; Davini, S; De Cecco, S; De Deo, M; De Vincenzi, M; Derbin, A; Devoto, A; Di Eusanio, F; Di Pietro, G; Dionisi, C; Edkins, E; Empl, A; Fan, A; Fiorillo, G; Fomenko, K; Forster, G; Franco, D; Gabriele, F; Galbiati, C; Giagu, S; Giganti, C; Giovanetti, G K; Goretti, A M; Granato, F; Grandi, L; Gromov, M; Guan, M; Guardincerri, Y; Hackett, B R; Herner, K; Hughes, D; Humble, P; Hungerford, E V; Ianni, Al; Ianni, An; James, I; Johnson, T N; Jollet, C; Keeter, K; Kendziora, C L; Koh, G; Korablev, D; Korga, G; Kubankin, A; Li, X; Lissia, M; Loer, B; Lombardi, P; Longo, G; Ma, Y; Machulin, I N; Mandarano, A; Mari, S M; Maricic, J; Marini, L; Martoff, C J; Meregaglia, A; Meyers, P D; Milincic, R; Miller, J D; Montanari, D; Monte, A; Mount, B J; Muratova, V N; Musico, P; Napolitano, J; Agasson, A Navrer; Odrowski, S; Orsini, M; Ortica, F; Pagani, L; Pallavicini, M; Pantic, E; Parmeggiano, S; Pelczar, K; Pelliccia, N; Pocar, A; Pordes, S; Pugachev, D A; Qian, H; Randle, K; Ranucci, G; Razeti, M; Razeto, A; Reinhold, B; Renshaw, A L; Rescigno, M; Riffard, Q; Romani, A; Rossi, B; Rossi, N; Rountree, D; Sablone, D; Saggese, P; Saldanha, R; Sands, W; Savarese, C; Schlitzer, B; Segreto, E; Semenova, D A; Shields, E; Singh, P N; Skorokhvatov, M D; Smirnov, O; Sotnikov, A; Stanford, C; Suvorov, Y; Tartaglia, R; Tatarowicz, J; Testera, G; Tonazzo, A; Trinchese, P; Unzhakov, E V; Verducci, M; Vishneva, A; Vogelaar, B; Wada, M; Walker, S; Wang, H; Wang, Y; Watson, A W; Westerdale, S; Wilhelmi, J; Wojcik, M M; Xiang, Xi; Xiao, X; Xu, J; Yang, C; Zec, A; Zhong, W; Zhu, C; Zuzel, G

    2016-01-01

    This paper describes the design, fabrication, commissioning and use of a CALibration source Insertion System (CALIS) in the DarkSide-50 direct dark matter search experiment. CALIS deploys radioactive sources into the liquid scintillator veto to characterize the detector response and detection efficiency of the DarkSide-50 Liquid Argon Time Projection Chamber, and the surrounding 30 t organic liquid scintillator neutron veto. It was commissioned in September 2014 and has been used successfully in several gamma and neutron source campaigns since then. A description of the hardware and an excerpt of calibration analysis results are given below.

  9. Search for Intermediate Mass Magnetic Monopoles and Nuclearites with the SLIM experiment

    CERN Document Server

    Cecchini, S; Ferdinando, D D; Cozzi, M; Frutti, M; Giacomelli, G; Kumar, A; Manzoor, S; McDonald, J; Medinaceli, E; Nogales, J; Patrizii, L; Pinfold, J L; Popa, V; Qureshi, I E; Saavedra, O; Sher, G; Shahzad, M I; Spurio, M; Ticona, R; Togo, V; Velarde, A

    2005-01-01

    SLIM is a large area experiment (440 m2) installed at the Chacaltaya cosmic ray laboratory since 2001, and about 100 m2 at Koksil, Himalaya, since 2003. It is devoted to the search for intermediate mass magnetic monopoles (107-1013 GeV/c2) and nuclearites in the cosmic radiation using stacks of CR39 and Makrofol nuclear track detectors. In four years of operation it will reach a sensitivity to a flux of about 10-15 cm-2 s-1 sr-1. We present the results of the calibration of CR39 and Makrofol and the analysis of a first sample of the exposed detector.

  10. Identification of Radiopure Titanium for the LZ Dark Matter Experiment and Future Rare Event Searches

    Energy Technology Data Exchange (ETDEWEB)

    Akerib, D.S.; et al.

    2017-02-08

    The LUX-ZEPLIN (LZ) experiment will search for dark matter particle interactions with a detector containing a total of 10 tonnes of liquid xenon within a double-vessel cryostat. The large mass and proximity of the cryostat to the active detector volume demand the use of material with extremely low intrinsic radioactivity. We report on the radioassay campaign conducted to identify suitable metals, the determination of factors limiting radiopure production, and the selection of titanium for construction of the LZ cryostat and other detector components. This titanium has been measured with activities of $^{238}$U$_{e}$~$<$1.6~mBq/kg, $^{238}$U$_{l}$~$<$0.09~mBq/kg, $^{232}$Th$_{e}$~$=0.28\\pm 0.03$~mBq/kg, $^{232}$Th$_{l}$~$=0.25\\pm 0.02$~mBq/kg, $^{40}$K~$<$0.54~mBq/kg, and $^{60}$Co~$<$0.02~mBq/kg (68\\% CL). Such low intrinsic activities, which are some of the lowest ever reported for titanium, enable its use for future dark matter and other rare event searches. Monte Carlo simulations have been performed to assess the expected background contribution from the LZ cryostat with this radioactivity. In 1,000 days of WIMP search exposure of a 5.6-tonne fiducial mass, the cryostat will contribute only a mean background of $0.160\\pm0.001$(stat)$\\pm0.030$(sys) counts.

  11. Medical Support for Aircraft Disaster Search and Recovery Operations at Sea: the RSN Experience.

    Science.gov (United States)

    Teo, Kok Ann Colin; Chong, Tse Feng Gabriel; Liow, Min Han Lincoln; Tang, Kong Choong

    2016-06-01

    The maritime environment presents a unique set of challenges to search and recovery (SAR) operations. There is a paucity of information available to guide provision of medical support for SAR operations for aircraft disasters at sea. The Republic of Singapore Navy (RSN) took part in two such SAR operations in 2014 which showcased the value of a military organization in these operations. Key considerations in medical support for similar operations include the resultant casualty profile and challenges specific to the maritime environment, such as large distances of area of operations from land, variable sea states, and space limitations. Medical support planning can be approached using well-established disaster management life cycle phases of preparedness, mitigation, response, and recovery, which all are described in detail. This includes key areas of dedicated training and exercises, force protection, availability of air assets and chamber support, psychological care, and the forensic handling of human remains. Relevant lessons learned by RSN from the Air Asia QZ8501 search operation are also included in the description of these key areas. Teo KAC , Chong TFG , Liow MHL , Tang KC . Medical support for aircraft disaster search and recovery operations at sea: the RSN experience. Prehosp Disaster Med. 2016; 31(3):294-299.

  12. Use of human remains detection dogs for wide area search after wildfire: a new experience for TexasTask Force 1 Search and Rescue resources.

    Science.gov (United States)

    Migala, Alexandre F; Brown, Susann E

    2012-12-01

    In September 2011, wildfires in Bastrop County, TX, were the most destructive in the state's history, consuming more than 34000 acres (13759 hectares) and more than 1600 homes in the process. The wildfires began by consuming more than 30 homes across 2 miles (3.2 km) in 17 minutes, raising the fear that local residents may not have had sufficient time to escape the conflagration. Texas Task Force 1 deployed for a new mission, the search and recovery of human remains. Although there have been other larger and more widespread fires in the past, it was the speed at which this fire spread that created the environment requiring such a search. The mission was focused primarily on human detection, searching an area almost 72 square miles (186 km(2)) between September 7 and 11, 2011. To our knowledge, never before have human remains detection dogs been tasked with such an undertaking. Lessons learned from this event will educate all levels of government agencies, emergency medical services, fire departments, law enforcement, utilities, veterinary services, and search and rescue/recovery activities in the future. The utilization of human remains detection canines integrated with search teams trained in larger scale events is one such area that will benefit from this experience, with a final area searched of 15 598 acres (6312 hectares). Copyright © 2012 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

  13. GRBs search results with the ARGO-YBJ experiment operated in Scaler Mode

    CERN Document Server

    Sciascio, G D

    2006-01-01

    The ARGO-YBJ experiment is almost completely installed at the YangBaJing Cosmic Ray Laboratory (4300 m a.s.l., Tibet, P.R. China). The lower energy limit of the detector (E $\\sim$ 1 GeV) is reached with the scaler mode, i.e., recording the single particle rate at fixed time intervals. In this technique, due to its high altitude location and large area ($\\sim$ 6700 m$^2$), this experiment is the most sensitive among all present and past ground-based detectors. In the energy range under investigation, signals due to local (e.g. solar GLEs) and cosmological (e.g. GRBs) phenomena are expected as significant enhancements of the counting rate over the background. Results on the search for GRBs in coincidence with satellite detections are presented.

  14. The current status of "Troitsk nu-mass" experiment in search for sterile neutrino

    CERN Document Server

    Abdurashitov, D N; Berlev, A I; Chernov, V G; Geraskin, E V; Golubev, A A; Koroteev, G A; Likhovid, N A; Lokhov, A A; Markin, A I; Nozik, A A; Pantuev, V S; Parfenov, V I; Skasyrskaya, A K; Titov, N A; Tkachev, I I; Tkachov, F V; Zadorozhny, S V

    2015-01-01

    We propose a new experiment to search for a sterile neutrino in a few keV mass range at the "Troitsk nu-mass" facility. The expected signature corresponds to a kink in the electron energy spectrum in tritium beta-decay. The new goal compared to our previous experiment will be precision spectrum measurements well below end point. The experimental installation consists of a windowless gaseous tritium source and a high resolution electromagnetic spectrometer. We estimate that the current bounds on the sterile neutrino mixing parameter can be improved by an order of magnitude in the mass range under 5 keV without major upgrade of the existing equipment. Upgrades of calibration, data acquisition and high voltage systems will allow to improve the bounds by another order of magnitude.

  15. On search for eV hidden sector photons in Super-Kamiokande and CAST experiments

    Energy Technology Data Exchange (ETDEWEB)

    Gninenko, S.N. [Russian Academy of Sciences, Moscow (Russian Federation). Inst. for Nuclear Research; Redondo, J. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2008-04-15

    If light hidden sector photons ({gamma}'s) exist, they could be produced through kinetic mixing with solar photons in the eV energy range. We propose to search for this hypothetical {gamma}'-flux with the Super-Kamiokande and/or upgraded CAST detectors. The proposed experiments are sensitive to the {gamma}-{gamma}' mixing strength as small as 10{sup -5}>or similar {chi}>or similar 10{sup -9} for the {gamma}'' mass region 10{sup -4} experiments for this mass region. (orig.)

  16. A novel experiment searching for the lepton flavour violating decay mu -> eee

    CERN Document Server

    Berger, Niklaus

    2011-01-01

    Since the discovery of neutrino oscillations it is known that lepton flavour is not conserved. Lepton flavour violating processes in the charged lepton sector have so far however eluded detection; as they are heavily suppressed in the standard model of particle physics, an observation would be a clear signal for new physics and help to understand the source of neutrino masses and CP violation. We propose a novel experiment searching for the decay mu -> eee with the aim of ultimately reaching a sensitivity of 10^-16, an improvement by four orders of magnitude compared to previous experiments. The technologies enabling this step are thin high-voltage monolithic active pixel sensors for precise tracking at high rates with a minimum of material and scintillating fibres for high resolution time measurements.

  17. A novel experiment searching for the lepton flavour violating decay μ → eee

    Science.gov (United States)

    Berger, Niklaus

    2013-02-01

    Since the discovery of neutrino oscillations it is known that lepton flavour is not conserved. Lepton flavour violating processes in the charged lepton sector have so far however eluded detection; as they are heavily suppressed in the standard model of particle physics, an observation would be a clear signal for new physics and help to understand the source of neutrino masses and CP violation. We propose a novel experiment searching for the decay μ → eee with the aim of ultimately reaching a sensitivity of 10-16, an improvement by four orders of magnitude compared to previous experiments. The technologies enabling this step are thin high-voltage monolithic active pixel sensors for precise tracking at high rates with a minimum of material and scintillating fibres for high resolution time measurements.

  18. The NEXT experiment: A high pressure xenon gas TPC for neutrinoless double beta decay searches

    CERN Document Server

    Lorca, D; Monrabal, F

    2012-01-01

    Neutrinoless double beta decay is a hypothetical, very slow nuclear transition in which two neutrons undergo beta decay simultaneously and without the emission of neutrinos. The importance of this process goes beyond its intrinsic interest: an unambiguous observation would establish a Majorana nature for the neutrino and prove the violation of lepton number. NEXT is a new experiment to search for neutrinoless double beta decay using a radiopure high-pressure xenon gas TPC, filled with 100 kg of Xe enriched in Xe-136. NEXT will be the first large high-pressure gas TPC to use electroluminescence readout with SOFT (Separated, Optimized FuncTions) technology. The design consists in asymmetric TPC, with photomultipliers behind a transparent cathode and position-sensitive light pixels behind the anode. The experiment is approved to start data taking at the Laboratorio Subterr\\'aneo de Canfranc (LSC), Spain, in 2014.

  19. The Search for Fractional Charge Particles in an Advanced, Automated Variation of the Millikan Experiment

    Science.gov (United States)

    Lee, I. T.; Halyo, V.; Lee, E. R.; Loomba, D.; Perl, M. L.

    2001-04-01

    We will present a variation on the Millikan apparatus designed to look for fractionally charged particles in bulk materials, and results from the current run. Oil drops are produced from a drop-on-demand ejector, and imaged by a digital CCD camera and framegrabber combination. A networked Linux cluster is used to simultaneously collect and analyze data, and to monitor and control the apparatus. The experiment is fully automated, and utilizes laminar air flow to make possible the accurate measurements of charge on large (20 micron) fluid drops. The experiment has the capability to process a total of 10^7 to 10^8 drops (20-200 mg), and the ability to use large drops enables the search to be carried out in mineral suspensions.

  20. Search for New Light Higgs Bosons in Boosted Tau Final States with the CMS Experiment

    CERN Document Server

    AUTHOR|(CDS)2081769

    In this dissertation, I present a search for non-standard decays of a Standard Model-likeHiggs boson to pairs of light bosons, as predicted in models with extended Higgs sectors.In two Higgs doublet models, including the next-to-minimal supersymmetric standardmodel, the Higgs boson can decay into a pair of light pseudoscalars a.In this search, the gluon fusion, W and Z associated Higgs, and vector boson fusionproduction channels for the Higgs are all considered, and the decay H →aa with a → τ τis reconstructed from the tau decay products. The final state is characterized by oneisolated high pT muon plus at least one highly boosted pair of taus, of which one of thetaus is required to decay to a muon.Using 19.7 fb−1 of 8 TeV center of mass pp collision data recorded by the CompactMuon Solenoid experiment at the Large Hadron Collider, a counting experiment is performed in a region of high di-tau invariant mass. We have found no excess of events abovethe Standard Model backgrounds, and the observed data ...

  1. An Experiment and Detection Scheme for Cavity-Based Light Cold Dark Matter Particle Searches

    Directory of Open Access Journals (Sweden)

    Masroor H. S. Bukhari

    2017-01-01

    Full Text Available A resonance detection scheme and some useful ideas for cavity-based searches of light cold dark matter particles (such as axions are presented, as an effort to aid in the on-going endeavors in this direction as well as for future experiments, especially in possibly developing a table-top experiment. The scheme is based on our idea of a resonant detector, incorporating an integrated tunnel diode (TD and GaAs HEMT/HFET (High-Electron Mobility Transistor/Heterogeneous FET transistor amplifier, weakly coupled to a cavity in a strong transverse magnetic field. The TD-amplifier combination is suggested as a sensitive and simple technique to facilitate resonance detection within the cavity while maintaining excellent noise performance, whereas our proposed Halbach magnet array could serve as a low-noise and permanent solution replacing the conventional electromagnets scheme. We present some preliminary test results which demonstrate resonance detection from simulated test signals in a small optimal axion mass range with superior signal-to-noise ratios (SNR. Our suggested design also contains an overview of a simpler on-resonance dc signal read-out scheme replacing the complicated heterodyne read-out. We believe that all these factors and our propositions could possibly improve or at least simplify the resonance detection and read-out in cavity-based DM particle detection searches (and other spectroscopy applications and reduce the complications (and associated costs, in addition to reducing the electromagnetic interference and background.

  2. Cryogenic phonon-scintillation detectors with PMT readout for rare event search experiments

    Science.gov (United States)

    Zhang, X.; Lin, J.; Mikhailik, V. B.; Kraus, H.

    2016-06-01

    Cryogenic phonon-scintillation detectors (CPSD) for rare event search experiments require reliable, efficient and robust photon detectors that can resolve individual photons in a scintillation event. We report on a cryogenic detector containing a scintillating crystal, equipped with an NTD-Ge phonon sensor and a photon detector based on a low-temperature photomultiplier tube (PMT) that is powered by a Cockcroft-Walton generator. Here we present results from the characterisation of two detector modules, one with CaWO4, the other with CaMoO4 as scintillator. The energy resolutions (FWHM) at 122.1 keV for the scintillation/PMT channel are 19.9% and 29.7% respectively for CaWO4 and CaMoO4 while the energy resolutions (FWHM) for the phonon channels are 2.17 keV (1.8%) and 0.97 keV (0.79%). These characteristics compare favourably with other CPSDs currently used in cryogenic rare-event search experiments. The detection module with PMT readout benefits from the implementation of a well-understood, reliable, and commercially available component and improved time resolution, while retaining the major advantages of conventional CPSD, such as high sensitivity, resolving power and discrimination ability.

  3. The NEXT-100 experiment for neutrinoless double beta decay searches (Conceptual Design Report)

    CERN Document Server

    Álvarez, V; Batallé, M; Bayarri, J; Borges, F I G; Cárcel, S; Carmona, J M; Castel, J; Catalá, J M; Cebrián, S; Cervera-Villanueva, A; Chan, D; Conde, C A N; Dafni, T; Dias, T H V T; Díaz, J; Esteve, R; Evtoukhovitch, P; Fernandes, L M P; Ferrario, P; Ferrer-Ribas, E; Ferreira, A L; Freitas, E D C; Gil, A; Giomataris, I; Goldschmidt, A; Gómez, E; Gómez, H; Gómez-Cadenas, J J; Gónzález, K; Gutiérrez, R M; Hernando-Morata, J A; Herrera, D C; Herrero, V; Iguaz, F; Irastorza, I G; Kalinnikov, V; Kustov, A; Liubarsky, I; Lopes, J A M; Lorca, D; Losada, M; Luzón, G; Martín-Albo, J; Méndez, A; Miller, T; Moisenko, A; Mols, J P; Monrabal, F; Monteiro, C M B; Monzó, J M; Mora, F J; Muñoz-Vidal, J; da Luz, H Natal; Navarro, G; Nebot, M; Nygren, D; Oliveira, C A B; Palma, R; Pérez-Aparicio, J L; Renner, J; Ripoll, L; Rodríguez, A; Rodríguez, J; Santos, F P; Santos, J M F dos; Seguí, L; Serra, L; Sofka, C; Sorel, M; Spieler, H; Toledo, J F; Tomás, A; Tsamalaidze, Z; Vázquez, D; Velicheva, E; Veloso, J F C A; Villar, J A; Webb, R; Weber, T; White, J; Yahlali, N

    2011-01-01

    We propose an EASY (Electroluminescent ApparatuS of high Yield) and SOFT (Separated Optimized FuncTion) time-projection chamber for the NEXT experiment, that will search for neutrinoless double beta decay (bb0nu) in Xe-136. Our experiment must be competitive with the new generation of bb0nu searches already in operation or in construction. This requires a detector with very good energy resolution (<1%), very low background con- tamination (1E-4 counts/(keV \\bullet kg \\bullet y)) and large target mass. In addition, it needs to be operational as soon as possible. The design described here optimizes energy resolution thanks to the use of proportional electroluminescent amplification (EL); it is compact, as the Xe gas is under high pressure; and it allows the measurement of the topological signature of the event to further reduce the background contamination. The SOFT design uses different sensors for tracking and calorimetry. We propose the use of SiPMs (MPPCs) coated with a suitable wavelength shifter for th...

  4. Operating the GridPix detector in dark matter search experiments

    Energy Technology Data Exchange (ETDEWEB)

    Schön, R., E-mail: rolfs@nikhef.nl [National Institute for Subatomic Physics Nikhef, Science Park 105, 1098 XG, Amsterdam (Netherlands); Alfonsi, M. [National Institute for Subatomic Physics Nikhef, Science Park 105, 1098 XG, Amsterdam (Netherlands); Hemink, G. [National Institute for Subatomic Physics Nikhef, Science Park 105, 1098 XG, Amsterdam (Netherlands); University of Twente, Drienerloolaan 5, 7522 NB, Enschede (Netherlands); Decowski, M.P.; Bakel, N. van; Graaf, H. van der [National Institute for Subatomic Physics Nikhef, Science Park 105, 1098 XG, Amsterdam (Netherlands)

    2013-08-01

    The DARWIN (dark matter WIMP search with noble liquids) design study aims to use liquid argon and liquid xenon targets to look for nuclear recoils due to weakly interacting massive particles (WIMPs). To measure the recoil energy in dual-phase noble gas time projection chambers the combination of scintillation and ionisation detection is used to discriminate nuclear from electron recoils. Current experiments use an array of photomultiplier tubes to detect the primary scintillation and the ionisation electrons via secondary scintillation in the gas phase. Within the research framework for DARWIN, one candidate for an alternative direct charge readout is GridPix, a micro-pattern gaseous detector composed of a Micromegas-like amplification grid over the Timepix 65k pixel readout chip. It can achieve a single-electron detection efficiency of up to 98% and has thus great potential to identify the ionisation electrons in dark matter search experiments. The main challenges for this application are low outgassing, thermal robustness, and operation in pure (thus quencher-free) noble gas. To investigate its applicability we operated a GridPix detector in an argon cryostat. We proved GridPix's performance in pure argon. The gas amplification was confirmed in pure argon in the broad temperature range from 300 K down to 87 K. Additionally, we discuss results of thermal tests of GridPix devices at liquid xenon temperature in a dry nitrogen atmosphere.

  5. On the possibility of performing an experiment in the search for a sterile neutrino

    Science.gov (United States)

    Serebrov, A. P.; Fomin, A. K.; Zinoviev, V. G.; Ivochkin, V. G.; Loginov, Yu. E.; Petrov, G. A.; Solovey, V. A.; Chernyi, A. V.; Zherebtsov, O. M.; Samoylov, R. M.; Martemyanov, V. P.; Tsinoev, V. G.; Tarasenkov, V. G.; Aleshin, V. I.; Petelin, A. L.; Pavlov, S. V.; Svyatkin, M. N.; Izhutov, A. L.; Sazontov, S. A.; Ryazanov, D. K.; Gromov, M. O.; Afanasiev, V. V.; Rykalin, V. I.

    2014-06-01

    At present, the possible existence of a sterile neutrino having a significantly smaller cross section of interaction with a substance than, for example, electronic antineutrinos from a reactor is being widely discussed. It has been suggested that, due to reactor antineutrino transition into a sterile state, one can observe both the oscillation effect at short distances (5-15 m) from the reactor and a deficiency of the reactor antineutrino flux at large distances. We have investigated the possibility of performing experiments in search for reactor antineutrino oscillations into a sterile state on research reactors. A model experiment has been carried out on a 16-MW WWR-M reactor at the Petersburg Nuclear Physics Institute with a view to implementing a full-scale experiment using a 100-MW SM-3 reactor at the Research Institute of Atomic Reactors (RIAR). Background conditions of these experiments have been studied for both reactors. It is concluded that the implementation of a full-scale Neutrino-4 experiment on the SM-3 reactor at the RIAR is possible.

  6. Optimizing light-shining-through-a-wall experiments for axion and other WISP searches

    Energy Technology Data Exchange (ETDEWEB)

    Arias, Paola; Ringwald, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Jaeckel, Joerg [Durham Univ. (United Kingdom). Inst. for Particle Physics Phenomenology; Redondo, Javier [Max-Planck-Institut fuer Physik, Muenchen (Germany)

    2010-10-15

    One of the prime tools to search for new light bosons interacting very weakly with photons - prominent examples are axions, axion-like particles and extra ''hidden'' U(1) gauge bosons - are light-shining-through-a-wall (LSW) experiments. With the current generation of these experiments finishing data taking it is time to plan for the next and search for an optimal setup. The main challenges are clear: on the one hand we want to improve the sensitivity towards smaller couplings, on the other hand we also want to increase the mass range to which the experiments are sensitive. Our main example are axion(-like particle)s but we also discuss implications for other WISPs (weakly interacting slim particles) such as hidden U(1) gauge bosons. To improve the sensitivity for axions towards smaller couplings one can use multiple magnets to increase the length of the interaction region. However, naively the price to pay is that the mass range is limited to smaller masses. We discuss how one can optimize the arrangement of magnets (both in field direction as well as allowing for possible gaps in between) to ameliorate this problem. Moreover, future experiments will include resonant, high quality optical cavities in both the production and the regeneration region. To achieve the necessary high quality of the cavities we need to avoid too high diffraction losses. This leads to minimum requirements on the diameter of the laser beam and therefore on the aperture of the cavity. We investigate what can be achieved with currently available magnets and desirable features for future ones. (orig.)

  7. Infrared Counterparts to Chandra X-Ray Sources in the Antennae

    CERN Document Server

    Clark, D M; Brandl, B R; Wilson, J C; Carson, J C; Henderson, C P; Hayward, T L; Barry, D J; Ptak, A F; Colbert, E J M

    2006-01-01

    We use deep J and Ks images of the Antennae (NGC 4038/9) obtained with WIRC on the Palomar 200-inch telescope, together with the Chandra X-ray source list of Zezas et al. (2002a), to search for IR counterparts to X-ray point sources. We establish an X-ray/IR astrometric frame tie with 0.5" rms residuals over a \\~4.3' field. We find 13 ``strong'' IR counterparts brighter than Ks = 17.8 mag and < 1.0" from X-ray sources, and an additional 6 ``possible'' IR counterparts between 1.0" and 1.5" from X-ray sources. The surface density of IR sources near the X-ray sources suggests only ~2 of the ``strong'' counterparts and ~3 of the ``possible'' counterparts are chance superpositions of unrelated objects. Comparing both strong and possible IR counterparts to our photometric study of ~220 Antennae, IR clusters, we find the IR counterparts to X-ray sources are \\~1.2 mag more luminous in Ks than average non-X-ray clusters. We also note that the X-ray/IR matches are concentrated in the spiral arms and ``overlap'' regi...

  8. Over the top: Experiment and the testing of hypotheses in the search for the top quark

    Science.gov (United States)

    Staley, Kent Wade

    1998-07-01

    This study presents a historical account of experiments, performed by the Collider Detector at Fermilab (CDF) collaboration, which led to the discovery of the top quark, and a discussion of philosophical issues raised by that episode. The historical discussion is based on published and unpublished documents and oral history interviews, and is presented in two parts: First, the formation of the collaboration and construction of the detector are described. The activities of the collaborators during the period of detector construction are described in terms of the development of resources for a general experimental programme. Second, the development of the means of analyzing the data for the top quark search is described, particularly aspects of the analysis that were disputed. The hypothesis that collaboration researchers have come to regard the social process of resolving disputes as a matter of methodological importance is suggested. The philosophical discussion of the experiment employs the hierarchy of models approach of Patrick Suppes and Deborah Mayo in order to examine the logic of hypothesis testing and draw some conclusions regarding the nature of scientific evidence. In an extension of an argument presented by Peter Achinstein, the account of hypothesis testing given by hypothetico-deductivist philosophers such as Karl Popper and R. B. Braithwaite is examined in light of the reasoning employed in the top search, and is found wanting. The prediction based on the hypothesis being tested in the top search is found to have been inferred inductively from the experimental data. Finally, a discussion is presented of tuning on the signal, a form of bias in the testing of hypotheses. The proscription of this form of bias resembles John Worrall's requirement of use novelty, but is shown instead to serve the aim of devising a test of the hypothesis that is severe, in the sense articulated by Deborah Mayo. It is shown that the evaluation of evidence claims, as it

  9. Fast radio bursts counterparts in the scenario of supergiant pulses

    Science.gov (United States)

    Popov, S. B.; Pshirkov, M. S.

    2016-10-01

    We discuss identification of possible counterparts and persistent sources related to fast radio bursts (FRBs) in the framework of the model of supergiant pulses from young neutron stars with large spin-down luminosities. In particular, we demonstrate that at least some of the sources of FRBs can be observed as ultraluminous X-ray sources (ULXs). At the moment no ULXs are known to be coincident with localization areas of FRBs. We searched for a correlation of FRB positions with galaxies in the 2MASS Redshift survey catalogue. Our analysis produced statistically insignificant overabundance (p-value ≈ 4 per cent) of galaxies in error boxes of FRBs. In the very near future with even modestly increased statistics of FRBs and with the help of dedicated X-ray observations and all-sky X-ray surveys it will be possible to decisively prove or falsify the supergiant pulses model.

  10. Search Patterns

    CERN Document Server

    Morville, Peter

    2010-01-01

    What people are saying about Search Patterns "Search Patterns is a delight to read -- very thoughtful and thought provoking. It's the most comprehensive survey of designing effective search experiences I've seen." --Irene Au, Director of User Experience, Google "I love this book! Thanks to Peter and Jeffery, I now know that search (yes, boring old yucky who cares search) is one of the coolest ways around of looking at the world." --Dan Roam, author, The Back of the Napkin (Portfolio Hardcover) "Search Patterns is a playful guide to the practical concerns of search interface design. It cont

  11. Liverpool Telescope follow-up of candidate electromagnetic counterparts during the first run of Advanced LIGO

    CERN Document Server

    Copperwheat, C M; Piascik, A S; Bersier, D; Bode, M F; Collins, C A; Darnley, M J; Galloway, D K; Gomboc, A; Kobayashi, S; Lamb, G P; Levan, A J; Mazzali, P A; Mundell, C G; Pian, E; Pollacco, D; Steeghs, D; Tanvir, N R; Ulaczyk, K; Wiersema, K

    2016-01-01

    The first direct detection of gravitational waves was made in late 2015 with the Advanced LIGO detectors. By prior arrangement, a worldwide collaboration of electromagnetic follow-up observers were notified of candidate gravitational wave events during the first science run, and many facilities were engaged in the search for counterparts. No counterparts were identified, which is in line with expectations given that the events were classified as black hole - black hole mergers. However these searches laid the foundation for similar follow-up campaigns in future gravitational wave detector science runs, in which the detection of neutron star merger events with observable electromagnetic counterparts is much more likely. Three alerts were issued to the electromagnetic collaboration over the course of the first science run, which lasted from September 2015 to January 2016. Two of these alerts were associated with the gravitational wave events since named GW150914 and GW151226. In this paper we provide an overvie...

  12. Improved Search for a Light Sterile Neutrino with the Full Configuration of the Daya Bay Experiment.

    Science.gov (United States)

    An, F P; Balantekin, A B; Band, H R; Bishai, M; Blyth, S; Cao, D; Cao, G F; Cao, J; Cen, W R; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chen, H S; Chen, Q Y; Chen, S M; Chen, Y X; Chen, Y; Cheng, J-H; Cheng, J; Cheng, Y P; Cheng, Z K; Cherwinka, J J; Chu, M C; Chukanov, A; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, X F; Ding, Y Y; Diwan, M V; Dolgareva, M; Dove, J; Dwyer, D A; Edwards, W R; Gill, R; Gonchar, M; Gong, G H; Gong, H; Grassi, M; Gu, W Q; Guan, M Y; Guo, L; Guo, R P; Guo, X H; Guo, Z; Hackenburg, R W; Han, R; Hans, S; He, M; Heeger, K M; Heng, Y K; Higuera, A; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, T; Hu, W; Huang, E C; Huang, H X; Huang, X T; Huber, P; Huo, W; Hussain, G; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiao, J B; Johnson, R A; Joshi, J; Kang, L; Kettell, S H; Kohn, S; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Langford, T J; Lau, K; Lebanowski, L; Lee, J; Lee, J H C; Lei, R T; Leitner, R; Leung, J K C; Li, C; Li, D J; Li, F; Li, G S; Li, Q J; Li, S; Li, S C; Li, W D; Li, X N; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, S; Lin, S K; Lin, Y-C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, J L; Liu, J C; Loh, C W; Lu, C; Lu, H Q; Lu, J S; Luk, K B; Lv, Z; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; Malyshkin, Y; Martinez Caicedo, D A; McDonald, K T; McKeown, R D; Mitchell, I; Mooney, M; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevskiy, A; Pan, H-R; Park, J; Patton, S; Pec, V; Peng, J C; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Steiner, H; Sun, G X; Sun, J L; Tang, W; Taychenachev, D; Treskov, K; Tsang, K V; Tull, C E; Viaux, N; Viren, B; Vorobel, V; Wang, C H; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, X; Wang, Y F; Wang, Z; Wang, Z; Wang, Z M; Wei, H Y; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, C-H; Wu, Q; Wu, W J; Xia, D M; Xia, J K; Xing, Z Z; Xu, J Y; Xu, J L; Xu, Y; Xue, T; Yang, C G; Yang, H; Yang, L; Yang, M S; Yang, M T; Ye, M; Ye, Z; Yeh, M; Young, B L; Yu, Z Y; Zeng, S; Zhan, L; Zhang, C; Zhang, H H; Zhang, J W; Zhang, Q M; Zhang, X T; Zhang, Y M; Zhang, Y X; Zhang, Y M; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y B; Zhong, W L; Zhou, L; Zhou, N; Zhuang, H L; Zou, J H

    2016-10-07

    This Letter reports an improved search for light sterile neutrino mixing in the electron antineutrino disappearance channel with the full configuration of the Daya Bay Reactor Neutrino Experiment. With an additional 404 days of data collected in eight antineutrino detectors, this search benefits from 3.6 times the statistics available to the previous publication, as well as from improvements in energy calibration and background reduction. A relative comparison of the rate and energy spectrum of reactor antineutrinos in the three experimental halls yields no evidence of sterile neutrino mixing in the 2×10^{-4}≲|Δm_{41}^{2}|≲0.3  eV^{2} mass range. The resulting limits on sin^{2}2θ_{14} are improved by approx imately a factor of 2 over previous results and constitute the most stringent constraints to date in the |Δm_{41}^{2}|≲0.2  eV^{2} region.

  13. Low radioactivity argon dark matter search results from the DarkSide-50 experiment

    CERN Document Server

    Agnes, P; Albuquerque, I F M; Alexander, T; Alton, A K; Arisaka, K; Back, H O; Baldin, B; Biery, K; Bonfini, G; Bossa, M; Bottino, B; Brigatti, A; Brodsky, J; Budano, F; Bussino, S; Cadeddu, M; Cadonati, L; Cadoni, M; Calaprice, F; Canci, N; Candela, A; Cao, H; Cariello, M; Carlini, M; Catalanotti, S; Cavalcante, P; Chepurnov, A; Cocco, A G; Covone, G; Crippa, L; D'Angelo, D; D'Incecco, M; Davini, S; De Cecco, S; De Deo, M; De Vincenzi, M; Derbin, A; Devoto, 25 A; Di Eusanio, F; Di Pietro, G; Edkins, E; Empl, A; Fan, A; Fiorillo, G; Fomenko, K; Forster, G; Franco, D; Gabriele, F; Galbiati, C; Giganti, C; Goretti, A M; Granato, F; Grandi, L; Gromov, M; Guan, M; Guardincerri, Y; Hackett, B R; Herner, K; Hungerford, E V; Ianni, Al; Ianni, An; James, I; Jollet, C; Keeter, K; Kendziora, C L; Kobychev, V; Koh, G; Korablev, D; Korga, G; Kubankin, A; Li, X; Lissia, M; Lombardi, P; Luitz, S; Ma, Y; Machulin, I N; Mandarano, A; Mari, S M; Maricic, J; Marini, L; Martoff, C J; Meregaglia, A; Meyers, P D; Miletic, T; Milincic, R; Montanari, D; Monte, A; Montuschi, M; Monzani, M; Mosteiro, P; Mount, B J; Muratova, V N; Musico, P; Napolitano, J; Nelson, A; Odrowski, S; Orsini, M; Ortica, F; Pagani, L; Pallavicini, M; Pantic, E; Parmeggiano, S; Pelczar, K; Pelliccia, N; Perasso, S; Pocar, A; Pordes, S; Pugachev, D A; Qian, H; Randle, K; Ranucci, G; Razeto, A; Reinhold, B; Renshaw, A L; Romani, A; Rossi, B; Rossi, N; Rountree, D; Sablone, D; Saggese, P; Saldanha, R; Sands, W; Sangiorgio, S; Savarese, C; Segreto, E; Semenov, D A; Shields, E; Singh, P N; Skorokhvatov, M D; Smallcomb, M; Smirnov, O; Sotnikov, A; Stanford, C; Suvorov, Y; Tartaglia, R; Tatarowicz, J; Testera, G; Tonazzo, A; Trinchese, P; Unzhakov, E V; Vishneva, A; Vogelaar, B; Wada, M; Walker, S; Wang, H; Wang, Y; Watson, A W; Westerdale, S; Wilhelmi, J; Wojcik, M M; Xiang, X; Xu, J; Yang, C; Yoo, J; Zavatarelli, S; Zec, A; Zhong, W; Zhu, C; Zuzel, G

    2015-01-01

    The DarkSide-50 dark matter search reports the first results obtained using a target of low-radioactivity argon extracted from underground sources. The experiment is located at the Laboratori Nazionali del Gran Sasso and uses a two-phase time projection chamber as a detector. A total of 155 kg of low radioactivity argon has been obtained, and we have determined that underground argon is depleted in Ar-39 by a factor (1.4 +- 0.2) x 10^3 relative to atmospheric argon. The underground argon was also found to contain (2.05 +- 0.13) mBq/kg of Kr-85. We found no evidence for dark matter in the form of WIMPs in 70.9 live-days of data with a fiducial mass of (36.9 +- 0.6) kg. When combined with our preceding search with an atmospheric argon target, we set a 90 % C.L. upper limit on the WIMP-nucleon spin-independent cross section of 2.0 x 10^-44 cm^2 (8.6 x 10^-44 cm^2, 8.0 x 10^-43 cm^2 ) for a WIMP mass of 100 GeV/c^2 (1 TeV/c^2 , 10 TeV/c^2 ).

  14. Search for $B^{+}\\rightarrow K^{+} \\tau^{+}\\tau^{-}$ at the BaBar experiment

    CERN Document Server

    ,

    2016-01-01

    We search for the rare flavor-changing neutral current process $B^{+}\\rightarrow K^{+}\\tau^{+}\\tau^{-}$ using data from the BABAR experiment. The data sample, collected at the center-of-mass energy of the $\\Upsilon{(4S)}$ resonance, corresponds to a total integrated luminosity of 424 fb$^{-1}$ and to 471 million $B\\overline{B}$ pairs. We reconstruct one $B$ meson, produced in the $\\Upsilon{(4S)}\\rightarrow B^{+} B^{-}$ decay, in one of many hadronic decay modes and search for activity compatible with a $B^{+}\\rightarrow K^{+} \\tau^{+}\\tau^{-}$ decay in the rest of the event. Each $\\tau$ lepton is required to decay leptonically into an electron or muon and neutrinos. Comparing the expected number of background events with the data sample after applying the selection criteria, we do not find evidence for a signal. The measured branching fraction is ($1.31^{+0.66}_{-0.61}$( stat.)$^{+0.35}_{-0.25}$( sys.)$) \\times 10^{-3}$ with an upper limit, at the 90\\% confidence level, of $\\mathcal{B}(B^{+}\\rightarrow K^{+}\\...

  15. Search for muon antineutrino disappearance due to sterile antineutrino oscillations with the MINOS experiment

    Science.gov (United States)

    Chen, R.; Todd, J.; Poonthottathil, N.; Sousa, A.; Evans, J.; MINOS/MINOS+ Collaboration

    2017-09-01

    Three-flavour neutrino mixing has successfully explained a wide range of neutrino oscillation data. However, results such as the electron antineutrino appearance excesses seen by LSND and MiniBooNE can be explained in terms of neutrino oscillations adding a sterile neutrino at a larger mass scale than the existing three flavour mass states. MINOS is a two-detector, long-baseline neutrino oscillation experiment that uses magnetized tracker-calorimeter detectors to measure the energy and composition of the NuMI neutrino beam. These magnetized detectors give MINOS a unique ability to be able to separate muon neutrino and antineutrino interactions. Using data taken with the NuMI beam configured in antineutrino mode, MINOS is able to search for sterile antineutrinos by looking for the disappearance of muon antineutrinos over its 734 km baseline. The sterile antineutrino signature would be seen as modulations at high energy in the charged-current muon antineutrino spectrum. We present the first MINOS results constraining 3+1 sterile antineutrino oscillations, using a combination of 3.36×1020 protons-on-target (POT) of antineutrino-enhanced beam data, and 10.56×1020 protons-on-target (POT) of neutrino-dominated beam data. These results are compared with existing constraints and future improvements to the searches are discussed.

  16. Search for B+→K+τ+τ- at the BaBar Experiment

    Science.gov (United States)

    Lees, J. P.; Poireau, V.; Tisserand, V.; Grauges, E.; Palano, A.; Eigen, G.; Brown, D. N.; Kolomensky, Yu. G.; Koch, H.; Schroeder, T.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; So, R. Y.; Blinov, V. E.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Kravchenko, E. A.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu.; Lankford, A. J.; Gary, J. W.; Long, O.; Eisner, A. M.; Lockman, W. S.; Panduro Vazquez, W.; Chao, D. S.; Cheng, C. H.; Echenard, B.; Flood, K. T.; Hitlin, D. G.; Kim, J.; Miyashita, T. S.; Ongmongkolkul, P.; Porter, F. C.; Röhrken, M.; Huard, Z.; Meadows, B. T.; Pushpawela, B. G.; Sokoloff, M. D.; Sun, L.; Smith, J. G.; Wagner, S. R.; Bernard, D.; Verderi, M.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cibinetto, G.; Fioravanti, E.; Garzia, I.; Luppi, E.; Santoro, V.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Martellotti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Zallo, A.; Passaggio, S.; Patrignani, C.; Bhuyan, B.; Mallik, U.; Chen, C.; Cochran, J.; Prell, S.; Ahmed, H.; Gritsan, A. V.; Arnaud, N.; Davier, M.; Le Diberder, F.; Lutz, A. M.; Wormser, G.; Lange, D. J.; Wright, D. M.; Coleman, J. P.; Gabathuler, E.; Hutchcroft, D. E.; Payne, D. J.; Touramanis, C.; Bevan, A. J.; Di Lodovico, F.; Sacco, R.; Cowan, G.; Banerjee, Sw.; Brown, D. N.; Davis, C. L.; Denig, A. G.; Fritsch, M.; Gradl, W.; Griessinger, K.; Hafner, A.; Schubert, K. R.; Barlow, R. J.; Lafferty, G. D.; Cenci, R.; Jawahery, A.; Roberts, D. A.; Cowan, R.; Cheaib, R.; Robertson, S. H.; Dey, B.; Neri, N.; Palombo, F.; Cremaldi, L.; Godang, R.; Summers, D. J.; Taras, P.; De Nardo, G.; Sciacca, C.; Raven, G.; Jessop, C. P.; LoSecco, J. M.; Honscheid, K.; Kass, R.; Gaz, A.; Margoni, M.; Posocco, M.; Rotondo, M.; Simi, G.; Simonetto, F.; Stroili, R.; Akar, S.; Ben-Haim, E.; Bomben, M.; Bonneaud, G. R.; Calderini, G.; Chauveau, J.; Marchiori, G.; Ocariz, J.; Biasini, M.; Manoni, E.; Rossi, A.; Batignani, G.; Bettarini, S.; Carpinelli, M.; Casarosa, G.; Chrzaszcz, M.; Forti, F.; Giorgi, M. A.; Lusiani, A.; Oberhof, B.; Paoloni, E.; Rama, M.; Rizzo, G.; Walsh, J. J.; Smith, A. J. S.; Anulli, F.; Faccini, R.; Ferrarotto, F.; Ferroni, F.; Pilloni, A.; Piredda, G.; Bünger, C.; Dittrich, S.; Grünberg, O.; Heß, M.; Leddig, T.; Voß, C.; Waldi, R.; Adye, T.; Wilson, F. F.; Emery, S.; Vasseur, G.; Aston, D.; Cartaro, C.; Convery, M. R.; Dorfan, J.; Dunwoodie, W.; Ebert, M.; Field, R. C.; Fulsom, B. G.; Graham, M. T.; Hast, C.; Innes, W. R.; Kim, P.; Leith, D. W. G. S.; Luitz, S.; Luth, V.; MacFarlane, D. B.; Muller, D. R.; Neal, H.; Ratcliff, B. N.; Roodman, A.; Sullivan, M. K.; Va'vra, J.; Wisniewski, W. J.; Purohit, M. V.; Wilson, J. R.; Randle-Conde, A.; Sekula, S. J.; Bellis, M.; Burchat, P. R.; Puccio, E. M. T.; Alam, M. S.; Ernst, J. A.; Gorodeisky, R.; Guttman, N.; Peimer, D. R.; Soffer, A.; Spanier, S. M.; Ritchie, J. L.; Schwitters, R. F.; Izen, J. M.; Lou, X. C.; Bianchi, F.; De Mori, F.; Filippi, A.; Gamba, D.; Lanceri, L.; Vitale, L.; Martinez-Vidal, F.; Oyanguren, A.; Albert, J.; Beaulieu, A.; Bernlochner, F. U.; King, G. J.; Kowalewski, R.; Lueck, T.; Nugent, I. M.; Roney, J. M.; Tasneem, N.; Gershon, T. J.; Harrison, P. F.; Latham, T. E.; Prepost, R.; Wu, S. L.; BaBar Collaboration

    2017-01-01

    We search for the rare flavor-changing neutral current process B+→K+τ+τ- using data from the BABAR experiment. The data sample, collected at the center-of-mass energy of the ϒ (4 S ) resonance, corresponds to a total integrated luminosity of 424 fb-1 and to 471 ×1 06 B B ¯ pairs. We reconstruct one B meson, produced in the ϒ (4 S )→B+B- decay, in one of many hadronic decay modes and search for activity compatible with a B+→K+τ+τ- decay in the rest of the event. Each τ lepton is required to decay leptonically into an electron or muon and neutrinos. Comparing the expected number of background events with the data sample after applying the selection criteria, we do not find evidence for a signal. The resulting upper limit, at the 90% confidence level, is B (B+→K+τ+τ-)<2.25 ×10-3 .

  17. Search for B^{+}→K^{+}τ^{+}τ^{-} at the BaBar Experiment.

    Science.gov (United States)

    Lees, J P; Poireau, V; Tisserand, V; Grauges, E; Palano, A; Eigen, G; Brown, D N; Kolomensky, Yu G; Koch, H; Schroeder, T; Hearty, C; Mattison, T S; McKenna, J A; So, R Y; Blinov, V E; Buzykaev, A R; Druzhinin, V P; Golubev, V B; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Todyshev, K Yu; Lankford, A J; Gary, J W; Long, O; Eisner, A M; Lockman, W S; Panduro Vazquez, W; Chao, D S; Cheng, C H; Echenard, B; Flood, K T; Hitlin, D G; Kim, J; Miyashita, T S; Ongmongkolkul, P; Porter, F C; Röhrken, M; Huard, Z; Meadows, B T; Pushpawela, B G; Sokoloff, M D; Sun, L; Smith, J G; Wagner, S R; Bernard, D; Verderi, M; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Fioravanti, E; Garzia, I; Luppi, E; Santoro, V; Calcaterra, A; de Sangro, R; Finocchiaro, G; Martellotti, S; Patteri, P; Peruzzi, I M; Piccolo, M; Zallo, A; Passaggio, S; Patrignani, C; Bhuyan, B; Mallik, U; Chen, C; Cochran, J; Prell, S; Ahmed, H; Gritsan, A V; Arnaud, N; Davier, M; Le Diberder, F; Lutz, A M; Wormser, G; Lange, D J; Wright, D M; Coleman, J P; Gabathuler, E; Hutchcroft, D E; Payne, D J; Touramanis, C; Bevan, A J; Di Lodovico, F; Sacco, R; Cowan, G; Banerjee, Sw; Brown, D N; Davis, C L; Denig, A G; Fritsch, M; Gradl, W; Griessinger, K; Hafner, A; Schubert, K R; Barlow, R J; Lafferty, G D; Cenci, R; Jawahery, A; Roberts, D A; Cowan, R; Cheaib, R; Robertson, S H; Dey, B; Neri, N; Palombo, F; Cremaldi, L; Godang, R; Summers, D J; Taras, P; De Nardo, G; Sciacca, C; Raven, G; Jessop, C P; LoSecco, J M; Honscheid, K; Kass, R; Gaz, A; Margoni, M; Posocco, M; Rotondo, M; Simi, G; Simonetto, F; Stroili, R; Akar, S; Ben-Haim, E; Bomben, M; Bonneaud, G R; Calderini, G; Chauveau, J; Marchiori, G; Ocariz, J; Biasini, M; Manoni, E; Rossi, A; Batignani, G; Bettarini, S; Carpinelli, M; Casarosa, G; Chrzaszcz, M; Forti, F; Giorgi, M A; Lusiani, A; Oberhof, B; Paoloni, E; Rama, M; Rizzo, G; Walsh, J J; Smith, A J S; Anulli, F; Faccini, R; Ferrarotto, F; Ferroni, F; Pilloni, A; Piredda, G; Bünger, C; Dittrich, S; Grünberg, O; Heß, M; Leddig, T; Voß, C; Waldi, R; Adye, T; Wilson, F F; Emery, S; Vasseur, G; Aston, D; Cartaro, C; Convery, M R; Dorfan, J; Dunwoodie, W; Ebert, M; Field, R C; Fulsom, B G; Graham, M T; Hast, C; Innes, W R; Kim, P; Leith, D W G S; Luitz, S; Luth, V; MacFarlane, D B; Muller, D R; Neal, H; Ratcliff, B N; Roodman, A; Sullivan, M K; Va'vra, J; Wisniewski, W J; Purohit, M V; Wilson, J R; Randle-Conde, A; Sekula, S J; Bellis, M; Burchat, P R; Puccio, E M T; Alam, M S; Ernst, J A; Gorodeisky, R; Guttman, N; Peimer, D R; Soffer, A; Spanier, S M; Ritchie, J L; Schwitters, R F; Izen, J M; Lou, X C; Bianchi, F; De Mori, F; Filippi, A; Gamba, D; Lanceri, L; Vitale, L; Martinez-Vidal, F; Oyanguren, A; Albert, J; Beaulieu, A; Bernlochner, F U; King, G J; Kowalewski, R; Lueck, T; Nugent, I M; Roney, J M; Tasneem, N; Gershon, T J; Harrison, P F; Latham, T E; Prepost, R; Wu, S L

    2017-01-20

    We search for the rare flavor-changing neutral current process B^{+}→K^{+}τ^{+}τ^{-} using data from the BABAR experiment. The data sample, collected at the center-of-mass energy of the ϒ(4S) resonance, corresponds to a total integrated luminosity of 424  fb^{-1} and to 471×10^{6}  BB[over ¯] pairs. We reconstruct one B meson, produced in the ϒ(4S)→B^{+}B^{-} decay, in one of many hadronic decay modes and search for activity compatible with a B^{+}→K^{+}τ^{+}τ^{-} decay in the rest of the event. Each τ lepton is required to decay leptonically into an electron or muon and neutrinos. Comparing the expected number of background events with the data sample after applying the selection criteria, we do not find evidence for a signal. The resulting upper limit, at the 90% confidence level, is B(B^{+}→K^{+}τ^{+}τ^{-})<2.25×10^{-3}.

  18. How do radiologists do it? The influence of experience and training on searching for chest nodules

    Energy Technology Data Exchange (ETDEWEB)

    Manning, David [Department of Medical Imaging Sciences, St Martin' s College, Lancaster LA1 3JD (United Kingdom)]. E-mail: d.manning@ucsm.ac.uk; Ethell, Susan [Department of Medical Imaging Sciences, St Martin' s College, Lancaster LA1 3JD (United Kingdom); Donovan, Tim [Department of Medical Imaging Sciences, St Martin' s College, Lancaster LA1 3JD (United Kingdom); Crawford, Trevor [Department of Psychology, Lancaster University, Lancaster (United Kingdom)

    2006-05-15

    Four observer groups with different levels of expertise were tested to investigate the nature of expert performance. The task was the detection and localisation of significant pulmonary nodules in postero-anterior views of the chest. One hundred and twenty digitised chest images were used. The observer groups were 8 experienced radiologists, 5 experienced radiographers before and after six months training in chest image interpretation, and 8 undergraduate radiography students. Eye tracking was carried out to investigate differences in visual search strategies between observers. Detection performance was measured with an Alternate Free Response Operating Characteristic technique. Performance measures showed the experienced group of radiologists plus radiographers after training were better at the task than the remainder (t-test p = 0.046). Differences were shown in the eye-tracking parameters between the groups: saccadic amplitude (ANOVA p 0.00047), number of fixations before and after training (t-test p = 0.041), and scrutiny time per decision and per film for the experienced versus the inexperienced observers (t-test p = 0.02). Visual coverage reduced with increasing level of experience but this result did not reach significance. Generally there were distinct differences in the search strategies between the experienced and inexperienced observers and we discuss the significance of these findings. We believe the results support some recent theoretical models of expert performance and that the findings may prove to be helpful in 'fast-track' educational programmes of image interpretation for non-radiology practitioners.

  19. Search for chameleon scalar fields with the axion dark matter experiment.

    Science.gov (United States)

    Rybka, G; Hotz, M; Rosenberg, L J; Asztalos, S J; Carosi, G; Hagmann, C; Kinion, D; van Bibber, K; Hoskins, J; Martin, C; Sikivie, P; Tanner, D B; Bradley, R; Clarke, J

    2010-07-30

    Scalar fields with a "chameleon" property, in which the effective particle mass is a function of its local environment, are common to many theories beyond the standard model and could be responsible for dark energy. If these fields couple weakly to the photon, they could be detectable through the afterglow effect of photon-chameleon-photon transitions. The ADMX experiment was used in the first chameleon search with a microwave cavity to set a new limit on scalar chameleon-photon coupling βγ excluding values between 2×10(9) and 5×10(14) for effective chameleon masses between 1.9510 and 1.9525  μeV.

  20. Magnetic monopole searches with the MoEDAL experiment at the LHC

    CERN Document Server

    Pinfold, J; Lacarrère, D; Mermod, P; Katre, A

    2014-01-01

    The magnetic monopole appears in theories of spontaneous ga uge symmetry breaking and its existence would explain the quantisation of electric charg e. MoEDAL is the latest approved LHC experiment, designed to search directly for monopoles. It h as now taken data for the first time. The MoEDAL detectors are based on two complementary techniq ues: nuclear-track detectors are sensitive to the high-ionisation signature expected fr om a monopole, and the new magnetic monopole trapper (MMT) relies on the stopping and trapping o f monopoles inside an aluminium array which is then analysed with a superconducting magneto meter. Preliminary results obtained with a subset of the MoEDAL MMT test array deployed in 2012 are presented, where monopoles with charge above the fundamental unit magnetic charge or ma ss above 1.5 TeV are probed for the first time at the LHC

  1. First dark matter search results from the PandaX-I experiment

    Science.gov (United States)

    Xiao, MengJiao; Xiao, Xiang; Zhao, Li; Cao, XiGuang; Chen, Xun; Chen, YunHua; Cui, XiangYi; Fang, DeQing; Fu, ChangBo; Giboni, Karl L.; Gong, HaoWei; Guo, GuoDong; Hu, Jie; Huang, XingTao; Ji, XiangDong; Ju, YongLin; Lei, SiAo; Li, ShaoLi; Lin, Qing; Liu, HuaXuan; Liu, JiangLai; Liu, Xiang; Lorenzon, Wolfgang; Ma, YuGang; Mao, YaJun; Ni, KaiXuan; Pushkin, Kirill; Ren, XiangXiang; Schubnell, Michael; Shen, ManBing; Stephenson, Scott; Tan, AnDi; Tarlé, Greg; Wang, HongWei; Wang, JiMin; Wang, Meng; Wang, XuMing; Wang, Zhou; Wei, YueHuan; Wu, ShiYong; Xie, PengWei; You, YingHui; Zeng, XiongHui; Zhang, Hua; Zhang, Tao; Zhu, ZhongHua

    2014-11-01

    We report on the first dark-matter (DM) search results from PandaX-I, a low threshold dual-phase xenon experiment operating at the China JinPing Underground Laboratory. In the 37-kg liquid xenon target with 17.4 live-days of exposure, no DM particle candidate event was found. This result sets a stringent limit for low-mass DM particles and disfavors the interpretation of previously-reported positive experimental results. The minimum upper limit, 3.7 × 10-44 cm2, for the spin-independent isoscalar DM-particle-nucleon scattering cross section is obtained at a DM-particle mass of 49GeV/c2 at 90% confidence level.

  2. First dark matter search results from the PandaX-I experiment

    CERN Document Server

    Xiao, Mengjiao; Zhao, Li; Cao, Xiguang; Chen, Xun; Chen, Yunhua; Cui, Xiangyi; Fang, Deqing; Fu, Changbo; Giboni, Karl L; Gong, Haowei; Guo, Guodong; Hu, Jie; Huang, Xingtao; Ji, Xiangdong; Ju, Yonglin; Lei, Siao; Li, Shaoli; Lin, Qing; Liu, Huaxuan; Liu, Jianglai; Liu, Xiang; Lorenzon, Wolfgang; Ma, Yugang; Mao, Yajun; Ni, Kaixuan; Pushkin, Kirill; Ren, Xiangxiang; Schubnell, Michael; Shen, Manbing; Stephenson, Scott; Tan, Andi; Tarle, Greg; Wang, Hongwei; Wang, Jimin; Wang, Meng; Wang, Xuming; Wang, Zhou; Wei, Yuehuan; Wu, Shiyong; Xie, Pengwei; You, Yinghui; Zeng, Xionghui; Zhang, Hua; Zhang, Tao; Zhu, Zhonghua

    2014-01-01

    We report on the first dark-matter (DM) search results from PandaX-I, a low threshold dual-phase xenon experiment operating at the China Jinping Underground Laboratory. In the 37-kg liquid xenon target with 17.4 live-days of exposure, no DM particle candidate event was found. This result sets a stringent limit for low-mass DM particles and disfavors the interpretation of previously-reported positive experimental results. The minimum upper limit, $3.7\\times10^{-44}$\\,cm$^2$, for the spin-independent isoscalar DM-particle-nucleon scattering cross section is obtained at a DM-particle mass of 49\\,GeV/c$^2$ at 90\\% confidence level.

  3. Search for the Higgs-Boson with the CDF experiment at Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Hennecke, Martin [Univ. of Karlsruhe (Germany)

    2005-06-10

    A search for a low-mass SM Higgs-Boson in the channel WH → lvb$\\bar{b}$ has been performed using neural networks. The data were taken by the CDF experiment at the p-$\\bar{p}$ collider Tevatron from 2000-2003, corresponding to in integrated luminosity of Lint = 162 pb-1 at a CMS-energy of √s = 1.96 TeV. 95% confidence level upper limits are set on σ × BR, the product of the production cross section times the Branching ratio, as a function of the Higgs boson mass. Cross sections above 8 pb are excluded for six different Higgs masses between 110 GeV/c2 and 150 GeV/c2. The required integrated luminosities for a 95% C.L. exclusion, 3σ evidence and 5σ discovery are calculated.

  4. First dark matter search results from the PandaX-I experiment

    Institute of Scientific and Technical Information of China (English)

    XIAO MengJiao; XIAO Xiang; ZHAO Li; CAO XiGuang; CHEN Xun; CHEN YunHua; CUI XiangYi

    2014-01-01

    We report on the first dark-matter (DM) search results from PandaX-Ⅰ,a low threshold dual-phase xenon experiment operating at the China JinPing Underground Laboratory.In the 37-kg liquid xenon target with 17.4 live-days of exposure,no DM particle candidate event was found.This result sets a stringent limit for low-mass DM particles and disfavors the interpretation of previously-reported positive experimental results.The minimum upper limit,3.7 × 10-44 cm2,for the spin-independent isoscalar DM-particle-nucleon scattering cross section is obtained at a DM-particle mass of 49 GeV/c2 at 90% confidence level.

  5. The WArP Experiment: A Double-Phase Argon Detector for Dark Matter Searches

    Directory of Open Access Journals (Sweden)

    Andrea Zani

    2014-01-01

    Full Text Available Cryogenic noble liquids emerged in the previous decade as one of the best media to perform WIMP dark matter searches, in particular due to the possibility to scale detector volumes to multiton sizes. The WArP experiment was then developed as one of the first to implement the idea of coupling Argon in liquid and gas phase, in order to discriminate β/γ-interactions from nuclear recoils and then achieve reliable background rejection. Since its construction, other projects spawned, employing Argon and Xenon and following its steps. The WArP 100l detector was assembled in 2008 at the Gran Sasso National Laboratories (LNGS, as the final step of a years-long R&D programme, aimed at characterising the technology of Argon in double phase for dark matter detection. Though it never actually performed a physics run, a technical run was taken in 2011, to characterise the detector response.

  6. The NAIAD experiment for WIMP searches at Boulby mine and recent results

    CERN Document Server

    Ahmed, B; Araújo, H M; Barton, J C; Bewick, A; Carson, M J; Davidge, D; Dawson, J V; Gamble, T; Hart, S P; Hollingworth, R J; Howard, A S; Jones, W G; Joshi, M K; Kudryavtsev, V A; Lawson, T B; Lebedenko, V; Lehner, M J; Lewin, J D; Lightfoot, P K; Liubarsky, I; Lüscher, R; McMillan, J E; Morgan, B; Nicklin, G; Paling, S M; Preece, R M; Quenby, J J; Roberts, J W; Robinson, M; Smith, N J T; Smith, P F; Spooner, N J C; Sumner, T J; Tovey, Daniel R

    2003-01-01

    The NAIAD experiment (NaI Advanced Detector) for WIMP dark matter searches at Boulby mine (UK) is described. The detector consists of an array of encapsulated and unencapsulated NaI(Tl) crystals with high light yield. Six crystals are collecting data at present. Data accumulated by four of them (10.6 kg x year exposure) have been used to set upper limits on the WIMP-nucleon spin-independent and WIMP-proton spin-dependent cross-sections. Pulse shape analysis has been applied to discriminate between nuclear recoils, as may be caused by WIMP interactions, and electron recoils due to gamma background. Various calibrations of crystals are presented.

  7. First Results from Dark Matter Search Experiment in the Nokogiriyama Underground Cell

    CERN Document Server

    Ootani, W; Miuchi, K; Inoue, Y; Watanabe, T; Yoshida, M; Ito, Y; Ootuka, Y

    1999-01-01

    An experiment to search for hypothetical particle dark matter using cryogenic thermal detector, or bolometer is ongoing. The bolometer consists of eight pieces of 21 g LiF absorbers and sensitive NTD germanium thermistors attached to them and is installed in the Nokogiriyama underground cell which is a shallow depth site ($\\sim 15$ m w.e.). We report on the results from the first running for about ten days using this arrayed bolometer system together with appropriate shieldings and muon veto counters. From the obtained energy spectra the exclusion limits for the cross section of the elastic neutralino-proton scattering are derived under commonly accepted astrophysical assumptions. The sensitivity for the light neutralino with a mass below 5 GeV is improved by this work.

  8. Improving the quality factor of microwave cavities for axion search experiments

    Science.gov (United States)

    Ahn, Saebyeok; Jung, Junu; Youn, Sungwoo; Semertzidis, Yannis

    2017-01-01

    In cavity-based axion search experiments, the quality factor (Q) of microwave resonant cavities is an important parameter to be sensitive to faint signal from the axion-to-photon conversion. One of the R&D efforts conducted at the Center for Axion and Precision Physics Research (CAPP) of the Institute for Basic Science (IBS) is to improve the quality factor of resonant cavities by employing two approaches - pure material and heat treatment. Using a 4K cryocooler and liquid helium, we measure the temperature dependence of Q value to find the effect of material purity and an optimal condition of heat treatment. The measurements are performed on Cu and Al cavities and the results are shown in this presentation.

  9. Search for supersymmetry in the hadronic channel with data from the CMS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Thomsen, Jan

    2012-05-15

    The CMS experiment at the LHC has taken data from proton-proton collisions at the center of mass energy of 7 TeV. This data is used to search for new physics with an analysis based on large missing transvere energy and high energetic jets. The Standard Model background is estimated with high precision using data-driven estimation methods. The prediction of the background from t anti t and W+jet events with non-identified electrons and muons from the W-decay is discussed in detail in this analysis. No excess over the Standard Model expectation could be found in the data. The results are interpreted with the CL{sub S}-method within the constraint minimal supersymmetric Standard Model (cMSSM). A lower limit on the squark mass of 1100 GeV can be set.

  10. Search for narrow pion-proton states in s-channel at EPECUR: experiment status

    CERN Document Server

    Alekseev, I G; Bordyuzhin, I G; Budkovsky, P Ye; Fedin, D A; Filimonov, Ye A; Golubev, V V; Kanavets, V P; Koroleva, L I; Kovalev, A I; Kozlenko, N G; Kozlov, V S; Krivshich, A G; Morozov, B V; Nesterov, V M; Novinsky, D V; Ryltsov, V V; Sadler, M; Sulimov, A D; Sumachev, V V; Svirida, D N; Tarakanov, V I; Trautman, V Yu

    2009-01-01

    An experiment EPECUR, aimed at the search of the cryptoexotic non-strange member of the pentaquark antidecuplet, started its operation at a pion beam line of the ITEP 10 GeV proton synchrotron. The invariant mass range of the interest (1610-1770) MeV will be scanned for a narrow state in the pion-proton and kaon-lambda systems in the formation-type experiment. The scan in the s-channel is supposed to be done by the variation of the incident pi- momentum and its measurement with the accuracy of up to 0.1% with a set of 1 mm pitch proportional chambers located in the first focus of the beam line. The reactions under the study will be identified by a magnetless spectrometer based on wire drift chambers with a hexagonal structure. Because the background suppression in this experiment depends on the angular resolution, the amount of matter in the chambers and setup is minimized to reduce multiple scattering. The differential cross section of the elastic pi-p-scattering on a liquid hydrogen target in the region of ...

  11. [Searching for rest in one's soul: the experience of mental health complaints in older Moroccan immigrants].

    Science.gov (United States)

    de Vries, W M; Smits, C H M

    2005-11-01

    The number of Moroccan elderly in the Netherlands is growing. Although many have mental health problems, the mental health services have difficulties in reaching them. This study reports on the experience of mental health problems of elderly Moroccan migrants, their search for help and their view on the role of the mental health services. Twenty-two Moroccan elderly (11 men, 11 women) aged 55-75 were interviewed with a semi-structured questionnaire. From the interviews and observations it appeared that these elderly experience their health as bad. When asked, they deny mental health problems. Stress and dejection are not experienced as relating to mental health but as part of life associated with ageing, living in a foreign country, having physical, social and financial problems. The elderly feel that God sets them these tasks to overcome by themselves. Achieving rest in one's soul is central in this process. There is a taboo on serious mental health problems and people are ashamed of them. Only people who neglect religious prescriptions can to be affected by mental health problems. The elderly Moroccans hardly consult mental health services for these problems because then it would become clear that they cannot overcome their problems by themselves. Furthermore, the mental health services are unknown. Therefore, those services have to pay attention to the specific experience of mental complaints of elderly Moroccans. By offering psycho-education the mental health services may come within reach of those elderly.

  12. The Experience of Emotions during the Job Search and Choice Process among Novice Job Seekers

    Science.gov (United States)

    Bonaccio, Silvia; Gauvin, Natalie; Reeve, Charlie L.

    2014-01-01

    The authors investigate the role of emotions in the job search and choice process of novice job seekers. Results of qualitative analyses of the first-person accounts of 41 job seekers indicate that participants whose recollections of their job search contained emotional language were more likely to display a haphazard job search strategy than…

  13. The Experience of Emotions during the Job Search and Choice Process among Novice Job Seekers

    Science.gov (United States)

    Bonaccio, Silvia; Gauvin, Natalie; Reeve, Charlie L.

    2014-01-01

    The authors investigate the role of emotions in the job search and choice process of novice job seekers. Results of qualitative analyses of the first-person accounts of 41 job seekers indicate that participants whose recollections of their job search contained emotional language were more likely to display a haphazard job search strategy than…

  14. HyperCP (E871) experiment at Fermilab: search for direct CP violation in hyperon decays

    Energy Technology Data Exchange (ETDEWEB)

    Leros, N.; Burnstein, R.A.; Chakravorty, A.; Chan, A.; Chen, Y.C.; Choong, W.S.; Clark, K.; Dukes, E.C.; Durandet, C.; Felix, J.; Gidal, G.; Gustafson, H.R.; Ho, C.; Holmstrom, T.; Huang, M.; James, C.; Jenkins, M.; Jones, T.; Kaplan, D.M.; Lederman, L.M.; Longo, M.J.; Lopez, F.; Lu, L.C.; Luebke, W.; Luk, K.B.; Moreno, G.; Nelson, K.S.; Park, H.K.; Perroud, J.P.; Rajaram, D.; Rubin, H.A.; Sosa, M.; Teng, P.K.; Turko, B.; Volk, J.; White, C.; White, S.L.; Zyla, P

    2001-05-01

    The Fermilab HyperCP experiment has accumulated the world's largest sample of {xi}{sup -} and {xi}-bar{sup +} hyperon decays within two running periods in 1997 and 1999. The primary goal of the experiment is to search for direct CP violation in the decay sequences {xi}{sup -} {yields} {lambda} {pi}{sup -} {yields} p {pi}{sup -} {pi}{sup -} and {xi}-bar{sup +} {yields} {lambda}-bar {pi}{sup +} {yields} p-bar {pi}{sup +} {pi}{sup +}. A violation of CP would manifest itself as a difference between the angular distribution of the proton and the antiproton in the {lambda} and {lambda}-bar helicity frame. The amount of data is enough to reach a statistical sensitivity of 1.4 x 10{sup -4} in the CP violating asymmetry A{sub {xi}}{sub {lambda}} = ({alpha}{sub {xi}} {alpha}{sub {lambda}} - {alpha}{sub {xi}}{sub -bar} {alpha}{sub {lambda}}{sub -bar})/({alpha}{sub {xi}} {alpha}{sub {lambda}} + {alpha}{sub {xi}}{sub -bar} {alpha}{sub {lambda}}{sub -bar}). We present an analysis method used to take into account the slight differences in the production of the {xi}{sup -} and {xi}-bar{sup +} samples. A preliminary results on A{sub {xi}}{sub {lambda}} at the level of a few 10{sup -3} and based on a few percent of the 1997 data will be presented.

  15. Search for Supersymmetry in Opposite-sign Dilepton Final States with the CMS Experiment

    CERN Document Server

    Sprenger, Daniel

    2012-01-01

    For centuries, men’s curiosity drove him to explore the secrets of nature and the essentialprinciples and constituents of matter. Today, the Standard Model of particle physicssuccessfully describes a significant part of the known universe and most experimentalobservations. Still several experimental and theoretical findings indicate that the StandardModel is only valid up to an energy scale of a few TeV.The Large Hadron Collider is, together with its detector experiments, the largest and mostsophisticated experiment ever constructed and conducted in the history of mankind. It isdesigned to collide protons at a centre-of-mass energy of up to 14 TeV, and its purpose isto test the current Standard Model of particle physics and search for physics beyond thismodel. One promising new-physics theory is Supersymmetry, which extends the StandardModel by supersymmetric partner particles for the particles in the Standard Model.This work uses proton-proton collision data at a centre-of-mass energy of 7 TeV taken byth...

  16. The MoEDAL experiment at the LHC. Searching beyond the standard model

    Science.gov (United States)

    Pinfold, James L.

    2016-11-01

    MoEDAL is a pioneering experiment designed to search for highly ionizing avatars of new physics such as magnetic monopoles or massive (pseudo-)stable charged particles. Its groundbreaking physics program defines a number of scenarios that yield potentially revolutionary insights into such foundational questions as: are there extra dimensions or new symmetries; what is the mechanism for the generation of mass; does magnetic charge exist; what is the nature of dark matter; and, how did the big-bang develop. MoEDAL's purpose is to meet such far-reaching challenges at the frontier of the field. The innovative MoEDAL detector employs unconventional methodologies tuned to the prospect of discovery physics. The largely passive MoEDAL detector, deployed at Point 8 on the LHC ring, has a dual nature. First, it acts like a giant camera, comprised of nuclear track detectors - analyzed offline by ultra fast scanning microscopes - sensitive only to new physics. Second, it is uniquely able to trap the particle messengers of physics beyond the Standard Model for further study. MoEDAL's radiation environment is monitored by a state-of-the-art real-time TimePix pixel detector array. A new MoEDAL sub-detector to extend MoEDAL's reach to millicharged, minimally ionizing, particles (MMIPs) is under study Finally we shall describe the next step for MoEDAL called Cosmic MoEDAL, where we define a very large high altitude array to take the search for highly ionizing avatars of new physics to higher masses that are available from the cosmos.

  17. Search for MSSM Higgs bosons in Di-{tau} final states with the ATLAS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Anders, Christoph

    2013-02-15

    significant improvements over those obtained by similar searches of other experiments at LEP and the Tevatron.

  18. Liverpool Telescope follow-up of candidate electromagnetic counterparts during the first run of Advanced LIGO

    Science.gov (United States)

    Copperwheat, C. M.; Steele, I. A.; Piascik, A. S.; Bersier, D.; Bode, M. F.; Collins, C. A.; Darnley, M. J.; Galloway, D. K.; Gomboc, A.; Kobayashi, S.; Lamb, G. P.; Levan, A. J.; Mazzali, P. A.; Mundell, C. G.; Pian, E.; Pollacco, D.; Steeghs, D.; Tanvir, N. R.; Ulaczyk, K.; Wiersema, K.

    2016-11-01

    The first direct detection of gravitational waves was made in 2015 September with the Advanced LIGO detectors. By prior arrangement, a worldwide collaboration of electromagnetic follow-up observers were notified of candidate gravitational wave events during the first science run, and many facilities were engaged in the search for counterparts. Three alerts were issued to the electromagnetic collaboration over the course of the first science run, which lasted from 2015 September to 2016 January. Two of these alerts were associated with the gravitational wave events since named GW150914 and GW151226. In this paper we provide an overview of the Liverpool Telescope contribution to the follow-up campaign over this period. Given the hundreds of square degree uncertainty in the sky position of any gravitational wave event, efficient searching for candidate counterparts required survey telescopes with large (˜degrees) fields of view. The role of the Liverpool Telescope was to provide follow-up classification spectroscopy of any candidates. We followed candidates associated with all three alerts, observing 1, 9 and 17 candidates respectively. We classify the majority of the transients we observed as supernovae. No counterparts were identified, which is in line with expectations given that the events were classified as black hole-black hole mergers. However these searches laid the foundation for similar follow-up campaigns in future gravitational wave detector science runs, in which the detection of neutron star merger events with observable electromagnetic counterparts is much more likely.

  19. Background constrains of the SuperNEMO experiment for neutrinoless double beta-decay searches

    Science.gov (United States)

    Povinec, Pavel P.

    2017-02-01

    The SuperNEMO experiment is a new generation of experiments dedicated to the search for neutrinoless double beta-decay, which if observed, would confirm the existence of physics beyond the Standard Model. It is based on the tracking and calorimetry techniques, which allow the reconstruction of the final state topology, including timing and kinematics of the double beta-decay transition events, offering a powerful tool for background rejection. While the basic detection strategy of the SuperNEMO detector remains the same as of the NEMO-3 detector, a number of improvements were accomplished for each of detector main components. Upgrades of the detector technologies and development of low-level counting techniques ensure radiopurity control of construction parts of the SuperNEMO detector. A reference material made of glass pellets has been developed to assure quality management and quality control of radiopurity measurements. The first module of the SuperNEMO detector (Demonstrator) is currently under construction in the Modane underground laboratory. No background event is expected in the neutrinoless double beta-decay region in 2.5 years of its operation using 7 kg of 82Se. The half-life sensitivity of the Demonstrator is expected to be >6.5·1024 y, corresponding to an effective Majorana neutrino mass sensitivity of |0.2-0.4| eV (90% C.L.). The full SuperNEMO experiment comprising of 20 modules with 100 kg of 82Se source should reach an effective Majorana neutrino mass sensitivity of |0.04-0.1| eV, and a half-life limit 1·1026 y.

  20. Amino acid alphabet size in protein evolution experiments: better to search a small library thoroughly or a large library sparsely?

    Science.gov (United States)

    Muñoz, Enrique; Deem, Michael W

    2008-05-01

    We compare the results obtained from searching a smaller library thoroughly versus searching a more diverse, larger library sparsely. We study protein evolution with reduced amino acid alphabets, by simulating directed evolution experiments at three different alphabet sizes: 20, 5 and 2. We employ a physical model for evolution, the generalized NK model, that has proved successful in modeling protein evolution, antibody evolution and T-cell selection. We find that antibodies with higher affinity are found by searching a library with a larger alphabet sparsely than by searching a smaller library thoroughly, even with well-designed reduced libraries. We also find ranked amino acid usage frequencies in agreement with observations of the CDR-H3 variable region of human antibodies.

  1. Supersymmetric plasma systems and their nonsupersymmetric counterparts

    CERN Document Server

    Czajka, Alina

    2016-01-01

    In this thesis a systematic comparison of supersymmetric plasma systems and their nonsupersymmetric counterparts is presented. The work is motivated by the AdS/CFT correspondence and the main aim is to check how much the plasma governed by the N=4 super Yang-Mills theory resembles the quark-gluon plasma studied experimentally in relativistic heavy-ion collisions. The analysis is done in a weak coupling regime where perturbative methods are applicable. Since the Keldysh-Schwinger approach is used, not only equilibrium but also nonequilibrium plasmas, which are assumed to be ultrarelativistic, are under consideration. First, using the functional techniques we introduce Faddeev-Popov ghosts into the Keldysh-Schwinger formalism of nonAbelian gauge theories. Next the collective excitations of the N=1 SUSY QED plasma are considered and compared to those of the usual QED system. The analysis is repeated to confront with each other the plasmas governed by the N=4 super Yang-Mills and QCD theories. Finally, transport ...

  2. A Search for Associated Production of an SM Higgs Decaying into Tau Leptons with the Atlas Experiment

    DEFF Research Database (Denmark)

    Thomsen, Lotte Ansgaard

    Two distinct topics are covered in this thesis: tau hadronic decay identification and the search for a Standard Model (SM) Higgs boson in associated production with a W boson decaying into tau leptons within the ATLAS experiment. Prior to the work presented in this thesis, tau identification has...... analyses involving hadronic tau decays. The second part of this thesis covers the search for associated production of a SM Higgs boson decaying into tau leptons with the ATLAS experiment. The search procedure is made robust by developing a background estimation method relying on simulation...... production one should be able to reach sensitivity to SM production of Higgs in association to vector bosons in Run 1 data of LHC. This also provides proof that this channel is important for Higgs property measurements in Run 2 and beyond....

  3. Measurement of the dijet angular distributions and search for quark compositeness with the CMS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Hinzmann, Andreas Dominik

    2011-10-07

    {sub 2}} {sup vertical} {sup stroke}, where y{sub 1} and y{sub 2} are the rapidities of the two jets, y {identical_to} (1)/(2)ln [(E+p{sub z})/(E-p{sub z})], and p{sub z} is the projection of the jet momentum along the beam axis. The choice of the variable {chi}{sub dijet} is motivated by the fact that the normalized differential cross section (1)/({sigma}) (d{sigma})/(d{chi}{sub dijet}) (the dijet angular distribution) is flat in this variable for Rutherford scattering, characteristic for spin-1 particle exchange. In contrast to QCD which predicts a dijet angular distribution similar to Rutherford scattering, new physics, such as quark compositeness, that might have a more isotropic dijet angular distribution would produce an excess at low values of {chi}{sub dijet}. Since the shapes of the dijet angular distributions for the qg {yields}qg, qq{sup '} {yields}qq{sup '} and gg {yields}gg scattering processes are similar, the QCD prediction does not strongly depend on the parton distribution functions (PDFs) which describe the momentum distribution of the partons inside the protons. Due to the normalization, the dijet angular distribution has a reduced sensitivity to several predominant experimental uncertainties (e.g. the jet energy scale and luminosity uncertainties). The dijet angular distribution is therefore well suited to test the predictions of QCD and to search for signals of new physics, in particular for signs of quark compositeness. In the following a measurement of the dijet angular distributions and a search for quark compositeness with the CMS experiment is presented. (orig.)

  4. Search for New Physics Processes with Heavy Quark Signatures in the ATLAS Experiment

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00388427

    A program involving searches for new physics with heavy quark final states using data from the ATLAS experiment at the LHC is presented here. The signal and expected backgrounds for the decay $B_{s}→μ^{+} μ^{-} μ^{+} μ^{-}$, a rare decay whose branching ratio may be enhanced by the presence of certain Beyond the Standard Model processes, are studied, and the groundwork is laid for a future analysis. Possible mediators include horizontal gauge bosons, supersymmetry via sgoldstinos, and interactions with the hidden sector. To this end, a set of twelve triggers have been selected and studied, and their efficiency figures of merit have been calculated. A truth trigger efficiency study was performed in order to determine if new triggers should be installed for the analysis. The backgrounds have been studied, and a mass window technique was used to reduce their amplitude relative to the signal. A proposal to improve the efficiency of some of the ATLAS High-Level B-physics Triggers, based on refining the selec...

  5. Neutrino-4 experiment on search for sterile neutrino with multi-section model of detector

    CERN Document Server

    Serebrov, A P; Samoilov, R M; Fomin, A K; Zinoviev, V G; Neustroev, P V; Golovtsov, V L; Gruzinskiy, N V; Solovey, V A; Chernyj, A V; Zherebtsov, O M; Martemyanov, V P; Tsynoev, V G; Tarasenkov, V G; Aleshin, V I; Petelin, A L; Ishutov, A L; Tuzov, A A; Sazontov, S A; Ryazanov, D K; Gromov, M O; Afanasiev, V V; Zaytsev, M E; Chaikovskii, M E

    2016-01-01

    In order to carry out research in the field of possible existence of sterile neutrino the laboratory based on SM-3 reactor (Dimitrovgrad, Russia) was created to search for oscillations of reactor antineutrino. The prototype of a multi-section neutrino detector with liquid scintillator volume of 350 l was installed in the middle of 2015. It is a moveable inside the passive shielding detector, which can be set at distance range from 6 to 11 meters from the reactor core. The measurements of antineutrino flux at such small distances from the reactor core carried out for the first time. The different methods of cosmic background suppression were researched in order to increase the precision of the experiment. After collecting data for half a year, measurement accuracy for the nearest point (6.5 m) comprised 10%. The full-scale detector with volume of liquid scintillator 3 m3 (5x10 sections) is at the stage of preparation. It will allow us to obtain up to 1.5-3.0% statistic accuracy of measurements at the distances...

  6. Search for the Standard Model Higgs boson decaying to $b$ quarks with the CMS experiment

    CERN Document Server

    Donato, Silvio; Rizzi, Andrea

    2017-01-01

    Chapter 1 describes the theory of the Higgs boson in the framework of the SM and gives an overview of the physics of the Higgs boson and of its search performed by the CMS and ATLAS collaborations during the LHC Run 1. Chapter 2 introduces the CMS experiment at the LHC and the event reconstruction used by CMS. My contribution to the event reconstruction is an improvement of the tracking in the core of energetic jets, described in Appendix A. The last section of this Chapter will present the trigger system of CMS, with special attention to the High Level Trigger (HLT). The whole Chapter 3 is devoted to the description of the trigger improvements that I developed during my Ph.D. One of the most important achievements is a fast track- ing that allows to identify pile-up jets for any event accepted by the hardware trigger (∼ 100 kHz). This fast tracking exploits a novel algorithm, the Fast Primary Vertex, that localizes the primary vertex without using tracks, but just hits recorded by the pixel detector and je...

  7. Search For Resonances In The Dijet Mass Spectrum With The ATLAS Experiment At The LHC

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00339090

    The unprecedented collision energy reached and the considerable integrated luminosity produced by the LHC allow its experiments to investigate the existence of new physics phenomena beyond the Standard Model of particle physics at the TeV scale. This thesis presents the search performed by the ATLAS Collaboration for evidence of new physics manifesting as localised resonances in the dijet invariant mass distribution of events with large transverse momenta. No evidence of resonant phenomena outside of the Standard Model have been observed in the 20.3 fb$^{-1}$ of data collected in 2012 at $\\sqrt{s}$ = 8 TeV nor in the 3.6 fb$^{-1}$ of data collected in 2015 at $\\sqrt{s}$ = 13 TeV. Limits have been set at 95% Credibility Level on the cross-section times acceptance of selected benchmark models. Excited quarks with masses below 4.06 TeV and Quantum Black Holes, QBH, with masses below 5.2 TeV have been excluded using the 2012 datasets. These limits have then been further extended to 5.66 TeV (excited quarks) and ...

  8. Search for Solar Axions with the CCD Detector and X-ray Telescope at CAST Experiment

    CERN Document Server

    Rosu, Madalin Mihai; Zioutas, Konstantin

    2015-06-09

    The CERN Axion Solar Telescope (CAST) is an experiment that uses the world’s highest sensitivity Helioscope to date for solar Axions searches. Axions are weakly interacting pseudoscalar particles proposed to solve the so-called Strong Charge-Parity Problem of the Standard Model. The principle of detection is the inverse Primakoff Effect, which is a mechanism for converting the Axions into easily detectable X-ray photons in a strong transverse magnetic field. The solar Axions are produced due to the Primakoff effect in the hot and dense core of from the coupling of a real and a virtual photon. The solar models predict a peak Axion luminosity at an energy of 3 keV originating mostly from the inner 20% of the solar radius. Thus an intensity peak at an energy of 3 keV is also expected in the case of the X-ray radiation resulting from Axion conversion. CAST uses a high precision movement system for tracking the Sun twice a day with a LHC dipole twin aperture prototype magnet, 9.26 meters long and with a field of...

  9. Positronium Portal into Hidden Sector: A new Experiment to Search for Mirror Dark Matter

    CERN Document Server

    Crivelli, Paolo; Gendotti, Ulisse; Gninenko, Sergei; Rubbia, Andre

    2010-01-01

    The understanding of the origin of dark matter has great importance for cosmology and particle physics. Several interesting extensions of the standard model dealing with solution of this problem motivate the concept of hidden sectors consisting of SU(3)xSU(2)_LxU(1)_Y singlet fields. Among these models, the mirror matter model is certainly one of the most interesting. The model explains the origin of parity violation in weak interactions, it could also explain the baryon asymmetry of the Universe and provide a natural ground for the explanation of dark matter. The mirror matter could have a portal to our world through photon-mirror photon mixing (epsilon). This mixing would lead to orthopositronium (o-Ps) to mirror orthopositronium oscillations, the experimental signature of which is the apparently invisible decay of o-Ps. In this paper, we describe an experiment to search for the decay o-Ps -> invisible in vacuum by using a pulsed slow positron beam and a massive 4pi BGO crystal calorimeter. The developed hi...

  10. Search for Higgs bosons and for Supersymmetric particles at particle collider experiments

    CERN Document Server

    Muanza, Steve

    The corner stone of the Standard Model (SM) of Particle Physics is the Higgs mechanism. It explains how the bosons W, Z and H acquire a mass via weak interactions. In addition it explains how the charged fermions also acquire a mass through Yukawa interactions. And on top of this, it regularizes the scattering of longitudinal W and Z bosons at high energy. The discovery of a Higgs boson by the ATLAS and the CMS collaborations in 2012 marked the culminating success of the SM at explaining most of the known phenomena. However a few other phenomena such as the Dark Matter and the Dark energy cannot be explained by the SM particles. What's more, the SM leaves several open questions such as a quest for a quantum theory for gravity, the naturalness in the Higgs sector, a possible Grand Unification,... The common thread in topics presented in this habilitation thesis is the search for manifestations of a TeV scale supersymmetric (SUSY) extension of the Standard Model at particle collider experiments. Among the predi...

  11. Search for the {theta}{sub 13} mixing angle with the Double Chooz experiment

    Energy Technology Data Exchange (ETDEWEB)

    Gil-Botella, Ines, E-mail: ines.gil@ciemat.es [CIEMAT, Basic Research Department, Avenida Complutense, 22, 28040 Madrid (Spain)

    2010-11-01

    The Double Chooz reactor neutrino experiment will search for a non vanishing {theta}{sub 13} mixing angle with unprecedented sensitivity, which might open the way to unveiling CP violation in the leptonic sector. The measurement of this angle will be based in a precise comparison of the antineutrino spectrum at two identical detectors located at different distances from the Chooz nuclear reactor cores in France. Double Chooz is particularly attractive because of its capability to measure sin{sup 2}(2{theta}{sub 13}) to 3{sigma} if sin{sup 2}(2{theta}{sub 13}) > 0.05 or to exclude sin{sup 2}(2{theta}{sub 13}) down to 0.03 at 90% C.L. for {Delta}m{sup 2}{sub 31} = 2.5 x 10{sup -3} eV{sup 2} in three years of data taking with both detectors. The installation of the far detector at 1 km from the reactors is almost completed and the first neutrino interactions are expected by end 2010.

  12. Search for Stable Hadronising Squarks and Gluinos at the ATLAS Experiment at the LHC

    CERN Document Server

    Aad, Georges; Abdallah, Jalal; Abdelalim, Ahmed Ali; Abdesselam, Abdelouahab; Abdinov, Ovsat; Abi, Babak; Abolins, Maris; Abramowicz, Halina; Abreu, Henso; Acerbi, Emilio; Acharya, Bobby Samir; Adams, David; Addy, Tetteh; Adelman, Jahred; Aderholz, Michael; Adomeit, Stefanie; Adragna, Paolo; Adye, Tim; Aefsky, Scott; Aguilar-Saavedra, Juan Antonio; Aharrouche, Mohamed; Ahlen, Steven; Ahles, Florian; Ahmad, Ashfaq; Ahsan, Mahsana; Aielli, Giulio; Akdogan, Taylan; Akesson, Torsten Paul; Akimoto, Ginga; Akimov, Andrei; Alam, Mohammad; Alam, Muhammad Aftab; Albrand, Solveig; Aleksa, Martin; Aleksandrov, Igor; Aleppo, Mario; Alessandria, Franco; Alexa, Calin; Alexander, Gideon; Alexandre, Gauthier; Alexopoulos, Theodoros; Alhroob, Muhammad; Aliev, Malik; Alimonti, Gianluca; Alison, John; Aliyev, Magsud; Allport, Phillip; Allwood-Spiers, Sarah; Almond, John; Aloisio, Alberto; Alon, Raz; Alonso, Alejandro; Alviggi, Mariagrazia; Amako, Katsuya; Amaral, Pedro; Amelung, Christoph; Ammosov, Vladimir; Amorim, Antonio; Amoros, Gabriel; Amram, Nir; Anastopoulos, Christos; Andeen, Timothy; Anders, Christoph Falk; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Andrieux, Marie-Laure; Anduaga, Xabier; Angerami, Aaron; Anghinolfi, Francis; Anjos, Nuno; Annovi, Alberto; Antonaki, Ariadni; Antonelli, Mario; Antonelli, Stefano; Antos, Jaroslav; Anulli, Fabio; Aoun, Sahar; Aperio Bella, Ludovica; Apolle, Rudi; Arabidze, Giorgi; Aracena, Ignacio; Arai, Yasuo; Arce, Ayana; Archambault, John-Paul; Arfaoui, Samir; Arguin, Jean-Francois; Arik, Engin; Arik, Metin; Armbruster, Aaron James; Arnaez, Olivier; Arnault, Christian; Artamonov, Andrei; Artoni, Giacomo; Arutinov, David; Asai, Shoji; Asfandiyarov, Ruslan; Ask, Stefan; Asman, Barbro; Asquith, Lily; Assamagan, Ketevi; Astbury, Alan; Astvatsatourov, Anatoli; Atoian, Grigor; Aubert, Bernard; Auerbach, Benjamin; Auge, Etienne; Augsten, Kamil; Aurousseau, Mathieu; Austin, Nicholas; Avramidou, Rachel Maria; Axen, David; Ay, Cano; Azuelos, Georges; Azuma, Yuya; Baak, Max; Baccaglioni, Giuseppe; Bacci, Cesare; Bach, Andre; Bachacou, Henri; Bachas, Konstantinos; Bachy, Gerard; Backes, Moritz; Backhaus, Malte; Badescu, Elisabeta; Bagnaia, Paolo; Bahinipati, Seema; Bai, Yu; Bailey, David; Bain, Travis; Baines, John; Baker, Oliver Keith; Baker, Mark; Baker, Sarah; Baltasar Dos Santos Pedrosa, Fernando; Banas, Elzbieta; Banerjee, Piyali; Banerjee, Swagato; Banfi, Danilo; Bangert, Andrea Michelle; Bansal, Vikas; Bansil, Hardeep Singh; Barak, Liron; Baranov, Sergei; Barashkou, Andrei; Galtieri, Angela Barbaro; Barber, Tom; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Bardin, Dmitri; Barillari, Teresa; Barisonzi, Marcello; Barklow, Timothy; Barlow, Nick; Barnett, Bruce; Barnett, Michael; Baroncelli, Antonio; Barr, Alan; Barreiro, Fernando; Barreiro Guimaraes da Costa, Joao; Barrillon, Pierre; Bartoldus, Rainer; Barton, Adam Edward; Bartsch, Detlef; Bates, Richard; Batkova, Lucia; Batley, Richard; Battaglia, Andreas; Battistin, Michele; Battistoni, Giuseppe; Bauer, Florian; Bawa, Harinder Singh; Beare, Brian; Beau, Tristan; Beauchemin, Pierre-Hugues; Beccherle, Roberto; Bechtle, Philip; Beck, Hans Peter; Beckingham, Matthew; Becks, Karl-Heinz; Beddall, Andrew; Beddall, Ayda; Bednyakov, Vadim; Bee, Christopher; Begel, Michael; Behar Harpaz, Silvia; Behera, Prafulla; Beimforde, Michael; Belanger-Champagne, Camille; Bell, Paul; Bell, William; Bella, Gideon; Bellagamba, Lorenzo; Bellina, Francesco; Bellomo, Giovanni; Bellomo, Massimiliano; Belloni, Alberto; Beloborodova, Olga; Belotskiy, Konstantin; Beltramello, Olga; Ben Ami, Sagi; Benary, Odette; Benchekroun, Driss; Benchouk, Chafik; Bendel, Markus; Benedict, Brian Hugues; Benekos, Nektarios; Benhammou, Yan; Benjamin, Douglas; Benoit, Mathieu; Bensinger, James; Benslama, Kamal; Bentvelsen, Stan; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Berghaus, Frank; Berglund, Elina; Beringer, Jurg; Bernardet, Karim; Bernat, Pauline; Bernhard, Ralf; Bernius, Catrin; Berry, Tracey; Bertin, Antonio; Bertinelli, Francesco; Bertolucci, Federico; Besana, Maria Ilaria; Besson, Nathalie; Bethke, Siegfried; Bhimji, Wahid; Bianchi, Riccardo-Maria; Bianco, Michele; Biebel, Otmar; Bieniek, Stephen Paul; Biesiada, Jed; Biglietti, Michela; Bilokon, Halina; Bindi, Marcello; Binet, Sebastien; Bingul, Ahmet; Bini, Cesare; Biscarat, Catherine; Bitenc, Urban; Black, Kevin; Blair, Robert; Blanchard, Jean-Baptiste; Blanchot, Georges; Blocker, Craig; Blocki, Jacek; Blondel, Alain; Blum, Walter; Blumenschein, Ulrike; Bobbink, Gerjan; Bobrovnikov, Victor

    2011-06-27

    Hitherto unobserved long-lived massive particles with electric and/or colour charge are predicted by a range of theories which extend the Standard Model. In this paper a search is performed at the ATLAS experiment for slow-moving charged particles produced in proton-proton collisions at 7 TeV centre-of-mass energy at the LHC, using a data-set corresponding to an integrated luminosity of 34 pb-1. No deviations from Standard Model expectations are found. This result is interpreted in a framework of supersymmetry models in which coloured sparticles can hadronise into long-lived bound hadronic states, termed R-hadrons, and 95% CL limits are set on the production cross-sections of squarks and gluinos. The in influence of R-hadron interactions in matter was studied using a number of different models, and lower mass limits for stable sbottoms and stops are found to be 294 and 309 GeV respectively. The lower mass limit for a stable gluino lies in the range from 562 to 586 GeV depending on the model assumed. Each of t...

  13. The cryogenic system for the Panda-X dark matter search experiment

    Science.gov (United States)

    Gong, H.; Giboni, K. L.; Ji, X.; Tan, A.; Zhao, L.

    2013-01-01

    Panda-X is a liquid xenon dual-phase detector for the Dark Matter Search. The first modestly-sized module will soon be installed in the China JinPing Deep Underground Laboratory in Sichuan province, P.R. China. The cryogenic system is designed to handle much larger detectors, even the final version in the ton scale. Special attention has been paid to the reliability, serviceability, and adaptability to the requirements of a growing experiment. The system is cooled by a single Iwatani PC150 Pulse Tube Refrigerator. After subtracting all thermal losses, the remaining cooling power is still 82 W. The fill speed was 0.75 g/s, but could be boosted by LN2 assisted cooling to 3.3 g/s. For the continuous recirculation and purification through a hot getter, a heat exchanger was employed to reduce the required cooling power. The recirculation speed is limited to 2.9 g/s by the gas pump. At this speed, recirculation only adds 18.5 W to the heat load of the system, corresponding to a 95.2 % efficiency of the heat exchanger.

  14. Searches for Dark Matter and Large Extra Dimensions in Monojet Final States with the ATLAS Experiment

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00286734

    This thesis presents searches for evidence for Weakly Interacting Massive Particles (WIMPs) and Extra Dimensions in proton-proton collisions recorded by the ATLAS experiment at the CERN Large Hadron Collider (LHC). The WIMP is one of the main candidates to constitute the particle content of Dark Matter. Extra Dimensions are introduced in several theories in order to explain the apparent weakness of gravity when compared to the other interactions in Nature. Theories with WIMPs as well as Extra Dimensions can manifest themselves at the LHC, with experimental signatures characterized by an energetic hadronic jet associated with large missing momentum. These signatures are known as monojet signatures, and are investigated in this thesis. The first analysis is performed using L = 20.3 fb$^{-1}$~of proton-proton collisions at $\\sqrt{s}$ = 8 TeV recorded in the ATLAS Run 1. The second analysis is performed using L = 3.2 fb$^{-1}$~of proton-proton collisions at $\\sqrt{s}$ = 13 TeV recorded in the ATLAS Run 2. No sign...

  15. The Gerda experiment for the search of 0{nu}{beta}{beta} decay in {sup 76}Ge

    Energy Technology Data Exchange (ETDEWEB)

    Ackermann, K.H.; Altmann, M.; Becerici-Schmidt, N.; Caldwell, A.; Cossavella, F.; Lenz, D.; Liao, H.; Majorovits, B.; Mayer, S.; O' Shaughnessy, C.; Schubert, J.; Schulz, O.; Seitz, H.; Stelzer, F.; Vogt, S.; Volynets, O. [Max-Planck-Institut fuer Physik, Muenchen (Germany); Agostini, M.; Bode, T.; Budjas, D.; Janicsko Csathy, J.; Lazzaro, A.; Schoenert, S. [Technische Universitaet Muenchen, Physik Department and Excellence Cluster Universe, Munich (Germany); Allardt, M.; Barros, N.; Domula, A.; Lehnert, B.; Zuber, K. [Technische Universitaet Dresden, Institut fuer Kern- und Teilchenphysik, Dresden (Germany); Andreotti, E. [Institute for Reference Materials and Measurements, Geel (Belgium); Eberhard Karls Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Bakalyarov, A.M.; Belyaev, S.T.; Lebedev, V.I.; Zhukov, S.V. [National Research Centre ' ' Kurchatov Institute' ' , Moscow (Russian Federation); Balata, M.; Ioannucci, L.; Junker, M.; Laubenstein, M.; Nisi, S.; Pandola, L. [LNGS, INFN Laboratori Nazionali del Gran Sasso, Assergi (Italy); Barabanov, I.; Bezrukov, L.; Denisov, A.; Gurentsov, V.; Kianovsky, S.; Kusminov, V.; Lubsandorzhiev, B.; Yanovich, E. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Barnabe Heider, M. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Technische Universitaet Muenchen, Physik Department and Excellence Cluster Universe, Munich (Germany); CEGEP St-Hyacinthe, Quebec (Canada); Baudis, L.; Benato, G.; Ferella, A.; Froborg, F.; Guthikonda, K.K.; Tarka, M.; Walter, M. [Physik Institut der Universitaet Zuerich, Zuerich (Switzerland); Bauer, C.; Hampel, W.; Heisel, M.; Heusser, G.; Hofmann, W.; Kankanyan, R.; Kihm, T.; Kiko, J.; Kirsch, A.; Knoepfle, K.T.; Lindner, M.; Lubashevskiy, A.; Machado, A.A.; Maneschg, W.; Oehm, J.; Salathe, M.; Schreiner, J.; Schwan, U.; Schwingenheuer, B.; Simgen, H.; Smolnikov, A.; Strecker, H.; Wagner, V.; Wegmann, A. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Bellotti, E. [Universita Milano Bicocca, Dipartimento di Fisica, Milano (Italy); INFN Milano Bicocca, Milano (Italy); Belogurov, S.; Kornoukhov, V.N. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Bettini, A.; Brugnera, R.; Garfagnini, A.; Hemmer, S.; Sada, C. [Dipartimento di Fisica e Astronomia dell' Universita di Padova, Padova (Italy); INFN Padova, Padova (Italy); Brudanin, V.; Egorov, V.; Kochetov, O.; Nemchenok, I.; Shevchik, E.; Zhitnikov, I.; Zinatulina, D. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Cattadori, C. [INFN Milano Bicocca, Milano (Italy); Chernogorov, A.; Demidova, E.V.; Kirpichnikov, I.V.; Vasenko, A.A. [Institute for Theoretical and Experimental Physics, Moscow (Russian Federation); Chkvorets, O. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Laurentian University, Sudbury (Canada); D' Andragora, A. [LNGS, INFN Laboratori Nazionali del Gran Sasso, Assergi (Italy); Brookhaven National Laboratory, Upton, NY (United States); Di Vacri, A. [LNGS, INFN Laboratori Nazionali del Gran Sasso, Assergi (Italy); University ' ' G. d' Annunzio' ' di Chieti-Pescara, Department of Neurosciences and Imaging, Chieti (Italy); Falkenstein, R.; Freund, K.; Grabmayr, P.; Hegai, A.; Jochum, J.; Knapp, M.; Niedermeier, L.; Schmitt, C.; Sturm, K. von [Eberhard Karls Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Frodyma, N.; Pelczar, K.; Wojcik, M.; Zuzel, G. [Jagiellonian University, Institute of Physics, Cracow (Poland); Gangapshev, A. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Gasparro, J. [Institute for Reference Materials and Measurements, Geel (Belgium); National Physical Laboratory, Teddigton (United Kingdom); Gazzana, S. [LNGS, INFN Laboratori Nazionali del Gran Sasso, Assergi (Italy); Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Gonzalez de Orduna, R.; Hult, M.; Marissens, G. [Institute for Reference Materials and Measurements, Geel (Belgium); Gusev, K. [Joint Institute for Nuclear Research, Dubna (Russian Federation); National Research Centre ' ' Kurchatov Institute' ' , Moscow (Russian Federation); Technische Universitaet Muenchen, Physik Department and Excellence Cluster Universe, Munich (Germany); Inzhechik, L.V. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Moscow Institute of Physics and Technology, Moscow (Russian Federation); Klimenko, A. [Joint Institute for Nuclear Research, Dubna (Russian Federation); Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Institute for Nuclear Research of the Russian Academy of Sciences, Moscow (Russian Federation); Kroeninger, K. [Max-Planck-Institut fuer Physik, Muenchen (Germany); U. Goettingen, II. Physikalisches Institut, Goettingen (Germany); U. Siegen, Department Physik, Siegen (Germany); Lippi, I.; Rossi Alvarez, C.; Stanco, L.; Ur, C.A. [INFN Padova, Padova (Italy); Liu, J. [Max-Planck-Institut fuer Physik, Muenchen (Germany); University of Tokyo, Kavli IPMU, Tokyo (Japan); Liu, X. [Shanghai Jiaotong University, Shanghai (China); Meierhofer, G. [Eberhard Karls Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); TUeV-SUeD, Muenchen (Germany); Peiffer, P. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany); Pullia, A.; Riboldi, S. [Universita degli Studi di Milano (Italy); INFN Milano, Dipartimento di Fisica, Milano (Italy); Ritter, F. [Eberhard Karls Universitaet Tuebingen, Physikalisches Institut, Tuebingen (Germany); Robert Bosch GmbH, Reutlingen (Germany); Shirchenko, M. [Joint Institute for Nuclear Research, Dubna (Russian Federation); National Research Centre ' ' Kurchatov Institute' ' , Moscow (Russian Federation); Trunk, U. [Max Planck Institut fuer Kernphysik, Heidelberg (Germany); DESY, Photon-Science Detector Group, Hamburg (Germany); Zavarise, P. [LNGS, INFN Laboratori Nazionali del Gran Sasso, Assergi (Italy); University of L' Aquila, Dipartimento di Fisica, L' Aquila (Italy)

    2013-03-15

    The Gerda collaboration is performing a search for neutrinoless double beta decay of {sup 76}Ge with the eponymous detector. The experiment has been installed and commissioned at the Laboratori Nazionali del Gran Sasso and has started operation in November 2011. The design, construction and first operational results are described, along with detailed information from the R and D phase. (orig.)

  16. Jagiellonian University Searches for the Standard Model Higgs boson decay to $\\tau $ lepton pairs at the CMS experiment

    CERN Document Server

    Pyskir, Andrzej

    2017-01-01

    We present results of searches for the Standard Model Higgs boson decaying to tau lepton pairs at the CMS experiment with data collected during the LHC Run 1. We also present some insight into the analysis with Run 2 data. CP sensitive variables are described and an experimental method of probing CP of the Higgs boson is presented.

  17. The COBE Diffuse Infrared Background Experiment search for thecosmic infrared background. I. Limits and detections

    Energy Technology Data Exchange (ETDEWEB)

    Hauser, M.G.; Arendt, R.G.; Kelsall, T.; Dwek, E.; Odegard, N.; Weiland, J.L.; Freudenreich, H.T.; Reach, W.T.; Silverberg, R.F.; Moseley, S.H.; Pei, Y.C.; Lubin, P.; Mather, J.C.; Shafer, R.A.; Smoot,G.F.; Weiss, R.; Wilkinson, D.T.; Wright, E.L.

    1998-01-06

    The Diffuse Infrared Background Experiment (DIRBE) on the Cosmic Background Explorer (COBE) spacecraft was designed primarily to conduct a systematic search for an isotropic cosmic infrared background (CIB) in 10 photometric bands from 1.25 to 240 mu m. The results of that search are presented here. Conservative limits on the CIB are obtained from the minimum observed brightness in all-sky maps at each wavelength, with the faintest limits in the DIRBE spectral range being at 3.5 mu m(nu l nu<64 nW m-2 sr-1, 95 percent confidence level) and at 240 mu m (nu l nu < 28 nW m-1 sr-1, 95 percent confidence level). The bright foregrounds from interplanetary dust scattering and emission, stars, and interstellar dust emission are the principal impediments to the DIRBE measurements of the CIB. These foregrounds have been modeled and removed from the sky maps. Assessment of the random and systematic uncertainties in the residuals and tests for isotropy show that only the 140 and 240 mum data provide candidate detections of the CIB. The residuals and their uncertainties provide CIB upper limits more restrictive than the dark sky limits at wavelengths from 1.25 to 100 mu m. No plausible solar system or Galactic source of the observed 140 and 240 mu m residuals can be identified, leading to the conclusion that the CIB has been detected at levels of nu l nu = 25 +- 7 and 14 +- 3 nW m-2 sr-1 at 140 and 240 mu m, respectively. The integrated energy from 140 to 240 mu m, 10.3 nW m-2sr-1, is about twice the integrated optical light from the galaxies in the Hubble Deep Field, suggesting that star formation might have been heavily enshrouded by dust at high redshift. The detections and upper limits reported here provide new constraints on models of the history of energy-releasing processes and dust production since the decoupling of the cosmic microwave background from matter.

  18. A search for new heavy particles in events with highly ionising, short tracks at the CMS experiment

    CERN Document Server

    Lenz, Teresa; Schleper, Peter

    2016-01-01

    The main focus of the CMS experiment at the Large Hadron Collider (LHC) is to search for physics beyond the Standard Model and to measure Standard Model parameters. For both purposes it is essential to determine important performance parameters of the CMS detector. The here presented thesis contributes in a twofold way to the physics program of CMS. In the first part of this thesis, a search for physics beyond the Standard Model is presented. It is motivated by supersymmetric models with nearly mass-degenerate lightest neutralinos and lightest charginos. The small mass gap between chargino and neutralino can lead to long lifetimes of the chargino due to phase space suppression. Thus, the chargino can reach the tracking system before its decay. The here presented search targets chargino lifetimes of $\\text{c}\\tau \\approx 1 - 30\\,\\text{cm}$ where most of the charginos decay in the first layers of the tracker. This search aims at increasing the search sensitivity of existing searches with respect to these models...

  19. Recent results on searches for R-parity conserving supersymmetry at the ATLAS experiment

    CERN Document Server

    Klimek, P; The ATLAS collaboration

    2014-01-01

    Despite the absence of experimental evidence, weak scale supersymmetry remains one of the best motivated and studied Standard Model extensions. This talk summarizes recent ATLAS results on searches for R-Parity conserving supersymmetric models. Promptly decaying squarks, gluinos, charginos and neutralinos are searched for in events characterized by missing transverse momentum, possibly jets and/or light leptons, taus or photons.

  20. Experiments on the search for the NN-decoupled NN{pi}-resonance d'

    Energy Technology Data Exchange (ETDEWEB)

    Doroshkevich, E.; Brodowski, W.; Paetzold, J.; Clement, H.; Meier, R.; Wagner, G.J. [Physikalisches Institut, Universitaet Tuebingen, Auf der Morgenstelle 14, 72076, Tuebingen (Germany)

    2003-11-01

    The status on the search for NN-decoupled NN{pi}-resonances is reviewed with regard to recent experimental searches in the pionic double-charge exchange in nuclei, the two-pion production in nucleon-nucleon collisions, the photo pion-production on the deuteron and the electro pion-production in nuclei. (orig.)

  1. The Interplay Between Collider Searches For Supersymmetric Higgs Bosons and Direct Dark Matter Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Carena, Marcela; Hooper, Dan; /Fermilab; Vallinotto, Alberto; /Fermilab /Chicago U. /Paris, Inst. Astrophys.

    2006-11-01

    In this article, we explore the interplay between searches for supersymmetric particles and Higgs bosons at hadron colliders (the Tevatron and the LHC) and direct dark matter searches (such as CDMS, ZEPLIN, XENON, EDELWEISS, CRESST, WARP and others). We focus on collider searches for heavy MSSM Higgs bosons (A, H, H{sup {+-}}) and how the prospects for these searches are impacted by direct dark matter limits and vice versa. We find that the prospects of these two experimental programs are highly interrelated. A positive detection of A, H or H{sup {+-}} at the Tevatron would dramatically enhance the prospects for a near future direct discovery of neutralino dark matter. Similarly, a positive direct detection of neutralino dark matter would enhance the prospects of discovering heavy MSSM Higgs bosons at the Tevatron or the LHC. Combining the information obtained from both types of experimental searches will enable us to learn more about the nature of supersymmetry.

  2. Personalized Search

    CERN Document Server

    AUTHOR|(SzGeCERN)749939

    2015-01-01

    As the volume of electronically available information grows, relevant items become harder to find. This work presents an approach to personalizing search results in scientific publication databases. This work focuses on re-ranking search results from existing search engines like Solr or ElasticSearch. This work also includes the development of Obelix, a new recommendation system used to re-rank search results. The project was proposed and performed at CERN, using the scientific publications available on the CERN Document Server (CDS). This work experiments with re-ranking using offline and online evaluation of users and documents in CDS. The experiments conclude that the personalized search result outperform both latest first and word similarity in terms of click position in the search result for global search in CDS.

  3. Search for a Heavy Neutral Higgs Boson decaying into Tau Pairs with the CMS Experiment at the LHC

    CERN Document Server

    Calligaris, Luigi

    2015-01-01

    A search for a heavy MSSM Higgs boson is performed in the φ → τ τ → eµ decaychannel, using data corresponding to an integrated luminosity of 19.7 fb−1 at a p-pcenter of mass energy of 8 TeV, collected by the CMS experiment at the Large HadronCollider. The search is optimized for Higgs boson masses between 300 and 1000 GeVand makes the use of Boosted Decision Trees for an improved selection of signal events.The results are consistent with the predictions of the Standard Model.

  4. Optical counterpart of the Foucault pendulum

    CERN Document Server

    Okulov, A Yu

    2011-01-01

    The rotation of the Earth was one of the most controversial issues of natural philosophy during centuries in transition from medieval to Renaissances and afterwards. The invention of Foucault pendulum \\cite {Foucault:1852} did not stopped this controversies but further stimulated the new searches of the Earth motion with respect to the "eather wind" which led to Michelson interferometric studies of small displacements and stars dimensions \\cite {Michelson:1904} and to the Saqnac discovery of the phase lag of counter propagating waves caused by rotation of the reference frame \\cite {Sagnac:1913}. Nowadays the Sagnac effect is in the heart of the widespread rotation sensors, technically implemented as a passive fiber gyroscopes and the active laser gyros \\cite {Scully:1997}. The recent activity of researchers is focused upon the photon's rotation, observable as optical vortices \\cite {Padgett:2009, Soskin:2008}. In contrast to classical top the photon has a very remarkable difference: the projection of the angu...

  5. Electromagnetic calorimeter for the Heavy Photon Search Experiment at Jefferson Lab

    Energy Technology Data Exchange (ETDEWEB)

    Buchanan, Emma [Univ. of Glasgow, Scotland (United Kingdom)

    2014-11-01

    The Heavy Photon Search Experiment (HPS) seeks to detect a hypothesised hidden sector boson, the A', predicted to be produced in dark matter decay or annihilation. Theories suggest that the A' couples weakly to electric charge through kinetic mixing, allowing it, as a result, to decay to Standard Matter (SM) lepton pair, which may explain the electron and positron excess recently observed in cosmic rays. Measuring the lepton pair decay of the A' could lead to indirect detection of dark matter. The HPS experiment is a fixed target experiment that will utilize the electron beam produced at the Thomas Jefferson National Accelerator Facility (Jefferson Lab). The detector set-up includes a silicon vertex tracker (SVT) and an Electromagnetic Calorimeter (ECal). The ECal will provide the trigger and detect e+e- pairs and its construction and testing forms the focus of this thesis. The ECal consists of 442 PbWO4- tapered crystals with a length 16cm and a 1.6x1.6cm2 cross-section, stacked into a rectangular array and are coupled to Large Area APDs and corresponding pre-amplifiers. Supplementary to the ECal is a Light Monitoring System (LMS) consisting of bi-coloured LEDs that will monitor changes in APD gain and crystal transparency due to radiation damage. Before construction of the ECal each of the components were required to be individually tested to determine a number of different characteristics. Irradiation tests were performed on PbWO4 ECal crystals and, as a comparison, one grown by a different manufacturer to determine their radiation hardness. A technique for annealing the radiation damage by optical bleaching, which involves injecting light of various wavelengths into the crystal, was tested using the blue LED from the LMS as a potential candidate. The light yield dependence on temperature was also measured for one of the PbWO4 crystal types. Each APD was individually tested to determine if they

  6. New Physics search with Experiment E36 at J-PARC

    Science.gov (United States)

    Dongwi, Dongwi H.; TREK Collaboration

    2017-01-01

    We are potentially standing at the precipice in the quest for discovery of New Physics (NP) beyond the SM by performing a precision test of lepton universality. Experiment E36 conducted at J-PARC in Japan tests lepton universality in the RK = Γ(Ke 2) / Γ(Kμ 2) ratio. In the SM, the ratio of leptonic K+ decays is highly precise with an uncertainty of ΔRK /RK = 4 .10-4 . Any observed deviation from the SM prediction would break the universality of the lepton couplings and provide a clear indication of NP beyond the SM. The E36 detector apparatus allows sensitivity to search for sterile neutrinos below 300 MeV/c2 and light U(1) gauge bosons, which could be associated with dark matter or explain established muon-related anomalies such as the muon g-2 value, and perhaps the proton radius puzzle. E36 data taking was completed in 2015. A scintillating fiber target was used to stop a beam of up to 1.2 Million K+ per spill. K+ decay products were detected with a large-acceptance toroidal spectrometer capable of tracking charged particles with high resolution, combined with a CsI(Tl) photon calorimeter with large solid angle covering 75 % of 4 π and particle identification systems. The status of the data analysis will be presented. This work has been supported by DOE awards DE-SC0003884 and DE-SC0013941 in the US, NSERC in Canada, and Kaken-hi in Japan.

  7. Search for resonances in the di-photon channel with the ATLAS experiment at the LHC

    CERN Document Server

    Mazza, Simone Michele; The ATLAS collaboration

    2016-01-01

    A search for resonances decaying to two photons is presented. Benchmark signal model of a spin-2 Randall-Sundrum graviton and a spin-0 higgs-like state were used. The analysis uses 3.2 fb −1 (2015) and 12.2 fb −1 (2016) of pp data recorded with the ATLAS detector at the LHC in 2015 and 2016. Results for 2015 data are presented for the spin-2 RS Graviton search, while results for 2015 and 2016 data are presented for the spin-0 Higgs search

  8. Dark Matter Searches and Combined Interpretations at the ATLAS Experiment at 13 TeV

    CERN Document Server

    Beacham, James; The ATLAS collaboration

    2016-01-01

    Dark matter (DM) particles can be produced at the LHC in association with other particles, which mainly come from initial state radiation. Searches for such phenomena in events with jets, photons, electroweak gauge bosons or Higgs bosons recoiling against large missing transverse momentum (originating from DM particles) in ATLAS at 13 TeV are presented. The results are interpreted in the framework of simplified models with pair production of Weakly Interacting Massive Particles (WIMPs) and effective field theories. Constraints from dijet searches are compared with results from the “Mono-X” searches, providing combined interpretation in the framework of simplified model.

  9. Model-independent search for new physics at D0 experiment

    Indian Academy of Sciences (India)

    Md Naimuddin

    2012-11-01

    Finding the evidence of new physics beyond the Standard Model is one of the primary goals of RunII of the Tevatron. Many dedicated searches for new physics are ongoing at the Tevatron but in order to broaden the scope and maximize the chances of finding the new physics, we also search in a model-independent way. The results of such searches for indications of new physics at the electroweak scale are presented using data collected using the D0 detector from $p\\bar{p}$-interactions at $\\sqrt{s} = 1.96$ TeV.

  10. A Low-Threshold Analysis of Data from the Cryogenic Dark Matter Search Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bunker, Raymond [Univ. of California, Santa Barbara, CA (United States)

    2011-12-01

    Although dark matter appears to constitute over 80% of the matter in the Universe, its composition is a mystery. Astrophysical observations suggest that the luminous portions of the Galaxy are embedded in a halo of darkmatter particles. Weakly Interacting Massive Particles (WIMPs) are the most studied class of dark-matter candidates and arise naturally within the context of many weak-scale supersymmetric theories. Direct-detection experiments like the Cryogenic Dark Matter Search (CDMS) strive to discern the kinetic energy of recoiling nuclei resulting from WIMP interactions with terrestrial matter. This is a considerable challenge in which the low (expected) rate of WIMP interactions must be distinguished from an overwhelming rate due to known types of radiation. An incontrovertible positive detection has remained elusive. However, a few experiments have recorded data that appear consistent with a low-mass WIMP. This thesis describes an attempt to probe the favored parameter space. To increase sensitivity to low-mass WIMPs, a low-threshold technique with improved sensitivity to small energy depositions is applied to CDMS shallowsite data. Four germanium and two silicon detectors were operated between December 2001 and June 2002, yielding 118 days of exposure. By sacrificing some of the CDMS detectors’ ability to discriminate signal from background, energy thresholds of ~1 and ~2 keV were achieved for three of the germanium and both silicon detectors, respectively. A large number of WIMP candidate events are observed, most of which can be accounted for by misidentification of background sources. No conclusive evidence for a low-mass WIMP signal is found. The observed event rates are used to set upper limits on the WIMPnucleon scattering cross section as a function of WIMP mass. Interesting parameter space is excluded for WIMPs with masses below ~9GeV/c2. Under standard assumptions, the parameter space favored by interpretations of other experiments

  11. Search for WIMP dark matter in VBF- and monojet topologies with the ATLAS experiment at 13 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Geisler, Manuel Patrice [Kirchhoff-Institut fuer Physik, Heidelberg (Germany)

    2016-07-01

    The cosmological evidence for Dark Matter is strong, however the nature of Dark Matter is still unknown and it has yet to be detected directly. The presented search with the ATLAS experiment at the LHC, CERN, focuses on WIMP (weakly interacting massive particles) Dark Matter candidates. Different kinds of final states are investigated: both so-called monojets and final states with at least two jets of high transverse momenta and a significant amount of missing transverse momentum. The inclusion of the two-jet selection criteria enhances the sensitivity of this search to vector boson fusion topologies. Furthermore, the selection criteria are optimized in order to suppress background processes that mimic the production of Dark Matter particles. In this talk, further techniques of the search are presented, and aspects of the analysis performed with the 2015 dataset of proton-proton collision at √(s)=13 TeV are covered.

  12. Limits on Active to Sterile Neutrino Oscillations from Disappearance Searches in the MINOS, Daya Bay, and Bugey-3 Experiments

    Science.gov (United States)

    Adamson, P.; An, F. P.; Anghel, I.; Aurisano, A.; Balantekin, A. B.; Band, H. R.; Barr, G.; Bishai, M.; Blake, A.; Blyth, S.; Bock, G. J.; Bogert, D.; Cao, D.; Cao, G. F.; Cao, J.; Cao, S. V.; Carroll, T. J.; Castromonte, C. M.; Cen, W. R.; Chan, Y. L.; Chang, J. F.; Chang, L. C.; Chang, Y.; Chen, H. S.; Chen, Q. Y.; Chen, R.; Chen, S. M.; Chen, Y.; Chen, Y. X.; Cheng, J.; Cheng, J.-H.; Cheng, Y. P.; Cheng, Z. K.; Cherwinka, J. J.; Childress, S.; Chu, M. C.; Chukanov, A.; Coelho, J. A. B.; Corwin, L.; Cronin-Hennessy, D.; Cummings, J. P.; de Arcos, J.; De Rijck, S.; Deng, Z. Y.; Devan, A. V.; Devenish, N. E.; Ding, X. F.; Ding, Y. Y.; Diwan, M. V.; Dolgareva, M.; Dove, J.; Dwyer, D. A.; Edwards, W. R.; Escobar, C. O.; Evans, J. J.; Falk, E.; Feldman, G. J.; Flanagan, W.; Frohne, M. V.; Gabrielyan, M.; Gallagher, H. R.; Germani, S.; Gill, R.; Gomes, R. A.; Gonchar, M.; Gong, G. H.; Gong, H.; Goodman, M. C.; Gouffon, P.; Graf, N.; Gran, R.; Grassi, M.; Grzelak, K.; Gu, W. Q.; Guan, M. Y.; Guo, L.; Guo, R. P.; Guo, X. H.; Guo, Z.; Habig, A.; Hackenburg, R. W.; Hahn, S. R.; Han, R.; Hans, S.; Hartnell, J.; Hatcher, R.; He, M.; Heeger, K. M.; Heng, Y. K.; Higuera, A.; Holin, A.; Hor, Y. K.; Hsiung, Y. B.; Hu, B. Z.; Hu, T.; Hu, W.; Huang, E. C.; Huang, H. X.; Huang, J.; Huang, X. T.; Huber, P.; Huo, W.; Hussain, G.; Hylen, J.; Irwin, G. M.; Isvan, Z.; Jaffe, D. E.; Jaffke, P.; James, C.; Jen, K. L.; Jensen, D.; Jetter, S.; Ji, X. L.; Ji, X. P.; Jiao, J. B.; Johnson, R. A.; de Jong, J. K.; Joshi, J.; Kafka, T.; Kang, L.; Kasahara, S. M. S.; Kettell, S. H.; Kohn, S.; Koizumi, G.; Kordosky, M.; Kramer, M.; Kreymer, A.; Kwan, K. K.; Kwok, M. W.; Kwok, T.; Lang, K.; Langford, T. J.; Lau, K.; Lebanowski, L.; Lee, J.; Lee, J. H. C.; Lei, R. T.; Leitner, R.; Leung, J. K. C.; Li, C.; Li, D. J.; Li, F.; Li, G. S.; Li, Q. J.; Li, S.; Li, S. C.; Li, W. D.; Li, X. N.; Li, Y. F.; Li, Z. B.; Liang, H.; Lin, C. J.; Lin, G. L.; Lin, S.; Lin, S. K.; Lin, Y.-C.; Ling, J. J.; Link, J. M.; Litchfield, P. J.; Littenberg, L.; Littlejohn, B. R.; Liu, D. W.; Liu, J. C.; Liu, J. L.; Loh, C. W.; Lu, C.; Lu, H. Q.; Lu, J. S.; Lucas, P.; Luk, K. B.; Lv, Z.; Ma, Q. M.; Ma, X. B.; Ma, X. Y.; Ma, Y. Q.; Malyshkin, Y.; Mann, W. A.; Marshak, M. L.; Martinez Caicedo, D. A.; Mayer, N.; McDonald, K. T.; McGivern, C.; McKeown, R. D.; Medeiros, M. M.; Mehdiyev, R.; Meier, J. R.; Messier, M. D.; Miller, W. H.; Mishra, S. R.; Mitchell, I.; Mooney, M.; Moore, C. D.; Mualem, L.; Musser, J.; Nakajima, Y.; Naples, D.; Napolitano, J.; Naumov, D.; Naumova, E.; Nelson, J. K.; Newman, H. B.; Ngai, H. Y.; Nichol, R. J.; Ning, Z.; Nowak, J. A.; O'Connor, J.; Ochoa-Ricoux, J. P.; Olshevskiy, A.; Orchanian, M.; Pahlka, R. B.; Paley, J.; Pan, H.-R.; Park, J.; Patterson, R. B.; Patton, S.; Pawloski, G.; Pec, V.; Peng, J. C.; Perch, A.; Pfützner, M. M.; Phan, D. D.; Phan-Budd, S.; Pinsky, L.; Plunkett, R. K.; Poonthottathil, N.; Pun, C. S. J.; Qi, F. Z.; Qi, M.; Qian, X.; Qiu, X.; Radovic, A.; Raper, N.; Rebel, B.; Ren, J.; Rosenfeld, C.; Rosero, R.; Roskovec, B.; Ruan, X. C.; Rubin, H. A.; Sail, P.; Sanchez, M. C.; Schneps, J.; Schreckenberger, A.; Schreiner, P.; Sharma, R.; Moed Sher, S.; Sousa, A.; Steiner, H.; Sun, G. X.; Sun, J. L.; Tagg, N.; Talaga, R. L.; Tang, W.; Taychenachev, D.; Thomas, J.; Thomson, M. A.; Tian, X.; Timmons, A.; Todd, J.; Tognini, S. C.; Toner, R.; Torretta, D.; Treskov, K.; Tsang, K. V.; Tull, C. E.; Tzanakos, G.; Urheim, J.; Vahle, P.; Viaux, N.; Viren, B.; Vorobel, V.; Wang, C. H.; Wang, M.; Wang, N. Y.; Wang, R. G.; Wang, W.; Wang, X.; Wang, Y. F.; Wang, Z.; Wang, Z. M.; Webb, R. C.; Weber, A.; Wei, H. Y.; Wen, L. J.; Whisnant, K.; White, C.; Whitehead, L.; Whitehead, L. H.; Wise, T.; Wojcicki, S. G.; Wong, H. L. H.; Wong, S. C. F.; Worcester, E.; Wu, C.-H.; Wu, Q.; Wu, W. J.; Xia, D. M.; Xia, J. K.; Xing, Z. Z.; Xu, J. L.; Xu, J. Y.; Xu, Y.; Xue, T.; Yang, C. G.; Yang, H.; Yang, L.; Yang, M. S.; Yang, M. T.; Ye, M.; Ye, Z.; Yeh, M.; Young, B. L.; Yu, Z. Y.; Zeng, S.; Zhan, L.; Zhang, C.; Zhang, H. H.; Zhang, J. W.; Zhang, Q. M.; Zhang, X. T.; Zhang, Y. M.; Zhang, Y. X.; Zhang, Z. J.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, J.; Zhao, Q. W.; Zhao, Y. B.; Zhong, W. L.; Zhou, L.; Zhou, N.; Zhuang, H. L.; Zou, J. H.; Daya Bay Collaboration

    2016-10-01

    Searches for a light sterile neutrino have been performed independently by the MINOS and the Daya Bay experiments using the muon (anti)neutrino and electron antineutrino disappearance channels, respectively. In this Letter, results from both experiments are combined with those from the Bugey-3 reactor neutrino experiment to constrain oscillations into light sterile neutrinos. The three experiments are sensitive to complementary regions of parameter space, enabling the combined analysis to probe regions allowed by the Liquid Scintillator Neutrino Detector (LSND) and MiniBooNE experiments in a minimally extended four-neutrino flavor framework. Stringent limits on sin22 θμ e are set over 6 orders of magnitude in the sterile mass-squared splitting Δ m412. The sterile-neutrino mixing phase space allowed by the LSND and MiniBooNE experiments is excluded for Δ m412<0.8 eV2 at 95 % CLs .

  13. Limits on Active to Sterile Neutrino Oscillations from Disappearance Searches in the MINOS, Daya Bay, and Bugey-3 Experiments

    CERN Document Server

    Bay, The Daya; Adamson, P; An, F P; Anghel, I; Aurisano, A; Balantekin, A B; Band, H R; Barr, G; Bishai, M; Blake, A; Bock, S Blyth G J; Bogert, D; Cao, D; Cao, G F; Cao, J; Cao, S V; Carroll, T J; Castromonte, C M; Cen, W R; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chen, H S; Chen, Q Y; Chen, R; Chen, S M; Chen, Y; Chen, Y X; Cheng, J; Cheng, J -H; Chen, Y P; Cheng, Z K; Cherwinka, J J; Childress, S; Chu, M C; Chukanov, A; Coelho, J A B; Corwin, L; Cronin-Hennessy, D; Cummings, J P; de Arcos, J; De Rijck, S; Deng, Z Y; Devan, A V; Devenish, N E; Ding, X F; Ding, Y Y; Diwan, M V; Dolgareva, M; Dove, J; Dwyer, D A; Edwards, W R; Escobar, C O; Evans, J J; Falk, E; Feldman, G J; Flanagan, W; Frohne, M V; Gabrielyan, M; Gallagher, H R; Germani, S; Gill, R; Gomes, R A; Gonchar, M; Gong, G H; Gong, H; Goodman, M C; Gouffon, P; Graf, N; Gran, R; Grassi, M; Grzelak, K; Gu, W Q; Guan, M Y; Guo, L; Guo, R P; Guo, X H; Guo, Z; Habig, A; Hackenburg, R W; Hahn, S R; Han, R; Hans, S; Hartnell, J; Hatcher, R; He, M; Heeger, K M; Heng, Y K; Higuera, A; Holin, A; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, T; Hu, W; Huang, E C; Huang, H X; Huang, J; Huang, X T; Huber, P; Huo, W; Hussain, G; Hylen, J; Irwin, G M; Isvan, Z; Jaffe, D E; Jaffke, P; James, C; Jen, K L; Jensen, D; Jetter, S; Ji, X L; Ji, X P; Jiao, J B; Johnson, R A; de Jong, J K; Joshi, J; Kafka, T; Kang, L; Kasahara, S M S; Kettell, S H; Kohn, S; Koizumi, G; Kordosky, M; Kramer, M; Kreymer, A; Kwan, 1 K K; Kwok, M W; Kwok, T; Lang, K; Langford, T J; Lau, K; Lebanowski, L; Lee, J; Lee, J H C; Lei, R T; Leitner, R; Leung, J K C; Li, C; Li, D J; Li, F; Li, G S; Li, Q J; Li, S; Li, S C; Li, W D; Li, X N; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, S; Lin, S K; Lin, Y -C; Link, J J Ling J M; Litchfield, P J; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, J C; Liu, J L; Loh, C W; Lu, C; Lu, H Q; Lu, J S; Lucas, P; Luk, K B; Lv, Z; Ma, Q M; Ma, X B; Ma, X Y; Ma, Y Q; Malyshkin, Y; Mann, W A; Marshak, M L; Caicedo, D A Martinez; Mayer, N; McDonald, K T; McGivern, C; McKeown, R D; Medeiros, M M; Mehdiyev, R; Meier, J R; Messier, M D; Miller, W H; Mishra, S R; Mitchell, I; Mooney, M; Moore, C D; Mualem, L; Musser, J; Nakajima, Y; Naples, D; Napolitano, J; Naumov, D; Naumova, E; Nelson, J K; Newman, H B; Ngai, H Y; Nichol, R J; Ning, Z; Nowak, A; O'Connor, J; Ochoa-Ricoux, J P; Olshevskiy, A; Orchanian, M; R.,; Pahlka, R B; Paley, J; Pan, H -R; Park, J; Patterson, R B; Patton, S; Pawloski, G; Pec, V; Peng, J C; Perch, A; Pfutzner, M M; Phan, D D; Phan-Budd, S; Pinsky, L; Plunkett, R K; Poonthottathil, N; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Qiu, X; Radovic, A; Raper, N; Rebel, B; Ren, J; Rosenfeld, C; Rosero, R; Roskovec, B; Ruan, X C; Rubin, H A; Sail, P; Sanchez, M C; Schneps, J; Schreckenberger, A; Schreiner, P; Sharma, R; Sher, S Moed; Sousa, A; Steiner, H; Sun, G X; Sun, J L; Tagg, N; Talaga, R L; Tang, W; Taychenachev, D; Thomas, J; Thomson, M A; Timmons, X Tian A; Todd, J; Tognini, S C; Toner, R; Torretta, D; Treskov, K; Tsang, K V; Tull, C E; Tzanakos, G; Urheim, J; Vahle, P; Viaux, N; Viren, B; Vorobel, V; Wang, C H; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, X; Wang, Y F; Wang, Z; Wang, Z M; Webb, R C; Weber, A; Wei, H Y; Wen, L J; Whisnant, K; White, C; Whitehead, L Whitehead L H; Wise, T; Wojcicki, S G; Wong, H L H; Wong, S C F; Worcester, E; Wu, C -H; Wu, Q; Wu, W J; Xia, D M; Xia, J K; Xing, Z Z; Xu, J L; Xu, J Y; Xu, Y; Xue, T; Yang, C G; Yang, H; Yang, L; Yang, M S; Yang, M T; Ye., M; Ye, Z; Yeh, M; Young, B L; Yu, Z Y; Zeng, S; Zhang, L ZhanC; Zhang, H H; Zhang, J W; Zhang, Q M; Zhang, X T; Zhang, Y M; Zhang, Y X; Zhang, Z J; Zhang, Z P; Zhang, Z Y; Zhao, J; Zhao, Q W; Zhao, Y B; Zhong, W L; Zhou, L; Zhou, N; Zhuang, H L; Zou, J H

    2016-01-01

    Searches for a light sterile neutrino have been independently performed by the MINOS and the Daya Bay experiments using the muon (anti)neutrino and electron antineutrino disappearance channels, respectively. In this Letter, results from both experiments are combined with those from the Bugey-3 reactor neutrino experiment to constrain oscillations into light sterile neutrinos. The three experiments are sensitive to complementary regions of parameter space, enabling the combined analysis to probe regions allowed by the LSND and MiniBooNE experiments in a minimally extended four-neutrino flavor framework. Stringent limits on $\\sin^2 2\\theta_{\\mu e}$ are set over six orders of magnitude in the sterile mass-squared splitting $\\Delta m^2_{41}$. The sterile-neutrino mixing phase space allowed by the LSND and MiniBooNE experiments is excluded for $\\Delta m^2_{41} < 0.8$ eV$^2$ at 95\\% C.L.

  14. A search for new heavy particles in events with highly ionising, short tracks at the CMS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Lenz, Teresa

    2016-06-15

    The main focus of the CMS experiment at the Large Hadron Collider (LHC) is to search for physics beyond the Standard Model and to measure Standard Model parameters. For both purposes it is essential to determine important performance parameters of the CMS detector. The here presented thesis contributes in a twofold way to the physics program of CMS. In the first part of this thesis, a search for physics beyond the Standard Model is presented. It is motivated by supersymmetric models with nearly mass-degenerate lightest neutralinos and lightest charginos. The small mass gap between chargino and neutralino can lead to long lifetimes of the chargino due to phase space suppression. Thus, the chargino can reach the tracking system before its decay. The here presented search targets chargino lifetimes of cτ ∼ 1-30 cm where most of the charginos decay in the first layers of the tracker. This search aims at increasing the search sensitivity of existing searches with respect to these models in a twofold way: first, the inclusion of tracks down to three measurements in the tracking system, and second, the discrimination against Standard Model background by the energy loss per path length. The search is performed on 19.7 fb{sup -1} of data recorded at the CMS experiment at a centre-of-mass energy of 8 TeV. No excess above the Standard Model expectation is found and the supersymmetric parameter space is constrained. The search can exclude supersymmetric models with chargino masses of 100 GeV down to lifetimes of cτ=2 cm and models with masses of 500 GeV down to lifetimes of cτ=70 cm. Current limits are confirmed and improvements of the order of 10-40 GeV in chargino mass are achieved. In the second part of the thesis, a measurement of the jet transverse-momentum resolution at 8 TeV at the CMS experiment is presented. In order to exploit the good energy resolution of the electromagnetic calorimeter of the CMS detector, the measurement is performed using γ+jet events. Due

  15. Searches For New Physics Using High Mass Dimuons At The Cdf Ii Experiment

    CERN Document Server

    Karagoz-Unel, M

    2004-01-01

    The Collider Detector at Fermilab collected approximately 200 pb −1 of Tevatron pp¯ collision data at s = 1.96 TeV between spring 2002 and fall 2003. We present results for searches for new physics in the dimuon final state using these data. The searches include heavy neutral particles predicted within extended gauge groups (various Z's), Technicolor (vector mesons), R- parity violating Supersymmetry (scalar neutrino), and warped extra dimensions (Randall-Sundrum gravitons). We present 95% Confidence Level (C.L.) upper limits on the production cross section times the branching ratio of new particles as a function of the dimuon invariant mass and place 95% C.L. lower mass bounds on the particles. Current limits exceed published limits of previous direct searches in the dimuon channel. We also pioneered search strategies and exploration of some models. Limit results from the electron and muon combined channels are also presented.

  16. The Use of Drugs in the Search for a Human Aphrodisiac Experience

    Science.gov (United States)

    Edwards, Ralph

    1971-01-01

    This article delineates man's search for sexual pleasure through the aid of drugs and other substances. While myths prevail that drugs create the sexual libertine spirit, scientific evidence indicates that no known drug serves as an aphrodisiac. (Author)

  17. Searches for exotic heavy quarks decaying into a W-Boson and a b-Quark with the ATLAS experiment

    CERN Document Server

    Nektarijevic, Snezana

    In this thesis, searches for two hypothetical heavy quarks are presented: the fourth Standard Model generation up-type quark t’, and the vector-like quark T, predicted by the new physics models involving extra dimensions or a composite Higgs boson. Both searches assume pair production of the heavy quarks decaying to a W-boson and a b-quark, and are performed in final states with one electron or muon, at least three jets, and significant missing transverse energy. The first search employs the kinematic fitting of the reconstructed quark mass, while the second relies on the artificial neural network method. In both searches no excess of data over the Standard Model expectation is observed, resulting in observed lower bounds on the quark masses of mt’>404 GeV and mT>618 GeV. Both searches are based on proton-proton collision data at 7 TeV centre-of-mass energy collected by the ATLAS experiment at CERN’s Large Hadron Collider in 2011.

  18. Search for Electroweak Single-Top Quark Production with the CDF II Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Buehler, Matthias; /Karlsruhe U., EKP

    2006-08-01

    The CDF II experiment and the Tevatron proton-antiproton collider are parts of the Fermi National Laboratories (Fermilab). The Fermilab is located in the vicinity of Chicago, USA. Today, the Tevatron is the only collider which is able to produce the heaviest known elementary particle, the top quark. The top quark was discovered at the Tevatron by the CDF and the D0 collaborations in 1995 [1]. So far, all the top quarks found are produced via the strong interaction as top-antitop pairs. The Standard Model of elementary particle physics also predicts single-top quark production via the electroweak interaction. This production mode has not yet been observed. The CDF and the D0 collaborations have set upper limits on the cross section for that process in Run I [2, 3] and improved those results in Run II [4, 5]. Single-top quark production is one of the major interests in Run II of the Tevatron as it offers several ways to test the Standard Model and to search for potential physics beyond the Standard Model. The measurement of the cross section of singly produced top quarks via the electroweak interaction offers the possibility to determine the Cabbibo-Kobayashi-Maskawa (CKM) matrix element V{sub tb} directly. The CKM matrix defines the transformation from the eigenstates of the electroweak interactions to the mass eigenstates of the quarks. V{sub tb} gives the strength of the coupling at the Wtb vertex. The single-top quark is produced at this vertex and therefore the cross section of the single-top quark production is directly proportional to |V{sub tb}|{sup 2}. In the Standard Model, three generations of quarks and the unitarity of the CKM matrix are predicted. This leads to V{sub tb} {approx} 1. Up to now, there is no possibility to measure V{sub tb} without using the assumption that there are a certain number of quark generations. Since the measurement of the cross section of single-top quark production is independent of this assumption it could verify another

  19. Information overload or search-amplified risk? Set size and order effects on decisions from experience.

    Science.gov (United States)

    Hills, Thomas T; Noguchi, Takao; Gibbert, Michael

    2013-10-01

    How do changes in choice-set size influence information search and subsequent decisions? Moreover, does information overload influence information processing with larger choice sets? We investigated these questions by letting people freely explore sets of gambles before choosing one of them, with the choice sets either increasing or decreasing in number for each participant (from two to 32 gambles). Set size influenced information search, with participants taking more samples overall, but sampling a smaller proportion of gambles and taking fewer samples per gamble, when set sizes were larger. The order of choice sets also influenced search, with participants sampling from more gambles and taking more samples overall if they started with smaller as opposed to larger choice sets. Inconsistent with information overload, information processing appeared consistent across set sizes and choice order conditions, reliably favoring gambles with higher sample means. Despite the lack of evidence for information overload, changes in information search did lead to systematic changes in choice: People who started with smaller choice sets were more likely to choose gambles with the highest expected values, but only for small set sizes. For large set sizes, the increase in total samples increased the likelihood of encountering rare events at the same time that the reduction in samples per gamble amplified the effect of these rare events when they occurred-what we call search-amplified risk. This led to riskier choices for individuals whose choices most closely followed the sample mean.

  20. Searching for What I Want

    DEFF Research Database (Denmark)

    Liu, Fei; Xiao, Bo Sophia; Lim, Eric

    2016-01-01

    of anticipa-tory system as our theoretical foundation to articulate the relationships between two salient types of search controls, namely search anticipation and search efficiency. We empirically validate our re-search model by conducting a field survey with 77 university students on an online restaurant...... review website that is modelled after its actual counterpart and populated with real restaurant review data. Findings from this study suggest that both search determination control and search manipulation con-trol enhance search result anticipation, which in turn improves search efficiency. Theoretical...

  1. The impact of search engine selection and sorting criteria on vaccination beliefs and attitudes: two experiments manipulating Google output.

    Science.gov (United States)

    Allam, Ahmed; Schulz, Peter Johannes; Nakamoto, Kent

    2014-04-02

    During the past 2 decades, the Internet has evolved to become a necessity in our daily lives. The selection and sorting algorithms of search engines exert tremendous influence over the global spread of information and other communication processes. This study is concerned with demonstrating the influence of selection and sorting/ranking criteria operating in search engines on users' knowledge, beliefs, and attitudes of websites about vaccination. In particular, it is to compare the effects of search engines that deliver websites emphasizing on the pro side of vaccination with those focusing on the con side and with normal Google as a control group. We conducted 2 online experiments using manipulated search engines. A pilot study was to verify the existence of dangerous health literacy in connection with searching and using health information on the Internet by exploring the effect of 2 manipulated search engines that yielded either pro or con vaccination sites only, with a group receiving normal Google as control. A pre-post test design was used; participants were American marketing students enrolled in a study-abroad program in Lugano, Switzerland. The second experiment manipulated the search engine by applying different ratios of con versus pro vaccination webpages displayed in the search results. Participants were recruited from Amazon's Mechanical Turk platform where it was published as a human intelligence task (HIT). Both experiments showed knowledge highest in the group offered only pro vaccination sites (Z=-2.088, P=.03; Kruskal-Wallis H test [H₅]=11.30, P=.04). They acknowledged the importance/benefits (Z=-2.326, P=.02; H5=11.34, P=.04) and effectiveness (Z=-2.230, P=.03) of vaccination more, whereas groups offered antivaccination sites only showed increased concern about effects (Z=-2.582, P=.01; H₅=16.88, P=.005) and harmful health outcomes (Z=-2.200, P=.02) of vaccination. Normal Google users perceived information quality to be positive despite a

  2. Search for stable mutli-charged particles with the ATLAS experiment

    Directory of Open Access Journals (Sweden)

    Zimmermann Simone

    2013-11-01

    Full Text Available A search for long-lived, multi-charged particles is performed using the ATLAS detector. We examine pp collision-data taken during the 2011 LHC running, corresponding to an integrated luminosity of 4.4 fb−1. A search is made for charged particle tracks exhibiting anomalously high ionization consistent with stable massive particles with charges from |q| = 2e to |q| = 6e. For this search new variables of specific energy loss per path length (dE/dx are developed and used in the candidate selection. No excess is observed with respect to the prediction of Standard Model processes. The 95% CL cross-section limits are interpreted as lower mass limits of 420-490 GeV for a simplified Drell-Yan production model.

  3. Search for a new gauge boson in the $A'$ Experiment (APEX)

    CERN Document Server

    Abrahamyan, S; Allada, K; Anez, D; Averett, T; Barbieri, A; Bartlett, K; Beacham, J; Bono, J; Boyce, J R; Brindza, P; Camsonne, A; Cranmer, K; Dalton, M M; deJager, C W; Donaghy, J; Essig, R; Field, C; Folts, E; Gasparian, A; Goeckner-Wald, N; Gomez, J; Graham, M; Hansen, J -O; Higinbotham, D W; Holmstrom, T; Huang, J; Iqbal, S; Jaros, J; Jensen, E; Kelleher, A; Khandaker, M; LeRose, J J; Lindgren, R; Liyanage, N; Long, E; Mammei, J; Markowitz, P; Maruyama, T; Maxwell, V; Mayilyan, S; McDonald, J; Michaels, R; Moffeit, K; Nelyubin, V; Odian, A; Oriunno, M; Partridge, R; Paolone, M; Piasetzky, E; Pomerantz, I; Qiang, Y; Riordan, S; Roblin, Y; Sawatzky, B; Schuster, P; Segal, J; Selvy, L; Shahinyan, A; Subedi, R; Sulkosky, V; Stepanyan, S; Toro, N; Walz, D; Wojtsekhowski, B; Zhang, J

    2011-01-01

    We present a search at Jefferson Laboratory for new forces mediated by sub-GeV vector bosons with weak coupling $\\alpha'$ to electrons. Such a particle $A'$ can be produced in electron-nucleus fixed-target scattering and then decay to an $e^+e^-$ pair, producing a narrow resonance in the QED trident spectrum. Using APEX test run data, we searched in the mass range 175--250 MeV, found no evidence for an $A'\\to e^+e^-$ reaction, and set an upper limit of $\\alpha'/\\alpha \\simeq 10^{-6}$. Our findings demonstrate that fixed-target searches can explore a new, wide, and important range of masses and couplings for sub-GeV forces.

  4. Search for WIMP-Induced Annual Modulation with the CUORE-0 Experiment

    Science.gov (United States)

    Lim, Kyungeun; Cuore Collaboration

    2016-09-01

    CUORE-0 was a cryogenic detector that uses an array of tellurium dioxide bolometers with the primary physics goal of searching for neutrinoless double-beta decay of Te-130. CUORE-0 was assembled using new low-background techniques developed for CUORE, which will consist of 19 CUORE-0-like arrays. The first results on the search for neutrinoless double-beta decay with CUORE-0 combined with Cuoricinio, a predecessor to CUORE-0, set the most stringent limit on the half-life of Te-130. Successful background mitigation, along with continuous data acquisition make CUORE-0 also suitable for other low-energy, rare event searches such as dark matter. In this talk, I will present the status and results of the low-energy analysis of CUORE-0. DOE-NP.

  5. Searches for new physics in the top quark samples at the CDF experiment

    Energy Technology Data Exchange (ETDEWEB)

    Scodellaro, Luca; /Cantabria Inst. of Phys.

    2007-10-01

    Twelve years after the discovery of the top quark at Fermilab's Tevatron, they are now finally beginning to shed light on this peculiarily massive quark. With 1-1.7 fb{sup -1} of integrated luminosity collected by the CDF detector, they are able to probe the knowledge of the top quark physics, and to search for signals of physics beyond the Standard Model. In this paper, they present results of measurements of top quark properties, as well as tests for the production mechanism of the top quark. They also describe CDF latest searches for beyond Standard Model couplings of the top quark. Finally, they present the most recent searches for direct production of new particles in the collected data samples.

  6. Searches for squark and gluino production in hadronic final states with the ATLAS experiment

    CERN Document Server

    Besjes, Geert-Jan; The ATLAS collaboration

    2016-01-01

    Weak scale supersymmetry is one of the best motivated and studied extensions of the Standard Model. The recent increase in the center of mass energy of the proton-proton collisions gives a unique opportunity to extend the sensitivity to production of supersymmetric particles at the Large Hadron Collider. This talk summarises recent ATLAS results on searches for supersymmetric squarks and gluinos, including third generation squarks produced directly or via decay of gluinos. The searches involved final states containing jets (possibly identified as coming from $b$ quarks), missing transverse momentum and no leptons.

  7. Search for Lepton Flavor Violation in Z and Higgs decays with the CMS Experiment

    CERN Document Server

    Nehrkorn, Alexander

    2016-01-01

    The standard model of particle physics explicitly conserves lepton flavor in particle interactions in spite of the absence of an underlying symmetry. The observation of neutrino oscillation proves neutral lepton flavor violation (LFV) and thus motivates a search for violations in charged lepton interactions. Here, searches for LFV performed by the CMS collaboration in leptonic decays of the Z and Higgs boson are presented. The data analyzed contains $19.7\\,\\mathrm{fb}^{-1}$\\, ($2.3\\,\\mathrm{fb}^{-1}$) of proton-proton collisions at $\\sqrt{s}=8\\,(13)\\,\\mathrm{TeV}$ delivered by the LHC during 2012 (2015).

  8. Search for R-parity violating supersymmetry and long-lived particles at the ATLAS experiment

    CERN Document Server

    Chitan, A; The ATLAS collaboration

    2014-01-01

    Admission of R-parity violation introduces new signatures to the search for supersymmetry at the LHC. Strongly interacting resonances may decay to jets, sleptons may decay via lepton-flavour violating processes and lightest supersymmetric particles may decay into many leptons with or without missing transverse momentum. Several supersymmetric models also predict massive long-lived supersymmetric particles. Such particles may be detected through abnormal specific energy loss, appearing or disappearing tracks, displaced vertices, long time-of-flight or late calorimetric energy deposits. The talk presents recent results from searches supersymmetry in resonance production, R-parity violating signatures and events with long-lived particles with the ATLAS detector.

  9. Phase III (and maybe IV of the SIMPLE dark matter search experiment at the LSBB

    Directory of Open Access Journals (Sweden)

    Girard T.A.

    2014-01-01

    Full Text Available with the recent conclusion of Phase II, SIMPLE has ended its use of Superheated Droplet Detectors (SDD in the WIMP search effort. An in-progress Phase III comprises a transition to larger mass bubble chamber technology, using many of the lessons gained from the previous phase since the underlying physics is identical. We describe the progress of the activities, to include several ∼1 kg prototype chambers, each 4× the total Phase II active mass, which are undergoing testing, prior to a rescaling to a 50 kg capacity within a Phase IV modular 1 ton detector for a definitive astroparticle search effort.

  10. Search for ttH production (H-> bb) at the ATLAS experiment

    CERN Document Server

    ATLAS Collaboration; The ATLAS collaboration

    2017-01-01

    Searching for the production of Higgs boson in association with a pair of top quarks would allow a direct measurement of the top quark Yukawa coupling and will provide an important test of the Higgs mechanism within the Standard Model. A search for this process is presented using proton- proton collisions at sqrt(s) = 13 TeV, collected by the ATLAS detector in both 2015 and 2016. Higgs boson decaying to two b quarks, and top pair decaying in semi-leptonic or diletonic are considered.

  11. The GlueX experiment: Search for gluonic excitations via photoproduction at Jefferson Lab

    Energy Technology Data Exchange (ETDEWEB)

    Eugenio, Paul [Florida State U.

    2013-07-01

    Studies of meson spectra via strong decays provide insight regarding QCD at the confinement scale. These studies have led to phenomenological models for QCD such as the constituent quark model. However, QCD allows for a much richer spectrum of meson states which include extra states such as exotics, hybrids, multi-quarks, and glueballs. First discussion of the status of exotic meson searches is given followed by an overview of the progress at Jefferson Lab to double the energy of the machine to 12 GeV, which will allow us to access photoproduction of mesons in search for gluonic excited states.

  12. A Search of Low-Mass WIMPs with p-type Point Contact Germanium Detector in the CDEX-1 Experiment

    CERN Document Server

    Zhao, W; Kang, K J; Cheng, J P; Li, Y J; Wong, H T; Lin, S T; Chang, J P; Chen, J H; Chen, Q H; Chen, Y H; Deng, Z; Du, Q; Gong, H; Hao, X Q; He, H J; He, Q J; Huang, H X; Huang, T R; Jiang, H; Li, H B; Li, J; Li, J M; Li, X; Li, X Y; Li, Y L; Lin, F K; Liu, S K; Lü, L C; Ma, H; Ma, J L; Mao, S J; Qin, J Q; Ren, J; Ruan, X C; Sharma, V; Shen, M B; Singh, L; Singh, M K; Soma, A K; Su, J; Tang, C J; Wang, J M; Wang, L; Wang, Q; Wu, S Y; Wu, Y C; Xianyu, Z Z; Xiao, R Q; Xing, H Y; Xu, F Z; Xu, Y; Xu, X J; Xue, T; Yang, L T; Yang, S W; Yi, N; Yu, C X; Yu, H; Yu, X Z; Zeng, M; Zeng, X H; Zeng, Z; Zhang, L; Zhang, Y H; Zhao, M G; Zhou, Z Y; Zhu, J J; Zhu, W B; Zhu, X Z; Zhu, Z H

    2016-01-01

    The CDEX-1 experiment conducted a search of low-mass (< 10 GeV/c2) Weakly Interacting Massive Particles (WIMPs) dark matter at the China Jinping Underground Laboratory using a p-type point-contact germanium detector with a fiducial mass of 915 g at a physics analysis threshold of 475 eVee. We report the hardware set-up, detector characterization, data acquisition and analysis procedures of this experiment. No excess of unidentified events are observed after subtraction of known background. Using 335.6 kg-days of data, exclusion constraints on the WIMP-nucleon spin-independent and spin-dependent couplings are derived.

  13. Search for Production of SUSY Particles Produced via Electroweak Interactions with the ATLAS Experiment

    CERN Document Server

    Shehu, Ciwake Yusufu; The ATLAS collaboration

    2016-01-01

    Many supersymmetry models feature gauginos and also sleptons with masses less than a few hundred GeV. These can give rise to direct pair production rates at the LHC that can be observed in the data sample recorded by the ATLAS detector. The talk summarises the status of searches for gaugino and slepton pair production in final states with leptons.

  14. Inclusive searches for squarks and gluinos with the ATLAS experiment at LHC

    CERN Document Server

    Maurer, Julien; The ATLAS collaboration

    2015-01-01

    This presentation provides an overview of the ATLAS searches for squarks and gluinos with 8 TeV data. Various signatures are analyzed, and exclusion limits are set on multiple SUSY scenarios in the absence of any significant excess in observed data.

  15. Filling the Position of Lead Administrator in Schools of Allied Health: The Experience of Search Committees.

    Science.gov (United States)

    Layman, Elizabeth J.; Bamberg, Richard; Jones, Harold P.

    2002-01-01

    Responses from 20 chairs of allied health dean/director search committees indicated that 55% found filling the position very or moderately easy. Mean time was 6.9 months. Most (65%) new deans/directors had health professions backgrounds; 30% had been assistant deans/directors. With a mean number of 11.7 viable candidates, the applicant pool was…

  16. Operating the GridPix detector in dark matter search experiments

    NARCIS (Netherlands)

    Schön, R.; Alfonsi, M.; Hemink, G.; Decowski, M.P.; van Bakel, N.; van der Graaf, H.

    2013-01-01

    The DARWIN (dark matter WIMP search with noble liquids) design study aims to use liquid argon and liquid xenon targets to look for nuclear recoils due to weakly interacting massive particles (WIMPs). To measure the recoil energy in dual-phase noble gas time projection chambers the combination of sci

  17. Searches for Higgs bosons beyond the Standard Model using the ATLAS experiment

    CERN Document Server

    Ferrari, Arnaud; The ATLAS collaboration

    2015-01-01

    Two searches for additional charged and neutral Higgs bosons, as predicted by Two-Higgs-Doublet Models, are presented. These analyses are based on the 2012 pp collision dataset collected by ATLAS at a center-of-mass energy of 8 TeV. Upper limits are presented, as well as their interpretation in CP-conserving 2HDMs.

  18. Department of Defense Report on Search for Human Radiation Experiment Records, 1944 - 1994, Volume 2

    Science.gov (United States)

    1997-06-01

    radioisotope lymphography. A comparison of stannous phytate and antimony sulfide Addendum to Volume I, Appendix I—Records Search 27 IARMY 1944-1,074...of supraclavicular nodes. Although previously published animal data suggested utility of Tc-99m stannous phytate for lymph-node imaging, Tc99m

  19. Auroral counterpart of magnetic field dipolarizations in Saturn's tail

    Science.gov (United States)

    Jackman, C. M.; Badman, S. V.; Achilleos, N.; Bunce, E. J.; Cowley, S. W. H.; Radioti, A.; Grodent, D.; Dougherty, M. K.; Pryor, W.

    2012-04-01

    Following magnetic reconnection in a planetary magnetotail, newly closed field lines can be rapidly accelerated back towards the planet, becoming "dipolarized" in the process. At Saturn, dipolarizations can be initially identified in magnetometer data by looking for a southward turning of the magnetic field, indicating the transition from a radially stretched configuration to a more dipolar field topology. The highly stretched geometry of the kronian magnetotail lobes gives rise to a tail current which flows eastward (dusk to dawn) in the near equatorial plane across the centre of the tail. During reconnection and associated dipolarization of the field, the inner edge of this tail current can be diverted through the ionosphere, in a situation analogous to the substorm current wedge picture at Earth. We present a picture of the current circuit arising from this tail reconfiguration, and outline the equations which govern the field-current relationship. We show an example of a dipolarization identified in the Cassini magnetometer data and use this formalism to constrain the ionospheric current density that would arise for this example and the implications for auroral electron acceleration in regions of upward directed field-aligned current. We then present a separate example of data from the Cassini UVIS instrument where we observe small 'spots' of auroral emission lying near the main oval; features thought to be associated with dipolarizations in the tail. In the example shown, such auroral spots are the precursor to more intense activity associated with recurrent energisation via particle injections from the tail following reconnection. We conclude that dipolarizations in Saturn's magnetotail have an observable auroral counterpart, opening up the possibility to search for further examples and to use this auroral property as a remote proxy for tail reconnection.

  20. Search for supersymmetry in opposite-sign dilepton final states with the CMS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Mohr, Niklar

    2011-10-11

    A search for physics beyond the standard model in final states with opposite-sign isolated lepton pairs accompanied by hadronic jets and missing transverse energy is presented. This signature is a typical signature in many supersymmetric models. In a study based on simulation the discovery potential and possible parameter extraction of a specific supersymmetric model is evaluated. The search is then performed using hadron-hadron data from the LHC recorded with the CMS detector during 2010, corresponding to an integrated luminosity of 36 pb{sup -1}. No evidence for an anomalous event yield beyond Standard Model expectations is found. An upper limit on the non Standard Model contribution in the signal region is deduced from the experimental results. This limit is interpreted in the constrained minimal supersymmetric model. Additional information is provided to allow testing the exclusion of other specific models of physics beyond the SM.

  1. Inclusive search for boosted Higgs bosons using H$\\rightarrow \\marthrm{b\\bar{b}}$ decays with the CMS experiment

    CERN Document Server

    Vernieri, Caterina

    2017-01-01

    We present the first search for the standard model Higgs boson (H) produced with large transverse momentum (p$_{\\rm T}$) via gluon fusion and decaying to a bottom quark-antiquark pair ($b\\bar{b}$). The search is performed using a data set of pp collisions at $\\sqrt{s}=13$~TeV collected with the CMS experiment at the LHC, corresponding to an integrated luminosity of 35.9~fb$^{-1}$. A highly Lorentz-boosted Higgs boson decaying to $b\\bar{b}$ is reconstructed as a single, large radius jet and is identified using jet substructure and dedicated b tagging techniques. The method is validated with the first observation of the Z$\\to b\\bar{b}$ process in the single-jet topology, with a local significance of 1.5 standard deviations (0.7 expected).

  2. Dark Matter searches with Mono-X signatures at the ATLAS experiment

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00377126; The ATLAS collaboration

    2016-01-01

    At the LHC dark matter particles can be produced in association with Standard Model particles coming from initial state radiation. Searches for such processes using events with jets, photons or massive gauge bosons recoiling against large missing transverse momentum in ATLAS at 13 TeV are presented. These ``mono-X'' signatures provide powerful probes to dark matter production at the LHC, allowing for the interpretation of results in terms of simplified models with pair production of WIMPs.

  3. Searches for Vector-Like Quarks at 13 TeV at the ATLAS Experiment

    CERN Document Server

    Nackenhorst, Olaf; The ATLAS collaboration

    2017-01-01

    Vector like quarks appear in many theories beyond the Standard Model as a way to cancel the mass divergence for the Higgs boson. The current status of the ATLAS searches for the production of vector like quarks will be reviewed for proton-proton collisions at 13 TeV. This presentation will address the analysis techniques, in particular the selection criteria, the background modeling and the related experimental uncertainties.

  4. A Search for Higgs Bosons in Final States with Multiple Tau Leptons at the DØ Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Suter, Louise [Univ. of Manchester (United Kingdom)

    2012-09-01

    Two searches for the production of Higgs bosons decaying into τ and μ leptons, using data collected with the DØ detector at the Fermilab Tevatron p$\\bar{p}$ collider, are presented. A search for the pair production of doubly charged Higgs bosons in the process q$\\bar{q}$ → H++H--, where H ±± decays to ττ , μμ or τμ lepton pairs, with an integrated luminosity of up to L = 7:0 fb-1, is presented. No signi cant excess of data over the expected SM background is observed and the results are used to set 95% C.L. limits on the pair production cross section of doubly charged Higgs bosons in the range 90 < MH±± < 200 GeV. A second search for the production of the Standard Model Higgs boson in the nal state ττμ +X is presented, using an integrated luminosity of L = 8:6 fb-1. Again no signi cant excess of data is observed over the background expectation and 95% C.L. limits are set on the observed cross section relative to the Standard Model prediction, in the range 100 < MH < 200 GeV.

  5. The Hunt for a Counterpart to GW150914

    Science.gov (United States)

    Kohler, Susanna

    2016-07-01

    binaries involving neutron stars, they set up a notification system to be able to quickly alert electromagnetic observatories of a gravitational-wave detection. Those observatories would then be able to follow up on the gravitational-wave detectorsrough localization, with the goal of detecting the source by its electromagnetic signature.Given that LIGO had only just come online for testing when GW150914 was detected, its impressive that the pipeline was ready and there were observatories able to follow up so quickly! When the alert went out, 25 teams responded, mobilizing satellites and ground-based telescopes spanning 19 orders of magnitude in electromagnetic wavelength.The Search PartyThe only information the teams were initially given was the localization of the signal to roughly 600 square degrees on the sky. With this starting point, over the next three months, these 25 facilities carefully observed the entirety of the estimated localization area.Footprints of observations in comparison with the initial LIGO localization of GW150914 (black contours). Shown are radio fields (red), optical/infrared fields (green), and X-ray fields (blue circles); not shown are the all-sky Fermi GBM, LAT, INTEGRAL SPI-ACS, and MAXI observations. [Abbott et al. 2016]Some high-energy observatories, like Fermi and INTEGRAL, covered the whole sky. Many optical facilities used a tiling strategy, together covering about 900 square degrees. Still other observatories used a targeted approach, specifically looking at fields that contained a high density of nearby galaxies, in the hopes of detecting signs of a neutron-star merger or a core-collapse supernova.For the transient sources that were found, follow-up spectroscopy and further photometry was performed, to determine if the transient could have been the source of the detected gravitational waves.What Was the Outcome?No electromagnetic counterpart to GW150914 was found. It turns out this isnt surprising; GW150914 was later determined to have

  6. A framework to analyze searches for gauge bosons of the hidden light sector in electron scattering fixed target experiments

    Energy Technology Data Exchange (ETDEWEB)

    Beranek, T. [Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, D-55099 Mainz and PRISMA Cluster of Excellence, Johannes Gutenberg-Universität Mainz, D-55099 Mainz (Germany)

    2013-11-07

    Electron scattering fixed target experiments are a versatile tool to probe various kinds of physics phenomena. Recently fixed target experiments in which an electron beam is scattered off a heavy nucleus and a lepton-antilepton pair is created, i.e. e(A,Z) →e(A,Z)l{sup +}l{sup −}, were utilized to search for physics beyond the standard model at modest energies. In these experiments one searches for a small, narrow resonance in the invariant mass spectrum of the lepton-antilepton pair, arising from the exchange of a new light gauge boson γ′ coupling to the dark sector as well as very weakly to standard model particles. Such a signal would appear as an enhancement over a smooth QED background. Hence a precise understanding of the background is crucial. We present a theoretical analysis of the process e(A,Z) →e(A,Z)l{sup +}l{sup −}. Therefore we have performed an analysis of the cross section, which is then used to extract exclusion limits on the parameter space of the γ′, describing the existing experimental data taken at MAMI.

  7. Variability of Optical Counterparts in the Chandra Galactic Bulge Survey

    CERN Document Server

    Britt, Christopher T; Johnson, C B; Baldwin, A; Jonker, P G; Nelemans, G; Torres, M A P; Maccarone, T; Steeghs, D; Greiss, S; Heinke, C; Bassa, C G; Collazzi, A; Villar, A; Gabb, M; Gossen, L

    2014-01-01

    We present optical lightcurves of variable stars consistent with the positions of X-ray sources identified with the Chandra X-ray Observatory for the Chandra Galactic Bulge Survey. Using data from the Mosaic-II instrument on the Blanco 4m Telescope at CTIO, we gathered time-resolved photometric data on timescales from $\\sim2$ hr to 8 days over the $\\frac{3}{4}$ of the X-ray survey containing sources from the initial GBS catalog. Among the lightcurve morphologies we identify are flickering in interacting binaries, eclipsing sources, dwarf nova outbursts, ellipsoidal variations, long period variables, spotted stars, and flare stars. $87\\%$ of X-ray sources have at least one potential optical counterpart. $24\\%$ of these candidate counterparts are detectably variable; a much greater fraction than expected for randomly selected field stars, which suggests that most of these variables are real counterparts. We discuss individual sources of interest, provide variability information on candidate counterparts, and di...

  8. Spectroscopy of candidate electromagnetic counterparts to gravitational wave sources

    CERN Document Server

    Steele, Iain A; Piascik, Andrzej S

    2016-01-01

    A programme of worldwide, multi-wavelength electromagnetic follow-up of sources detected by gravitational wave detectors is in place. Following the discovery of GW150914 and GW151226, wide field imaging of their sky localisations identified a number of candidate optical counterparts which were then spectrally classified. The majority of candidates were found to be supernovae at redshift ranges similar to the GW events and were thereby ruled out as a genuine counterpart. Other candidates ruled out include AGN and solar system objects. Given the GW sources were black hole binary mergers, the lack of an identified electromagnetic counterpart is not surprising. However the observations show that is it is possible to organise and execute a campaign that can eliminate the majority of potential counterparts. Finally we note the existence of a "classification gap" with a significant fraction of candidates going unclassified.

  9. Search for Lepton Flavor Violating Decays τ-→l-Ks0 with the BABAR Experiment

    Science.gov (United States)

    Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E.; Prudent, X.; Tisserand, V.; Tico, J. Garra; Grauges, E.; Lopez, L.; Palano, A.; Pappagallo, M.; Eigen, G.; Stugu, B.; Sun, L.; Abrams, G. S.; Battaglia, M.; Brown, D. N.; Cahn, R. N.; Jacobsen, R. G.; Kerth, L. T.; Kolomensky, Yu. G.; Lynch, G.; Osipenkov, I. L.; Ronan, M. T.; Tackmann, K.; Tanabe, T.; Hawkes, C. M.; Soni, N.; Watson, A. T.; Koch, H.; Schroeder, T.; Walker, D.; Asgeirsson, D. J.; Fulsom, B. G.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; Barrett, M.; Khan, A.; Blinov, V. E.; Bukin, A. D.; Buzykaev, A. R.; Druzhinin, V. P.; Golubev, V. B.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Todyshev, K. Yu.; Bondioli, M.; Curry, S.; Eschrich, I.; Kirkby, D.; Lankford, A. J.; Lund, P.; Mandelkern, M.; Martin, E. C.; Stoker, D. P.; Abachi, S.; Buchanan, C.; Gary, J. W.; Liu, F.; Long, O.; Vitug, G. M.; Yasin, Z.; Zhang, L.; Sharma, V.; Campagnari, C.; Hong, T. M.; Kovalskyi, D.; Mazur, M. A.; Richman, J. D.; Beck, T. W.; Eisner, A. M.; Flacco, C. J.; Heusch, C. A.; Kroseberg, J.; Lockman, W. S.; Martinez, A. J.; Schalk, T.; Schumm, B. A.; Seiden, A.; Wilson, M. G.; Winstrom, L. O.; Cheng, C. H.; Doll, D. A.; Echenard, B.; Fang, F.; Hitlin, D. G.; Narsky, I.; Piatenko, T.; Porter, F. C.; Andreassen, R.; Mancinelli, G.; Meadows, B. T.; Mishra, K.; Sokoloff, M. D.; Bloom, P. C.; Ford, W. T.; Gaz, A.; Hirschauer, J. F.; Nagel, M.; Nauenberg, U.; Smith, J. G.; Ulmer, K. A.; Wagner, S. R.; Ayad, R.; Soffer, A.; Toki, W. H.; Wilson, R. J.; Feltresi, E.; Hauke, A.; Jasper, H.; Karbach, M.; Merkel, J.; Petzold, A.; Spaan, B.; Wacker, K.; Kobel, M. J.; Nogowski, R.; Schubert, K. R.; Schwierz, R.; Volk, A.; Bernard, D.; Bonneaud, G. R.; Latour, E.; Verderi, M.; Clark, P. J.; Playfer, S.; Watson, J. E.; Andreotti, M.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cecchi, A.; Cibinetto, G.; Franchini, P.; Luppi, E.; Negrini, M.; Petrella, A.; Piemontese, L.; Santoro, V.; Baldini-Ferroli, R.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Pacetti, S.; Patteri, P.; Peruzzi, I. M.; Piccolo, M.; Rama, M.; Zallo, A.; Buzzo, A.; Contri, R.; Vetere, M. Lo; Macri, M. M.; Monge, M. R.; Passaggio, S.; Patrignani, C.; Robutti, E.; Santroni, A.; Tosi, S.; Chaisanguanthum, K. S.; Morii, M.; Adametz, A.; Marks, J.; Schenk, S.; Uwer, U.; Klose, V.; Lacker, H. M.; Bard, D. J.; Dauncey, P. D.; Nash, J. A.; Tibbetts, M.; Behera, P. K.; Chai, X.; Charles, M. J.; Mallik, U.; Cochran, J.; Crawley, H. B.; Dong, L.; Meyer, W. T.; Prell, S.; Rosenberg, E. I.; Rubin, A. E.; Gao, Y. Y.; Gritsan, A. V.; Guo, Z. J.; Lae, C. K.; Arnaud, N.; Béquilleux, J.; D'Orazio, A.; Davier, M.; da Costa, J. Firmino; Grosdidier, G.; Höcker, A.; Diberder, F. Le; Lepeltier, V.; Lutz, A. M.; Pruvot, S.; Roudeau, P.; Schune, M. H.; Serrano, J.; Sordini, V.; Stocchi, A.; Wormser, G.; Lange, D. J.; Wright, D. M.; Bingham, I.; Burke, J. P.; Chavez, C. A.; Fry, J. R.; Gabathuler, E.; Gamet, R.; Hutchcroft, D. E.; Payne, D. J.; Touramanis, C.; Bevan, A. J.; Clarke, C. K.; George, K. A.; Lodovico, F. Di; Sacco, R.; Sigamani, M.; Cowan, G.; Flaecher, H. U.; Hopkins, D. A.; Paramesvaran, S.; Salvatore, F.; Wren, A. C.; Brown, D. N.; Davis, C. L.; Denig, A. G.; Fritsch, M.; Gradl, W.; Schott, G.; Alwyn, K. E.; Bailey, D.; Barlow, R. J.; Chia, Y. M.; Edgar, C. L.; Jackson, G.; Lafferty, G. D.; West, T. J.; Yi, J. I.; Anderson, J.; Chen, C.; Jawahery, A.; Roberts, D. A.; Simi, G.; Tuggle, J. M.; Dallapiccola, C.; Li, X.; Salvati, E.; Saremi, S.; Cowan, R.; Dujmic, D.; Fisher, P. H.; Henderson, S. W.; Sciolla, G.; Spitznagel, M.; Taylor, F.; Yamamoto, R. K.; Zhao, M.; Patel, P. M.; Robertson, S. H.; Lazzaro, A.; Lombardo, V.; Palombo, F.; Bauer, J. M.; Cremaldi, L.; Godang, R.; Kroeger, R.; Sanders, D. A.; Summers, D. J.; Zhao, H. W.; Simard, M.; Taras, P.; Viaud, F. B.; Nicholson, H.; de Nardo, G.; Lista, L.; Monorchio, D.; Onorato, G.; Sciacca, C.; Raven, G.; Snoek, H. L.; Jessop, C. P.; Knoepfel, K. J.; Losecco, J. M.; Wang, W. F.; Benelli, G.; Corwin, L. A.; Honscheid, K.; Kagan, H.; Kass, R.; Morris, J. P.; Rahimi, A. M.; Regensburger, J. J.; Sekula, S. J.; Wong, Q. K.; Blount, N. L.; Brau, J.; Frey, R.; Igonkina, O.; Kolb, J. A.; Lu, M.; Rahmat, R.; Sinev, N. B.; Strom, D.; Strube, J.; Torrence, E.; Castelli, G.; Gagliardi, N.; Margoni, M.; Morandin, M.; Posocco, M.; Rotondo, M.; Simonetto, F.; Stroili, R.; Voci, C.; Sanchez, P. Del Amo; Ben-Haim, E.; Briand, H.; Calderini, G.; Chauveau, J.; David, P.; Del Buono, L.; Hamon, O.; Leruste, Ph.; Ocariz, J.; Perez, A.; Prendki, J.; Sitt, S.; Gladney, L.; Biasini, M.; Covarelli, R.; Manoni, E.; Angelini, C.; Batignani, G.; Bettarini, S.; Carpinelli, M.; Cervelli, A.; Forti, F.; Giorgi, M. A.; Lusiani, A.

    2009-01-01

    A search for the lepton flavor violating decays τ-→l-KS0 (l=e or μ) has been performed using a data sample corresponding to an integrated luminosity of 469fb-1, collected with the BABAR detector at the SLAC PEP-II e+e- asymmetric energy collider. No statistically significant signal has been observed in either channel and the estimated upper limits on branching fractions are B(τ-→e-KS0)<3.3×10-8 and B(τ-→μ-KS0)<4.0×10-8 at 90% confidence level.

  10. Search for mirror dark matter in a laboratory experiment with ultracold neutrons

    CERN Document Server

    Serebrov, A P; Dovator, N A; Dmitriev, S P; Fomin, A K; Geltenbort, P; Kharitonov, A G; Krasnoschekova, I A; Lasakov, M S; Murashkin, A N; Shmelev, G E; Varlamov, V E; Vassiljev, A V; Zherebtsov, O M; Zimmer, O

    2008-01-01

    Mirror matter is considered as a candidate for dark matter. To investigate this possibility an experimental search for neutron - mirror neutron transitions has been carried out using storage of ultracold neutrons in a trap with different magnetic fields. As a result, a new limit for the neutron - mirror neutron oscillation time tau_osc has been obtained, tau_osc >= 448 s (90% C.L.). As a side result, some restriction of the presence of a mirror magnetic field in the range 0 - 1200 nT has been obtained.

  11. Repeating Pulsed Magnet System for Axion-like Particle Searches and Vacuum Birefringence Experiments

    CERN Document Server

    Yamazaki, T; Namba, T; Asai, S; Kobayashi, T; Matsuo, A; Kindo, K; Nojiri, H

    2016-01-01

    We have developed a repeating pulsed magnet system which generates magnetic fields of about 10 T in a direction transverse to an incident beam over a length of 0.8 m with a repetition rate of 0.2 Hz. Its repetition rate is by two orders of magnitude higher than usual pulsed magnets. It is composed of four low resistance racetrack coils and a 30 kJ transportable capacitor bank as a power supply. The system aims at axion-like particle searches with a pulsed light source and vacuum birefringence measurements. We report on the details of the system and its performances.

  12. Short review on solar neutrinos experiments and search for sterile neutrinos with solar neutrino detectors

    Directory of Open Access Journals (Sweden)

    Pallavicini Marco

    2015-01-01

    Full Text Available The spectroscopy of solar neutrinos is now entering the precision era, after a golden age which has led to the discovery of neutrino oscillations and the MSW effect. In this paper we summarise the current experimental knowledge in the field and its future perspectives, showing that solar neutrino detectors are and will remain a crucial tool for a deeper understanding of stars, neutrinos, and fundamental physics. We also show that solar neutrinos may become pivotal for the search of sterile neutrinos.

  13. Search for Decays of the Λ$0\\atop{b}$ Baryon with the D0 Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Camacho, Enrique [The Center for Research and Advanced Studies of the National Polytechnic Inst., Mexico D.F. (Mexico)

    2011-11-25

    This thesis presents work I performed within the D0 Collaboration to make the measurement of the Branching Ratio of Λ$0\\atop{b}$ baryon in the channel Λ$0\\atop{b}$ → J/ΨΛ0 . The b-hadron such as the Λ$0\\atop{b}$ are currently the subject of much research in both the theorical and experimental particle physics communities. Measurements of the production and decays of b-hadrons can improve the understanding of the electroweak and strong interactions described by the Standard Model of particle physics, as well as proving opportunities to search for physics beyond the Standard Model.

  14. Repeating pulsed magnet system for axion-like particle searches and vacuum birefringence experiments

    Science.gov (United States)

    Yamazaki, T.; Inada, T.; Namba, T.; Asai, S.; Kobayashi, T.; Matsuo, A.; Kindo, K.; Nojiri, H.

    2016-10-01

    We have developed a repeating pulsed magnet system which generates magnetic fields of about 10 T in a direction transverse to an incident beam over a length of 0.8 m with a repetition rate of 0.2 Hz. Its repetition rate is by two orders of magnitude higher than usual pulsed magnets. It is composed of four low resistance racetrack coils and a 30 kJ transportable capacitor bank as a power supply. The system aims at axion-like particle searches with a pulsed light source and vacuum birefringence measurements. We report on the details of the system and its performances.

  15. Search for the pentaquark candidate $\\Theta^+$(1540) in the hyperon beam experiment WA89

    CERN Document Server

    Adamovich, M I; Baranov, S P; Barberis, D; Beck, M; Bérat, C; Beusch, W; Boss, M; Brons, S; Brückner, W; Buénerd, M; Busch, C; Büscher, C; Charignon, F; Chauvin, J; Chudakov, E A; Dersch, U; Dropmann, F; Engelfried, J; Faller, F; Fournier, A; Gerassimov, S G; Godbersen, M; Grafström, P; Haller, T; Heidrich, M; Hubbard, E; Hurst, R B; Königsmann, K C; Konorov, I; Keller, N; Martens, K; Martin, P; Masciocchi, S; Michaels, R; Müller, U; Neeb, H; Newbold, D; Newsom, C; Paul, S; Pochodzalla, J; Potashnikova, I; Povh, B; Ransome, R; Ren, Z; Epherre-Rey-Campagnolle, Marcelle; Rosner, G; Rossi, L; Rudolph, H; Scheel, C; Schmitt, L; Siebert,H W; Simon, A; Smith, V J; Thilmann, O; Trombini, A; Vesin, E; Volkemer, B; Vorwalter, K; Walcher, T; Wälder, G; Werding, R; Wittmann, E; Zavertyaev, M V

    2005-01-01

    We report on a high-statistics search for the \\t1540 resonance in $\\Sigma^-$-nucleus collisions at 340 \\gevc1 . No evidence for this resonance was found in our data sample which contains 13 millions $K^0_s \\to \\pi^+\\pi^- $ decays above background. For the decay channel $\\Theta^+ \\to K^0_s p$ and the kinematic range $x_F>$ 0.05 we find the production cross section to be $BR(\\Theta^+ \\to K^0_s p)\\cdot \\sigma_0 <$ 1.8 $\\mu$b per nucleon at 99% CL.

  16. New physics searches with b-hadrons at the ATLAS experiment

    CERN Document Server

    Smirnova, l; The ATLAS collaboration

    2014-01-01

    Flavour changing neutral currents and precision measurements of CP violation are investigated in ATLAS as probes to new physics beyond the standard model. This talk presents the most recent results on the search for the rare decay B0s → μ+μ-, as well as providing the latest update on the study of the different angular amplitudes contributing to flavour tagged B0s → J/ψ (μ+μ-)φ (K+K-) decays. The latter analysis measures the CP-violating phase φs, as well as the average Bs meson lifetime Γs and the decay width difference ΔΓs.

  17. New physics searches with b-hadrons in the ATLAS experiment

    CERN Document Server

    Smirnova, L; The ATLAS collaboration

    2014-01-01

    Flavour changing neutral currents and precision measurements of CP violation are investigated in ATLAS as probes to new physics beyond the standard model. This talk presents the most recent results on the search for the rare decay Bs (B0) -> mu+mu-, as well as providing the latest update on the study of the different angular amplitudes contributing to flavour tagged Bs -> J/psi phi (mu+mu-K+K-) decays. The latter analysis measures the CP-violating phase phi_s, as well as the average B_s meson lifetime Gamma_s and the decay width difference DeltaGamma_s.

  18. Search for a Vector Boson Fusion Higgs boson production in the di-photon channel with the ATLAS experiment

    CERN Document Server

    Petit, E; The ATLAS collaboration

    2012-01-01

    This poster was made for the HCP conference. The initial title submitted to the conference organisation committee was "Search for an associated Higgs boson production in the di-photon channel with the ATLAS experiment" and was about the details of the VH measurements in the di-photon channel with 13 fb-1 of data, and the implications in terms of Higgs boson couplings. But since the H->gammagamma was finally not approved to go for HCP, the title and the content of the posters changed from the VH production mode to the VBF production mode (for which we have results with the ICHEP dataset).

  19. Electroweak Physics in the forward region and b$\\overline b$ resonances search at the LHCb experiment

    CERN Document Server

    Sestini, L

    2016-01-01

    The LHCb experiment offers a complementary phase space region with respect to ATLAS and CMS to study electroweak processes, thanks to the unique acceptance and the large bandwidth trigger at low energy threshold. Here, the latest measurements performed during the LHC Run-I data taking are presented, setting the scene for the future. Possible developments in this sector are discussed, in particular the search for b$\\overline b$ resonances, considered preferred channels in the observation of new exotic states and New Physics.

  20. Search for the production of four top quarks at the CMS experiment at $\\sqrt{s}$ = 13 TeV

    CERN Document Server

    Beck, Lana Margaret Gwen

    2016-01-01

    A combined search for standard model four-top-quark production in the single lepton plus jets and dilepton channels will be presented. The analysis utilises the 2015 dataset recorded by the CMS experiment at sqrt(s) = 13 TeV which corresponds to an integrated luminosity of 2.6 fb-1. A scheme based on a boosted decision tree algorithm is used to select signal and suppress backgrounds. An upper limit on the cross section of four-top-quark production will be presented.

  1. Search for new physics in events with opposite-sign dileptons and missing transverse energy with the CMS experiment

    Directory of Open Access Journals (Sweden)

    Sprenger Daniel

    2012-06-01

    Full Text Available The results of a search for new physics in events with two opposite-sign isolated electrons or muons, hadronic activity, and missing transverse energy in the final state are presented. The results are based on analysis of a data sample with a corresponding integrated luminosity of 0.98 fb−1 produced in pp collisions at a center-of-mass energy of 7 TeV collected by the CMS experiment at the LHC. No evidence for an event yield beyond Standard-Model expectations is found, and constraints on supersymmetric models are deduced from these observations.

  2. New Results from the Search for Low-Mass Weakly Interacting Massive Particles with the CDMS Low Ionization Threshold Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Agnese, R.; Anderson, A. J.; Aramaki, T.; Asai, M.; Baker, W.; Balakishiyeva, D.; Barker, D.; Basu Thakur, R.; Bauer, D. A.; Billard, J.; Borgland, A.; Bowles, M. A.; Brink, P. L.; Bunker, R.; Cabrera, B.; Caldwell, D. O.; Calkins, R.; Cerdeno, D. G.; Chagani, H.; Chen, Y.; Cooley, J.; Cornell, B.; Cushman, P.; Daal, M.; Di Stefano, P. C. F.; Doughty, T.; Esteban, L.; Fallows, S.; Figueroa-Feliciano, E.; Ghaith, M.; Godfrey, G. L.; Golwala, S. R.; Hall, J.; Harris, H. R.; Hofer, T.; Holmgren, D.; Hsu, L.; Huber, M. E.; Jardin, D.; Jastram, A.; Kamaev, O.; Kara, B.; Kelsey, M. H.; Kennedy, A.; Leder, A.; Loer, B.; Lopez Asamar, E.; Lukens, P.; Mahapatra, R.; Mandic, V.; Mast, N.; Mirabolfathi, N.; Moffatt, R. A.; Morales Mendoza, J. D.; Oser, S. M.; Page, K.; Page, W. A.; Partridge, R.; Pepin, M.; Phipps, A.; Prasad, K.; Pyle, M.; Qiu, H.; Rau, W.; Redl, P.; Reisetter, A.; Ricci, Y.; Roberts, A.; Rogers, H. E.; Saab, T.; Sadoulet, B.; Sander, J.; Schneck, K.; Schnee, R. W.; Scorza, S.; Serfass, B.; Shank, B.; Speller, D.; Toback, D.; Underwood, R.; Upadhyayula, S.; Villano, A. N.; Welliver, B.; Wilson, J. S.; Wright, D. H.; Yellin, S.; Yen, J. J.; Young, B. A.; Zhang, J.

    2016-02-01

    The CDMS low ionization threshold experiment (CDMSlite) uses cryogenic germanium detectors operated at a relatively high bias voltage to amplify the phonon signal in the search for weakly interacting massive particles (WIMPs). Results are presented from the second CDMSlite run with an exposure of 70 kg day, which reached an energy threshold for electron recoils as low as 56 eV. A fiducialization cut reduces backgrounds below those previously reported by CDMSlite. New parameter space for the WIMP-nucleon spin-independent cross section is excluded for WIMP masses between 1.6 and 5.5 GeV/c^2.

  3. SEARCH: An Interactive Computer Program for Optimizing Two-Variable, Unconstrained Experiments or Simulation.

    Science.gov (United States)

    1988-03-01

    eleven experiments were used, the new interval would be 0.008 the size of the original interval (4:42-43). In addition. Himmelblau *recommends a... Himmelblau , David M. Applied Nonlinear PrQgramminj. Nuw York: McGraw-Hill Book Co., 1972 5. Montgomery, Douglas C. Design and Analysis of Experiments

  4. Limits on Active to Sterile Neutrino Oscillations from Disappearance Searches in the MINOS, Daya Bay, and Bugey-3 Experiments.

    Science.gov (United States)

    Adamson, P; An, F P; Anghel, I; Aurisano, A; Balantekin, A B; Band, H R; Barr, G; Bishai, M; Blake, A; Blyth, S; Bock, G J; Bogert, D; Cao, D; Cao, G F; Cao, J; Cao, S V; Carroll, T J; Castromonte, C M; Cen, W R; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chen, H S; Chen, Q Y; Chen, R; Chen, S M; Chen, Y; Chen, Y X; Cheng, J; Cheng, J-H; Cheng, Y P; Cheng, Z K; Cherwinka, J J; Childress, S; Chu, M C; Chukanov, A; Coelho, J A B; Corwin, L; Cronin-Hennessy, D; Cummings, J P; de Arcos, J; De Rijck, S; Deng, Z Y; Devan, A V; Devenish, N E; Ding, X F; Ding, Y Y; Diwan, M V; Dolgareva, M; Dove, J; Dwyer, D A; Edwards, W R; Escobar, C O; Evans, J J; Falk, E; Feldman, G J; Flanagan, W; Frohne, M V; Gabrielyan, M; Gallagher, H R; Germani, S; Gill, R; Gomes, R A; Gonchar, M; Gong, G H; Gong, H; Goodman, M C; Gouffon, P; Graf, N; Gran, R; Grassi, M; Grzelak, K; Gu, W Q; Guan, M Y; Guo, L; Guo, R P; Guo, X H; Guo, Z; Habig, A; Hackenburg, R W; Hahn, S R; Han, R; Hans, S; Hartnell, J; Hatcher, R; He, M; Heeger, K M; Heng, Y K; Higuera, A; Holin, A; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, T; Hu, W; Huang, E C; Huang, H X; Huang, J; Huang, X T; Huber, P; Huo, W; Hussain, G; Hylen, J; Irwin, G M; Isvan, Z; Jaffe, D E; Jaffke, P; James, C; Jen, K L; Jensen, D; Jetter, S; Ji, X L; Ji, X P; Jiao, J B; Johnson, R A; de Jong, J K; Joshi, J; Kafka, T; Kang, L; Kasahara, S M S; Kettell, S H; Kohn, S; Koizumi, G; Kordosky, M; Kramer, M; Kreymer, A; Kwan, K K; Kwok, M W; Kwok, T; Lang, K; Langford, T J; Lau, K; Lebanowski, L; Lee, J; Lee, J H C; Lei, R T; Leitner, R; Leung, J K C; Li, C; Li, D J; Li, F; Li, G S; Li, Q J; Li, S; Li, S C; Li, W D; Li, X N; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, S; Lin, S K; Lin, Y-C; Ling, J J; Link, J M; Litchfield, P J; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, J C; Liu, J L; Loh, C W; Lu, C; Lu, H Q; Lu, J S; Lucas, P; Luk, K B; Lv, Z; Ma, Q M; Ma, X B; Ma, X Y; Ma, Y Q; Malyshkin, Y; Mann, W A; Marshak, M L; Martinez Caicedo, D A; Mayer, N; McDonald, K T; McGivern, C; McKeown, R D; Medeiros, M M; Mehdiyev, R; Meier, J R; Messier, M D; Miller, W H; Mishra, S R; Mitchell, I; Mooney, M; Moore, C D; Mualem, L; Musser, J; Nakajima, Y; Naples, D; Napolitano, J; Naumov, D; Naumova, E; Nelson, J K; Newman, H B; Ngai, H Y; Nichol, R J; Ning, Z; Nowak, J A; O'Connor, J; Ochoa-Ricoux, J P; Olshevskiy, A; Orchanian, M; Pahlka, R B; Paley, J; Pan, H-R; Park, J; Patterson, R B; Patton, S; Pawloski, G; Pec, V; Peng, J C; Perch, A; Pfützner, M M; Phan, D D; Phan-Budd, S; Pinsky, L; Plunkett, R K; Poonthottathil, N; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Qiu, X; Radovic, A; Raper, N; Rebel, B; Ren, J; Rosenfeld, C; Rosero, R; Roskovec, B; Ruan, X C; Rubin, H A; Sail, P; Sanchez, M C; Schneps, J; Schreckenberger, A; Schreiner, P; Sharma, R; Moed Sher, S; Sousa, A; Steiner, H; Sun, G X; Sun, J L; Tagg, N; Talaga, R L; Tang, W; Taychenachev, D; Thomas, J; Thomson, M A; Tian, X; Timmons, A; Todd, J; Tognini, S C; Toner, R; Torretta, D; Treskov, K; Tsang, K V; Tull, C E; Tzanakos, G; Urheim, J; Vahle, P; Viaux, N; Viren, B; Vorobel, V; Wang, C H; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, X; Wang, Y F; Wang, Z; Wang, Z M; Webb, R C; Weber, A; Wei, H Y; Wen, L J; Whisnant, K; White, C; Whitehead, L; Whitehead, L H; Wise, T; Wojcicki, S G; Wong, H L H; Wong, S C F; Worcester, E; Wu, C-H; Wu, Q; Wu, W J; Xia, D M; Xia, J K; Xing, Z Z; Xu, J L; Xu, J Y; Xu, Y; Xue, T; Yang, C G; Yang, H; Yang, L; Yang, M S; Yang, M T; Ye, M; Ye, Z; Yeh, M; Young, B L; Yu, Z Y; Zeng, S; Zhan, L; Zhang, C; Zhang, H H; Zhang, J W; Zhang, Q M; Zhang, X T; Zhang, Y M; Zhang, Y X; Zhang, Z J; Zhang, Z P; Zhang, Z Y; Zhao, J; Zhao, Q W; Zhao, Y B; Zhong, W L; Zhou, L; Zhou, N; Zhuang, H L; Zou, J H

    2016-10-07

    Searches for a light sterile neutrino have been performed independently by the MINOS and the Daya Bay experiments using the muon (anti)neutrino and electron antineutrino disappearance channels, respectively. In this Letter, results from both experiments are combined with those from the Bugey-3 reactor neutrino experiment to constrain oscillations into light sterile neutrinos. The three experiments are sensitive to complementary regions of parameter space, enabling the combined analysis to probe regions allowed by the Liquid Scintillator Neutrino Detector (LSND) and MiniBooNE experiments in a minimally extended four-neutrino flavor framework. Stringent limits on sin^{2}2θ_{μe} are set over 6 orders of magnitude in the sterile mass-squared splitting Δm_{41}^{2}. The sterile-neutrino mixing phase space allowed by the LSND and MiniBooNE experiments is excluded for Δm_{41}^{2}<0.8  eV^{2} at 95%  CL_{s}.

  5. Search for new physics in the diphoton channel at the ATLAS experiment at the LHC

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00386351; Delmastro, Marco

    The topic of this thesis is the search for resonances in the di-photon invariant mass spectrum. These resonances are predicted by several models beyond the Standard Model. The analysis of data provided by the ATLAS detector during the Run-2 (years 2015-2016) of LHC will be presented. The di-photon decay channel is used both for precision measurement, for example for the measurement of the Higgs boson mass, and for discovery of BSM physics, like search for Gravitons in the extra dimension context and Higgs bosons in the Two Higgs doublet model context. In the ATLAS detector photons are reconstructed combining the information from the tracker and the electromagnetic calorimeter: the energy of the photons is measured in the calorimeter while the inner detector is used to reconstruct conversions. Their signature is quite simple and they are reconstructed and measured with a good energy resolution, purity and selection efficiency. The main background in photon-related analyses is coming from jets mis-identified...

  6. Search for Neutral MSSM Higgs bosons decaying to tau pairs in the ATLAS experiment

    CERN Multimedia

    Scutti, F

    2013-01-01

    The Minimal Supersymmetric Standard Model (MSSM) is a supersymmetric extension of the Standard Model of particle physics, predicting the existence of five Higgs bosons, two charged (H±) and three neutral (h, H, A). At tree level their properties are determined by two independent parameters: the mass of the CP-odd Higgs boson mA, and the ratio between the vacuum expectation values of the two Higgs doublets predicted tan(beta). In Supersymmetric models, the Higgs boson couplings to down-type fermions like b-quarks or tau leptons is significantly enhanced over a large region of the parameter space. Decays to tau lepton pairs occur 10% of the times and provide a cleaner environment for the search than decays to b-quarks. The tau lepton can decay into either a muon or an electron, plus neutrinos, or in hadrons plus neutrinos. In this poster, the search for the heavy neutral MSSM Higgses (h, H, A) is presented, where the final state is a pair of hadronically decaying tau leptons. This channel provides good sensit...

  7. Search for Gluinos using Final States with One Isolated Lepton in the LHC- ATLAS Experiment

    CERN Document Server

    Chen, Shion

    This thesis presents the updated search for gluinos via proton-proton collisions with the center- of-mass energy of √s = 13 TeV at LHC, by focusing on the final state with exactly one lepton. With respect to the past searches, the sensitivity to heavier gluino is gained using the improved analysis technique and updated data statistics (36.1 fb−1 of integrated luminosity) collected in the ATLAS detector. No significant data excess is found in the unblinded dataset, and the exclusion limits are set on various targeted gluino decay scenarios. As a general conclusion, it is confirmed that up to 1.7 TeV ∼ 2.0 TeV in gluino mass and up to ∼ 1 TeV in the lightest neutralino mass is excluded for typical mass spectra, while the limit extends up to 1.5 TeV ∼ 1.9 TeV in gluino mass for the mass spectra motivated by the well-tempered neutralino scenario.

  8. Selective searching while driving: the role of experience in hazard detection and general surveillance.

    Science.gov (United States)

    Underwood, Geoffrey; Crundall, David; Chapman, Peter

    2002-01-15

    Novice drivers have been found in previous studies to display a limited search of the immediate environment, relative to experienced drivers, when manoeuvring on a dual-carriageway road. The present study investigated whether this reduction in the variance of search along the horizontal plane was a product of less frequent glancing in the car's mirrors. Novice and experienced drivers were observed as they made lane changes in relatively unobstructed conditions and when they needed to move into a lane already occupied by traffic. Novice drivers were found to rely more than experienced drivers upon their internal mirror, even when the lane-changing manoeuvre required information about traffic in the lane best reflected in the external, door-mounted mirror. Novices did increase their use of the external mirror in response to driving needs, suggesting that they did have an awareness of the situation that required inter-weaving with traffic in their destination lane. Their reliance upon the internal mirror may be a product of a habit acquired specifically for the driver licensing examination, in which exaggerated inspection of the internal mirror is regarded as being desirable.

  9. Experience of Using a Multi-Cathode Counter (MCC) in a Search for Hidden Photon CDM

    CERN Document Server

    Kopylov, A V; Petukhov, V V

    2015-01-01

    We report on a new technique of a Multi-Cathode Counter (MCC) developed to search for hidden photon (HP) cold dark matter (CDM) with a mass from 5 to 500 eV. The method suggested in the assumption that hidden photons of the mass greater than a work function of the metal, the cathode of the counter is fabricated induce emission of single electrons from a cathode. Three configurations of the same counter are used to measure the count rates R1, R2 and R3 of the single electron events during several weeks. As a measure of the effect from HP the difference R1-(R2-D3/D2xR3) has been used. Some preliminary results have been obtained on a first try to search for HP with a mass from 5 to 500 eV. The upper limit for mixing parameter X has been set on the level of 3.3x10-10 for hidden photon mass from 9 to 100 eV. In our plans is to refine the procedure of data treatment and to continue the measurements to collect more data.

  10. Search for $W' \\rightarrow tb \\rightarrow qqbb$ with Novel Techniques at the ATLAS Experiment

    CERN Document Server

    Li, Ho Ling

    This thesis presents the first search for a massive $W'$ gauge boson in the decay channel of $tb \\rightarrow Wbb \\rightarrow qqbb$, performed with data corresponding to $20.3~{\\rm fb}^{-1}$ of integrated luminosity collected by the ATLAS detector at the LHC in $pp$ collisions at a center-of-mass energy of $\\sqrt{s} = 8~TeV$. This analysis searches for $W'$ with masses above $1.5~TeV$, where the $W'$ decay products have large momentum. Novel jet substructure techniques are used to identify jets from high momentum top quarks to ensure high sensitivity, independent of $W'$ mass, up to $3~TeV$; $b$-tagging is also used to identify jets originating from bottom quarks. The data is consistent with the Standard Model background-only expectations, and 95% Confidence Level limits are set on the $W' \\rightarrow tb$ cross section times branching ratio ranging from $0.16\\;\\mathrm{pb}$ to $0.33\\;\\mathrm{pb}$ for left-handed $W'$ bosons, and ranging from $0.10\\;\\mathrm{pb}$ to $0.21\\;\\mathrm{pb}$ for right-handed $W'$. In a...

  11. The Search Performance Evaluation and Prediction in Exploratory Search

    OpenAIRE

    2016-01-01

    The exploratory search for complex search tasks requires an effective search behavior model to evaluate and predict user search performance. Few studies have investigated the relationship between user search behavior and search performance in exploratory search. This research adopts a mixed approach combining search system development, user search experiment, search query log analysis, and multivariate regression analysis to resolve the knowledge gap. Through this study, it is shown that expl...

  12. The Search Performance Evaluation and Prediction in Exploratory Search

    OpenAIRE

    Liu, Fei

    2016-01-01

    The exploratory search for complex search tasks requires an effective search behavior model to evaluate and predict user search performance. Few studies have investigated the relationship between user search behavior and search performance in exploratory search. This research adopts a mixed approach combining search system development, user search experiment, search query log analysis, and multivariate regression analysis to resolve the knowledge gap. Through this study, it is shown that expl...

  13. Is robotic mitral valve surgery more expensive than its conventional counterpart?

    Science.gov (United States)

    Canale, Leonardo Secchin; Colafranceschi, Alexandre Siciliano

    2015-06-01

    A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'Is robotic mitral valve surgery more expensive than its conventional counterpart?' Altogether 19 papers were found using the reported search, of which 5 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. There is a general impression in the surgical community that robotic operations might incur prohibitive additional costs. There is a paucity of data in the literature regarding cost analysis in cardiac robotic surgery. From the five studies, four were single institution experiences and one was a database inquiry study. These four studies showed that operational costs are higher for robotic cases but this was partially (one study) or completely (three studies) offset by lower postoperative costs. Overall hospital costs were similar between the two approaches in three studies and one study showed higher costs in the robotic group. Higher operating theatre (OT) costs were driven mainly by use of robotic instruments (approximately US$1500 per case) and longer OT times. Savings in postoperative care were driven by shorter length of hospital stay (on average 2 days fewer in robotic cases) and lower morbidity. If amortization cost, that is, the value of the initial capital investment on the robotic system divided by all operations performed, is included in this analysis, robotic approach becomes significantly more expensive by approximately US$3400 per case. The fifth study was a large national database inquiry in which robotic approach was found to be more expensive by US$600 per case excluding amortization cost and by US$3700 if amortization is included. We conclude that the total hospital cost of robotic mitral valve surgery is slightly higher than conventional sternotomy surgery. If

  14. Search for the Production of Gluinos and Squarks with the CDF II Experiment at the Tevatron Collider

    Energy Technology Data Exchange (ETDEWEB)

    De Lorenzo, Gianluca [Autonomous Univ. of Barcelona (Spain)

    2010-05-19

    sbottom decays exclusively as $\\tilde{b}$1 → b$\\tilde{x}$10. The expected signal for direct sbottom pair production is characterized by the presence of two jets of hadrons from the hadronization of the bottom quarks and E=T from the two LSPs in the final state. The events are selected with large ET and two energetic jets in the final state, and at least one jet is required to be associated with a b quark. The measurements are in good agreement with SM predictions for backgrounds. The results are translated into 95% CL exclusion limits on production cross sections and sbottom and neutralino masses in the given MSSM scenario. Cross sections down to 0.1 pb are excluded for the sbottom mass range considered. Sbottom masses up to 230 GeV/c2 are excluded at 95% CL for neutralino masses below 70 GeV/c2. This analysis increases the previous CDF limit by more than 40 GeV/c2. The sensitivity of both the inclusive and the exclusive search is dominated by systematic effects and the results of the two analyses can be considered as conclusive for CDF Run II. With the new energy frontier of the newly commissioned Large Hadron Collider in Geneva, the experience from Tevatron will be of crucial importance in the developing of effective strategies to search for SUSY in the next era of particle physics experiments.

  15. A search for neutral B meson oscillations at the Tevatron collider experiment DO

    Science.gov (United States)

    Krop, Dan

    We present a search for B0s oscillations using semileptonic Bs → DsmuX (Ds → K0SK ). The data were collected using the DO detector from events produced in s = 1.96 TeV proton-antiproton collisions at the Fermilab Tevatron. The Tevatron is currently the only place in the world that produces B0s mesons and will be until early 2008 when the Large Hadron Collider begins operating at CERN. One of the vital ingredients for the search for B0s oscillations is the determination of the flavor of the B0s candidate ( B0s or B¯0s ) at the time of its production, called initial state flavor tagging. We develop an likelihood based initial state flavor tagger that uses objects on the side of the event opposite to the reconstructed B meson candidate. To improve the performance of this flavor tagger, we have made it multidimensional so that it takes correlations between discriminants into account. This tagging is then certified by applying it to sample of semimuonic B(0,+) decays and measuring the well-known oscillation frequency Deltamd. We obtain Delta md = 0.486 +/- 0.021 ps-1, consistent with the world average. The tagging performance is characterized by the effective efficiency, eD2 = (1.90 +/- 0.41)%. We then turn to the search for B0s oscillations in the above-named channel. A special two-dimensional mass fitting procedure is developed to separate kinematic reflections from signal events. Using this mass fitting procedure in an unbinned likelihood framework, we obtain a 95% C.L. of Deltams > 1.10 ps-1 and a sensitivity of 1.92 ps-1. This result is combined with other analyzed B0s decay channels at DO to obtain a combined 95% C.L. of Delta ms > 14.9 ps.1 and a sensitivity of 16.5 ps-1. The corresponding log likelihood scan has a preferred value of Delta ms = 19 ps-1 with a 90% confidence level interval of 17 < Deltams < 21 ps -1, assuming Gaussian uncertainties. A comparison of the change in the likelihood between Deltams = 19 ps -1 and Deltams = infinity yields an 8

  16. Preliminary Design of a Pendulum Experiment for Searching for a Lorentz-Violation Signal

    CERN Document Server

    Shao, Cheng-Gang; Tan, Yu-Jie

    2016-01-01

    This work mainly presents a preliminary design for a pendulum experiment with both the source mass and the test mass in a striped pattern to amplify the Lorentz-violation signal, since the signal is sensitive to edge effects.

  17. Search for high-mass resonances decaying into muon pairs with the CMS experiment at LHC

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00366535; Nuzzo, Salvatore

    A search for new narrow resonances in dimuon invariant mass spectra has been performed using data obtained from proton-proton collisions at a centre-of-mass energy of $\\sqrt{s}=13$ TeV. The integrated luminosity corresponds to $2.8~\\mathrm{fb}^{-1}$. No evidence for non-standard-model physics is found, nor when these results are combined with the dielectron channel. Upper bounds are set on the masses of hypothetical particles that arise in new-physics scenarios. For the $Z'_{SSM}$ particle, which arises in the sequential standard model, and for the superstring inspired $Z'_{\\psi}$ particle, 95% confidence level lower mass limits for the combined channels are found to be $3.15$ and $2.60$ TeV, respectively. These results extend previous limits significantly.

  18. Search for 1st Generation Leptoquarks in the eejj channel with the DZero experiment

    Energy Technology Data Exchange (ETDEWEB)

    Barfuss, Anne-Fleur [Univ. of the Mediterranean, Marseille (France)

    2008-09-12

    An evidence of the existence of leptoquarks (LQ) would prove the validity of various extensions of the Standard Model of Particle Physics (SM). The search for first generation leptoquarks presented in this dissertation has been performed by analyzing a 1.02 fb-1 sample of data collected by the D0 detector, events with a final state comprising two light jets and two electrons. The absence of an excess of events in comparison to SM expectations leads to exclude scalar LQ masses up to 292 GeV and vector LQ masses from 350 to 458 GeV, depending on the LQ-l-q coupling type. The great importance of a good jet energy measurement motivated the study of the instrumental backgrounds correlated to the calorimeter, as much as studies of the hadronic showers energy resolution in γ + jets events.

  19. Search for nucleon decays induced by GUT magnetic monopoles with the MACRO experiment

    CERN Document Server

    Ambrosio, M; Auriemma, G; Bakari, D; Baldini, A; Barbarino, G C; Barish, B C; Battistoni, G; Becherini, Y; Bellotti, R; Bemporad, C; Bernardini, P; Bilokon, H; Bloise, C; Bower, C; Brigida, M; Bussino, S; Cafagna, F; Calicchio, M; Campana, D; Carboni, M; Caruso, R; Cecchini, S; Cei, F; Chiarella, V; Choudhary, B C; Coutu, S; Cozzi, M; De Cataldo, G; Dekhissi, H; De Marzo, C; De Mitri, I; Derkaoui, J E; De Vincenzi, M; Di Credico, A; Erriquez, O; Favuzzi, C; Forti, C; Fusco, P; Giacomelli, G; Giannini, G; Giglietto, N; Giorgini, M; Grassi, M; Grillo, A; Guarino, F; Gustavino, C; Habig, A; Hanson, K; Heinz, R; Iarocci, E; Katsavounidis, E; Katsavounidis, I; Kearns, E; Kim, H; Kyriazopoulou, S; Lamanna, E; Lane, C; Levin, D S; Lipari, P; Longley, N P; Longo, M J; Loparco, F; Maaroufi, F; Mancarella, G; Mandrioli, G; Manzoor, S; Margiotta, A; Marini, A; Martello, D; Marzari-Chiesa, A; Mazziotta, M N; Michael, D G; Monacelli, P; Montaruli, T; Monteno, M; Mufson, S L; Musser, J; Nicolò, D; Nolty, R; Orth, C; Osteria, G; Palamara, O; Patera, V; Patrizii, L; Pazzi, R; Peck, C W; Perrone, L; Petrera, S; Pistilli, P; Popa, V; Rainó, A; Reynoldson, J; Ronga, F; Rrhioua, A; Satriano, C; Scapparone, E; Scholberg, K; Sciubba, A; Serra, P; Sioli, M; Sirri, G; Sitta, M; Spinelli, P; Spinetti, M; Spurio, M; Steinberg, R; Stone, J L; Sulak, L R; Surdo, A; Tarle, G; Togo, V; Vakili, M; Walter, C W; Webb, R

    2002-01-01

    The interaction of a grand unification magnetic monopole with a nucleon can lead to a baryon-number violating process in which the nucleon decays into a lepton and one or more mesons (catalysis of nucleon decay). In this paper we report an experimental study of the effects of a catalysis process in the MACRO detector. Using a dedicated analysis we obtain new magnetic monopole (MM) flux upper limits at the level of ~3.10/sup -16/ cm/sup -2/ s/sup -1/ sr/sup -1/ for 1.1.10/sup -4/ search for catalysis events in the MACRO data. We also analyze the dependence of the MM flux limit on the catalysis cross section. (27 refs).

  20. First results from the H sub 0 di-baryon search and hyperon production measurements by the AGS Experiment 896.

    CERN Document Server

    Caines, H; Bellwied, R; Bennett, M; Boemi, D; Bonner, B; Caccia, Z; Christie, W; Cina, G; Costa, S; Crawford, H; Cronqvist, M; Debbe, R; Engelage, J; Flores, I; Greiner, L; Hallman, T; Hoffman, G; Huang, H; Humanic, T J; Igo, G; Insolia, A; Jensen, P; Judd, E; Kainz, K; Kaplan, M; Kelly, S; Kotov, I; Kunde, G; Lindstrom, P; Ljubicic, T; Llope, W J; Lo Curto, G; Longacre, R; Lynn, D; Madansky, L; Mahzeh, N; Milosevich, Z; Mitchell, J T; Mitchell, J; Nehmeh, S; Nociforo, C; Paganis, S; Pandey, S U; Potenza, R; Platner, E; Riley, P; Russ, D; Saulys, A; Schambach, J; Sheen, J; Stokley, C; Sugarbaker, E R; Takahashi, J; Tang, J; Trentalange, S; Tricomi, A; Tull, C; Tuvé, C; Whitfield, J; Wilson, K

    1999-01-01

    The AGS Experiment 896 was designed to study strangeness production in Au--Au collisions at 11.6A GeV/c, in particular the formation of a six-quark di-baryon the H sub 0. Heavy ion collisions provide favorable conditions for the H sub 0 formation either via coalescence of two LAMBDA particles (owing to the large LAMBDA production cross section) or direct production from the possible formation of a quark-gluon plasma. E896 also measured strange meson and baryon distributions from mid-rapidity. Preliminary results from this experiment are presented as well as details of the expected sensitivity for the H sub 0 search.

  1. Searching for t anti t resonances in the ATLAS experiment at {radical}(s) = 7 TeV

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Fajardo, Luz Stella [Desy, Zeuthen (Germany)

    2012-07-01

    New resonances decaying into top quark pairs (t anti t) are predicted by many models beyond the standard model and its pursuit is one of the targets of the ATLAS experiment at the CERN Large Hadron Collider (LHC). For this goal, two final topologies are considered: e+jets and {mu}+jets, resulting from the decay chain in which one of the W bosons from top quark decay decays into an electron or a muon and a neutrino, and the other decays hadronically. This study searches for a resonance in the t anti t mass spectrum where the t anti t pair is reconstructed from identified decay products: jets, leptons and a neutrino. This presentation describes the search for the t anti t resonances in the l+jets final states along with the topology of the highly boosted top candidates where rather than trying to resolve the jets individually, the complete decay products is reconstructed as a single fat jet. For this analysis data collected by the ATLAS experiment in 2011 at {radical}(s)=7 TeV pp collisions are used. A description of the data-driven studies of the background as well as comparisons of the data with the expectations is shown.

  2. A search for a heavy resonance decaying to a top quark and a bottom quark with the CMS experiment

    CERN Document Server

    Sperka, David

    The standard model of particle physics can explain most measurements of elementary par- ticle properties and interactions performed to date. However, it does not naturally explain the relatively light Higgs boson mass or the existence of small neutrino masses, and has no explanation for the dark matter observed in the universe. Many extensions to the standard model have been proposed to attempt to address these questions, and several predict the existence of heavy charged gauge bosons, usually referred to as W' bosons. The Large Hadron Collider at CERN is the largest and most powerful particle accelerator in the world and offers the opportunity to search for W' bosons using the CMS experiment, a large multi-purpose particle detector. Results are presented from a search for a W' boson produced in proton-proton collisions at a center of mass energy sqrt(s) = 8 TeV and decaying into a top and a bottom quark, using a dataset collected by the CMS experiment corresponding to an integrated luminosity of 19.5 fb-1 . ...

  3. Search for Direct Top Squark Pair Production with the ATLAS Experiment and Studies of the Primary Vertex Reconstruction Performance

    CERN Document Server

    Abulaiti, Yiming

    The ATLAS detector is one of the two largest experiments installed at the Large Hadron Collider at CERN, the European Organization for Nuclear Research. During the first run, the ATLAS detector recorded data at centre of mass energies of 7 TeV and 8 TeV, enabling many precision measurements and new physics searches. One important task in ATLAS is measuring the primary vertex, the interaction point of the hardest proton-proton collision in an event. In this thesis, a study of the primary vertex reconstruction performance in data and simulated events using tt ̄ and Z events is presented. Within the statistics available, the performance in data and simulated events is found to be compatible. Motivated by the limitations of the Standard Model of particle physics, searches for supersymmetric particles are performed with the ATLAS experiment. No signal has been observed so far, and the results are used to set exclusion limits on the masses of the supersymmetric particles. As the exclusion limits are derived from a...

  4. The DarkLight Experiment: A Precision Search for New Physics at Low Energies

    CERN Document Server

    Balewski, J; Bessuille, J; Corliss, R; Cowan, R; Epstein, C; Fisher, P; Hasell, D; Ihloff, E; Kahn, Y; Kelsey, J; Milner, R; Steadman, S; Thaler, J; Tschalaer, C; Vidal, C; Benson, S; Boyce, J; Douglas, D; Evtushenko, P; Hernandez-Garcia, C; Keith, C; Tennant, C; Zhang, S; Alarcon, R; Blyth, D; Dipert, R; Ice, L; Randall, G; Dongwi, B; Kalantarians, N; Kohl, M; Liyanage, A; Nazeer, J; Garcon, M; Cervantes, R; Dehmelt, K; Deshpande, A; Feege, N; Surrow, B

    2014-01-01

    We describe the current status of the DarkLight experiment at Jefferson Laboratory. DarkLight is motivated by the possibility that a dark photon in the mass range 10 to 100 MeV/c$^2$ could couple the dark sector to the Standard Model. DarkLight will precisely measure electron proton scattering using the 100 MeV electron beam of intensity 5 mA at the Jefferson Laboratory energy recovering linac incident on a windowless gas target of molecular hydrogen. The complete final state including scattered electron, recoil proton, and e+e- pair will be detected. A phase-I experiment has been funded and is expected to take data in the next eighteen months. The complete phase-II experiment is under final design and could run within two years after phase-I is completed. The DarkLight experiment drives development of new technology for beam, target, and detector and provides a new means to carry out electron scattering experiments at low momentum transfers.

  5. Does Financial Hardship Explain Differences Between Belgian and South African Unemployed Regarding Experiences of Unemployment, Employment Commitment, and Job Search Behaviour?

    Directory of Open Access Journals (Sweden)

    Wouter Vleugels

    2013-06-01

    Full Text Available The purpose of this study was to investigate whether Belgian and South African unemployed differed regarding three psychological dimensions of unemployment: affect (experiences of unemployment, attitudes (employment commitment, and behaviour (job search intensity. Moreover, we expected country of residence to indirectly influence unemployed people's experiences, employment commitment, and job search intensity via financial hardship. A cross-sectional survey design was used to test our hypotheses. Data were sampled from unemployed people in the Brussels area in Belgium ('N' = 305, and the Potchefstroom area in South Africa ('N' = 381. The results indicated that, compared to the Belgian unemployed, the South African unemployed experienced their unemployment as more negative, were more committed towards employment and more intensively searched for work. Moreover, country of residence indirectly influenced unemployed people's experiences, employment commitment, and job search intensity via financial hardship. Some policy recommendations are suggested.

  6. In Search of the Invisible Roots: Immigrant Experiences in Jhumpa Lahiri’s Unaccustomed Earth

    Directory of Open Access Journals (Sweden)

    Rogobete Daniela

    2016-12-01

    Full Text Available This paper attempts an analysis of the metaphorical strategies Jhumpa Lahiri uses in her 2008 collection of short stories Unaccustomed Earth in order to explore and comment on the intricate relations and the complex web of feelings and resentments, longing and attachment that make up the essence of family life as shaped by the diasporic experience. In this volume, Lahiri particularly focuses on the conflicting emotions engendered by migration, on the articulation of displacement and reintegration, and on the capacity to fully assume the diasporic experience and turn it into a meaningful assertion of one’s identity.

  7. Search for νμ → νe Oscillations with the Opera Experiment

    Science.gov (United States)

    Zemskova, S. G.

    2015-06-01

    The main goal of the OPERA experiment is the direct observation of νμ → ντ oscillations in appearance mode in the quasi pure νμ CNGS beam. Profiting of the tracking capabilities of the OPERA active target it is possible to detect and reconstruct νe interactions and therefore to study the subdominant νμ → νe oscillation channel. Current results on this channel in the three-flavour mixing model are presented. The same data allow to constrain the non-standard oscillation parameters indicated by the LSND and MiniBooNE experiments.

  8. The Majorana experiment: an ultra-low background search for neutrinoless double-beta decay

    CERN Document Server

    Phillips, D G; Avignone, F T; Back, H O; Barabash, A S; Bergevin, M; Bertrand, F E; Boswell, M; Brudanin, V; Busch, M; Chan, Y -D; Christofferson, C D; Collar, J I; Combs, D C; Cooper, R J; Detwiler, J A; Doe, P J; Efremenko, Y; Egorov, V; Ejiri, H; Elliott, S R; Esterline, J; Fast, J E; Fields, N; Finnerty, P; Fraenkle, F M; Gehman, V M; Giovanetti, G K; Green, M P; Guiseppe, V E; Gusey, K; Hallin, A L; Hazama, R; Henning, R; Hime, A; Hoppe, E W; Horton, M; Howard, S; Howe, M A; Johnson, R A; Keeter, K J; Keller, C; Kidd, M F; Knecht, A; Kochetov, O; Konovalov, S I; Kouzes, R T; LaFerriere, B; LaRoque, B H; Leon, J; Leviner, L E; Loach, J C; MacMullin, S; Marino, M G; Martin, R D; Mei, D -M; Merriman, J; Miller, M L; Mizouni, L; Nomachi, M; Orrell, J L; Overman, N R; Poon, A W P; Perumpilly, G; Prior, G; Radford, D C; Rielage, K; Robertson, R G H; Ronquest, M C; Schubert, A G; Shima, T; Shirchenko, M; Snavely, K J; Steele, D; Strain, J; Thomas, K; Timkin, V; Tornow, W; Vanyushin, I; Varner, R L; Vetter, K; Vorren, K; Wilkerson, J F; Wolfe, B A; Yakushev, E; Young, A R; Yu, C -H; Yumatov, V; Zhang, C

    2011-01-01

    The observation of neutrinoless double-beta decay would resolve the Majorana nature of the neutrino and could provide information on the absolute scale of the neutrino mass. The initial phase of the Majorana experiment, known as the Demonstrator, will house 40 kg of Ge in an ultra-low background shielded environment at the 4850' level of the Sanford Underground Laboratory in Lead, SD. The objective of the Demonstrator is to determine whether a future 1-tonne experiment can achieve a background goal of one count per tonne-year in a narrow region of interest around the 76Ge neutrinoless double-beta decay peak.

  9. The MAJORANA experiment: an ultra-low background search for neutrinoless double-beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, D.; Aguayo Navarrete, Estanislao; Avignone, Frank T.; Back, Henning O.; Barabash, Alexander S.; Bergevin, M.; Bertrand, F.; Boswell, M.; Brudanin, V.; Busch, Matthew; Chan, Yuen-Dat; Christofferson, Cabot-Ann; Collar, J. I.; Combs, Dustin C.; Cooper, R. J.; Detwiler, Jason A.; Doe, Peter J.; Efremenko, Yuri; Egorov, Viatcheslav; Ejiri, H.; Elliott, Steven R.; Esterline, James H.; Fast, James E.; Fields, N.; Finnerty, P.; Fraenkle, Florian; Gehman, Victor; Giovanetti, G. K.; Green, Matthew P.; Guiseppe, Vincente; Gusey, K.; Hallin, A. L.; Hazama, R.; Henning, Reyco; Hime, Andrew; Hoppe, Eric W.; Horton, Mark; Howard, Stanley; Howe, M. A.; Johnson, R. A.; Keeter, K.; Keller, C.; Kidd, Mary; Knecht, A.; Kochetov, Oleg; Konovalov, S.; Kouzes, Richard T.; LaFerriere, Brian D.; LaRoque, B. H.; Leon, Jonathan D.; Leviner, L.; Loach, J. C.; MacMullin, S.; Marino, Michael G.; Martin, R. D.; Mei, Dong-Ming; Merriman, Jason H.; Miller, M. L.; Mizouni, Leila; Nomachi, Masaharu; Orrell, John L.; Overman, Nicole R.; Poon, Alan; Perumpilly, Gopakumar; Prior, Gersende; Radford, D. C.; Rielage, Keith; Robertson, R. G. H.; Ronquest, M. C.; Schubert, Alexis G.; Shima, T.; Shirchenko, M.; Snavely, Kyle J.; Steele, David; Strain, J.; Thomas, K.; Timkin, V.; Tornow, W.; Vanyushin, I.; Varner, R. L.; Vetter, Kai; Vorren, Kris R.; Wilkerson, J. F.; Wolfe, B. A.; Yakushev, E.; Young, A.; Yu, Chang-Hong; Yumatov, Vladimir; Zhang, C.

    2012-12-01

    The observation of neutrinoless double-beta decay would resolve the Majorana nature of the neutrino and could provide information on the absolute scale of the neutrino mass. The initial phase of the Majorana Experiment, known as the Demonstrator, will house 40 kg of Ge in an ultra-low background shielded environment at the 4850' level of the Sanford Underground Laboratory in Lead, SD. The objective of the Demonstrator is to validate whether a future 1-tonne experiment can achieve a background goal of one count per tonne-year in a narrow region of interest around the 76Ge neutrinoless double-beta decay peak.

  10. Products search through the use of semantic properties - report from the experiment at Kunstindustrimuseet

    DEFF Research Database (Denmark)

    Lenau, Torben Anker; Boelskifte, Per

    2005-01-01

    communication with regard to the semantic messages that products contain in the form of non-verbal expressions (i.e., through their shape and colour). 12 participants in groups of 2 selected exhibited products and described them verbally. Based on the verbal description, other teams were then asked to identify......In April 2004 an experiment was carried out at The Technical University of Denmark and at the Danish Arts and Craft Museum. The purpose was to explore how precise verbal communication could capture the semantic content of physical products. The experiment explored the possibilities of verbal...

  11. Keck/MOSFIRE spectroscopy of five ULX counterparts

    CERN Document Server

    Heida, M; Torres, M A P; Roberts, T P; Walton, D J; Moon, D -S; Stern, D; Harrison, F A

    2016-01-01

    We present H-band spectra of the candidate counterparts of five ULXs (two in NGC 925, two in NGC 4136, and Holmberg II X-1) obtained with Keck/MOSFIRE. The candidate counterparts of two ULXs (J022721+333500 in NGC 925 and J120922+295559 in NGC 4136) have spectra consistent with (M-type) red supergiants (RSGs). We obtained two epochs of spectroscopy of the candidate counterpart to J022721+333500, separated by 10 months, but discovered no radial velocity variations with a 2-$\\sigma$ upper limit of 40 km/s. If the RSG is the donor star of the ULX, the most likely options are that either the system is seen at low inclination (< 40$^\\circ$), or the black hole mass is less than 100 M$_\\odot$, unless the orbital period is longer than 6 years, in which case the obtained limit is not constraining. The spectrum of the counterpart to J120922+295559 shows emission lines on top of its stellar spectrum, and the remaining three counterparts do not show absorption lines that can be associated with the atmosphere of a star...

  12. Q & A Experiment to Search for Vacuum Dichroism, Pseudoscalar-Photon Interaction and Millicharged Fermions

    CERN Document Server

    Chen, S J; Ni, W T; Chen, Sheng-Jui; Mei, Hsien-Hao; Ni, Wei-Tou

    2006-01-01

    A number of experiments are underway to detect vacuum birefringence and dichroism -- PVLAS, Q & A, and BMV. Recently, PVLAS experiment has observed optical rotation in vacuum by a magnetic field (vacuum dichroism). Theoretical interpretations of this result include a possible pseudoscalar-photon interaction and the existence of millicharged fermions. Here, we report the progress and first results of Q & A (QED [quantum electrodynamics] and Axion) experiment proposed and started in 1994. A 3.5-m high-finesse (around 30,000) Fabry-Perot prototype detector extendable to 7-m has been built and tested. We use X-pendulums and automatic control schemes developed by the gravitational-wave detection community for mirror suspension and cavity control. To polarize the vacuum, we use a 2.3-T dipole permanent magnet, with 27-mm-diameter clear borehole and 0.6-m field length,. In the experiment, the magnet is rotated at 5-10 rev/s to generate time-dependent polarization signal with twice the rotation frequency. Our...

  13. Searching for Synthetic Antimicrobial Peptides: An Experiment for Organic Chemistry Students

    Science.gov (United States)

    Vasquez, Thomas E., Jr.; Saldan~a, Cristina; Muzikar, Katy A.; Mashek, Debra; Liu, Jane M.

    2016-01-01

    This laboratory experiment provides undergraduate students enrolled in organic chemistry the opportunity to design and synthesize their own peptide, which is then tested for antimicrobial activity. After reading a primary scientific paper on antimicrobial peptides, students design and synthesize their own hexapeptide that they hypothesize will…

  14. Simulated forecasts for primordial B -mode searches in ground-based experiments

    Science.gov (United States)

    Alonso, David; Dunkley, Joanna; Thorne, Ben; Næss, Sigurd

    2017-02-01

    Detecting the imprint of inflationary gravitational waves on the B -mode polarization of the cosmic microwave background (CMB) is one of the main science cases for current and next-generation CMB experiments. In this work we explore some of the challenges that ground-based facilities will have to face in order to carry out this measurement in the presence of galactic foregrounds and correlated atmospheric noise. We present forecasts for stage-3 (S3) and planned stage-4 (S4) experiments based on the analysis of simulated sky maps using a map-based Bayesian foreground-cleaning method. Our results thus consistently propagate the uncertainties on foreground parameters such as spatially varying spectral indices, as well as the bias on the measured tensor-to-scalar ratio r caused by an incorrect modeling of the foregrounds. We find that S3 and S4-like experiments should be able to put constraints on r of the order σ (r )=(0.5 - 1.0 )×10-2 and σ (r )=(0.5 - 1.0 )×10-3 respectively, assuming instrumental systematic effects are under control. We further study deviations from the fiducial foreground model, finding that, while the effects of a second polarized dust component would be minimal on both S3 and S4, a 2% polarized anomalous dust emission component would be clearly detectable by stage-4 experiments.

  15. Status of the NEXT experiment and future perspectives for HPXe-based DBD searches

    Science.gov (United States)

    Cadenas, Juan

    2014-09-01

    Neutrinos may be Majorana particles. If so, neutrinoless double beta decay processes could be observed by the next-generation bb0nu experiments. This talk will present one of the most promising ideas in the field, the use of a High Pressure Gas Xenon TPC (HPGXe) with electroluminescence gain and optical readout. A 100 kg incarnation of such a device, the NEXT-100 experiment, will start operations at the Canfranc Underground Lab in Spain in 2015. The technology can be extrapolated to 1 ton, and thus lead the exploration of the inverse hierarchy in Majorana landscape. Neutrinos may be Majorana particles. If so, neutrinoless double beta decay processes could be observed by the next-generation bb0nu experiments. This talk will present one of the most promising ideas in the field, the use of a High Pressure Gas Xenon TPC (HPGXe) with electroluminescence gain and optical readout. A 100 kg incarnation of such a device, the NEXT-100 experiment, will start operations at the Canfranc Underground Lab in Spain in 2015. The technology can be extrapolated to 1 ton, and thus lead the exploration of the inverse hierarchy in Majorana landscape. Thanks: Advanced Grant/ERC; CSIC and MINECO CONSOLIDER GREANT- CUP.

  16. Dark Matter Search in a Beam-Dump eXperiment (BDX) at Jefferson Lab

    Energy Technology Data Exchange (ETDEWEB)

    Battaglieri, M. [Univ. of Genova (Italy). National Institute for Nuclear Physics. et al

    2016-07-05

    MeV-GeV dark matter (DM) is theoretically well motivated but remarkably unexplored. This proposal presents the MeV-GeV DM discovery potential for a $\\sim$1 m$^3$ segmented CsI(Tl) scintillator detector placed downstream of the Hall A beam-dump at Jefferson Lab, receiving up to 10$^{22}$ electrons-on-target (EOT) in 285 days. This experiment (Beam-Dump eXperiment or BDX) would be sensitive to elastic DM-electron and to inelastic DM scattering at the level of 10 counts per year, reaching the limit of the neutrino irreducible background. The distinct signature of a DM interaction will be an electromagnetic shower of few hundreds of MeV, together with a reduced activity in the surrounding active veto counters. A detailed description of the DM particle $\\chi$ production in the dump and subsequent interaction in the detector has been performed by means of Monte Carlo simulations. Different approaches have been used to evaluate the expected backgrounds: the cosmogenic background has been extrapolated from the results obtained with a prototype detector running at INFN-LNS (Italy), while the beam-related background has been evaluated by GEANT4 Monte Carlo simulations. The proposed experiment will be sensitive to large regions of DM parameter space, exceeding the discovery potential of existing and planned experiments in the MeV-GeV DM mass range by up to two orders of magnitude.

  17. Searching for Synthetic Antimicrobial Peptides: An Experiment for Organic Chemistry Students

    Science.gov (United States)

    Vasquez, Thomas E., Jr.; Saldan~a, Cristina; Muzikar, Katy A.; Mashek, Debra; Liu, Jane M.

    2016-01-01

    This laboratory experiment provides undergraduate students enrolled in organic chemistry the opportunity to design and synthesize their own peptide, which is then tested for antimicrobial activity. After reading a primary scientific paper on antimicrobial peptides, students design and synthesize their own hexapeptide that they hypothesize will…

  18. Search for the Standard Model Higgs Boson in the Missing Mass Channel at the ALEPH Experiment

    CERN Document Server

    White, R R; Davies, G

    2001-01-01

    This thesis describes the official cuts-based analysis used in 1999 and 2000 to detect events of the form e+e- -> HZ -> bbnn measured with the ALEPH detector. This channel represents 15.1% of the Higgsstrahlung decay cross-section and 19% of the decays explicitly searched for by the ALEPH Higgs Task Force (HTF). The hnn channel alone can set a 95% lower limit of 102.6 GeV on the mass of the Standard Model Higgs. No evidence for a Higgs signal is seen in the data selected by this channel. Supersymmetric scenarios that predict quasi-stable sparticles are explored. Assuming stability within the detector, 95% limits can be set on the right-handed smuon, degenerate right-handed sleptons and the lightest chargino of, Mr > 96.1 GeV, $Mr > 99.55 GeV and M > 102.1 GeV respectively. The systematic effects from each channel in the Standard Model Higgs cuts stream have been calculated. The ALEPH excess is reported with the combined systematics taken as a symmetric error on this.

  19. Search for resonances decaying to top and bottom quarks with the CDF experiment

    Energy Technology Data Exchange (ETDEWEB)

    Aaltonen, Timo Antero [Univ. of Helsinki, Helsinki (Finland). et al.

    2015-08-03

    We report on a search for charged massive resonances decaying to top (t) and bottom (b) quarks in the full data set of proton-antiproton collisions at a center-of-mass energy of √s = 1.96 TeV collected by the CDF II detector at the Tevatron, corresponding to an integrated luminosity of 9.5 fb–1. No significant excess above the standard model background prediction is observed. We set 95% Bayesian credibility mass-dependent upper limits on the heavy charged-particle production cross section times branching ratio to tb. Using a standard model extension with a W' → tb and left-right-symmetric couplings as a benchmark model, we constrain the W' mass and couplings in the 300–900 GeV/c2 range. As a result, the limits presented here are the most stringent for a charged resonance with mass in the range 300–600 GeV/c2 decaying to top and bottom quarks.

  20. Search for Sporadic Enhancements of UHECR and Correlations with Cosmic Phenomena in LAAS Experiment

    Science.gov (United States)

    Ochi, N.; Iyono, A.; Konishi, T.; Nakamura, T.; Nakatsuka, T.; Ohara, S.; Ohmori, N.; Okei, K.; Saitoh, K.; Tada, J.; Takahashi, N.; Tsuji, S.; Wada, T.; Yamamoto, I.; Yamashita, Y.; LAAS Group

    2003-07-01

    The Large Area Air Shower (LAAS) group has been collecting extensive air shower (EAS) data by compact EAS arrays simultaneously operating at eleven sites in Japan. Working since 1996, a large number of EAS data have been accumulated and they are analyzed in this report. In order to find out signals from short-lived burst activities in the universe, we insp ect EAS trigger rates of short time windows and search for sporadic excess events in them. Significant events are furthermore employed to explore possible correlations with cosmic phenomena such as gamma-ray bursts, cluster events observed by AGASA and highest energy cosmic rays by AGASA and HiRes. Particularly, our EAS arrays in Okayama area, of which trigger conditions are uniformly set at 2-fold coincidence of adjacent counters since 2002, are expected to be more sensitive to such sporadic phenomena because they can be triggered by lower energy primary particles. The results using all LAAS data will be presented at the conference.

  1. Sterile neutrino search at the ILL nuclear reactor: the STEREO experiment

    CERN Document Server

    Hélaine, V

    2016-01-01

    Search for a light sterile neutrino is currently a hot topic of neutrino physics, arising from the so-called gallium and reactor anomalies, in which a deficit of neutrinos was observed with respect to expectations. Such anomalies could be explained by short distance oscillations towards a sterile state, with $\\Delta \\mathrm{m}^2\\sim$1\\,eV$^2$. The STEREO detector has been designed to track the electron anti-neutrino energy spectrum distortion from 3 to 8\\,MeV due to such a new $L/E$ oscillation, and should therefore confirm or reject the light sterile neutrino hypothesis. Electron anti-neutrinos produced by the compact reactor core of the Institut Laue-Langevin (ILL) will be detected in a 6-cells segmented volume of Gd-loaded liquid scintillator through the inverse $\\beta$-decay process. The STEREO detector is being set-up and will be commissioned in fall 2016, and start data taking soon after. In this paper we will present the final design of the detector and its status, as well as its expected sensitivity.

  2. Search for Resonances Decaying to Top and Bottom Quarks with the CDF Experiment.

    Science.gov (United States)

    Aaltonen, T; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Anzà, F; Apollinari, G; Appel, J A; Arisawa, T; Artikov, A; Asaadi, J; Ashmanskas, W; Auerbach, B; Aurisano, A; Azfar, F; Badgett, W; Bae, T; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Barria, P; Bartos, P; Bauce, M; Bedeschi, F; Behari, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Bhatti, A; Bianchi, L; Bland, K R; Blumenfeld, B; Bocci, A; Bodek, A; Bortoletto, D; Boudreau, J; Boveia, A; Brigliadori, L; Bromberg, C; Brucken, E; Budagov, J; Budd, H S; Burkett, K; Busetto, G; Bussey, P; Butti, P; Buzatu, A; Calamba, A; Camarda, S; Campanelli, M; Canelli, F; Carls, B; Carlsmith, D; Carosi, R; Carrillo, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavaliere, V; Cerri, A; Cerrito, L; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Cho, K; Chokheli, D; Clark, A; Clarke, C; Convery, M E; Conway, J; Corbo, M; Cordelli, M; Cox, C A; Cox, D J; Cremonesi, M; Cruz, D; Cuevas, J; Culbertson, R; d'Ascenzo, N; Datta, M; de Barbaro, P; Demortier, L; Deninno, M; D'Errico, M; Devoto, F; Di Canto, A; Di Ruzza, B; Dittmann, J R; Donati, S; D'Onofrio, M; Dorigo, M; Driutti, A; Ebina, K; Edgar, R; Elagin, A; Erbacher, R; Errede, S; Esham, B; Farrington, S; Fernández Ramos, J P; Field, R; Flanagan, G; Forrest, R; Franklin, M; Freeman, J C; Frisch, H; Funakoshi, Y; Galloni, C; Garfinkel, A F; Garosi, P; Gerberich, H; Gerchtein, E; Giagu, S; Giakoumopoulou, V; Gibson, K; Ginsburg, C M; Giokaris, N; Giromini, P; Glagolev, V; Glenzinski, D; Gold, M; Goldin, D; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González López, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gramellini, E; Grosso-Pilcher, C; Group, R C; Guimaraes da Costa, J; Hahn, S R; Han, J Y; Happacher, F; Hara, K; Hare, M; Harr, R F; Harrington-Taber, T; Hatakeyama, K; Hays, C; Heinrich, J; Herndon, M; Hocker, A; Hong, Z; Hopkins, W; Hou, S; Hughes, R E; Husemann, U; Hussein, M; Huston, J; Introzzi, G; Iori, M; Ivanov, A; James, E; Jang, D; Jayatilaka, B; Jeon, E J; Jindariani, S; Jones, M; Joo, K K; Jun, S Y; Junk, T R; Kambeitz, M; Kamon, T; Karchin, P E; Kasmi, A; Kato, Y; Ketchum, W; Keung, J; Kilminster, B; Kim, D H; Kim, H S; Kim, J E; Kim, M J; Kim, S H; Kim, S B; Kim, Y J; Kim, Y K; Kimura, N; Kirby, M; Knoepfel, K; Kondo, K; Kong, D J; Konigsberg, J; Kotwal, A V; Kreps, M; Kroll, J; Kruse, M; Kuhr, T; Kurata, M; Laasanen, A T; Lammel, S; Lancaster, M; Lannon, K; Latino, G; Lee, H S; Lee, J S; Leo, S; Leone, S; Lewis, J D; Limosani, A; Lipeles, E; Lister, A; Liu, H; Liu, Q; Liu, T; Lockwitz, S; Loginov, A; Lucchesi, D; Lucà, A; Lueck, J; Lujan, P; Lukens, P; Lungu, G; Lys, J; Lysak, R; Madrak, R; Maestro, P; Malik, S; Manca, G; Manousakis-Katsikakis, A; Marchese, L; Margaroli, F; Marino, P; Matera, K; Mattson, M E; Mazzacane, A; Mazzanti, P; McNulty, R; Mehta, A; Mehtala, P; Mesropian, C; Miao, T; Mietlicki, D; Mitra, A; Miyake, H; Moed, S; Moggi, N; Moon, C S; Moore, R; Morello, M J; Mukherjee, A; Muller, Th; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Naganoma, J; Nakano, I; Napier, A; Nett, J; Neu, C; Nigmanov, T; Nodulman, L; Noh, S Y; Norniella, O; Oakes, L; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Orava, R; Ortolan, L; Pagliarone, C; Palencia, E; Palni, P; Papadimitriou, V; Parker, W; Pauletta, G; Paulini, M; Paus, C; Phillips, T J; Piacentino, G; Pianori, E; Pilot, J; Pitts, K; Plager, C; Pondrom, L; Poprocki, S; Potamianos, K; Pranko, A; Prokoshin, F; Ptohos, F; Punzi, G; Redondo Fernández, I; Renton, P; Rescigno, M; Rimondi, F; Ristori, L; Robson, A; Rodriguez, T; Rolli, S; Ronzani, M; Roser, R; Rosner, J L; Ruffini, F; Ruiz, A; Russ, J; Rusu, V; Sakumoto, W K; Sakurai, Y; Santi, L; Sato, K; Saveliev, V; Savoy-Navarro, A; Schlabach, P; Schmidt, E E; Schwarz, T; Scodellaro, L; Scuri, F; Seidel, S; Seiya, Y; Semenov, A; Sforza, F; Shalhout, S Z; Shears, T; Shepard, P F; Shimojima, M; Shochet, M; Shreyber-Tecker, I; Simonenko, A; Sliwa, K; Smith, J R; Snider, F D; Song, H; Sorin, V; St Denis, R; Stancari, M; Stentz, D; Strologas, J; Sudo, Y; Sukhanov, A; Suslov, I; Takemasa, K; Takeuchi, Y; Tang, J; Tecchio, M; Teng, P K; Thom, J; Thomson, E; Thukral, V; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Totaro, P; Trovato, M; Ukegawa, F; Uozumi, S; Vázquez, F; Velev, G; Vellidis, C; Vernieri, C; Vidal, M; Vilar, R; Vizán, J; Vogel, M; Volpi, G; Wagner, P; Wallny, R; Wang, S M; Waters, D; Wester, W C; Whiteson, D; Wicklund, A B; Wilbur, S; Williams, H H; Wilson, J S; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, H; Wright, T; Wu, X; Wu, Z; Yamamoto, K; Yamato, D; Yang, T; Yang, U K; Yang, Y C; Yao, W-M; Yeh, G P; Yi, K; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Zanetti, A M; Zeng, Y; Zhou, C; Zucchelli, S

    2015-08-01

    We report on a search for charged massive resonances decaying to top (t) and bottom (b) quarks in the full data set of proton-antiproton collisions at a center-of-mass energy of √[s]=1.96  TeV collected by the CDF II detector at the Tevatron, corresponding to an integrated luminosity of 9.5  fb(-1). No significant excess above the standard model background prediction is observed. We set 95% Bayesian credibility mass-dependent upper limits on the heavy charged-particle production cross section times branching ratio to tb. Using a standard model extension with a W'→tb and left-right-symmetric couplings as a benchmark model, we constrain the W' mass and couplings in the 300-900  GeV/c(2) range. The limits presented here are the most stringent for a charged resonance with mass in the range 300-600  GeV/c(2) decaying to top and bottom quarks.

  3. Search for Resonances Decaying to Top and Bottom Quarks with the CDF Experiment

    Science.gov (United States)

    Aaltonen, T.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Anzà, F.; Apollinari, G.; Appel, J. A.; Arisawa, T.; Artikov, A.; Asaadi, J.; Ashmanskas, W.; Auerbach, B.; Aurisano, A.; Azfar, F.; Badgett, W.; Bae, T.; Barbaro-Galtieri, A.; Barnes, V. E.; Barnett, B. A.; Barria, P.; Bartos, P.; Bauce, M.; Bedeschi, F.; Behari, S.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Beretvas, A.; Bhatti, A.; Bianchi, L.; Bland, K. R.; Blumenfeld, B.; Bocci, A.; Bodek, A.; Bortoletto, D.; Boudreau, J.; Boveia, A.; Brigliadori, L.; Bromberg, C.; Brucken, E.; Budagov, J.; Budd, H. S.; Burkett, K.; Busetto, G.; Bussey, P.; Butti, P.; Buzatu, A.; Calamba, A.; Camarda, S.; Campanelli, M.; Canelli, F.; Carls, B.; Carlsmith, D.; Carosi, R.; Carrillo, S.; Casal, B.; Casarsa, M.; Castro, A.; Catastini, P.; Cauz, D.; Cavaliere, V.; Cerri, A.; Cerrito, L.; Chen, Y. C.; Chertok, M.; Chiarelli, G.; Chlachidze, G.; Cho, K.; Chokheli, D.; Clark, A.; Clarke, C.; Convery, M. E.; Conway, J.; Corbo, M.; Cordelli, M.; Cox, C. A.; Cox, D. J.; Cremonesi, M.; Cruz, D.; Cuevas, J.; Culbertson, R.; d'Ascenzo, N.; Datta, M.; de Barbaro, P.; Demortier, L.; Deninno, M.; D'Errico, M.; Devoto, F.; Di Canto, A.; Di Ruzza, B.; Dittmann, J. R.; Donati, S.; D'Onofrio, M.; Dorigo, M.; Driutti, A.; Ebina, K.; Edgar, R.; Elagin, A.; Erbacher, R.; Errede, S.; Esham, B.; Farrington, S.; Fernández Ramos, J. P.; Field, R.; Flanagan, G.; Forrest, R.; Franklin, M.; Freeman, J. C.; Frisch, H.; Funakoshi, Y.; Galloni, C.; Garfinkel, A. F.; Garosi, P.; Gerberich, H.; Gerchtein, E.; Giagu, S.; Giakoumopoulou, V.; Gibson, K.; Ginsburg, C. M.; Giokaris, N.; Giromini, P.; Glagolev, V.; Glenzinski, D.; Gold, M.; Goldin, D.; Golossanov, A.; Gomez, G.; Gomez-Ceballos, G.; Goncharov, M.; González López, O.; Gorelov, I.; Goshaw, A. T.; Goulianos, K.; Gramellini, E.; Grosso-Pilcher, C.; Group, R. C.; Guimaraes da Costa, J.; Hahn, S. R.; Han, J. Y.; Happacher, F.; Hara, K.; Hare, M.; Harr, R. F.; Harrington-Taber, T.; Hatakeyama, K.; Hays, C.; Heinrich, J.; Herndon, M.; Hocker, A.; Hong, Z.; Hopkins, W.; Hou, S.; Hughes, R. E.; Husemann, U.; Hussein, M.; Huston, J.; Introzzi, G.; Iori, M.; Ivanov, A.; James, E.; Jang, D.; Jayatilaka, B.; Jeon, E. J.; Jindariani, S.; Jones, M.; Joo, K. K.; Jun, S. Y.; Junk, T. R.; Kambeitz, M.; Kamon, T.; Karchin, P. E.; Kasmi, A.; Kato, Y.; Ketchum, W.; Keung, J.; Kilminster, B.; Kim, D. H.; Kim, H. S.; Kim, J. E.; Kim, M. J.; Kim, S. H.; Kim, S. B.; Kim, Y. J.; Kim, Y. K.; Kimura, N.; Kirby, M.; Knoepfel, K.; Kondo, K.; Kong, D. J.; Konigsberg, J.; Kotwal, A. V.; Kreps, M.; Kroll, J.; Kruse, M.; Kuhr, T.; Kurata, M.; Laasanen, A. T.; Lammel, S.; Lancaster, M.; Lannon, K.; Latino, G.; Lee, H. S.; Lee, J. S.; Leo, S.; Leone, S.; Lewis, J. D.; Limosani, A.; Lipeles, E.; Lister, A.; Liu, H.; Liu, Q.; Liu, T.; Lockwitz, S.; Loginov, A.; Lucchesi, D.; Lucà, A.; Lueck, J.; Lujan, P.; Lukens, P.; Lungu, G.; Lys, J.; Lysak, R.; Madrak, R.; Maestro, P.; Malik, S.; Manca, G.; Manousakis-Katsikakis, A.; Marchese, L.; Margaroli, F.; Marino, P.; Matera, K.; Mattson, M. E.; Mazzacane, A.; Mazzanti, P.; McNulty, R.; Mehta, A.; Mehtala, P.; Mesropian, C.; Miao, T.; Mietlicki, D.; Mitra, A.; Miyake, H.; Moed, S.; Moggi, N.; Moon, C. S.; Moore, R.; Morello, M. J.; Mukherjee, A.; Muller, Th.; Murat, P.; Mussini, M.; Nachtman, J.; Nagai, Y.; Naganoma, J.; Nakano, I.; Napier, A.; Nett, J.; Neu, C.; Nigmanov, T.; Nodulman, L.; Noh, S. Y.; Norniella, O.; Oakes, L.; Oh, S. H.; Oh, Y. D.; Oksuzian, I.; Okusawa, T.; Orava, R.; Ortolan, L.; Pagliarone, C.; Palencia, E.; Palni, P.; Papadimitriou, V.; Parker, W.; Pauletta, G.; Paulini, M.; Paus, C.; Phillips, T. J.; Piacentino, G.; Pianori, E.; Pilot, J.; Pitts, K.; Plager, C.; Pondrom, L.; Poprocki, S.; Potamianos, K.; Pranko, A.; Prokoshin, F.; Ptohos, F.; Punzi, G.; Redondo Fernández, I.; Renton, P.; Rescigno, M.; Rimondi, F.; Ristori, L.; Robson, A.; Rodriguez, T.; Rolli, S.; Ronzani, M.; Roser, R.; Rosner, J. L.; Ruffini, F.; Ruiz, A.; Russ, J.; Rusu, V.; Sakumoto, W. K.; Sakurai, Y.; Santi, L.; Sato, K.; Saveliev, V.; Savoy-Navarro, A.; Schlabach, P.; Schmidt, E. E.; Schwarz, T.; Scodellaro, L.; Scuri, F.; Seidel, S.; Seiya, Y.; Semenov, A.; Sforza, F.; Shalhout, S. Z.; Shears, T.; Shepard, P. F.; Shimojima, M.; Shochet, M.; Shreyber-Tecker, I.; Simonenko, A.; Sliwa, K.; Smith, J. R.; Snider, F. D.; Song, H.; Sorin, V.; St. Denis, R.; Stancari, M.; Stentz, D.; Strologas, J.; Sudo, Y.; Sukhanov, A.; Suslov, I.; Takemasa, K.; Takeuchi, Y.; Tang, J.; Tecchio, M.; Teng, P. K.; Thom, J.; Thomson, E.; Thukral, V.; Toback, D.; Tokar, S.; Tollefson, K.; Tomura, T.; Tonelli, D.; Torre, S.; Torretta, D.; Totaro, P.; Trovato, M.; Ukegawa, F.; Uozumi, S.; Vázquez, F.; Velev, G.; Vellidis, C.; Vernieri, C.; Vidal, M.; Vilar, R.; Vizán, J.; Vogel, M.; Volpi, G.; Wagner, P.; Wallny, R.; Wang, S. M.; Waters, D.; Wester, W. C.; Whiteson, D.; Wicklund, A. B.; Wilbur, S.; Williams, H. H.; Wilson, J. S.; Wilson, P.; Winer, B. L.; Wittich, P.; Wolbers, S.; Wolfe, H.; Wright, T.; Wu, X.; Wu, Z.; Yamamoto, K.; Yamato, D.; Yang, T.; Yang, U. K.; Yang, Y. C.; Yao, W.-M.; Yeh, G. P.; Yi, K.; Yoh, J.; Yorita, K.; Yoshida, T.; Yu, G. B.; Yu, I.; Zanetti, A. M.; Zeng, Y.; Zhou, C.; Zucchelli, S.; CDF Collaboration

    2015-08-01

    We report on a search for charged massive resonances decaying to top (t ) and bottom (b ) quarks in the full data set of proton-antiproton collisions at a center-of-mass energy of √{s }=1.96 TeV collected by the CDF II detector at the Tevatron, corresponding to an integrated luminosity of 9.5 fb-1 . No significant excess above the standard model background prediction is observed. We set 95% Bayesian credibility mass-dependent upper limits on the heavy charged-particle production cross section times branching ratio to t b . Using a standard model extension with a W'→t b and left-right-symmetric couplings as a benchmark model, we constrain the W' mass and couplings in the 300 - 900 GeV /c2 range. The limits presented here are the most stringent for a charged resonance with mass in the range 300 - 600 GeV /c2 decaying to top and bottom quarks.

  4. A Search for New Resonances with the Dijet Angular Ratio Using the Compact Muon Solenoid Experiment

    Energy Technology Data Exchange (ETDEWEB)

    John, Jason Michael [Boston Univ., MA (United States)

    2012-01-01

    A search for dijet resonances is performed using 2.2 fb$^{-1}$ of proton-proton collision data at $\\sqrt{s}$ = 7 TeV recorded by the CMS detector at CERN. The study is based on the dijet angular ratio, the ratio of the number of events with the two leading jets having pseudorapidity difference |delta eta| < 1.3 to the number of events with 1.3 < |delta eta| < 3.0. Models of new resonances which decay into two jets typically predict dijet angular distributions and hence, values of the dijet angular ratio which differ from standard model processes. We thus use the measurement of the angular ratio as a function of mass to set limits on the cross sections of new spin -1/2 quark-gluon resonances. We exclude excited quarks of mass less than 3.2 TeV at 95% confidence level, where a limit of 2.8 TeV is expected.

  5. A Search for New Resonances with the Dijet Angular Ratio Using the Compact Muon Solenoid Experiment

    CERN Document Server

    St John, Jason Michael; Harris, Rob

    A search for dijet resonances is performed using 2.2 fb$^{-1}$ of proton-proton collision data at $\\sqrt{s}$ = 7 TeV recorded by the CMS detector at CERN. The study is based on the dijet angular ratio, the ratio of the number of events with the two leading jets having pseudorapidity difference |delta eta| < 1.3 to the number of events with 1.3 < |delta eta| < 3.0. Models of new resonances which decay into two jets typically predict dijet angular distributions and hence, values of the dijet angular ratio which differ from standard model processes. We thus use the measurement of the angular ratio as a function of mass to set limits on the cross sections of new spin -1/2 quark-gluon resonances. We exclude excited quarks of mass less than 3.2 TeV at 95% confidence level, where a limit of 2.8 TeV is expected.

  6. Search for Resonances Decaying to Top and Bottom Quarks with the CDF Experiment

    CERN Document Server

    Aaltonen, Timo Antero; Amerio, Silvia; Amidei, Dante E; Anastassov, Anton Iankov; Annovi, Alberto; Antos, Jaroslav; Anza, Fabio; Apollinari, Giorgio; Appel, Jeffrey A; Arisawa, Tetsuo; Artikov, Akram Muzafarovich; Asaadi, Jonathan A; Ashmanskas, William Joseph; Auerbach, Benjamin; Aurisano, Adam J; Azfar, Farrukh A; Badgett, William Farris; Bae, Taegil; Barbaro-Galtieri, Angela; Barnes, Virgil E; Barnett, Bruce Arnold; Barria, Patrizia; Bartos, Pavol; Bauce, Matteo; Bedeschi, Franco; Behari, Satyajit; Bellettini, Giorgio; Bellinger, James Nugent; Benjamin, Douglas P; Beretvas, Andrew F; Bhatti, Anwar Ahmad; Bianchi, Ludovico; Bland, Karen Renee; Blumenfeld, Barry J; Bocci, Andrea; Bodek, Arie; Bortoletto, Daniela; Boudreau, Joseph Francis; Boveia, Antonio; Brigliadori, Luca; Bromberg, Carl Michael; Brucken, Erik; Budagov, Ioulian A; Budd, Howard Scott; Burkett, Kevin Alan; Busetto, Giovanni; Bussey, Peter John; Butti, Pierfrancesco; Buzatu, Adrian; Calamba, Aristotle; Camarda, Stefano; Campanelli, Mario; Canelli, Florencia; Carls, Benjamin; Carlsmith, Duncan L; Carosi, Roberto; Carrillo Moreno, Salvador; Casal Larana, Bruno; Casarsa, Massimo; Castro, Andrea; Catastini, Pierluigi; Cauz, Diego; Cavaliere, Viviana; Cerri, Alessandro; Cerrito, Lucio; Chen, Yen-Chu; Chertok, Maxwell Benjamin; Chiarelli, Giorgio; Chlachidze, Gouram; Cho, Kihyeon; Chokheli, Davit; Clark, Allan Geoffrey; Clarke, Christopher Joseph; Convery, Mary Elizabeth; Conway, John Stephen; Corbo, Matteo; Cordelli, Marco; Cox, Charles Alexander; Cox, David Jeremy; Cremonesi, Matteo; Cruz Alonso, Daniel; Cuevas Maestro, Javier; Culbertson, Raymond Lloyd; D'Ascenzo, Nicola; Datta, Mousumi; de Barbaro, Pawel; Demortier, Luc M; Deninno, Maria Maddalena; D'Errico, Maria; Devoto, Francesco; Di Canto, Angelo; Di Ruzza, Benedetto; Dittmann, Jay Richard; Donati, Simone; D'Onofrio, Monica; Dorigo, Mirco; Driutti, Anna; Ebina, Koji; Edgar, Ryan Christopher; Elagin, Andrey L; Erbacher, Robin D; Errede, Steven Michael; Esham, Benjamin; Farrington, Sinead Marie; Fernández Ramos, Juan Pablo; Field, Richard D; Flanagan, Gene U; Forrest, Robert David; Franklin, Melissa EB; Freeman, John Christian; Frisch, Henry J; Funakoshi, Yujiro; Galloni, Camilla; Garfinkel, Arthur F; Garosi, Paola; Gerberich, Heather Kay; Gerchtein, Elena A; Giagu, Stefano; Giakoumopoulou, Viktoria Athina; Gibson, Karen Ruth; Ginsburg, Camille Marie; Giokaris, Nikos D; Giromini, Paolo; Glagolev, Vladimir; Glenzinski, Douglas Andrew; Gold, Michael S; Goldin, Daniel; Golossanov, Alexander; Gomez, Gervasio; Gomez-Ceballos, Guillelmo; Goncharov, Maxim T; González López, Oscar; Gorelov, Igor V; Goshaw, Alfred T; Goulianos, Konstantin A; Gramellini, Elena; Grosso-Pilcher, Carla; Group, Robert Craig; Guimaraes da Costa, Joao; Hahn, Stephen R; Han, Ji-Yeon; Happacher, Fabio; Hara, Kazuhiko; Hare, Matthew Frederick; Harr, Robert Francis; Harrington-Taber, Timothy; Hatakeyama, Kenichi; Hays, Christopher Paul; Heinrich, Joel G; Herndon, Matthew Fairbanks; Hocker, James Andrew; Hong, Ziqing; Hopkins, Walter Howard; Hou, Suen Ray; Hughes, Richard Edward; Husemann, Ulrich; Hussein, Mohammad; Huston, Joey Walter; Introzzi, Gianluca; Iori, Maurizio; Ivanov, Andrew Gennadievich; James, Eric B; Jang, Dongwook; Jayatilaka, Bodhitha Anjalike; Jeon, Eun-Ju; Jindariani, Sergo Robert; Jones, Matthew T; Joo, Kyung Kwang; Jun, Soon Yung; Junk, Thomas R; Kambeitz, Manuel; Kamon, Teruki; Karchin, Paul Edmund; Kasmi, Azeddine; Kato, Yukihiro; Ketchum, Wesley Robert; Keung, Justin Kien; Kilminster, Benjamin John; Kim, DongHee; Kim, Hyunsoo; Kim, Jieun; Kim, Min Jeong; Kim, Shin-Hong; Kim, Soo Bong; Kim, Young-Jin; Kim, Young-Kee; Kimura, Naoki; Kirby, Michael H; Knoepfel, Kyle James; Kondo, Kunitaka; Kong, Dae Jung; Konigsberg, Jacobo; Kotwal, Ashutosh Vijay; Kreps, Michal; Kroll, IJoseph; Kruse, Mark Charles; Kuhr, Thomas; Kurata, Masakazu; Laasanen, Alvin Toivo; Lammel, Stephan; Lancaster, Mark; Lannon, Kevin Patrick; Latino, Giuseppe; Lee, Hyun Su; Lee, Jaison; Leo, Sabato; Leone, Sandra; Lewis, Jonathan D; Limosani, Antonio; Lipeles, Elliot David; Lister, Alison; Liu, Hao; Liu, Qiuguang; Liu, Tiehui Ted; Lockwitz, Sarah E; Loginov, Andrey Borisovich; Lucchesi, Donatella; Lucà, Alessandra; Lueck, Jan; Lujan, Paul Joseph; Lukens, Patrick Thomas; Lungu, Gheorghe; Lys, Jeremy E; Lysak, Roman; Madrak, Robyn Leigh; Maestro, Paolo; Malik, Sarah Alam; Manca, Giulia; Manousakis-Katsikakis, Arkadios; Marchese, Luigi Marchese; Margaroli, Fabrizio; Marino, Christopher Phillip; Matera, Keith; Mattson, Mark Edward; Mazzacane, Anna; Mazzanti, Paolo; McNulty, Ronan; Mehta, Andrew; Mehtala, Petteri; Mesropian, Christina; Miao, Ting; Mietlicki, David John; Mitra, Ankush; Miyake, Hideki; Moed, Shulamit; Moggi, Niccolo; Moon, Chang-Seong; Moore, Ronald Scott; Morello, Michael Joseph; Mukherjee, Aseet; Muller, Thomas; Murat, Pavel A; Mussini, Manuel; Nachtman, Jane Marie; Nagai, Yoshikazu; Naganoma, Junji; Nakano, Itsuo; Napier, Austin; Nett, Jason Michael; Neu, Christopher Carl; Nigmanov, Turgun S; Nodulman, Lawrence J; Noh, Seoyoung; Norniella Francisco, Olga; Oakes, Louise Beth; Oh, Seog Hwan; Oh, Young-do; Oksuzian, Iuri Artur; Okusawa, Toru; Orava, Risto Olavi; Ortolan, Lorenzo; Pagliarone, Carmine Elvezio; Palencia, Jose Enrique; Palni, Prabhakar; Papadimitriou, Vaia; Parker, William Chesluk; Pauletta, Giovanni; Paulini, Manfred; Paus, Christoph Maria Ernst; Phillips, Thomas J; Piacentino, Giovanni M; Pianori, Elisabetta; Pilot, Justin Robert; Pitts, Kevin T; Plager, Charles; Pondrom, Lee G; Poprocki, Stephen; Potamianos, Karolos Jozef; Pranko, Aliaksandr Pavlovich; Prokoshin, Fedor; Ptohos, Fotios K; Punzi, Giovanni; Redondo Fernández, Ignacio; Renton, Peter B; Rescigno, Marco; Rimondi, Franco; Ristori, Luciano; Robson, Aidan; Rodriguez, Tatiana Isabel; Rolli, Simona; Ronzani, Manfredi; Roser, Robert Martin; Rosner, Jonathan L; Ruffini, Fabrizio; Ruiz Jimeno, Alberto; Russ, James S; Rusu, Vadim Liviu; Sakumoto, Willis Kazuo; Sakurai, Yuki; Santi, Lorenzo; Sato, Koji; Saveliev, Valeri; Savoy-Navarro, Aurore; Schlabach, Philip; Schmidt, Eugene E; Schwarz, Thomas A; Scodellaro, Luca; Scuri, Fabrizio; Seidel, Sally C; Seiya, Yoshihiro; Semenov, Alexei; Sforza, Federico; Shalhout, Shalhout Zaki; Shears, Tara G; Shepard, Paul F; Shimojima, Makoto; Shochet, Melvyn J; Shreyber-Tecker, Irina; Simonenko, Alexander V; Sliwa, Krzysztof Jan; Smith, John Rodgers; Snider, Frederick Douglas; Song, Hao; Sorin, Maria Veronica; St Denis, Richard Dante; Stancari, Michelle Dawn; Stentz, Dale James; Strologas, John; Sudo, Yuji; Sukhanov, Alexander I; Suslov, Igor M; Takemasa, Ken-ichi; Takeuchi, Yuji; Tang, Jian; Tecchio, Monica; Teng, Ping-Kun; Thom, Julia; Thomson, Evelyn Jean; Thukral, Vaikunth; Toback, David A; Tokar, Stanislav; Tollefson, Kirsten Anne; Tomura, Tomonobu; Tonelli, Diego; Torre, Stefano; Torretta, Donatella; Totaro, Pierluigi; Trovato, Marco; Ukegawa, Fumihiko; Uozumi, Satoru; Velev, Gueorgui; Vellidis, Konstantinos; Vernieri, Caterina; Vidal Marono, Miguel; Vilar Cortabitarte, Rocio; Vizán Garcia, Jesus Manuel; Vogel, Marcelo; Volpi, Guido; Vázquez-Valencia, Elsa Fabiola; Wagner, Peter; Wallny, Rainer S; Wang, Song-Ming; Waters, David S; Wester, William Carl; Whiteson, Daniel O; Wicklund, Arthur Barry; Wilbur, Scott; Williams, Hugh H; Wilson, Jonathan Samuel; Wilson, Peter James; Winer, Brian L; Wittich, Peter; Wolbers, Stephen A; Wolfe, Homer; Wright, Thomas Roland; Wu, Xin; Wu, Zhenbin; Yamamoto, Kazuhiro; Yamato, Daisuke; Yang, Tingjun; Yang, Un-Ki; Yang, Yu Chul; Yao, Wei-Ming; Yeh, Gong Ping; Yi, Kai; Yoh, John; Yorita, Kohei; Yoshida, Takuo; Yu, Geum Bong; Yu, Intae; Zanetti, Anna Maria; Zeng, Yu; Zhou, Chen; Zucchelli, Stefano

    2015-01-01

    We report on a search for charged massive resonances decaying to top ($t$) and bottom ($b$) quarks in the full data set of proton-antiproton collisions at center-of-mass energy of $\\sqrt{s} = 1.96$ TeV collected by the CDF~II detector at the Tevatron, corresponding to an integrated luminosity of 9.5 $fb^{-1}$. No significant excess above the standard model (SM) background prediction is observed. We set 95% Bayesian credibility mass-dependent upper limits on the heavy charged particle production cross section times branching ratio to $t b$. Using a SM extension with a $W^{\\prime}$ and left-right-symmetric couplings as a benchmark model, we constrain the $W^{\\prime}$ mass and couplings in the 300 to 900 GeV/$c^2$ range. The limits presented here are the most stringent for a charged resonance with mass in the range 300 -- 600 GeV/$c^2$ decaying to top and bottom quarks.

  7. The MoEDAL experiment at the LHC. Searching beyond the standard model

    Directory of Open Access Journals (Sweden)

    Pinfold James L.

    2016-01-01

    The innovative MoEDAL detector employs unconventional methodologies tuned to the prospect of discovery physics. The largely passive MoEDAL detector, deployed at Point 8 on the LHC ring, has a dual nature. First, it acts like a giant camera, comprised of nuclear track detectors - analyzed offline by ultra fast scanning microscopes - sensitive only to new physics. Second, it is uniquely able to trap the particle messengers of physics beyond the Standard Model for further study. MoEDAL’s radiation environment is monitored by a state-of-the-art real-time TimePix pixel detector array. A new MoEDAL sub-detector to extend MoEDAL’s reach to millicharged, minimally ionizing, particles (MMIPs is under study Finally we shall describe the next step for MoEDAL called Cosmic MoEDAL, where we define a very large high altitude array to take the search for highly ionizing avatars of new physics to higher masses that are available from the cosmos.

  8. Search for Resonances Decaying to Top and Bottom Quarks with the CDF Experiment

    CERN Document Server

    Aaltonen, Timo Antero; Amidei, Dante E; Anastassov, Anton Iankov; Annovi, Alberto; Antos, Jaroslav; Anza, Fabio; Apollinari, Giorgio; Appel, Jeffrey A; Arisawa, Tetsuo; Artikov, Akram Muzafarovich; Asaadi, Jonathan A; Ashmanskas, William Joseph; Auerbach, Benjamin; Aurisano, Adam J; Azfar, Farrukh A; Badgett, William Farris; Bae, Taegil; Barbaro-Galtieri, Angela; Barnes, Virgil E; Barnett, Bruce Arnold; Barria, Patrizia; Bartos, Pavol; Bauce, Matteo; Bedeschi, Franco; Behari, Satyajit; Bellettini, Giorgio; Bellinger, James Nugent; Benjamin, Douglas P; Beretvas, Andrew F; Bhatti, Anwar Ahmad; Bianchi, Ludovico; Bland, Karen Renee; Blumenfeld, Barry J; Bocci, Andrea; Bodek, Arie; Bortoletto, Daniela; Boudreau, Joseph Francis; Boveia, Antonio; Brigliadori, Luca; Bromberg, Carl Michael; Brucken, Erik; Budagov, Ioulian A; Budd, Howard Scott; Burkett, Kevin Alan; Busetto, Giovanni; Bussey, Peter John; Butti, Pierfrancesco; Buzatu, Adrian; Calamba, Aristotle; Camarda, Stefano; Campanelli, Mario; Canelli, Florencia; Carls, Benjamin; Carlsmith, Duncan L; Carosi, Roberto; Carrillo Moreno, Salvador; Casal Larana, Bruno; Casarsa, Massimo; Castro, Andrea; Catastini, Pierluigi; Cauz, Diego; Cavaliere, Viviana; Cerri, Alessandro; Cerrito, Lucio; Chen, Yen-Chu; Chertok, Maxwell Benjamin; Chiarelli, Giorgio; Chlachidze, Gouram; Cho, Kihyeon; Chokheli, Davit; Clark, Allan Geoffrey; Clarke, Christopher Joseph; Convery, Mary Elizabeth; Conway, John Stephen; Corbo, Matteo; Cordelli, Marco; Cox, Charles Alexander; Cox, David Jeremy; Cremonesi, Matteo; Cruz Alonso, Daniel; Cuevas Maestro, Javier; Culbertson, Raymond Lloyd; D'Ascenzo, Nicola; Datta, Mousumi; de Barbaro, Pawel; Demortier, Luc M; Deninno, Maria Maddalena; D'Errico, Maria; Devoto, Francesco; Di Canto, Angelo; Di Ruzza, Benedetto; Dittmann, Jay Richard; Donati, Simone; D'Onofrio, Monica; Dorigo, Mirco; Driutti, Anna; Ebina, Koji; Edgar, Ryan Christopher; Elagin, Andrey L; Erbacher, Robin D; Errede, Steven Michael; Esham, Benjamin; Farrington, Sinead Marie; Fernández Ramos, Juan Pablo; Field, Richard D; Flanagan, Gene U; Forrest, Robert David; Franklin, Melissa EB; Freeman, John Christian; Frisch, Henry J; Funakoshi, Yujiro; Galloni, Camilla; Garfinkel, Arthur F; Garosi, Paola; Gerberich, Heather Kay; Gerchtein, Elena A; Giagu, Stefano; Giakoumopoulou, Viktoria Athina; Gibson, Karen Ruth; Ginsburg, Camille Marie; Giokaris, Nikos D; Giromini, Paolo; Glagolev, Vladimir; Glenzinski, Douglas Andrew; Gold, Michael S; Goldin, Daniel; Golossanov, Alexander; Gomez, Gervasio; Gomez-Ceballos, Guillelmo; Goncharov, Maxim T; González López, Oscar; Gorelov, Igor V; Goshaw, Alfred T; Goulianos, Konstantin A; Gramellini, Elena; Grosso-Pilcher, Carla; Group, Robert Craig; Guimaraes da Costa, Joao; Hahn, Stephen R; Han, Ji-Yeon; Happacher, Fabio; Hara, Kazuhiko; Hare, Matthew Frederick; Harr, Robert Francis; Harrington-Taber, Timothy; Hatakeyama, Kenichi; Hays, Christopher Paul; Heinrich, Joel G; Herndon, Matthew Fairbanks; Hocker, James Andrew; Hong, Ziqing; Hopkins, Walter Howard; Hou, Suen Ray; Hughes, Richard Edward; Husemann, Ulrich; Hussein, Mohammad; Huston, Joey Walter; Introzzi, Gianluca; Iori, Maurizio; Ivanov, Andrew Gennadievich; James, Eric B; Jang, Dongwook; Jayatilaka, Bodhitha Anjalike; Jeon, Eun-Ju; Jindariani, Sergo Robert; Jones, Matthew T; Joo, Kyung Kwang; Jun, Soon Yung; Junk, Thomas R; Kambeitz, Manuel; Kamon, Teruki; Karchin, Paul Edmund; Kasmi, Azeddine; Kato, Yukihiro; Ketchum, Wesley Robert; Keung, Justin Kien; Kilminster, Benjamin John; Kim, DongHee; Kim, Hyunsoo; Kim, Jieun; Kim, Min Jeong; Kim, Shin-Hong; Kim, Soo Bong; Kim, Young-Jin; Kim, Young-Kee; Kimura, Naoki; Kirby, Michael H; Knoepfel, Kyle James; Kondo, Kunitaka; Kong, Dae Jung; Konigsberg, Jacobo; Kotwal, Ashutosh Vijay; Kreps, Michal; Kroll, IJoseph; Kruse, Mark Charles; Kuhr, Thomas; Kurata, Masakazu; Laasanen, Alvin Toivo; Lammel, Stephan; Lancaster, Mark; Lannon, Kevin Patrick; Latino, Giuseppe; Lee, Hyun Su; Lee, Jaison; Leo, Sabato; Leone, Sandra; Lewis, Jonathan D; Limosani, Antonio; Lipeles, Elliot David; Lister, Alison; Liu, Hao; Liu, Qiuguang; Liu, Tiehui Ted; Lockwitz, Sarah E; Loginov, Andrey Borisovich; Lucchesi, Donatella; Lucà, Alessandra; Lueck, Jan; Lujan, Paul Joseph; Lukens, Patrick Thomas; Lungu, Gheorghe; Lys, Jeremy E; Lysak, Roman; Madrak, Robyn Leigh; Maestro, Paolo; Malik, Sarah Alam; Manca, Giulia; Manousakis-Katsikakis, Arkadios; Marchese, Luigi; Margaroli, Fabrizio; Marino, Christopher Phillip; Matera, Keith; Mattson, Mark Edward; Mazzacane, Anna; Mazzanti, Paolo; McNulty, Ronan; Mehta, Andrew; Mehtala, Petteri; Mesropian, Christina; Miao, Ting; Mietlicki, David John; Mitra, Ankush; Miyake, Hideki; Moed, Shulamit; Moggi, Niccolo; Moon, Chang-Seong; Moore, Ronald Scott; Morello, Michael Joseph; Mukherjee, Aseet; Muller, Thomas; Murat, Pavel A; Mussini, Manuel; Nachtman, Jane Marie; Nagai, Yoshikazu; Naganoma, Junji; Nakano, Itsuo; Napier, Austin; Nett, Jason Michael; Neu, Christopher Carl; Nigmanov, Turgun S; Nodulman, Lawrence J; Noh, Seoyoung; Norniella Francisco, Olga; Oakes, Louise Beth; Oh, Seog Hwan; Oh, Young-do; Oksuzian, Iuri Artur; Okusawa, Toru; Orava, Risto Olavi; Ortolan, Lorenzo; Pagliarone, Carmine Elvezio; Palencia, Jose Enrique; Palni, Prabhakar; Papadimitriou, Vaia; Parker, William Chesluk; Pauletta, Giovanni; Paulini, Manfred; Paus, Christoph Maria Ernst; Phillips, Thomas J; Piacentino, Giovanni M; Pianori, Elisabetta; Pilot, Justin Robert; Pitts, Kevin T; Plager, Charles; Pondrom, Lee G; Poprocki, Stephen; Potamianos, Karolos Jozef; Pranko, Aliaksandr Pavlovich; Prokoshin, Fedor; Ptohos, Fotios K; Punzi, Giovanni; Redondo Fernández, Ignacio; Renton, Peter B; Rescigno, Marco; Rimondi, Franco; Ristori, Luciano; Robson, Aidan; Rodriguez, Tatiana Isabel; Rolli, Simona; Ronzani, Manfredi; Roser, Robert Martin; Rosner, Jonathan L; Ruffini, Fabrizio; Ruiz Jimeno, Alberto; Russ, James S; Rusu, Vadim Liviu; Sakumoto, Willis Kazuo; Sakurai, Yuki; Santi, Lorenzo; Sato, Koji; Saveliev, Valeri; Savoy-Navarro, Aurore; Schlabach, Philip; Schmidt, Eugene E; Schwarz, Thomas A; Scodellaro, Luca; Scuri, Fabrizio; Seidel, Sally C; Seiya, Yoshihiro; Semenov, Alexei; Sforza, Federico; Shalhout, Shalhout Zaki; Shears, Tara G; Shepard, Paul F; Shimojima, Makoto; Shochet, Melvyn J; Shreyber-Tecker, Irina; Simonenko, Alexander V; Sliwa, Krzysztof Jan; Smith, John Rodgers; Snider, Frederick Douglas; Song, Hao; Sorin, Maria Veronica; St Denis, Richard Dante; Stancari, Michelle Dawn; Stentz, Dale James; Strologas, John; Sudo, Yuji; Sukhanov, Alexander I; Suslov, Igor M; Takemasa, Ken-ichi; Takeuchi, Yuji; Tang, Jian; Tecchio, Monica; Teng, Ping-Kun; Thom, Julia; Thomson, Evelyn Jean; Thukral, Vaikunth; Toback, David A; Tokar, Stanislav; Tollefson, Kirsten Anne; Tomura, Tomonobu; Tonelli, Diego; Torre, Stefano; Torretta, Donatella; Totaro, Pierluigi; Trovato, Marco; Ukegawa, Fumihiko; Uozumi, Satoru; Velev, Gueorgui; Vellidis, Konstantinos; Vernieri, Caterina; Vidal Marono, Miguel; Vilar Cortabitarte, Rocio; Vizán Garcia, Jesus Manuel; Vogel, Marcelo; Volpi, Guido; Vázquez-Valencia, Elsa Fabiola; Wagner, Peter; Wallny, Rainer S; Wang, Song-Ming; Waters, David S; Wester, William Carl; Whiteson, Daniel O; Wicklund, Arthur Barry; Wilbur, Scott; Williams, Hugh H; Wilson, Jonathan Samuel; Wilson, Peter James; Winer, Brian L; Wittich, Peter; Wolbers, Stephen A; Wolfe, Homer; Wright, Thomas Roland; Wu, Xin; Wu, Zhenbin; Yamamoto, Kazuhiro; Yamato, Daisuke; Yang, Tingjun; Yang, Un-Ki; Yang, Yu Chul; Yao, Wei-Ming; Yeh, Gong Ping; Yi, Kai; Yoh, John; Yorita, Kohei; Yoshida, Takuo; Yu, Geum Bong; Yu, Intae; Zanetti, Anna Maria; Zeng, Yu; Zhou, Chen; Zucchelli, Stefano

    2015-08-03

    We report on a search for charged massive resonances decaying to top ($t$) and bottom ($b$) quarks in the full data set of proton-antiproton collisions at center-of-mass energy of $\\sqrt{s} = 1.96$ TeV collected by the CDF~II detector at the Tevatron, corresponding to an integrated luminosity of 9.5 $fb^{-1}$. No significant excess above the standard model (SM) background prediction is observed. We set 95% Bayesian credibility mass-dependent upper limits on the heavy charged particle production cross section times branching ratio to $t b$. Using a SM extension with a $W^{\\prime}$ and left-right-symmetric couplings as a benchmark model, we constrain the $W^{\\prime}$ mass and couplings in the 300 to 900 GeV/$c^2$ range. The limits presented here are the most stringent for a charged resonance with mass in the range 300 -- 600 GeV/$c^2$ decaying to top and bottom quarks.

  9. [The search for a precise method of measurement in psychical experiments].

    Science.gov (United States)

    Borck, Cornelius

    2002-06-01

    In a series of three brief case studies, it is reconstructed how cognition and psychic activity were explored as energetic and economic transformations in a variety of experimental settings. 1. In the 1870s, the German psychiatrist Emil Kraepelin started his search for an objective measurement of cognitive performance in which he engaged over several decades. His investigations resulted in a graphic representation of cognitive efficiency, the "arbeitscurve", delineating the numbers of additions per time interval in close resemblance to representations of machine efficiency. 2. At the turn of the century, the American nutrition scientist and agronomist Wilbur Olin Atwater convinced himself in a series of precision measurements that the human motor was a so perfectly closed input-output system that he rejected any mental surplus in the form of cognitive energy transformations as contradictions to the principle of the conservation of energy. 3. At the beginning of the twentieth century and on the basis of Atwater's results, the German psychiatrist Hans Berger stipulated a special form of psychic energy for mediating between the principle of the conservation of energy and mental causality. Berger attempted to quantify psychic energy as one factor of brain metabolism. In the three cases of precision investigations into psychic life presented here, the experimental space of psychophysiology turned mental activity into a form of machine-like behavior.

  10. HST/ACS Imaging of Omega Centauri: Optical Counterparts of Chandra X-Ray Sources

    CERN Document Server

    Cool, Adrienne M; Arias, Tersi; Brochmann, Michelle; Dorfman, Jason; Gafford, April; White, Vivian; Anderson, Jay

    2012-01-01

    We present results of a search for optical counterparts of X-ray sources in and toward the globular cluster Omega Centauri (NGC 5139) using the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. The ACS data consist of a mosaic of Wide Field Channel (WFC) images obtained using F625W, F435W, and F658N filters; with 9 pointings we cover the central ~10'x10' of the cluster and encompass 109 known Chandra sources. We find promising optical counterparts for 59 of the sources, ~40 of which are likely to be associated with the cluster. These include 27 candidate cataclysmic variables (CVs), 24 of which are reported here for the first time. Fourteen of the CV candidates are very faint, with absolute magnitudes in the range M_625 = 10.4 - 12.6, making them comparable in brightness to field CVs near the period minimum discovered in the SDSS (Gansicke et al. 2009). Additional optical counterparts include three BY Dra candidates, a possible blue straggler, and a previously-reported quiescent low-mass X-ray ...

  11. Experimenting with ecosystem interaction networks in search of threshold potentials in real-world marine ecosystems.

    Science.gov (United States)

    Thrush, Simon F; Hewitt, Judi E; Parkes, Samantha; Lohrer, Andrew M; Pilditch, Conrad; Woodin, Sarah A; Wethey, David S; Chiantore, Mariachiara; Asnaghi, Valentina; De Juan, Silvia; Kraan, Casper; Rodil, Ivan; Savage, Candida; Van Colen, Carl

    2014-06-01

    Thresholds profoundly affect our understanding and management of ecosystem dynamics, but we have yet to develop practical techniques to assess the risk that thresholds will be crossed. Combining ecological knowledge of critical system interdependencies with a large-scale experiment, we tested for breaks in the ecosystem interaction network to identify threshold potential in real-world ecosystem dynamics. Our experiment with the bivalves Macomona liliana and Austrovenus stutchburyi on marine sandflats in New Zealand demonstrated that reductions in incident sunlight changed the interaction network between sediment biogeochemical fluxes, productivity, and macrofauna. By demonstrating loss of positive feedbacks and changes in the architecture of the network, we provide mechanistic evidence that stressors lead to break points in dynamics, which theory predicts predispose a system to a critical transition.

  12. Latest results of the direct dark matter search with the EDELWEISS-2 experiment

    CERN Document Server

    ,

    2010-01-01

    EDELWEISS-2 is a Ge-bolometer experiment located in the underground laboratory Laboratoire Souterrain de Modane (LSM, France). For the second phase of the experiment, the collaboration has developed new cryogenic detectors with an improved background rejection (interleaved electrodes design, Phys. Lett. B681 (2009) 305). A continuous operation of ten of these bolometers at LSM together with an active muon veto shielding has been achieved. First results based on an effective exposure of 144 kg \\dot d taken in 2009 have been published recently (Phys. Lett. B687 (2010) 29), the acquired data set has since then been doubled. The already published data correspond to an improvement in sensitivity of about 15 compared to EDELWEISS-1. We present and discuss the latest bolometer data including the identification of muon-induced background events and special measurements of muon-induced neutrons in LSM.

  13. Test experiment to search for a neutron EDM by the Laue diffraction method

    CERN Document Server

    Fedorov, V V; Lelievre-Berna, E; Nesvizhevsky, V V; Petoukhov, A; Semenikhin, S Y; Soldner, T; Tasset, F; Voronin, V V

    2005-01-01

    A prototype experiment to measure the neutron electric dipole moment (nEDM) by spin-rotation in a non-centrosymmetric crystal in Laue geometry was carried out in order to investigate the statistical sensitivity and systematic effects of the method. The statistical sensitivity to the nEDM was about $6\\cdot 10^{-24}$ e$\\cdot $cm per day and can be improved by one order of magnitude for the full scale setup. Systematics was limited by the homogeneity of the magnetic field in the crystal region and by a new kind of spin rotation effect. We attribute this effect to a difference of the two Bloch waves amplitudes in the crystal, which is caused by the presence of a small crystal deformation due to a temperature gradient. In a revised scheme of the experiment, this effect could be exploited for a purposeful manipulation of the Bloch waves.

  14. Search for non Standard Model physics in nuclear-$\\beta$ decay with the WITCH experiment

    CERN Document Server

    Coeck, Sam

    In this work the WITCH experiment, which primarily aims for precision measurements of the beta-neutrino-angular correlation coefficient, is presented in detail. First a theoretical description of the beta-decay process is presented and it was shown how measurements of correlation coefficients can reveal the exact nature of the weak interaction. Although many experiments have already been conducted in this field, there is still considerable room for additional phenomena that are not included in the Standard Model. At WITCH the beta-neutrino-angular correlation coefficient will be obtained from precision measurements of the energy spectrum of the nuclei that recoil after beta-decay, thus avoiding the need to observe the neutrino. To enable a measurement of the recoiling ions, the setup uses a combination of two electromagnetic Penning traps and a retardation spectrometer. This allows one to construct the scattering free radioactive source that is needed as the recoiling ions have only a very small kinetic energ...

  15. Search for electroweak single top-quark production with the CDF II experiment

    Energy Technology Data Exchange (ETDEWEB)

    Richter, Svenja [Karlsruhe Inst. of Technology (Germany)

    2007-11-02

    Understanding the world -- This aim drives humankind since the beginning of conscious thinking. Especially the nature of matter has been of major interest. Nowadays, we have a complex image of the constitution of matter. Atoms consist of electrons and nucleons. But even nucleons are not elementary. Their basic constituents are called quarks. Physicists developed a model describing the elementary components of matter as well as the forces between them: the standard model of elementary particle physics. The substructure of matter is only visible in scattering experiments. In high energy physics, these experiments are done at particle accelerators. The world's highest energetic collider, the Tevatron, is hosted by the Fermi National Accelerator Laboratory (FNAL), also called Fermilab, in the vicinity of Chicago. The proton-antiproton collisions with a center-of-mass energy of {radical}s = 1.96 TeV are recorded by two multipurpose detectors, namely D0 and CDF II.

  16. Search for new particles decaying to a top quark pair with the CMS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Steggemann, Jan

    2012-11-05

    In 2011, the Compact Muon Solenoid (CMS) detector recorded 5 fb{sup -1} of pp collision data delivered by the Large Hadron Collider at a centre-of-mass energy of 7 TeV. The large number of events from t anti t production allows to precisely analyse the production and decay of t anti t pairs in an unprecedented energy regime. In this thesis, the invariant mass distribution of the reconstructed t anti t system (m{sub t} {sub anti} {sub t}) is measured and compared to predictions according to the Standard Model of particle physics. With the help of the measured m{sub t} {sub anti} {sub t} distribution, searches for new particles decaying to a t anti t pair are performed. Such new particles would appear as resonant contributions in addition to the non-resonant m{sub t} {sub anti} {sub t} distributions from Standard Model background processes. The focus of the data analysis extends from invariant top quark pair masses near the production threshold of m{sub t} {sub anti} {sub t}{proportional_to}2 m(top) to the region of m(t anti t){proportional_to}2 TeV. The analysis is based on the final state of the t anti t system with one charged lepton, i.e. either a muon or an electron, a neutrino, and four jets, of which two are b quark jets. A full kinematic reconstruction of these events is performed with a {chi}{sup 2} method. The selected events are divided in 8 subsamples according to the number of selected jets, the number of jets that are identified as b quark jets, and the lepton flavour (muon or electron). This categorisation takes advantage of the different signal-to-background ratios in the different event categories and improves the statistical sensitivity of the search. The measured m{sub t} {sub anti} {sub t} distributions in all 8 subsamples show good agreement with the expectation from the background processes that are simulated according to the Standard Model. The compatibility is tested by performing a background-only fit including all relevant systematic

  17. Search for narrow. mu. (. pi. ( mass enhancements in a neutrino bubble-chamber experiment

    Energy Technology Data Exchange (ETDEWEB)

    Ballagh, H.C.; Bingham, H.H.; Lawry, T.J.; Lynch, G.R.; Lys, J.; Stevenson, M.L.; Huson, F.R.; Schmidt, E.; Smart, W.; Sokoloff, M.D.

    1984-04-01

    In a Fermilab 15-foot bubble-chamber experiment, ..mu../sup - +/..pi../sup + -/ mass spectra were studied in 8444 neutrino interactions and 1367 antineutrino interactions. No significant narrow mass enhancements were found. A peak near 430 MeV/c/sup 2/ was observed, but when resolution is taken into account its significance is only roughly-equal1sigma and its angular distributions do not show the characteristics expected for a resonance.

  18. In Search of an Effective C2 Architecture for Counterinsurgency Operations: Lessons from the Colombian Experience

    Science.gov (United States)

    2006-06-01

    Lessons from the Colombian Experience Lessons Learned, Concepts and Organizations, Social Domain Issues Román D. Ortiz, Nicolás Urrutia...Nicolás Urrutia Universidad de los Andes Departamento de Ciencia Política Carrera 1E # 18A - 10 Edificio Franco, Piso 3 Telephone: (57-1) 339...and military, and analyzes their impact upon the design of system architecture over time. In addition, it offers insight into the social processes

  19. A search for R-parity violating squark production with the H1 experiment at HERA

    Energy Technology Data Exchange (ETDEWEB)

    Herbst, Michael Clemens

    2011-12-15

    A search for R-parity violating supersymmetry is performed in the complete HERA data set taken at a centre-of-mass energy of {radical}(s)=319 GeV with the H1 detector. The integrated luminosity of the data sets corresponds to 255 pb{sup -1} of positron-proton, and 183 pb{sup -1} of electron-proton collision data. By introducing a lepton-quark-squark coupling {lambda}{sup '} the resonant production of single squarks is expected. Several exclusive selection channels, based on the topologies of final states expected from direct squark decays, and squark decays via gauginos are defined. The selection channels are based on an electron or a neutrino in the final state, and may contain further jets and leptons. All of the selection channels show a good agreement with the background expectation from standard model processes. The results are interpreted in terms of exclusion limits, obtained for the minimal supersymmetric standard model, and for the minimal supergravity model, constraining the strength of the R-parity violating couplings {lambda}{sub 1j1}{sup '} and {lambda}{sub 11k}{sup '}, and the supersymmetric model parameters, under the single coupling dominance hypothesis. For an R{sub p} coupling strength comparable to the electromagnetic coupling strength, {lambda}{sub 1j1}{sup '} or {lambda}{sub 11k}{sup '}={radical}(4{pi}{alpha}{sub em})=0.3, squark masses up to 275 GeV are excluded for u{sup j}{sub L} squarks, with d{sup k}{sub R} squarks further excluded up to 290 GeV, for all three squark generations j,k=1,2,3 at the 95% confidence level. (orig.)

  20. Simulated forecasts for primordial B-mode searches in ground-based experiments

    CERN Document Server

    Alonso, David; Naess, Sigurd; Thorne, Ben

    2016-01-01

    Detecting the imprint of inflationary gravitational waves on the $B$-mode polarization of the Cosmic Microwave Background (CMB) is one of the main science cases for current and next-generation CMB experiments. In this work we explore some of the challenges that ground-based facilities will have to face in order to carry out this measurement in the presence of Galactic foregrounds and correlated atmospheric noise. We present forecasts for Stage-3 (S3) and planned Stage-4 (S4) experiments based on the analysis of simulated sky maps using a map-based Bayesian foreground cleaning method. Our results thus consistently propagate the uncertainties on foreground parameters such as spatially-varying spectral indices, as well as the bias on the measured tensor-to-scalar ratio $r$ caused by an incorrect modelling of the foregrounds. We find that S3 and S4-like experiments should be able to put constraints on $r$ of the order $\\sigma(r)=(0.5-1.0)\\times10^{-2}$ and $\\sigma(r)=(0.5-1.0)\\times10^{-3}$ respectively, assuming...

  1. Search for scalar leptoquarks in pp collisions at \\sqrt{s} = 13 TeV with the ATLAS experiment

    Science.gov (United States)

    The ATLAS Collaboration; Aaboud, M.; Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Abeloos, B.; Aben, R.; AbouZeid, O. S.; Abraham, N. L.; Abramowicz, H.; Abreu, H.; Abreu, R.; Abulaiti, Y.; Acharya, B. S.; Adamczyk, L.; Adams, D. L.; Adelman, J.; Adomeit, S.; Adye, T.; Affolder, A. A.; Agatonovic-Jovin, T.; Agricola, J.; Aguilar-Saavedra, J. A.; Ahlen, S. P.; Ahmadov, F.; Aielli, G.; Akerstedt, H.; Åkesson, T. P. A.; Akimov, A. V.; Alberghi, G. L.; Albert, J.; Albrand, S.; Alconada Verzini, M. J.; Aleksa, M.; Aleksandrov, I. N.; Alexa, C.; Alexander, G.; Alexopoulos, T.; Alhroob, M.; Aliev, M.; Alimonti, G.; Alison, J.; Alkire, S. P.; Allbrooke, B. M. M.; Allen, B. W.; Allport, P. P.; Aloisio, A.; Alonso, A.; Alonso, F.; Alpigiani, C.; Alstaty, M.; Alvarez Gonzalez, B.; Álvarez Piqueras, D.; Alviggi, M. G.; Amadio, B. T.; Amako, K.; Amaral Coutinho, Y.; Amelung, C.; Amidei, D.; Amor Dos Santos, S. P.; Amorim, A.; Amoroso, S.; Amundsen, G.; Anastopoulos, C.; Ancu, L. S.; Andari, N.; Andeen, T.; Anders, C. F.; Anders, G.; Anders, J. K.; Anderson, K. J.; Andreazza, A.; Andrei, V.; Angelidakis, S.; Angelozzi, I.; Anger, P.; Angerami, A.; Anghinolfi, F.; Anisenkov, A. V.; Anjos, N.; Annovi, A.; Antonelli, M.; Antonov, A.; Anulli, F.; Aoki, M.; Aperio Bella, L.; Arabidze, G.; Arai, Y.; Araque, J. P.; Arce, A. T. H.; Arduh, F. A.; Arguin, J.-F.; Argyropoulos, S.; Arik, M.; Armbruster, A. J.; Armitage, L. J.; Arnaez, O.; Arnold, H.; Arratia, M.; Arslan, O.; Artamonov, A.; Artoni, G.; Artz, S.; Asai, S.; Asbah, N.; Ashkenazi, A.; Åsman, B.; Asquith, L.; Assamagan, K.; Astalos, R.; Atkinson, M.; Atlay, N. B.; Augsten, K.; Avolio, G.; Axen, B.; Ayoub, M. K.; Azuelos, G.; Baak, M. A.; Baas, A. E.; Baca, M. J.; Bachacou, H.; Bachas, K.; Backes, M.; Backhaus, M.; Bagiacchi, P.; Bagnaia, P.; Bai, Y.; Baines, J. T.; Baker, O. K.; Baldin, E. M.; Balek, P.; Balestri, T.; Balli, F.; Balunas, W. K.; Banas, E.; Banerjee, Sw; Bannoura, A. A. E.; Barak, L.; Barberio, E. L.; Barberis, D.; Barbero, M.; Barillari, T.; Barklow, T.; Barlow, N.; Barnes, S. L.; Barnett, B. M.; Barnett, R. M.; Barnovska, Z.; Baroncelli, A.; Barone, G.; Barr, A. J.; Barranco Navarro, L.; Barreiro, F.; Barreiro Guimarães da Costa, J.; Bartoldus, R.; Barton, A. E.; Bartos, P.; Basalaev, A.; Bassalat, A.; Bates, R. L.; Batista, S. J.; Batley, J. R.; Battaglia, M.; Bauce, M.; Bauer, F.; Bawa, H. S.; Beacham, J. B.; Beattie, M. D.; Beau, T.; Beauchemin, P. H.; Bechtle, P.; Beck, H. P.; Becker, K.; Becker, M.; Beckingham, M.; Becot, C.; Beddall, A. J.; Beddall, A.; Bednyakov, V. A.; Bedognetti, M.; Bee, C. P.; Beemster, L. J.; Beermann, T. A.; Begel, M.; Behr, J. K.; Belanger-Champagne, C.; Bell, A. S.; Bella, G.; Bellagamba, L.; Bellerive, A.; Bellomo, M.; Belotskiy, K.; Beltramello, O.; Belyaev, N. L.; Benary, O.; Benchekroun, D.; Bender, M.; Bendtz, K.; Benekos, N.; Benhammou, Y.; Benhar Noccioli, E.; Benitez, J.; Benjamin, D. P.; Bensinger, J. R.; Bentvelsen, S.; Beresford, L.; Beretta, M.; Berge, D.; Bergeaas Kuutmann, E.; Berger, N.; Beringer, J.; Berlendis, S.; Bernard, N. R.; Bernius, C.; Bernlochner, F. U.; Berry, T.; Berta, P.; Bertella, C.; Bertoli, G.; Bertolucci, F.; Bertram, I. A.; Bertsche, C.; Bertsche, D.; Besjes, G. J.; Bessidskaia Bylund, O.; Bessner, M.; Besson, N.; Betancourt, C.; Bethke, S.; Bevan, A. J.; Bhimji, W.; Bianchi, R. M.; Bianchini, L.; Bianco, M.; Biebel, O.; Biedermann, D.; Bielski, R.; Biesuz, N. V.; Biglietti, M.; Bilbao De Mendizabal, J.; Bilokon, H.; Bindi, M.; Binet, S.; Bingul, A.; Bini, C.; Biondi, S.; Bjergaard, D. M.; Black, C. W.; Black, J. E.; Black, K. M.; Blackburn, D.; Blair, R. E.; Blanchard, J.-B.; Blanco, J. E.; Blazek, T.; Bloch, I.; Blocker, C.; Blum, W.; Blumenschein, U.; Blunier, S.; Bobbink, G. J.; Bobrovnikov, V. S.; Bocchetta, S. S.; Bocci, A.; Bock, C.; Boehler, M.; Boerner, D.; Bogaerts, J. A.; Bogavac, D.; Bogdanchikov, A. G.; Bohm, C.; Boisvert, V.; Bokan, P.; Bold, T.; Boldyrev, A. S.; Bomben, M.; Bona, M.; Boonekamp, M.; Borisov, A.; Borissov, G.; Bortfeldt, J.; Bortoletto, D.; Bortolotto, V.; Bos, K.; Boscherini, D.; Bosman, M.; Bossio Sola, J. D.; Boudreau, J.; Bouffard, J.; Bouhova-Thacker, E. V.; Boumediene, D.; Bourdarios, C.; Boutle, S. K.; Boveia, A.; Boyd, J.; Boyko, I. R.; Bracinik, J.; Brandt, A.; Brandt, G.; Brandt, O.; Bratzler, U.; Brau, B.; Brau, J. E.; Braun, H. M.; Breaden Madden, W. D.; Brendlinger, K.; Brennan, A. J.; Brenner, L.; Brenner, R.; Bressler, S.; Bristow, T. M.; Britton, D.; Britzger, D.; Brochu, F. M.; Brock, I.; Brock, R.; Brooijmans, G.; Brooks, T.; Brooks, W. K.; Brosamer, J.; Brost, E.; Broughton, J. H.; Bruckman de Renstrom, P. A.; Bruncko, D.; Bruneliere, R.; Bruni, A.; Bruni, G.; Bruni, L. S.; Brunt, B. H.

    2016-09-01

    An inclusive search for a new-physics signature of lepton-jet resonances has been performed by the ATLAS experiment. Scalar leptoquarks, pair-produced in pp collisions at \\sqrt{s} = 13 TeV at the large hadron collider, have been considered. An integrated luminosity of 3.2 fb-1, corresponding to the full 2015 dataset was used. First (second) generation leptoquarks were sought in events with two electrons (muons) and two or more jets. The observed event yield in each channel is consistent with Standard Model background expectations. The observed (expected) lower limits on the leptoquark mass at 95% confidence level are 1100 and 1050 GeV (1160 and 1040 GeV) for first and second generation leptoquarks, respectively, assuming a branching ratio into a charged lepton and a quark of 100%. Upper limits on the aforementioned branching ratio are also given as a function of leptoquark mass. Compared with the results of earlier ATLAS searches, the sensitivity is increased for leptoquark masses above 860 GeV, and the observed exclusion limits confirm and extend the published results.

  2. A model independent search for new physics in final states containing leptons at the D0 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Piper, Joel Michael [Michigan State Univ., East Lansing, MI (United States)

    2009-01-01

    The standard model is known to be the low energy limit of a more general theory. Several consequences of the standard model point to a strong probability of new physics becoming experimentally visible in high energy collisions of a few TeV, resulting in high momentum objects. The specific signatures of these collisions are topics of much debate. Rather than choosing a specific signature, this analysis broadly searches the data, preferring breadth over sensitivity. In searching for new physics, several different approaches are used. These include the comparison of data with standard model background expectation in overall number of events, comparisons of distributions of many kinematic variables, and finally comparisons on the tails of distributions that sum the momenta of the objects in an event. With 1.07 fb-1 at the D0 experiment, we find no evidence of physics beyond the standard model. Several discrepancies from the standard model were found, but none of these provide a compelling case for new physics.

  3. D-D Neutron Generator Calibrations and Hardware in the LUX-ZEPLIN Dark Matter Search Experiment

    Science.gov (United States)

    Taylor, Will; Lux-Zeplin Collaboration

    2016-03-01

    The LUX-ZEPLIN (LZ) dark matter search experiment will be a two-phase liquid/gas xenon time projection chamber with 7 tonnes of active liquid xenon (LXe) located at the 4850 ft level of the Sanford Underground Research Facility in Lead, SD. LZ will utilize an in-situ, absolute calibration of nuclear recoils (NR) in LXe using mono-energetic 2.45 MeV neutrons produced by a D-D neutron generator. This technique was used in the LUX detector to measured the NR charge yield in LXe (Qy) to 0.7 keV recoil energy and the NR light yield in LXe (Ly) to recoil energies of 1.1 keV - both of which were the lowest energy measurements achieved in the field. These absolute, ultra-low energy calibrations of the NR signal yields in LXe provide clear measurements of the detector response used for the WIMP search analysis. The improvements made for LZ will include shorter neutron pulse times, multiple neutron conduit configurations, and lower energy neutrons. The upgrades allow for even lower energy measurements of the nuclear recoil response in LXe and an independent measurement of Ly, as well as providing less uncertainty in energy reconstruction. In addition to discussing the physics of the neutron calibrations, I will describe the hardware systems used to implement them.

  4. Search for scalar leptoquarks in $pp$ collisions at $\\sqrt{s} = 13$ TeV with the ATLAS experiment

    CERN Document Server

    Aaboud, Morad; Abbott, Brad; Abdallah, Jalal; Abdinov, Ovsat; Abeloos, Baptiste; Aben, Rosemarie; AbouZeid, Ossama; Abraham, Nicola; Abramowicz, Halina; Abreu, Henso; Abreu, Ricardo; Abulaiti, Yiming; Acharya, Bobby Samir; Adamczyk, Leszek; Adams, David; Adelman, Jahred; Adomeit, Stefanie; Adye, Tim; Affolder, Tony; Agatonovic-Jovin, Tatjana; Agricola, Johannes; Aguilar-Saavedra, Juan Antonio; Ahlen, Steven; Ahmadov, Faig; Aielli, Giulio; Akerstedt, Henrik; Åkesson, Torsten Paul Ake; Akimov, Andrei; Alberghi, Gian Luigi; Albert, Justin; Albrand, Solveig; Alconada Verzini, Maria Josefina; Aleksa, Martin; Aleksandrov, Igor; Alexa, Calin; Alexander, Gideon; Alexopoulos, Theodoros; Alhroob, Muhammad; Aliev, Malik; Alimonti, Gianluca; Alison, John; Alkire, Steven Patrick; Allbrooke, Benedict; Allen, Benjamin William; Allport, Phillip; Aloisio, Alberto; Alonso, Alejandro; Alonso, Francisco; Alpigiani, Cristiano; Alstaty, Mahmoud; Alvarez Gonzalez, Barbara; Άlvarez Piqueras, Damián; Alviggi, Mariagrazia; Amadio, Brian Thomas; Amako, Katsuya; Amaral Coutinho, Yara; Amelung, Christoph; Amidei, Dante; Amor Dos Santos, Susana Patricia; Amorim, Antonio; Amoroso, Simone; Amundsen, Glenn; Anastopoulos, Christos; Ancu, Lucian Stefan; Andari, Nansi; Andeen, Timothy; Anders, Christoph Falk; Anders, Gabriel; Anders, John Kenneth; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Angelidakis, Stylianos; Angelozzi, Ivan; Anger, Philipp; Angerami, Aaron; Anghinolfi, Francis; Anisenkov, Alexey; Anjos, Nuno; Annovi, Alberto; Antonelli, Mario; Antonov, Alexey; Anulli, Fabio; Aoki, Masato; Aperio Bella, Ludovica; Arabidze, Giorgi; Arai, Yasuo; Araque, Juan Pedro; Arce, Ayana; Arduh, Francisco Anuar; Arguin, Jean-Francois; Argyropoulos, Spyridon; Arik, Metin; Armbruster, Aaron James; Armitage, Lewis James; Arnaez, Olivier; Arnold, Hannah; Arratia, Miguel; Arslan, Ozan; Artamonov, Andrei; Artoni, Giacomo; Artz, Sebastian; Asai, Shoji; Asbah, Nedaa; Ashkenazi, Adi; Åsman, Barbro; Asquith, Lily; Assamagan, Ketevi; Astalos, Robert; Atkinson, Markus; Atlay, Naim Bora; Augsten, Kamil; Avolio, Giuseppe; Axen, Bradley; Ayoub, Mohamad Kassem; Azuelos, Georges; Baak, Max; Baas, Alessandra; Baca, Matthew John; Bachacou, Henri; Bachas, Konstantinos; Backes, Moritz; Backhaus, Malte; Bagiacchi, Paolo; Bagnaia, Paolo; Bai, Yu; Baines, John; Baker, Oliver Keith; Baldin, Evgenii; Balek, Petr; Balestri, Thomas; Balli, Fabrice; Balunas, William Keaton; Banas, Elzbieta; Banerjee, Swagato; Bannoura, Arwa A E; Barak, Liron; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Barillari, Teresa; Barklow, Timothy; Barlow, Nick; Barnes, Sarah Louise; Barnett, Bruce; Barnett, Michael; Barnovska, Zuzana; Baroncelli, Antonio; Barone, Gaetano; Barr, Alan; Barranco Navarro, Laura; Barreiro, Fernando; Barreiro Guimarães da Costa, João; Bartoldus, Rainer; Barton, Adam Edward; Bartos, Pavol; Basalaev, Artem; Bassalat, Ahmed; Bates, Richard; Batista, Santiago Juan; Batley, Richard; Battaglia, Marco; Bauce, Matteo; Bauer, Florian; Bawa, Harinder Singh; Beacham, James; Beattie, Michael David; Beau, Tristan; Beauchemin, Pierre-Hugues; Bechtle, Philip; Beck, Hans~Peter; Becker, Kathrin; Becker, Maurice; Beckingham, Matthew; Becot, Cyril; Beddall, Andrew; Beddall, Ayda; Bednyakov, Vadim; Bedognetti, Matteo; Bee, Christopher; Beemster, Lars; Beermann, Thomas; Begel, Michael; Behr, Janna Katharina; Belanger-Champagne, Camille; Bell, Andrew Stuart; Bella, Gideon; Bellagamba, Lorenzo; Bellerive, Alain; Bellomo, Massimiliano; Belotskiy, Konstantin; Beltramello, Olga; Belyaev, Nikita; Benary, Odette; Benchekroun, Driss; Bender, Michael; Bendtz, Katarina; Benekos, Nektarios; Benhammou, Yan; Benhar Noccioli, Eleonora; Benitez, Jose; Benjamin, Douglas; Bensinger, James; Bentvelsen, Stan; Beresford, Lydia; Beretta, Matteo; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Beringer, Jürg; Berlendis, Simon; Bernard, Nathan Rogers; Bernius, Catrin; Bernlochner, Florian Urs; Berry, Tracey; Berta, Peter; Bertella, Claudia; Bertoli, Gabriele; Bertolucci, Federico; Bertram, Iain Alexander; Bertsche, Carolyn; Bertsche, David; Besjes, Geert-Jan; Bessidskaia Bylund, Olga; Bessner, Martin Florian; Besson, Nathalie; Betancourt, Christopher; Bethke, Siegfried; Bevan, Adrian John; Bhimji, Wahid; Bianchi, Riccardo-Maria; Bianchini, Louis; Bianco, Michele; Biebel, Otmar; Biedermann, Dustin; Bielski, Rafal; Biesuz, Nicolo Vladi; Biglietti, Michela; Bilbao De Mendizabal, Javier; Bilokon, Halina; Bindi, Marcello; Binet, Sebastien; Bingul, Ahmet

    2016-01-01

    An inclusive search for a new-physics signature of lepton-jet resonances has been performed by the ATLAS experiment. Scalar leptoquarks, pair-produced in $pp$ collisions at $\\sqrt{s}$ = 13 TeV at the Large Hadron Collider have been considered. An integrated luminosity of 3.2 fb$^{-1}$, corresponding to the full 2015 dataset was used. First (second) generation leptoquarks were sought in events with two electrons (muons) and two or more jets. The observed yield in each channel is consistent with Standard Model background expectations. The observed (expected) leptoquark mass limits at 95% confidence level are 1100 GeV and 1050 GeV (1160 GeV and 1040 GeV) for first and second generation leptoquarks, respectively, assuming a branching ratio into a charged lepton and a quark of 100%. Upper limits on the aforementioned branching ratio are also given as a function of leptoquark mass. Compared with the results of earlier ATLAS searches, the sensitivity is increased for the higher range of accessible leptoquark masses,...

  5. Search for vector-like T' quarks using tools for the analysis of jet substructure with the CMS experiment

    CERN Document Server

    Höing, Rebekka Sophie; Haller, Johannes

    2015-01-01

    A search for pairs of vector-like T' quark produced in proton-proton collisions recorded with the CMS experiment at p s = 8 TeV is presented. The search is optimized for decays of T' quarks to top quarks and Higgs bosons, where the top quarks and Higgs bosons decay hadronically. The T'-quark mass range between 500 and 1000 GeV is investigated. The top quarks and Higgs bosons produced in decays of the heavy T' quarks acquire large Lorentz boosts. The signatures of these particles in the detector can overlap and are therefore dicult to resolve using classical jet reconstruction methods. Large-radius jets are reconstructed and subjets formed from their constituents. The decay products of particles with large Lorentz boosts are highly collimated and can all be found within a single one of these large-radius jets. Top jets containing hadronic top-quark decays are identied with a top-tagging algorithm that analyzes the jet substructure. A b-tagging algorithm is applied to the reconstructed subjets in order to nd bo...

  6. Core-collapse supernovae as possible counterparts of IceCube neutrino multiplets

    Energy Technology Data Exchange (ETDEWEB)

    Strotjohann, Nora Linn; Kowalski, Marek; Franckowiak, Anna [DESY, Zeuthen (Germany); Voge, Markus [Bonn Univ. (Germany). Physikalisches Institut; Collaboration: IceCube-Collaboration

    2016-07-01

    While an astrophysical neutrino flux has been detected by the IceCube Neutrino Observatory its sources remain so far unidentified. IceCube's Optical Follow-up Program is designed to search for the counterparts of neutrino multiplets using the full energy range of the IceCube detector down to 100 GeV. Two or more muon neutrinos arriving from the same direction within few seconds can trigger follow-up observations with optical and X-ray telescopes. Since 2010 the Palomar Transient Factory has followed up about 40 such neutrino alerts and detected several supernovae. Many of the detections are however likely random coincidences. In this talk I describe our search for supernovae and the prospects of identifying a supernova as a source of high-energy neutrinos.

  7. Questioning the Search for Illness Narratives in Medical Anthropology: Can we talk about actual pain experiences?

    DEFF Research Database (Denmark)

    Tørring, Marie Louise

    of the anthropological literature on pain from the 1950's up to today. RESULTS: The anthropological focus on pain has changed considerably during the last century from exotic tales of cultural codes of pain behaviour to illness narratives of pain experience. This shift in focus not only mirrors changes in our profession......, phenomenological way of understanding pain. CONCLUSION: My empirical findings show that a narrative approach only offer a partial understanding of how we acquire knowledge of other people's pain - this goes for health professionals as well as ethnographers. A more contextual approach - studying pain behaviour...

  8. Results of the Search for Strange Quark Matter and Q-balls with the SLIM Experiment

    CERN Document Server

    Cecchini, S; Di Ferdinando, D; Errico, M; Fabbri, F; Giacomelli, G; Giacomelli, R; Giorgini, M; Kumar, A; McDonald, J; Mandrioli, G; Manzoor, S; Margiotta, A; Medinaceli, E; Patrizii, L; Pinfold, J L; Popa, V; Qureshi, I E; Saavedra, O; Sahnoun, Z; Sirri, G; Spurio, M; Togo, V; Valieri, C; Velarde, A; Zanini, A

    2008-01-01

    The SLIM experiment at the Chacaltaya high altitude laboratory was sensitive to nuclearites and Q-balls, which could be present in the cosmic radiation as possible Dark Matter components. It was sensitive also to strangelets, i.e. small lumps of Strange Quark Matter predicted at such altitudes by various phenomenological models. The analysis of 427 m^2 of Nuclear Track Detectors exposed for 4.22 years showed no candidate event. New upper limits on the flux of downgoing nuclearites and Q-balls at the 90% C.L. were established. The null result also restricts models for strangelets propagation through the Earth atmosphere.

  9. Optimizing the θ 23 octant search in long baseline neutrino experiments

    Science.gov (United States)

    Das, C. R.; Maalampi, J.; Pulido, J.; Vihonen, S.

    2017-09-01

    Determination of the θ 23 octant will be an important goal for the next generation of neutrino oscillation experiments, as it will show whether the true value of θ 23 lies in the high octant, θ 23 > 45°, or in the low octant, θ 23 terms of baseline length and beam sharing and use the LBNO setup as our benchmark. We also show the interference on the octant determination that arises from the unconstrained CP violation angle δ CP. In our results, we show the impact of matter effects on the octant determination potential and establish a connection between the beam sharing and mass hierarchy.

  10. Searching for What I Want

    DEFF Research Database (Denmark)

    Liu, Fei; Xiao, Bo Sophia; Lim, Eric

    2016-01-01

    of anticipa-tory system as our theoretical foundation to articulate the relationships between two salient types of search controls, namely search anticipation and search efficiency. We empirically validate our re-search model by conducting a field survey with 77 university students on an online restaurant......Inefficiencies associated with online information search are amplifying in the current era of big data. Despite growing scholarly interest in studying Internet users’ information search behaviour, there is a paucity of theory-guided investigation in this regard. In this paper, we draw on the theory...... review website that is modelled after its actual counterpart and populated with real restaurant review data. Findings from this study suggest that both search determination control and search manipulation con-trol enhance search result anticipation, which in turn improves search efficiency. Theoretical...

  11. The CMS forward calorimeter prototype design studies and Ω$0\\atop{C}$ search at E781 experiment at Fermilab

    Energy Technology Data Exchange (ETDEWEB)

    Ayan, Ahmet Sedat [Univ. of Iowa, Iowa City, IA (United States)

    2004-05-01

    In the fit part, the Compact Muon Solenoid (CMS) forward calorimeter design studies are presented. The forward calorimeter consists of quartz fibers embedded in a steel absorber. Radiation damage studies of the quartz fiber and the absorber as well as the results of the first pre-production prototype PPP-I are presented. In the second part, the Ω$0\\atop{C}$ search studies at the SELEX (E781) experiment at FermiLab are presented. 107 ± 22 Ω$0\\atop{C}$ events are observed in three decay modes. The relative branching ratio (Ω$0\\atop{C}$ → Ω-π-π+π+)/β(Ω$0\\atop{C}$ {yields} Ω-π+) is measured as 2.00 ± 0.45(stat) ± 0.32(sys).

  12. Development of cryogenic CMOS Readout ASICs for the Point-Contact HPGe Detectors for Dark Matter Search and Neutrino Experiments

    Science.gov (United States)

    Deng, Zhi; He, Li; Liu, Feng; Liu, Yinong; Xue, Tao; Li, Yulan; Yue, Qian

    2017-05-01

    The paper presents the developments of two cryogenic readout ASICs for the point-contact HPGe detectors for dark matter search and neutrino experiments. Extremely low noise readout electronics were demanded and the capability of working at cryogenic temperatures may bring great advantages. The first ASIC was a monolithic CMOS charge sensitive preamplifier with its noise optimized for ∼1 pF input capacitance. The second ASIC was a waveform recorder based on switched capacitor array. These two ASICs were fabricated in CMOS 350 nm and 180 nm processes respectively. The prototype chips were tested and showed promising results. Both ASICs worked well at low temperature. The preamplifier had achieved ENC of 10.3 electrons with 0.7 pF input capacitance and the SCA chip could run at 9 bit effective resolution and 25 MSPS sampling rate.

  13. Dark matter search in a Beam-Dump eXperiment (BDX) at Jefferson Lab

    CERN Document Server

    Battaglieri, M; Caiffi, B; Celentano, A; De Vita, R; Fanchini, E; Marsicano, L; Musico, P; Osipenko, M; Panza, F; Ripani, M; Santopinto, E; Taiuti, M; Bellini, V; Bondí, M; De Napoli, M; Mammoliti, F; Leonora, E; Randazzo, N; Russo, G; Sperduto, M; Sutera, C; Tortorici, F; Baltzell, N; Dalton, M; Freyberger, A; Girod, F X; Kubarovsky, V; Pasyuk, E; Smith, E S; Stepanyan, S; Ungaro, M; Whitlatch, T; Izaguirre, E; Krnjaic, G; Snowden-Ifft, D; Loomba, D; Carpinelli, M; Sipala, V; Schuster, P; Toro, N; Essig, R; Wood, M H; Holtrop, M; Paremuzyan, R; De Cataldo, G; De Leo, R; Di Bari, D; Lagamba, L; Nappi, E; Perrino, R; Balossino, I; Barion, L; Ciullo, G; Contalbrigo, M; Lenisa, P; Movsisyan, A; Spizzo, F; Turisini, M; De Persio, F; Cisbani, E; Garibaldi, F; Meddi, F; Urciuoli, G M; Hasch, D; Lucherini, V; Mirazita, M; Pisano, S; Simi, G; D'Angelo, A; Lanza, L; Rizzo, A; Schaerf, C; Zonta, I; Filippi, A; Fegan, S; Kunkel, M; Bashkanov, M; Beltrame, P; Murphy, A; Smith, G; Watts, D; Zachariou, N; Zana, L; Glazier, D; Ireland, D; McKinnon, B; Sokhan, D; Colaneri, L; Pereira, S Anefalos; Afanasev, A; Briscoe, B; Strakovsky, I; Kalantarians, N; Weinstein, L; Adhikari, K P; Dunne, J A; Dutta, D; Fassi, L El; Ye, L; Hicks, K; Cole, P; Dobbs, S; Fanelli, C

    2016-01-01

    MeV-GeV dark matter (DM) is theoretically well motivated but remarkably unexplored. This proposal presents the MeV-GeV DM discovery potential for a $\\sim$1 m$^3$ segmented CsI(Tl) scintillator detector placed downstream of the Hall A beam-dump at Jefferson Lab, receiving up to 10$^{22}$ electrons-on-target (EOT) in 285 days. This experiment (Beam-Dump eXperiment or BDX) would be sensitive to elastic DM-electron and to inelastic DM scattering at the level of 10 counts per year, reaching the limit of the neutrino irreducible background. The distinct signature of a DM interaction will be an electromagnetic shower of few hundreds of MeV, together with a reduced activity in the surrounding active veto counters. A detailed description of the DM particle $\\chi$ production in the dump and subsequent interaction in the detector has been performed by means of Monte Carlo simulations. Different approaches have been used to evaluate the expected backgrounds: the cosmogenic background has been extrapolated from the result...

  14. Trigger for rare kaon decays searches at the CERN NA62 experiment

    CERN Document Server

    Angelucci, Bruno

    The work reported in this thesis has been carried out within the Trigger and Data Ac- quisition (TDAQ) working group of the CERN NA62 experiment, and focused on the development of a trigger strategy for collecting rare kaon decays. The main aim of the NA62 experiment is the study of the ultra rare decay K + ! + in order to provide a stringent test of the Standard Model. The theoretical framework of the K + ! + decay, the present experimental status of the measurement of the Branching Ratio and the NA62 experimental strategy are described in chapter 1. Chapter 2 provides a description of the NA62 experimental setup. The first part of the work concerned the design, development and assessment of the common Trigger and Data Acquisition system for the majority of detectors in NA62, a high-speed integrated data acquisition and trigger generation system based on digital high resolution time measurements. The architecture of the boards, a detailed description of the devel- oped firmwares and some results obta...

  15. Searching for Physics beyond the Standard Model with Accelerator Neutrino Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Louis, William C [Los Alamos National Laboratory

    2008-01-01

    The MiniBooNE experiment at Fermilab was designed to test the LSND evidence for {bar {nu}}{sub {mu}} {yields} {bar {nu}}{sub e} oscillations . The first MiniBooNE oscillation result in neutrino mode shows no significant excess of events at higher energies (E{sub {nu}} > 475 MeV), although a sizeable excess is observed at lower energies (E{sub {nu}}< 475 MeV). The lack of a significant excess at higher energies allows MiniBooNE to rule out simple 2 - {nu} oscillations as an explanation of the LSND signal. However, the low-energy excess is presently unexplained. Additional antineutrino data and NuMI data may allow the collaboration to determine whether the excess is due, for example, to a neutrino neutral-current radiative interaction or to neutrino oscillations involving sterile neutrinos. If the excess is consistent with being due to sterile neutrinos, then future experiments at FNAL (BooNE) or ORNL (OscSNS) could prove their existence.

  16. Cosmologists in Search of Planet Nine: the Case for CMB Experiments

    CERN Document Server

    Cowan, Nicolas B; Kaib, Nathan A

    2016-01-01

    Cosmology experiments at mm-wavelengths may be able to detect Planet Nine if it is the size of Neptune, has an effective temperature of 40 K, and is 700 AU from the Sun. It would appear as a ~30 mJy source at 1 mm (or ~8 mJy at 150 GHz) with a parallax of ~5 arcmin. The challenge will be to distinguish it from the ~4000 foreground asteroids brighter than 30 mJy. Fortunately, asteroids can by identified by looking for sources that move across a resolution element in a matter of hours, orders of magnitude faster than Planet Nine. If Planet Nine is smaller, colder, and/or more distant than expected, then it could be as faint as 1 mJy at 1 mm. There are approximately 1E6 asteroids this bright, making many cosmology experiments confusion limited for moving sources. Nonetheless, it may still be possible to find the proverbial needle in the haystack using a matched filter. This would require mm telescopes with high angular resolution and high sensitivity in order to alleviate confusion and to enable the identificati...

  17. Dark matter search in a Beam-Dump eXperiment (BDX) at Jefferson Lab

    CERN Document Server

    Battaglieri, M; De Vita, R; Izaguirre, E; Krnjaic, G; Smith, E; Stepanyan, S; Bersani, A; Fanchini, E; Fegan, S; Musico, P; Osipenko, M; Ripani, M; Santopinto, E; Taiuti, M; Schuster, P; Toro, N; Dalton, M; Freyberger, A; Girod, F -X; Kubarovsky, V; Ungaro, M; De Cataldo, G; De Leo, R; Di Bari, D; Lagamba, L; Nappi, E; Perrino, R; Carpinelli, M; Sipala, V; Aiello, S; Bellini, V; De Napoli, M; Giusa, A; Mammoliti, F; Leonora, E; Noto, F; Randazzo, N; Russo, G; Sperduto, M; Sutera, C; Ventura, C; Barion, L; Ciullo, G; Contalbrigo, M; Lenisa, P; Movsisyan, A; Spizzo, F; Turisini, M; De Persio, F; Cisbani, E; Fanelli, C; Garibaldi, F; Meddi, F; Urciuoli, G M; Pereira, S Anefalos; De Sanctis, E; Hasch, D; Lucherini, V; Mirazita, M; Montgomery, R; Pisano, S; Simi, G; D'Angelo, A; Lanza, L Colaneri L; Rizzo, A; Schaerf, C; Zonta, I; Calvo, D; Filippi, A; Holtrop, M; Peremuzyan, R; Glazier, D; Ireland, D; McKinnon, B; Afanasev, D Sokhan A; Briscoe, B; Kalantarians, N; Fassi, L El; Weinstein, L; Beltrame, P; Murphy, A; Watts, D; Zana, L; Hicks, K

    2014-01-01

    MeV-GeV dark matter (DM) is theoretically well motivated but remarkably unexplored. This Letter of Intent presents the MeV-GeV DM discovery potential for a 1 m$^3$ segmented plastic scintillator detector placed downstream of the beam-dump at one of the high intensity JLab experimental Halls, receiving up to 10$^{22}$ electrons-on-target (EOT) in a one-year period. This experiment (Beam-Dump eXperiment or BDX) is sensitive to DM-nucleon elastic scattering at the level of a thousand counts per year, with very low threshold recoil energies ($\\sim$1 MeV), and limited only by reducible cosmogenic backgrounds. Sensitivity to DM-electron elastic scattering and/or inelastic DM would be below 10 counts per year after requiring all electromagnetic showers in the detector to exceed a few-hundred MeV, which dramatically reduces or altogether eliminates all backgrounds. Detailed Monte Carlo simulations are in progress to finalize the detector design and experimental set up. An existing 0.036 m$^3$ prototype based on the s...

  18. Continual Lie algebras and noncommutative counterparts of exactly solvable models

    Science.gov (United States)

    Zuevsky, A.

    2004-01-01

    Noncommutative counterparts of exactly solvable models are introduced on the basis of a generalization of Saveliev-Vershik continual Lie algebras. Examples of noncommutative Liouville and sin/h-Gordon equations are given. The simplest soliton solution to the noncommutative sine-Gordon equation is found.

  19. The optical counterpart to XMMU J004855.5-734946

    Science.gov (United States)

    Coe, M. J.; McBride, V.; Haberl, F.; Bird, A.; Udalski, A.

    2016-06-01

    The source, XMMU J004855.5-734946, reported to be currently exhibiting an X-ray outburst in ATel #9197, has an optical counterpart in the OGLE IV database, SMC720.11 13342, proposed by McBride et al (2016, in prep).

  20. On the PSR B1133+16 optical counterpart

    CERN Document Server

    Zharikov, Sergey

    2013-01-01

    The aim of this work is confirming the optical identification of PSR B1133+16, whose candidate optical counterpart was detected in Very Large Telescope (VLT) images obtained back in 2003. We used new deep optical images of the PSR B1133+16 field obtained with both the 10.4 m Gran Telescopio Canarias (GTC) and the VLT in the g' and B bands, respectively, to confirm the detection of its candidate optical counterpart and its coincidence with the most recent pulsar's radio coordinates. We did not detect any object at the position of the pulsar candidate counterpart (B~28), measured in our 2003 VLT images. However, we tentatively detected an object of comparable brightness in both the 2012 GTC and VLT images, whose position is offset by ~3.03" from that of the pulsar's candidate counterpart in the 2003 VLT images and lies along the pulsar's proper motion direction. Accounting for the time span of ~9 years between the 2012 quasi-contemporary GTC and VLT images and the 2003 VLT one, this offset is consistent with th...

  1. VARIABILITY OF OPTICAL COUNTERPARTS IN THE CHANDRA GALACTIC BULGE SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Britt, C. T.; Hynes, R. I.; Johnson, C. B.; Baldwin, A.; Collazzi, A.; Gossen, L. [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803-4001 (United States); Jonker, P. G.; Torres, M. A. P. [SRON, Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht (Netherlands); Nelemans, G. [Department of Astrophysics, IMAPP, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ, Nijmegen (Netherlands); Maccarone, T. [Department of Physics, Texas Tech University, Box 41051, Science Building, Lubbock, TX 79409-1051 (United States); Steeghs, D.; Greiss, S. [Astronomy and Astrophysics, Department of Physics, University of Warwick, Coventry, CV4 7AL (United Kingdom); Heinke, C. [Department of Physics, University of Alberta, CCIS 4-183, Edmonton, AB T6G 2E1 (Canada); Bassa, C. G. [Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); Villar, A. [Department of Physics, Massachussettes Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139-4307 (United States); Gabb, M. [Department of Physics, Florida Atlantic University, 777 Glades Road, Boca Raton, FL 33431-0991 (United States)

    2014-09-01

    We present optical light curves of variable stars consistent with the positions of X-ray sources identified with the Chandra X-ray Observatory for the Chandra Galactic Bulge Survey (GBS). Using data from the Mosaic-II instrument on the Blanco 4 m Telescope at CTIO, we gathered time-resolved photometric data on timescales from ∼2 hr to 8 days over the 3/4 of the X-ray survey containing sources from the initial GBS catalog. Among the light curve morphologies we identify are flickering in interacting binaries, eclipsing sources, dwarf nova outbursts, ellipsoidal variations, long period variables, spotted stars, and flare stars. Eighty-seven percent of X-ray sources have at least one potential optical counterpart. Twenty-seven percent of these candidate counterparts are detectably variable; a much greater fraction than expected for randomly selected field stars, which suggests that most of these variables are real counterparts. We discuss individual sources of interest, provide variability information on candidate counterparts, and discuss the characteristics of the variable population.

  2. Searching for Meanings in Finnish Athletes Career Experiences: An Existential-Narrative Approach

    DEFF Research Database (Denmark)

    Ronkainen, Noora; Ryba, Tatiana

    2013-01-01

    into how athletes bring meaning to critical situations in sports, such as injuries, overtraining, burnout, aging and retirement. Moreover, it acknowledges that spirituality can be a major source of meaning in some athletes’ lives (Nesti 2011). For this study, life story interviews were conducted with 10...... single-minded dedication from the athlete, is potentially problematic in boundary situations such as injuries and retirement. Our analysis revealed that most athletes narrated performance-oriented stories from their youth, but some re-evaluated meaning in sport when facing boundary situations...... such as injury or physical decline. The ways in which athletes constructed narratives about sport participation and the experience of aging significantly impacted the quality of their transition out of top level and how they related to sport after that. We suggest that the existential-narrative approach has high...

  3. Directional resolution of dish antenna experiments to search for WISPy dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Jaeckel, Joerg; Knirck, Stefan [Institut für theoretische Physik, Universität Heidelberg,Philosophenweg 16, 69120 Heidelberg (Germany)

    2016-01-04

    Dark matter consisting of very light and very weakly interacting particles such as axions, axion-like particles and hidden photons could be detected using reflective surfaces. On such reflectors some of the dark matter particles are converted into photons and, given a suitable geometry, concentrated on the detector. This technique offers sensitivity to the direction of the velocity of the dark matter particles. In this note we investigate how far spherical mirrors can concentrate the generated photons and what this implies for the resolution in directional detection as well as the sensitivity of discovery experiments not aiming for directional resolution. Finally we discuss an improved setup using a combination of a reflecting plane with focussing optics.

  4. Search for neutrino oscillations in the MINOS experiment by using quasi-elastic interactions

    Energy Technology Data Exchange (ETDEWEB)

    Piteira, Rodolphe [Univ. Pierre et Marie Curie, Paris (France)

    2005-09-29

    The enthusiasm of the scientific community for studying oscillations of neutrinos is equaled only by the mass of their detectors. The MINOS experiment determines and compares the near spectrum of muonic neutrinos from the NUMI beam to the far one, in order to measure two oscillation parameters: Δm$2\\atop{23}$ and sin2 (2θ23). The spectra are obtained by analyzing the charged current interactions which difficulty lies in identifying the interactions products (e.g. muons). An alternative method identifying the traces of muons, bent by the magnetic field of the detectors, and determining their energies is presented in this manuscript. The sensitivity of the detectors is optimal for the quasi-elastic interactions, for which a selection method is proposed, to study their oscillation. Even though it reduces the statistics, such a study introduces fewer systematic errors, constituting the ideal method on the long range.

  5. Directional Resolution of Dish Antenna Experiments to Search for WISPy Dark Matter

    CERN Document Server

    Jaeckel, Joerg

    2015-01-01

    Dark matter consisting of very light and very weakly interacting particles such as axions, axion-like particles and hidden photons could be detected using reflective surfaces. On such reflectors some of the dark matter particles are converted into photons and, given a suitable geometry, concentrated on the detector. This technique offers sensitivity to the direction of the velocity of the dark matter particles. In this note we investigate how far spherical mirrors can concentrate the generated photons and what this implies for the resolution in directional detection as well as the sensitivity of discovery experiments not aiming for directional resolution. Finally we discuss an improved setup using a combination of a reflecting plane with focussing optics.

  6. Directional resolution of dish antenna experiments to search for WISPy dark matter

    Science.gov (United States)

    Jaeckel, Joerg; Knirck, Stefan

    2016-01-01

    Dark matter consisting of very light and very weakly interacting particles such as axions, axion-like particles and hidden photons could be detected using reflective surfaces. On such reflectors some of the dark matter particles are converted into photons and, given a suitable geometry, concentrated on the detector. This technique offers sensitivity to the direction of the velocity of the dark matter particles. In this note we investigate how far spherical mirrors can concentrate the generated photons and what this implies for the resolution in directional detection as well as the sensitivity of discovery experiments not aiming for directional resolution. Finally we discuss an improved setup using a combination of a reflecting plane with focussing optics.

  7. Search for new physics in singly Cabibbo suppressed D decays at the Belle experiment

    Energy Technology Data Exchange (ETDEWEB)

    Levit, Dmytro; Greenwald, Daniel; Rauch, Johannes; Hoenle, Andreas; Tsipenyuk, Arseniy; Paul, Stephan [Physikdepartment E18, TU Muenchen, Garching (Germany); Collaboration: Belle-Collaboration

    2016-07-01

    The Standard Model predicts CP-Violation effects to be confined to ΔI=1/2 amplitudes in singly Cabibbo suppressed D decays. Therefore the measurement of CP violation in ΔI=3/2 amplitudes will provide evidence of new physics. In our analysis we undertake the first measurement of the branching ratio for the D{sup ±} → K{sup 0}{sub s} K{sup -+} π{sup ±} π{sup ±} π{sup 0} decay using the data sample of the Belle experiment. Additionally an amplitude analysis of the decay is performed to estimate the effect of the new physics contribution to the decay. The current status of the analysis is presented in the contribution.

  8. Searches for New Physics Using High Mass Dimuons at the CDF II Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Karagoz Unel, Muge [Northwestern Univ., Evanston, IL (United States)

    2004-12-01

    This work describes the measurement of inclusive jets cross section in the D0 experiment. This cross section is computed as a function of jet transverse momentum, in several rapidity intervals. This quantity is sensitive to the proton structure and is crucial for the determination of parton distribution functions (PDF), essentially for the gluon at high proton momentum fraction. The measurement presented here gives the first values obtained for Tevatron Run II for the cross section in several rapidity intervals, for an integrated luminosity of 143 pb-1. The results are in agreement, within the uncertainties, with theoretical Standard Model predictions, showing no evidence for new physics. This work points out the aspects of the detector which need better understanding to reach Run I precision and to constrain the PDFs.

  9. Search for rare decays of the B$0\\atop{s}$ meson with the DØ experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bernhard, Ralf Patrick [Univ. of Zurich, Irchel (Switzerland)

    2005-10-01

    This document presents the searches for the flavour-changing neutral current decays B$0\\atop{s}$ → μ+μ- and B$0\\atop{s}$s → φμ+μ- . A data set with integrated luminosity of 300 pb-1 of proton-antiproton collisions at √ s = 1 . 96 TeV collected with the DØ detector in Run II of the FERMILAB Tevatron collider is used. The former decay mode is particularly sensitive to supersymmetric extensions of the Standard Model. For the latter mode, a measurement of the branching ratio could validate the prediction of the Standard Model. In the absence of an apparent signal, a limit on the branching fraction B(B$0\\atop{s}$ → μ+μ-) can be computed by normalising the upper limit on the number of events in the B$0\\atop{s}$ signal region to the number of reconstructed B ± → J/ψ K ± events. An upper limit on the branching fraction of B(B$0\\atop{s}$ → μ+ μ- ) ≤ 3.7 × 10-7 at a 95% CL is obtained. This limit can be used to constrain models beyond the Standard Model. In models where the lightest supersymmetric particle is considered to be a dark matter candidate the limit aids in restricting the dark matter scattering cross section on nucleons. For the decay B$0\\atop{s}$ → φμ+μ- also no signal has been observed and an upper limit on the branching ratio normalised to B$0\\atop{s}$ → J/ψ φ events of B$0\\atop{s}$ B(B$0\\atop{s}$ → φ μ+ μ-)/B(B$0\\atop{s}$→J/ψφ) < 4 . 4 × 10-3 at a 95% CL is obtained. In addition, the rare decay B$0\\atop{s}$ → ψ (2 S ) φ has been observed. To measure a branching ratio, the B$0\\atop{s}$ → J/ψ φ mode was used for normalisation, while B± → ψ (2S) K± and B± → J/ψ K± modes were used as control samples. The relative branching ratio has been measured to be B(B$0

  10. Thermochemolysis and the Search for Organic Material on Mars Onboard the MOMA Experiment

    Science.gov (United States)

    Morisson, Marietta; Buch, Arnaud; Szopa, Cyril; Glavin, Daniel; Freissinet, Carolinette; Pinnick, Veronica; Goetz, Walter; Stambouli, Moncef; Belmahdi, Imene; Coll, Patrice; Stalport, Fabien; Grand, Noël; Brinckerhoff, William; Goesmann, Fred; Raulin, François; Mahaffy, Paul

    2016-04-01

    Following the Sample Analysis at Mars (SAM) experiment onboard the Curiosity rover, the Mars Organic Molecule Analyzer (MOMA) experiment onboard the future ExoMars 2018 mission will continue to investigate the organic composition of the martian subsurface. MOMA will have the advantage of extracting the sample from as deep as 2 meters below the martian surface where the deleterious effects of radiation and oxidation on organic matter are minimized. To analyse the wide range of organic compounds (volatile and non-volatile compounds) potentially present in the martian soil, MOMA includes two operational modes: UV laser desorption / ionization ion trap mass spectrometry (LDI-ITMS) and pyrolysis gas chromatography ion trap mass spectrometry (pyr-GC-ITMS). In order to analyse refractory organic compounds and chirality, samples which undergo GC-ITMS analysis may be derivatized beforhands, consisting in the reaction of the sample components with specific chemical reagents (MTBSTFA [1], DMF-DMA [2] or TMAH [3]). To prove the feasibility of the derivatization within the MOMA conditions we have adapated our laboratory procedure for the space conditions (temperature, time, pressure and size). Goal is optimize our detection limits and increase the range of the organic compounds that MOMA will be able to detect. Results of this study, show that Thermochemolysis is one of the most promising technique onboard MOMA to detect organic material. References : [1] Buch, A. et al. (2009) J Chrom. A, 43, 143-151. [2] Freissinet, C. et al. (2013) J Chrom. A, 1306, 731-740. [3] Geffroy-Rodier, C. et al. (2009) JAAP, 85, 454-459.

  11. Landau Energy Loss in Liquid Scintillator and the Search for Wifs with the LVD Experiment.

    Science.gov (United States)

    Tang, Jie

    The LVD experiment at Gran Sasso, Italy, is described, and data since the completion of the first tower (one fifth of the whole LVD) are analyzed. The dE/dx distribution of reconstructed high-energy muons in the scintillator counters is obtained. This distribution is compared with predictions by a GEANT3 Monte Carlo simulation of cosmic muons going through the LVD detector. Its shape is similar to the Landau approximation. In the data from a total running time of 245 days, 159286 clearly separable charged tracks going through the detector were reconstructed. No WIF (Weakly-Interacting Fractionally-charged particle) is observed. Since the early 1930's to the 1980's, theories on the dE/dx distribution of charged particles in matter have evolved from the fundamental work done by Bethe, Bloch, Landau, Symon, Vavilov and others with the inclusion of more precise corrections of the density effect and the shell effect. At the LVD experiment, through a procedure of gain-factor calibration at every period of 20 days, to compensate for instability and nonuniformity of the scintillator counters and their readout, the muon dE/dx distribution is measured; it conforms to the Landau approximation. The precision of the dE/dx measurement is 7.6% (one sigma).. WIF particles are speculated by modern theories. Because dE/dx is proportional to the square of the charge carried by the incident particle, any WIF going through the LVD liquid scintillator will reveal itself by its dE/dx being on the low side of the carefully calibrated muon dE/dx distribution. Calculation has shown that when the charge of a WIF is as low as {2over 3} e, it still generates enough ionization in the LVD limited streamer tubes and thus its track is as visible as a muon track in the detector. Such events are not found. Assuming a uniform flux distribution of WIF particles coming from the atmosphere, the upper limit of their flux at the LVD site is 4.4 times rm 10^{-14} cm^{-2}sterad ^{-1}sec^{-1}. (Copies

  12. Search for Higgs Bosons Decaying into Long-Lived Exotic Particles in the LHCb Experiment

    CERN Document Server

    Gauvin, Neal

    2011-01-01

    THE FOUR EXPERIMENTS of the Large Hadron Collider (LHC) at CERN have collected their first data at $\\sqrt{s}$ = 7 TeV, hailing an exciting era in particle physics. The LHCb detector is a single-arm forward spectrometer, dedicated to precision measurements of $\\cal{CP}$ violation, as well as to the study of rare $b$-hadron decays. In this work the excellent capability of the detector to reconstruct decay vertices in the region close to the interaction point with a resolution of few tenths of microns has been exploited. To achieve such a resolution, a precise measurement of the charged particle trajectories is essential. The Inner Tracker is the detector that provides tracking information for the particles flying in the innermost part of LHCb. While preparing this thesis, I contributed to the construction of the Inner Tracker by setting up an assembly procedure for the twelve detector boxes. This included the preparation and thorough testing of numerous pieces, among them 386 sensor modules. Inner Tracker dete...

  13. Search for Cosmic-Ray Antiparticles with Balloon-borne and Space-borne Experiments

    CERN Document Server

    von Doetinchem, Ph

    2009-01-01

    This thesis discusses two different approaches for the measurement of cosmic-ray antiparticles in the GeV to TeV energy range. The first part of this thesis discusses the prospects of antiparticle flux measurements with the proposed PEBS detector. The project allots long duration balloon flights at one of Earth's poles at an altitude of 40 km. GEANT4 simulations were carried out which determine the atmospheric background and attenuation especially for antiparticles. The second part covers the AMS-02 experiment which will be installed in 2010 on the International Space Station at an altitude of about 400 km for about three years to measure cosmic rays without the influence of Earth's atmosphere. The present work focuses on the anticoincidence counter system (ACC). The ACC is needed to reduce the trigger rate during periods of high fluxes and to reject external particles crossing the tracker from the side or particles resulting from interactions within the detector which would otherwise disturb the clean charge...

  14. Search for Contact Interactions in Dilepton Final State in the CMS Experiment: Generator-Level Studies

    Science.gov (United States)

    Zaleski, Shawn

    2017-01-01

    A set of contact interaction (CI) Monte Carlo events, for which Standard Model Drell-Yan events are background, are generated using a leading-order parton-shower generator, Pythia8. We consider three isoscalar models with three different helicity structures, left-left (LL), left-right/right-left (LR), and right­right (RR), each with destructive and constructive interference. For each of these models, 150,000 events are generated for analysis of CI interactions in the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) with a centre of mass energy of 13 TeV. This study is a generator level study, and detector effects are accounted for by application of kinematic cuts on the generator-level quantities rather than application of a detailed detector simulation package (e.g. GEANT). Distributions of dilepton invariant mass, Collins-Soper angle, and the forward-backward asymmetry are compared with those arising from pure Drell-Yan events.

  15. Search for physics beyond the standard electroweak model with the WITCH experiment

    CERN Document Server

    Van Gorp, Simon

    A measurement of the $\\beta$-neutrino angular correlation coefficient $a$ yields information on possible exotic couplings in the weak interaction. To this end the energy distribution of the recoiling daughter nucleus after $\\beta$-decay, which depends on $a$, is measured precisely. Any deviation of the measured distribution with the one expected from the Standard Model can reveal new physics. If no deviation is found stringent limits can be set on the possible presence of different types of new physics beyond the Standard Model. The WITCH experiment, located at ISOLDE, CERN aims to determine $a$ with a final precision below 1%. $\\\\$ Ion bunches are created with REXTRAP and injected in the WITCH setup. The energy of these ion bunches is pulsed down in the Pulsed Drift Tube section, prior to the capture of the ions in the first of two Penning traps. The motion of the radioactive ions is cooled before the transfer to a second Penning trap, the decay trap, which acts as the scattering-free sou...

  16. OMC camera experiment for INTEGRAL and search for Compton GRO BATSE LOCBURST optical transients

    Science.gov (United States)

    Rezek, Tomáš; Hudec, René; Hroch, Filip; Soldán, Jan; Mas-Hesse, Miguel; Giménez, Alvaro

    1998-05-01

    The test camera of the Optical Monitoring Camera (OMC) experiment for INTEGRAL spacecraft achieving an angular pixel size of 18 arcsec and a field of view 7.5°×5.1° has been successfully developed and tested at the Astronomical Institute Ondřejov. The test camera is able to provide imaging down to 15 mag over the whole field of view within one exposure of 300 seconds. Although developed primarily to test the OMC performance and help with software development, this device is ideally suited for use as a ground-based camera for sites where Compton Gamma Ray Observatory BATSE Locburst triggers are followed-up in the optical waveband and also for wide-field sky monitoring in general. The low cost of this camera makes it possible to duplicate the system at a number of observing sites. A chart and a corresponding CCD-image for the BACODINE Locburst Position 6368 taken with the OMC test camera at Ondřejov observatory are also presented. The image taken 18 hours after the trigger was computer-blinked with the frame taken 30 days later. No optical activity has been found down to 13.5 mag.

  17. Application of Grid technologies and search for exotics physics with the ATLAS experiment at the LHC

    CERN Document Server

    March, Luis; Ros, Eduardo

    The work presented in this thesis has been performed within the ATLAS (A Toroidal LHC ApparatuS) collaboration. Two subjects have been investigated. One subject is the Computing System Commissioning (CSC) production using an instance of the Production System (ProdSys), called Lexor, and the test of the ATLAS Distributed Analysis (ADA) using ProdSys. The other subject is the sim- ulation and subsequent analysis of processes involving new particles predicted by the Little Higgs model within the ATLAS detector. An introduction to the Standard Model (SM), the Large Hadron Collider (LHC) and the ATLAS experiment, software and computing is given in chapter 1. The problems of the SM are discussed and some proposed solutions are reviewed. The SM introduction is followed by an overview of LHC and ATLAS. The main AT- LAS subsystems are described and the ATLAS software and computing model is discussed. Many physics processes within and beyond the Standard Model involve b-quark decays. New heavy particles, expected in mo...

  18. Search for BSM decays of SM Higgs and non-resonant di-Higgs results in ATLAS and CMS experiments

    CERN Document Server

    Geng, Cong; The ATLAS collaboration

    2016-01-01

    Report the searches for BSM decays of SM Higgs from ATLAS and CMS results with RUN1 and RUN2 datasets, which includes search for LFV, NMSSM and H to invisible in SM Higgs decays. In this report, I will also report the results of search for non-resonant di-Higgs in ATLAS and CMS.

  19. Simulations of the muon-induced neutron background of the EDELWEISS-II experiment for Dark Matter search

    Energy Technology Data Exchange (ETDEWEB)

    Horn, O.M.

    2007-12-21

    In modern astroparticle physics and cosmology, the nature of Dark Matter is one of the central problems. Particle Dark Matter in form of WIMPs is favoured among many proposed candidates. The EDELWEISS direct Dark Matter search uses Germanium bolometers to detect these particles by nuclear recoils. Here, the use of two signal channels on an event-by-event basis, namely the heat and ionisation signal, enables the detectors to discriminate between electron and nuclear recoils. This technique leaves neutrons in the underground laboratory as the main background for the experiment. Besides ({alpha},n) reactions of natural radioactivity, neutrons are produced in electromagnetic and hadronic showers induced by cosmic ray muons in the surrounding rock and shielding material of the Germanium crystals. To reach high sensitivities, the EDELWEISS-II experiment, as well as other direct Dark Matter searches, has to efficiently suppress this neutron background. The present work is devoted to study the muon-induced neutron flux in the underground laboratory LSM and the interaction rate within the Germanium crystals by using the Monte Carlo simulation toolkit Geant4. To ensure reliable results, the implemented physics in the toolkit regarding neutron production is tested in a benchmark geometry and results are compared to experimental data and other simulation codes. Also, the specific energy and angular distribution of the muon flux in the underground laboratory as a consequence of the asymmetric mountain overburden is implemented. A good agreement of the simulated muon flux is shown in a comparison to preliminary experimental data obtained with the EDELWEISS-II muon veto system. Furthermore, within a detailed geometry of the experimental setup, the muon-induced background rate of nuclear recoils in the bolometers is simulated. Coincidences of recoil events in the Germanium with an energy deposit of the muoninduced shower in the plastic scintillators of the veto system are studied

  20. LHCb: Search for the rare decays $B^0_{(s)} \\to \\mu^+\\mu^-$ with the LHCb Experiment

    CERN Multimedia

    Perrin-Terrin, M

    2011-01-01

    A review of the search for the very rare decays $B^{0}_{s} \\rightarrow \\mu^+ \\mu^-$ and $B^{0} \\rightarrow \\mu^+ \\mu^-$ with the LHCb experiment is presented. These decays are suppressed within the Standard Model as they can only occur via helicity suppressed loop diagrams. However, their amplitudes can be significantly different in many New Physics scenarios, especially in those with an extended Higgs sector. Therefore, these decays are a sensitive probe of physics beyond the Standard Model. The study is performed using $\\sim 37$ $pb^{-1}$ of pp collisions at $\\sqrt{s}$ = 7 TeV collected by the experiment at the Large Hadron Collider at CERN. For these dimuon decays the LHCb has reached sensitivities similar to the best existing limits. The resulting upper limits are $\\mathcal{B}(B^{0}_{s} \\rightarrow \\mu^+ \\mu^-)<$ 56 $\\times$ $10^{-9}$ and $\\mathcal{B}(B^{0} \\rightarrow \\mu^+ \\mu^-)<$ 15 $\\times$ $10^{-9}$ at $95\\%$ confidence level. With the number of pp colisions expected in 2011 the LHCb will ...

  1. Search for sub-eV sterile neutrinos in the precision multiple baselines reactor antineutrino oscillation experiments

    Directory of Open Access Journals (Sweden)

    Shu Luo

    2015-10-01

    Full Text Available According to different effects on neutrino oscillations, the unitarity violation in the MNSP matrix can be classified into the direct unitarity violation and the indirect unitarity violation which are induced by the existence of the light and the heavy sterile neutrinos respectively. Of which sub-eV sterile neutrinos are of most interesting. We study in this paper the possibility of searching for sub-eV sterile neutrinos in the precision reactor antineutrino oscillation experiments with three different baselines at around 500 m, 2 km and 60 km. We find that the antineutrino survival probabilities obtained in the reactor experiments are sensitive only to the direct unitarity violation and offer very concentrated sensitivity to the two parameters θ14 and Δm412. If such light sterile neutrinos do exist, the active–sterile mixing angle θ14 could be acquired by the combined rate analysis at all the three baselines and the mass-squared difference Δm412 could be obtained by taking the Fourier transformation to the L/E spectrum. Of course, for such measurements to succeed, both high energy resolution and large statistics are essentially important.

  2. Search for exotic resonances in the decay $B^+ \\rightarrow J/\\psi \\; \\omega K^+$ in the LHCb experiment at CERN

    CERN Document Server

    Andreassi, Guido; Alves Junior, Antonio Augusto

    “The expression \\textit{exotic resonances} indicates those states whose characteristics don’t fit in the ordinary mesons nor baryons scheme.\\\\ In this thesis an analysis of the $J/\\psi \\; \\omega$ invariant mass in the decay $B^+ \\rightarrow (J/\\psi \\rightarrow \\mu^+ \\mu^-) \\; (\\omega \\rightarrow \\pi^+ \\pi^- \\pi^0) \\; K^+$ is performed in order to search for such resonances, in particular the X(3872), previously observed in this final state by the BaBar experiment in 2010 at the Stanford Linear Accelerator Center [10]. The nature of this particle is still under study: different theoretical models were proposed. Thus, further experimental measurements are needed in order to improve the understanding of its characteristics. The present analysis is performed on data collected by the LHCb experiment at the Large Hadron Collider at CERN during 2011 and 2012. It is structured as follows: $$ $$• the events are reconstructed and selected in order to reduce as much as possible the background contamination;$$ $$�...

  3. Search for electroweak production of the top quark in the D diameter experiment; Recherche de la production electrofaible de quark top dans l'experience D diametre

    Energy Technology Data Exchange (ETDEWEB)

    Agelou, M

    2005-05-01

    This thesis deals with the search for a signal of the electroweak production of the top quark. This signal is made up of a high energy muon issued from the decay of a W, itself produced by a top quark. As the neutrino escapes from the detection system, some transverse energy is expected to be missing and at least 2 jets must be released with at least one jet of B. In the first chapter the author presents the standard model and reviews what physics can be made with an accelerator like the Tevatron. The second chapter presents the quest for the top quark and its discovery at the Tevatron in 1995. The third chapter is dedicated to the phenomenology of the electroweak production of the top. The chapter four presents the Tevatron and the different detectors involved in the D0 experiment. The chapter five is dedicated to the tools necessary to perform data analysis, it means to assess the corrections to apply to muon momentum, to simulated background events and to algorithms of B jet identification. The last chapter is dedicated to the search analysis of the top electroweak production in the muonic channel. 2 analysis are described: one using 158 pb{sup -1} of data and that is based on the presence of one muon in a jet to identify a B jet and the other one operating on 230 pb{sup -1} of data and that is based on a more efficient algorithm of B jet identification. This work allows us to propose a maximum value of 22.8 pb for the electroweak production cross-section of the top quark when s and t channels are combined. (A.C.)

  4. Direct searches for non-baryonic dark matter; Experiences de detection directe de la matiere sombre non baryonique

    Energy Technology Data Exchange (ETDEWEB)

    Di Stefano, Philippe E. [Max-Planck-Institut fuer Physik, Munich (Germany)]. E-mail: distefano@mppmu.mpg.de

    2001-10-01

    Since the mid-1980s, non-accelerator particle physics experiments have been searching for weakly interacting massive particles which could solve the dark matter enigma first pointed out some 70 years ago. The low event rate and energies expected pose a formidable experimental challenge. The first detectors were ionization devices, soon followed by scintillation detectors able to reject a small portion of the photon and electron radioactive backgrounds. The performance of these early generations of detectors has now been matched by new cryogenic detectors in which a simultaneous reading of phonons and charge allows a very efficient rejection of the background. These devices, along with recently developed simultaneous phonon and scintillation techniques could provide cryogenic devices with a decisive advantage. (author) [French] La question astrophysique de la matiere sombre, posee dans les annees trente, attire depuis une quinzaine d'annees des experiences de physique des particules hors accelerateur tentant d'y repondre par la mise en evidence de particules lourdes et interagissant faiblement. Le faible taux et la basse energie des evenements attendus rendent la tache ardue. Les premiers detecteurs employes furent a ionisation, puis a scintillation, ceux-ci disposant d'une methode rudimentaire pour rejeter le fond electromagnetique. Ces deux premieres generations d'experiences massives sont aujourd'hui rattrapees par des nouveaux detecteurs cryogeniques associant une mesure de l'ionisation a un signal phonons, qui permettent de rejeter le fond electromagnetique tres efficacement. Ces dispositifs, et de recents developpements de mesure simultanee de scintillation et de phonons, pourraient donner l'avantage aux detecteurs cryogeniques. (author)

  5. Optical Counterparts of Ultra Luminous X-ray Sources

    CERN Document Server

    Gutíerrez, C M

    2006-01-01

    We present optical identification and characterization of counterparts of four objects previously catalogued as ultra-luminous X-ray sources. The objects were selected from the Colbert & Ptak (2002) catalogue. The optical counterparts are identified as point-like objects with magnitudes in the range \\~17-19. The optical spectra of three of the sources (IXO 32, 37 and 40) show the presence of emission lines typical of quasars. The position of these lines allows a precise estimation of their redshifts (2.769, 0.567 and 0.789 for IXO 32, 37 and 40 respectively). The fourth X-ray source, IXO35, is associated with a red object that has a spectrum typical of an M star in our Galaxy. These identifications are useful for building clean samples of ULX sources, selecting suitable targets for future observations and performing statistical studies on the different populations of X-ray sources.

  6. The Optical Counterpart of M101 ULX-1

    Science.gov (United States)

    Kuntz, K. D.; Gruendi, Robert A.; Chu, You-Hua; Chen, C.-H. Rosie; Still, Martin; Mukai, Koji; Musuotzky, Richard F.

    2004-01-01

    We have identified the optical counterpart of the Ultra-Luminous X-ray source Ml0l ULX-1 (CX- OKM101 J140332.74+542102), by comparing HST ACS images with Chandra ACIS-S images. The optical counterpart has V= 23.75 and colours consistent with those for a mid-B supergiant. Archival WFPC2 observations show that the source brightness is constant to within approximately 0.1 mag. The physical association of this source with the ULX is confirmed by Gemini GMOS spectroscopic observations which show spatially unresolved He II lambda4686 and He I lambda5876 emission. These results suggest that M10l ULX-1 is a HMXB but deep spectroscopic monitoring observations are needed to determine the detailed properties of this system.

  7. A STAFF DEVELOPMENT PROGRAMME FOR BRITISH COUNCIL ELT PROJECT COUNTERPARTS

    Institute of Scientific and Technical Information of China (English)

    Michael; Hall

    1997-01-01

    In British Council-managed ELT projects in Chinese universities,Chinese project counterparts areselected from among the English-language teaching staff of the University.They work alongside aBritish Council-recruited lecturer(BCL)in developing whatever it is the project has been set up tocreate:a syllabus,teaching materials,a course,etc.During the lifetime of the project eachcounterpart is sent for a year’s postgraduate training(typically an MA in applied Linguistics)at aBritish university,the rationale being that the combination of training on the job and in the UK willequip them to take over the running of the project and ensure its long-term sustainability.This paperlooks at the staff development of the counterparts prior to their UK training.

  8. No-broadcasting theorem and its classical counterpart.

    Science.gov (United States)

    Kalev, Amir; Hen, Itay

    2008-05-30

    Although it is widely accepted that "no-broadcasting"-the nonclonability of quantum information-is a fundamental principle of quantum mechanics, an impossibility theorem for the broadcasting of general density matrices has not yet been formulated. In this Letter, we present a general proof for the no-broadcasting theorem, which applies to arbitrary density matrices. The proof relies on entropic considerations, and as such can also be directly linked to its classical counterpart, which applies to probabilistic distributions of statistical ensembles.

  9. A Search for WIMP Dark Matter Using an Optimized Chi-square Technique on the Final Data from the Cryogenic Dark Matter Search Experiment (CDMS II)

    Energy Technology Data Exchange (ETDEWEB)

    Manungu Kiveni, Joseph [Syracuse Univ., NY (United States)

    2012-12-01

    This dissertation describes the results of a WIMP search using CDMS II data sets accumulated at the Soudan Underground Laboratory in Minnesota. Results from the original analysis of these data were published in 2009; two events were observed in the signal region with an expected leakage of 0.9 events. Further investigation revealed an issue with the ionization-pulse reconstruction algorithm leading to a software upgrade and a subsequent reanalysis of the data. As part of the reanalysis, I performed an advanced discrimination technique to better distinguish (potential) signal events from backgrounds using a 5-dimensional chi-square method. This dataanalysis technique combines the event information recorded for each WIMP-search event to derive a backgrounddiscrimination parameter capable of reducing the expected background to less than one event, while maintaining high efficiency for signal events. Furthermore, optimizing the cut positions of this 5-dimensional chi-square parameter for the 14 viable germanium detectors yields an improved expected sensitivity to WIMP interactions relative to previous CDMS results. This dissertation describes my improved (and optimized) discrimination technique and the results obtained from a blind application to the reanalyzed CDMS II WIMP-search data.

  10. X-ray Counterparts of Millisecond Pulsars in Globular Clusters

    CERN Document Server

    Becker, W; Prinz, T

    2010-01-01

    We have systematically studied the X-ray emission properties of globular cluster millisecond pulsars in order to evaluate their spectral properties and luminosities in a uniform way. Cross-correlating the radio timing positions of the cluster pulsars with the high resolution Chandra images revealed 31 X-ray counterparts identified in nine different globular cluster systems, including those in 47 Tuc. Timing analysis has been performed for all sources corresponding to the temporal resolution available in the archival Chandra data. Making use of unpublished data on M28, M4 and NGC 6752 allowed us to obtain further constraints for the millisecond pulsar counterparts located in these clusters. Counting rate and energy flux upper limits were computed for those 36 pulsars for which no X-ray counterparts could be detected. Comparing the X-ray and radio pulse profiles of PSR J1821-2452 in M28 and the 47 Tuc pulsars PSR J0024-7204D,O,R indicated some correspondence between both wavebands. The X-ray efficiency of the g...

  11. The HIPASS Catalogue: III - Optical Counterparts & Isolated Dark Galaxies

    CERN Document Server

    Doyle, M T; Rohde, D J; Pimbblet, K A; Read, M; Meyer, M J; Zwaan, M A; Ryan-Weber, E; Stevens, J; Koribalski, B S; Webster, R L; Staveley-Smith, L; Barnes, D G; Howlett, M; Kilborn, V A; Waugh, M; Pierce, M J; Bhathal, R; De Blok, W J G; Disney, M J; Ekers, R D; Freeman, K C; García, D A; Gibson, B K; Harnett, J I; Henning, P A; Jerjen, H; Kesteven, M J; Knezek, P M; Mader, S; Marquarding, M; Minchin, R F; O'Brien, J; Oosterloo, T; Price, R M; Putman, M E; Ryder, S D; Sadler, E M; Stewart, I M; Stootman, F; Wright, A E; Doyle, Marianne T.

    2005-01-01

    We present the largest catalogue to date of optical counterparts for HI radio-selected galaxies, Hopcat. Of the 4315 HI radio-detected sources from the HI Parkes All Sky Survey (Hipass) catalogue, we find optical counterparts for 3618 (84%) galaxies. Of these, 1798 (42%) have confirmed optical velocities and 848 (20%) are single matches without confirmed velocities. Some galaxy matches are members of galaxy groups. From these multiple galaxy matches, 714 (16%) have confirmed optical velocities and a further 258 (6%) galaxies are without confirmed velocities. For 481 (11%), multiple galaxies are present but no single optical counterpart can be chosen and 216 (5%) have no obvious optical galaxy present. Most of these 'blank fields' are in crowded fields along the Galactic plane or have high extinctions. Isolated 'Dark galaxy' candidates are investigated using an extinction cut of ABj < 1 mag and the blank fields category. Of the 3692 galaxies with an ABj extinction < 1 mag, only 13 are also blank fields. ...

  12. A search for optical counterparts of the complex Vela X system

    CERN Document Server

    Marubini, T E; Venter, C; de Jager, O C

    2015-01-01

    The pulsar wind nebula (PWN) associated with the Vela pulsar is a bright source in the radio, X-ray and gamma-ray bands, but not in the optical. This source is very near, lying at a distance of 290 pc, as inferred from the radio and optical parallax measurements of the pulsar. Knowledge of the brightness and structure of the Vela PWN in optical is important in order to constrain the underlying particle spectrum (and possibly the B-field properties and particle losses) associated with this extended source. We use results from the Digital Sky Survey, as well as results obtained using the SAAO 1.0 m telescope equipped with an imaging CCD (STE4) and BV filters, in an attempt to measure optical radiation from Vela X. To enlarge our field of view, we constructed a mosaic consisting of 3 x 3 frames around the pulsar position. We present spectral measurements from the High Energy Stereoscopic System (H.E.S.S.), Fermi Large Area Telescope (LAT), ASCA, Hubble Space Telescope (HST), Very Large Telescope (VLT), New Techn...

  13. Implementation and Testing of the First Prompt Search for Gravitational Wave Transients with Electromagnetic Counterparts

    Science.gov (United States)

    Abadie, J.; Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M.; Accadia, T.; Acernese, F.; Adams, C.; Adhikari, R.; Affeldt, C.; hide

    2012-01-01

    Aims. A transient astrophysical event observed in both gravitational wave (GW) and electromagnetic (EM) channels would yield rich scientific rewards. A first program initiating EM follow-ups to possible transient GW events has been developed and exercised by the LIGO and Virgo community in association with several partners. In this paper, we describe and evaluate the methods used to promptly identify and localize GW event candidates and to request images of targeted sky locations. Methods. During two observing periods (Dec. 17, 2009 to Jan. 8, 2010 and Sep. 2 to Oct. 20, 2010), a low-latency analysis pipeline was used to identify GW event candidates and to reconstruct maps of possible sky locations. A catalog of nearby galaxies and MilkyWay globular clusters was used to select the most promising sky positions to be imaged, and this directional information was delivered to EM observatories with time lags of about thirty minutes. A Monte Carlo simulation has been used to evaluate the low-latency GW pipeline's ability to reconstruct source positions correctly. Results. For signals near the detection threshold, our low-latency algorithms often localized simulated GW burst signals to tens of square degrees, while neutron star/neutron star inspirals and neutron star/black hole inspirals were localized to a few hundred square degrees. Localization precision improves for moderately stronger signals. The correct sky location of signals well above threshold and originating from nearby galaxies may be observed with 50% or better probability with a few pointings of wide-field telescopes.

  14. Search for extragalactic astrophysical counterparts of IceCube neutrino events

    CERN Document Server

    Moharana, Reetanjali; Razzaque, Soebur

    2016-01-01

    Detection of 54 very high-energy (VHE) neutrinos by the IceCube Neutrino Observatory has opened a new chapter in multi-messenger astronomy. However due to large errors in measuring the directions of the neutrino shower-type events, which dominate the current event list, it is difficult to identify their astrophysical sources. We perform cross-correlation study of IceCube neutrino events with extragalactic candidate sources using X-ray and gamma-ray selected source catalogues such as Swift-BAT, 3LAC and TeV-Cat. We apply different cuts on the X-ray and gamma-ray fluxes of the sources in these catalogs, and use different source classes in order to study correlation. We use invariant statistic and Monte Carlo simulations to evaluate statistical significance of any correlation.

  15. Implementation and testing of the first prompt search for gravitational wave transients with electromagnetic counterparts

    NARCIS (Netherlands)

    Abadie, J.; et al., [Unknown; Homan, J.; Fender, R.; Stappers, B.W.; Swinbank, J.; Wijers, R.A.M.J.

    2012-01-01

    Aims: A transient astrophysical event observed in both gravitational wave (GW) and electromagnetic (EM) channels would yield rich scientific rewards. A first program initiating EM follow-ups to possible transient GW events has been developed and exercised by the LIGO and Virgo community in associati

  16. Implementation and testing of the first prompt search for electromagnetic counterparts to gravitational wave transients

    CERN Document Server

    Abadie, J; Abbott, R; Abbott, T D; Abernathy, M; Accadia, T; Acernese, F; Adams, C; Adhikari, R; Affeldt, C; Ajith, P; Allen, B; Allen, G S; Ceron, E Amador; Amariutei, D; Amin, R S; Anderson, S B; Anderson, W G; Arai, K; Arain, M A; Araya, M C; Aston, S M; Astone, P; Atkinson, D; Aufmuth, P; Aulbert, C; Aylott, B E; Babak, S; Baker, P; Ballardin, G; Ballmer, S; Barker, D; Barone, F; Barr, B; Barriga, P; Barsotti, L; Barsuglia, M; Barton, M A; Bartos, I; Bassiri, R; Bastarrika, M; Basti, A; Batch, J; Bauchrowitz, J; Bauer, Th S; Bebronne, M; Behnke, B; Beker, M G; Bell, A S; Belletoile, A; Belopolski, I; Benacquista, M; Berliner, J M; Bertolini, A; Betzwieser, J; Beveridge, N; Beyersdorf, P T; Bilenko, I A; Billingsley, G; Birch, J; Biswas, R; Bitossi, M; Bizouard, M A; Black, E; Blackburn, J K; Blackburn, L; Blair, D; Bland, B; Blom, M; Bock, O; Bodiya, T P; Bogan, C; Bondarescu, R; Bondu, F; Bonelli, L; Bonnand, R; Bork, R; Born, M; Boschi, V; Bose, S; Bosi, L; Bouhou, B; Braccini, S; Bradaschia, C; Brady, P R; Braginsky, V B; Branchesi, M; Brau, J E; Breyer, J; Briant, T; Bridges, D O; Brillet, A; Brinkmann, M; Brisson, V; Britzger, M; Brooks, A F; Brown, D A; Brummit, A; Bulik, T; Bulten, H J; Buonanno, A; Burguet--Castell, J; Burmeister, O; Buskulic, D; Buy, C; Byer, R L; Cadonati, L; Cagnoli, G; Cain, J; Calloni, E; Camp, J B; Campsie, P; Cannizzo, J; Cannon, K; Canuel, B; Cao, J; Capano, C D; Carbognani, F; Caride, S; Caudill, S; Cavaglià, M; Cavalier, F; Cavalieri, R; Cella, G; Cepeda, C; Cesarini, E; Chaibi, O; Chalermsongsak, T; Chalkley, E; Charlton, P; Chassande-Mottin, E; Chelkowski, S; Chen, Y; Chincarini, A; Chiummo, A; Cho, H; Christensen, N; Chua, S S Y; Chung, C T Y; Chung, S; Ciani, G; Clara, F; Clark, D E; Clark, J; Clayton, J H; Cleva, F; Coccia, E; Cohadon, P -F; Colacino, C N; Colas, J; Colla, A; Colombini, M; Conte, A; Conte, R; Cook, D; Corbitt, T R; Cordier, M; Cornish, N; Corsi, A; Costa, C A; Coughlin, M; Coulon, J -P; Couvares, P; Coward, D M; Coyne, D C; Creighton, J D E; Creighton, T D; Cruise, A M; Cumming, A; Cunningham, L; Cuoco, E; Cutler, R M; Dahl, K; Danilishin, S L; Dannenberg, R; D'Antonio, S; Danzmann, K; Dattilo, V; Daudert, B; Daveloza, H; Davier, M; Davies, G; Daw, E J; Day, R; Dayanga, T; De Rosa, R; DeBra, D; Debreczeni, G; Degallaix, J; Del Pozzo, W; del Prete, M; Dent, T; Dergachev, V; DeRosa, R; DeSalvo, R; Dhillon, V; Dhurandhar, S; Di Fiore, L; Di Lieto, A; Di Palma, I; Emilio, M Di Paolo; Di Virgilio, A; Díaz, M; Dietz, A; Donovan, F; Dooley, K L; Dorsher, S; Drago, M; Drever, R W P; Driggers, J C; Du, Z; Dumas, J -C; Dwyer, S; Eberle, T; Edgar, M; Edwards, M; Effler, A; Ehrens, P; Endrőczi, G; Engel, R; Etzel, T; Evans, K; Evans, M; Evans, T; Factourovich, M; Fafone, V; Fairhurst, S; Fan, Y; Farr, B F; Farr, W; Fazi, D; Fehrmann, H; Feldbaum, D; Ferrante, I; Fidecaro, F; Finn, L S; Fiori, I; Fisher, R P; Flaminio, R; Flanigan, M; Foley, S; Forsi, E; Forte, L A; Fotopoulos, N; Fournier, J -D; Franc, J; Frasca, S; Frasconi, F; Frede, M; Frei, M; Frei, Z; Freise, A; Frey, R; Fricke, T T; Fridriksson, J K; Friedrich, D; Fritschel, P; Frolov, V V; Fulda, P J; Fyffe, M; Galimberti, M; Gammaitoni, L; Ganija, M R; Garcia, J; Garofoli, J A; Garufi, F; Gáspár, M E; Gemme, G; Geng, R; Genin, E; Gennai, A; Gergely, L Á; Ghosh, S; Giaime, J A; Giampanis, S; Giardina, K D; Giazotto, A; Gill, C; Goetz, E; Goggin, L M; González, G; Gorodetsky, M L; Goßler, S; Gouaty, R; Graef, C; Granata, M; Grant, A; Gras, S; Gray, C; Gray, N; Greenhalgh, R J S; Gretarsson, A M; Greverie, C; Grosso, R; Grote, H; Grunewald, S; Guidi, G M; Guido, C; Gupta, R; Gustafson, E K; Gustafson, R; Ha, T; Hage, B; Hallam, J M; Hammer, D; Hammond, G; Hanks, J; Hanna, C; Hanson, J; Harms, J; Harry, G M; Harry, I W; Harstad, E D; Hartman, M T; Haughian, K; Hayama, K; Hayau, J -F; Hayler, T; Heefner, J; Heidmann, A; Heintze, M C; Heitmann, H; Hello, P; Hendry, M A; Heng, I S; Heptonstall, A W; Herrera, V; Hewitson, M; Hild, S; Hoak, D; Hodge, K A; Holt, K; Homan, J; Hong, T; Hooper, S; Hosken, D J; Hough, J; Howell, E J; Hughey, B; Husa, S; Huttner, S H; Huynh-Dinh, T; Ingram, D R; Inta, R; Isogai, T; Ivanov, A; Izumi, K; Jacobson, M; Jang, H; Jaranowski, P; Johnson, W W; Jones, D I; Jones, G; Jones, R; Ju, L; Kalmus, P; Kalogera, V; Kamaretsos, I; Kandhasamy, S; Kang, G; Kanner, J B; Katsavounidis, E; Katzman, W; Kaufer, H; Kawabe, K; Kawamura, S; Kawazoe, F; Kells, W; Keppel, D G; Keresztes, Z; Khalaidovski, A; Khalili, F Y; Khazanov, E A; Kim, B; Kim, C; Kim, D; Kim, H; Kim, K; Kim, N; Kim, Y -M; King, P J; Kinsey, M; Kinzel, D L; Kissel, J S; Klimenko, S; Kokeyama, K; Kondrashov, V; Kopparapu, R; Koranda, S; Korth, W Z; Kowalska, I; Kozak, D; Kringel, V; Krishnamurthy, S; Krishnan, B; Królak, A; Kuehn, G; Kumar, R; Kwee, P; Laas-Bourez, M; Lam, P K; Landry, M; Lang, M; Lantz, B; Lastzka, N; Lawrie, C; Lazzarini, A; Leaci, P; Lee, C H; Lee, H M; Leindecker, N; Leong, J R; Leonor, I; Leroy, N; Letendre, N; Li, J; Li, T G F; Liguori, N; Lindquist, P E; Lockerbie, N A; Lodhia, D; Lorenzini, M; Loriette, V; Lormand, M; Losurdo, G; Luan, J; Lubinski, M; Lück, H; Lundgren, A P; Macdonald, E; Machenschalk, B; MacInnis, M; Macleod, D M; Mageswaran, M; Mailand, K; Majorana, E; Maksimovic, I; Man, N; Mandel, I; Mandic, V; Mantovani, M; Marandi, A; Marchesoni, F; Marion, F; Márka, S; Márka, Z; Markosyan, A; Maros, E; Marque, J; Martelli, F; Martin, I W; Martin, R M; Marx, J N; Mason, K; Masserot, A; Matichard, F; Matone, L; Matzner, R A; Mavalvala, N; Mazzolo, G; McCarthy, R; McClelland, D E; McDaniel, P; McGuire, S C; McIntyre, G; McKechan, D J A; Meadors, G D; Mehmet, M; Meier, T; Melatos, A; Melissinos, A C; Mendell, G; Menendez, D; Mercer, R A; Merill, L; Meshkov, S; Messenger, C; Meyer, M S; Miao, H; Michel, C; Milano, L; Miller, J; Minenkov, Y; Mitrofanov, V P; Mitselmakher, G; Mittleman, R; Miyakawa, O; Moe, B; Moesta, P; Mohan, M; Mohanty, S D; Mohapatra, S R P; Moraru, D; Moreno, G; Morgado, N; Morgia, A; Mori, T; Mosca, S; Mossavi, K; Mours, B; Mow--Lowry, C M; Mueller, C L; Mueller, G; Mukherjee, S; Mullavey, A; Müller-Ebhardt, H; Munch, J; Murray, P G; Mytidis, A; Nash, T; Naticchioni, L; Nawrodt, R; Necula, V; Nelson, J; Newton, G; Nishida, E; Nishizawa, A; Nocera, F; Nolting, D; Nuttall, L; Ochsner, E; O'Dell, J; Oelker, E; Ogin, G H; Oh, J J; Oh, S H; Oldenburg, R G; O'Reilly, B; O'Shaughnessy, R; Osthelder, C; Ott, C D; Ottaway, D J; Ottens, R S; Overmier, H; Owen, B J; Page, A; Pagliaroli, G; Palladino, L; Palomba, C; Pan, Y; Pankow, C; Paoletti, F; Papa, M A; Parisi, M; Pasqualetti, A; Passaquieti, R; Passuello, D; Patel, P; Pathak, D; Pedraza, M; Peiris, P; Pekowsky, L; Penn, S; Peralta, C; Perreca, A; Persichetti, G; Phelps, M; Pickenpack, M; Piergiovanni, F; Pietka, M; Pinard, L; Pinto, I M; Pitkin, M; Pletsch, H J; Plissi, M V; Poggiani, R; Pöld, J; Postiglione, F; Prato, M; Predoi, V; Price, L R; Prijatelj, M; Principe, M; Privitera, S; Prix, R; Prodi, G A; Prokhorov, L; Puncken, O; Punturo, M; Puppo, P; Quetschke, V; Raab, F J; Rabeling, D S; Rácz, I; Radkins, H; Raffai, P; Rakhmanov, M; Ramet, C R; Rankins, B; Rapagnani, P; Rapoport, S; Raymond, V; Re, V; Redwine, K; Reed, C M; Reed, T; Regimbau, T; Reid, S; Reitze, D H; Ricci, F; Riesen, R; Riles, K; Robertson, N A; Robinet, F; Robinson, C; Robinson, E L; Rocchi, A; Roddy, S; Rodriguez, C; Rodruck, M; Rolland, L; Rollins, J; Romano, J D; Romano, R; Romie, J H; Rosińska, D; Röver, C; Rowan, S; Rüdiger, A; Ruggi, P; Ryan, K; Ryll, H; Sainathan, P; Sakosky, M; Salemi, F; Sammut, L; de la Jordana, L Sancho; Sandberg, V; Sankar, S; Sannibale, V; Santamaría, L; Santiago-Prieto, I; Santostasi, G; Sassolas, B; Sathyaprakash, B S; Sato, S; Satterthwaite, M; Saulson, P R; Savage, R L; Schilling, R; Schlamminger, S; Schnabel, R; Schofield, R M S; Schulz, B; Schutz, B F; Schwinberg, P; Scott, J; Scott, S M; Searle, A C; Seifert, F; Sellers, D; Sengupta, A S; Sentenac, D; Sergeev, A; Shaddock, D A; Shaltev, M; Shapiro, B; Shawhan, P; Shoemaker, D H; Sibley, A; Siemens, X; Sigg, D; Singer, A; Singer, L; Sintes, A M; Skelton, G; Slagmolen, B J J; Slutsky, J; Smith, J R; Smith, M R; Smith, N D; Smith, R J E; Somiya, K; Sorazu, B; Soto, J; Speirits, F C; Sperandio, L; Stefszky, M; Stein, A J; Steinert, E; Steinlechner, J; Steinlechner, S; Steplewski, S; Stochino, A; Stone, R; Strain, K A; Strigin, S; Stroeer, A S; Sturani, R; Stuver, A L; Summerscales, T Z; Sung, M; Susmithan, S; Sutton, P J; Swinkels, B; Tacca, M; Taffarello, L; Talukder, D; Tanner, D B; Tarabrin, S P; Taylor, J R; Taylor, R; Thomas, P; Thorne, K A; Thorne, K S; Thrane, E; Thüring, A; Titsler, C; Tokmakov, K V; Toncelli, A; Tonelli, M; Torre, O; Torres, C; Torrie, C I; Tournefier, E; Travasso, F; Traylor, G; Trias, M; Tseng, K; Turner, L; Ugolini, D; Urbanek, K; Vahlbruch, H; Vajente, G; Vallisneri, M; Brand, J F J van den; Broeck, C Van Den; van der Putten, S; van Veggel, A A; Vass, S; Vasuth, M; Vaulin, R; Vavoulidis, M; Vecchio, A; Vedovato, G; Veitch, J; Veitch, P J; Veltkamp, C; Verkindt, D; Vetrano, F; Viceré, A; Villar, A E; Vinet, J -Y; Vitale, S; Vocca, H; Vorvick, C; Vyatchanin, S P; Wade, A; Waldman, S J; Wallace, L; Wan, Y; Wang, X; Wang, Z; Wanner, A; Ward, R L; Was, M; Wei, P; Weinert, M; We, A J; Weiss, R; Wen, L; Wen, S; Wessels, P; West, M; Westphal, T; Wette, K; Whelan, J T; Whitcomb, S E; White, D; Whiting, B F; Wilkinson, C; Willems, P A; Williams, H R; Williams, L; Willke, B; Winkelmann, L; Winkler, W; Wipf, C C; Wiseman, A G; Wittel, H; Woan, G; Wooley, R; Worden, J; Yablon, J; Yakushin, I; Yamamoto, H; Yamamoto, K; Yang, H; Yeaton-Massey, D; Yoshida, S; Yu, P; Yvert, M; Zadroźny, A; Zanolin, M; Zendri, J -P; Zhang, F; Zhang, L; Zhang, W; Zhang, Z; Zhao, C; Zotov, N; Zucker, M E; Zweizig, J; Boer, M; Fender, R; Gehrels, N; Klotz, A; Ofek, E O; Smith, M; Sokolowski, M; Stappers, B W; Steele, I; Swinbank, J; Wijers, R A M J

    2011-01-01

    Aims. A transient astrophysical event observed in both gravitational wave (GW) and electromagnetic (EM) channels would yield rich scientific rewards. A first program initiating EM follow-ups to possible transient GW events has been developed and exercised by the LIGO and Virgo community in association with several partners. In this paper, we describe and evaluate the methods used to promptly identify and localize GW event candidates and to request images of targeted sky locations. Methods. During two observing periods (Dec 17 2009 to Jan 8 2010 and Sep 2 to Oct 20 2010), a low-latency analysis pipeline was used to identify GW event candidates and to reconstruct maps of possible sky locations. A catalog of nearby galaxies and Milky Way globular clusters was used to select the most promising sky positions to be imaged, and this directional information was delivered to EM observatories with time lags of about thirty minutes. A Monte Carlo simulation has been used to evaluate the low-latency GW pipeline's ability...

  17. Searching for the optical counterparts of two young gamma-ray pulsars

    CERN Document Server

    Mignani, R P; Marelli, M; De Luca, A; Pierbattista, M; Razzano, M; Salvetti, D; Belfiore, A; Shearer, A; Moran, P

    2016-01-01

    We report on the first deep optical observations of two $\\gamma$-ray pulsars, both among the very first discovered by the {\\em Fermi} Gamma-ray Space Telescope. The two pulsars are the radio-loud PSR\\, J1907+0602 in the TeV pulsar wind nebula (PWN) MGRO\\, J1908+06 and the radio-quiet PSR\\, J1809$-$2332 in the "Taz" radio/X-ray PWN. They are relatively young, with spin-down ages of 19.5 and 67.6 kyr, respectively and energetic, with spin-down energies $\\dot{E}_{\\rm rot} = 2.8 \\times 10^{36}$ erg s$^{-1}$ (PSR\\, J1907+0602) and $\\dot{E}_{\\rm rot} = 4.3 \\times 10^{35}$ erg s$^{-1}$ (PSR\\, J1809$-$2332). Both pulsars have been detected in the X-rays by \\xmm, which makes them viable targets for optical observations. We observed the pulsar fields in the B and V bands with the Very Large Telescope (VLT) in June/July 2015. Neither of the two pulsars has been detected down to $3\\sigma$ limiting magnitudes of $m_{\\rm v} \\sim 26.9$ and $m_{\\rm v} \\sim 27.6$ for PSR\\, J1907+0602 and PSR\\, J1809$-$2332, respectively. We d...

  18. Implementation and testing of the first prompt search for gravitational wave transients with electromagnetic counterparts

    Science.gov (United States)

    LIGO Scientific Collaboration; Virgo Collaboration; Abadie, J.; Abbott, B. P.; Abbott, R.; Abbott, T. D.; Abernathy, M.; Accadia, T.; Acernese, F.; Adams, C.; Adhikari, R.; Affeldt, C.; Ajith, P.; Allen, B.; Allen, G. S.; Amador Ceron, E.; Amariutei, D.; Amin, R. S.; Anderson, S. B.; Anderson, W. G.; Arai, K.; Arain, M. A.; Araya, M. C.; Aston, S. M.; Astone, P.; Atkinson, D.; Aufmuth, P.; Aulbert, C.; Aylott, B. E.; Babak, S.; Baker, P.; Ballardin, G.; Ballmer, S.; Barker, D.; Barone, F.; Barr, B.; Barriga, P.; Barsotti, L.; Barsuglia, M.; Barton, M. A.; Bartos, I.; Bassiri, R.; Bastarrika, M.; Basti, A.; Batch, J.; Bauchrowitz, J.; Bauer, Th. S.; Bebronne, M.; Behnke, B.; Beker, M. G.; Bell, A. S.; Belletoile, A.; Belopolski, I.; Benacquista, M.; Berliner, J. M.; Bertolini, A.; Betzwieser, J.; Beveridge, N.; Beyersdorf, P. T.; Bilenko, I. A.; Billingsley, G.; Birch, J.; Biswas, R.; Bitossi, M.; Bizouard, M. A.; Black, E.; Blackburn, J. K.; Blackburn, L.; Blair, D.; Bland, B.; Blom, M.; Bock, O.; Bodiya, T. P.; Bogan, C.; Bondarescu, R.; Bondu, F.; Bonelli, L.; Bonnand, R.; Bork, R.; Born, M.; Boschi, V.; Bose, S.; Bosi, L.; Bouhou, B.; Braccini, S.; Bradaschia, C.; Brady, P. R.; Braginsky, V. B.; Branchesi, M.; Brau, J. E.; Breyer, J.; Briant, T.; Bridges, D. O.; Brillet, A.; Brinkmann, M.; Brisson, V.; Britzger, M.; Brooks, A. F.; Brown, D. A.; Brummit, A.; Bulik, T.; Bulten, H. J.; Buonanno, A.; Burguet-Castell, J.; Burmeister, O.; Buskulic, D.; Buy, C.; Byer, R. L.; Cadonati, L.; Cagnoli, G.; Calloni, E.; Camp, J. B.; Campsie, P.; Cannizzo, J.; Cannon, K.; Canuel, B.; Cao, J.; Capano, C. D.; Carbognani, F.; Caride, S.; Caudill, S.; Cavaglià, M.; Cavalier, F.; Cavalieri, R.; Cella, G.; Cepeda, C.; Cesarin, E.; Chaibi, O.; Chalermsongsak, T.; Chalkley, E.; Charlton, P.; Chassande-Mottin, E.; Chelkowski, S.; Chen, Y.; Chincarini, A.; Chiummo, A.; Cho, H.; Christensen, N.; Chua, S. S. Y.; Chung, C. T. Y.; Chung, S.; Ciani, G.; Clara, F.; Clark, D. E.; Clark, J.; Clayton, J. H.; Cleva, F.; Coccia, E.; Cohadon, P.-F.; Colacino, C. N.; Colas, J.; Colla, A.; Colombini, M.; Conte, A.; Conte, R.; Cook, D.; Corbitt, T. R.; Cordier, M.; Cornish, N.; Corsi, A.; Costa, C. A.; Coughlin, M.; Coulon, J.-P.; Couvares, P.; Coward, D. M.; Coyne, D. C.; Creighton, J. D. E.; Creighton, T. D.; Cruise, A. M.; Cumming, A.; Cunningham, L.; Cuoco, E.; Cutler, R. M.; Dahl, K.; Danilishin, S. L.; Dannenberg, R.; D'Antonio, S.; Danzmann, K.; Dattilo, V.; Daudert, B.; Daveloza, H.; Davier, M.; Davies, G.; Daw, E. J.; Day, R.; Dayanga, T.; DeRosa, R.; Debra, D.; Debreczeni, G.; Degallaix, J.; Del Pozzo, W.; Del Prete, M.; Dent, T.; Dergachev, V.; Derosa, R.; Desalvo, R.; Dhillon, V.; Dhurandhar, S.; Di Fiore, L.; Di Lieto, A.; Di Palma, I.; De Paolo Emilio, M.; Di Virgilio, A.; Díaz, M.; Dietz, A.; Diguglielmo, J.; Donovan, F.; Dooley, K. L.; Dorsher, S.; Drago, M.; Drever, R. W. P.; Driggers, J. C.; Du, Z.; Dumas, J.-C.; Dwyer, S.; Eberle, T.; Edgar, M.; Edwards, M.; Effler, A.; Ehrens, P.; Endröczi, G.; Engel, R.; Etzel, T.; Evans, K.; Evans, M.; Evans, T.; Factourovich, M.; Fafone, V.; Fairhurst, S.; Fan, Y.; Farr, B. F.; Farr, W.; Fazi, D.; Fehrmann, H.; Feldbaum, D.; Ferrante, I.; Fidecaro, F.; Finn, L. S.; Fiori, I.; Fisher, R. P.; Flaminio, R.; Flanigan, M.; Foley, S.; Forsi, E.; Forte, L. A.; Fotopoulos, N.; Fournier, J.-D.; Franc, J.; Frasca, S.; Frasconi, F.; Frede, M.; Frei, M.; Frei, Z.; Freise, A.; Frey, R.; Fricke, T. T.; Fridriksson, J. K.; Friedrich, D.; Fritschel, P.; Frolov, V. V.; Fulda, P. J.; Fyffe, M.; Galimberti, M.; Gammaitoni, L.; Ganija, M. R.; Garcia, J.; Garofoli, J. A.; Garufi, F.; Gáspár, M. E.; Gemme, G.; Geng, R.; Genin, E.; Gennai, A.; Gergely, L. Á.; Ghosh, S.; Giaime, J. A.; Giampanis, S.; Giardina, K. D.; Giazotto, A.; Gill, C.; Goetz, E.; Goggin, L. M.; González, G.; Gorodetsky, M. L.; Goßler, S.; Gouaty, R.; Graef, C.; Granata, M.; Grant, A.; Gras, S.; Gray, C.; Gray, N.; Greenhalgh, R. J. S.; Gretarsson, A. M.; Greverie, C.; Grosso, R.; Grote, H.; Grunewald, S.; Guidi, G. M.; Guido, C.; Gupta, R.; Gustafson, E. K.; Gustafson, R.; Ha, T.; Hage, B.; Hallam, J. M.; Hammer, D.; Hammond, G.; Hanks, J.; Hanna, C.; Hanson, J.; Harms, J.; Harry, G. M.; Harry, I. W.; Harstad, E. D.; Hartman, M. T.; Haughian, K.; Hayama, K.; Hayau, J.-F.; Hayler, T.; Heefner, J.; Heidmann, A.; Heintze, M. C.; Heitmann, H.; Hello, P.; Hendry, M. A.; Heng, I. S.; Heptonstall, A. W.; Herrera, V.; Hewitson, M.; Hild, S.; Hoak, D.; Hodge, K. A.; Holt, K.; Homan, J.; Hong, T.; Hooper, S.; Hosken, D. J.; Hough, J.; Howell, E. J.; Hughey, B.; Husa, S.; Huttner, S. H.; Huynh-Dinh, T.; Ingram, D. R.; Inta, R.; Isogai, T.; Ivanov, A.; Izumi, K.; Jacobson, M.; Jang, H.; Jaranowski, P.; Johnson, W. W.; Jones, D. I.; Jones, G.; Jones, R.

    2012-04-01

    Aims: A transient astrophysical event observed in both gravitational wave (GW) and electromagnetic (EM) channels would yield rich scientific rewards. A first program initiating EM follow-ups to possible transient GW events has been developed and exercised by the LIGO and Virgo community in association with several partners. In this paper, we describe and evaluate the methods used to promptly identify and localize GW event candidates and to request images of targeted sky locations. Methods: During two observing periods (Dec. 17, 2009 to Jan. 8, 2010 and Sep. 2 to Oct. 20, 2010), a low-latency analysis pipeline was used to identify GW event candidates and to reconstruct maps of possible sky locations. A catalog of nearby galaxies and Milky Way globular clusters was used to select the most promising sky positions to be imaged, and this directional information was delivered to EM observatories with time lags of about thirty minutes. A Monte Carlo simulation has been used to evaluate the low-latency GW pipeline's ability to reconstruct source positions correctly. Results: For signals near the detection threshold, our low-latency algorithms often localized simulated GW burst signals to tens of square degrees, while neutron star/neutron star inspirals and neutron star/black hole inspirals were localized to a few hundred square degrees. Localization precision improves for moderately stronger signals. The correct sky location of signals well above threshold and originating from nearby galaxies may be observed with ~50% or better probability with a few pointings of wide-field telescopes.

  19. UNVEILING THE NATURE OF THE UNIDENTIFIED GAMMA-RAY SOURCES. IV. THE SWIFT CATALOG OF POTENTIAL X-RAY COUNTERPARTS

    Energy Technology Data Exchange (ETDEWEB)

    Paggi, A.; D' Abrusco, R.; Smith, H. A. [Harvard-Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Massaro, F.; Funk, S. [SLAC National Laboratory and Kavli Institute for Particle Astrophysics and Cosmology, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Masetti, N. [INAF-Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna, via Gobetti 101, I-40129 Bologna (Italy); Giroletti, M. [INAF Istituto di Radioastronomia, via Gobetti 101, I-40129 Bologna (Italy); Tosti, G., E-mail: apaggi@cfa.harvard.edu [Dipartimento di Fisica, Università degli Studi di Perugia, I-06123 Perugia (Italy)

    2013-11-01

    A significant fraction (∼30%) of the high-energy γ-ray sources listed in the second Fermi Large Area Telescope (LAT) catalog are still of unknown origin, having not yet been associated with counterparts at lower energies. To investigate the nature of these enigmatic sources, we present an extensive search of X-ray sources lying in the positional uncertainty region of a selected sample of these unidentified gamma-ray sources (UGSs) that makes use of all available observations performed by the Swift X-ray Telescope before 2013 March 31, available for 205 UGSs. To detect the fainter sources, we merged all the observations covering the Fermi LAT positional uncertainty region at a 95% level of confidence of each UGS. This yields a catalog of 357 X-ray sources, finding candidate X-ray counterparts for ∼70% of the selected sample. In particular, 25% of the UGSs feature a single X-ray source within their positional uncertainty region, while 45% have multiple X-ray sources. For each X-ray source, we also looked in the corresponding Swift UVOT merged images for optical and ultraviolet counterparts, also performing source photometry. We found ultraviolet-optical correspondences for ∼70% of the X-ray sources. We searched several major radio, infrared, optical, and ultraviolet surveys for possible counterparts within the positional error of the sources in the X-ray catalog to obtain additional information on their nature. Applying the kernel density estimation technique to infrared colors of Wide-Field Infrared Survey Explorer counterparts of our X-ray sources we select six γ-ray blazar candidates. In addition, comparing our results with previous analyses, we select 11 additional γ-ray blazar candidates.

  20. The effects of goal orientation on job search and reemployment: a field experiment among unemployed job seekers.

    Science.gov (United States)

    van Hooft, Edwin A J; Noordzij, Gera

    2009-11-01

    Because unemployment has detrimental effects on the well-being of unemployed people, it is important that unemployed individuals move back to work. The present study aimed at improving the understanding of the job search and reemployment process by applying goal orientation theory to job seeking. Using a 3-group field experimental design among 109 unemployed job seekers, the authors examined the effects of situational learning and performance goal orientation on participants' job search intentions, job search behavior, and reemployment status. A situational focus on learning goals was found to be beneficial for the job search process, leading to more search intentions, more search behavior, and higher reemployment probabilities. These effects seemed to be independent of people's dispositional goal orientation. Findings indicate that goal orientation is a promising construct for both science and practice in the field of job seeking.

  1. Kinematic tau reconstruction and search for the Higgs boson in hadronic tau pair decays with the CMS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Perchalla, Lars

    2011-05-11

    The thesis prepares a search for the Standard Model Higgs boson in the di-tau channel with the CMS experiment. Based on Monte Carlo simulations, two selections are developed for light Higgs bosons produced by the dominant processes, gluon fusion and vector-boson fusion. Both selections exclusively consider the hadronic tau decay into three charged pions. They rely on an efficient algorithm to identify the tau decay products within the hadronic environment at the LHC. A kinematic fit exploits the topology of the particular decay mode and enables the reconstruction of the entire tau momentum including the neutrino. A set of quality criteria is defined on the obtained observables, which is valid for a broad range of tau energies. This provides an efficient suppression of quark and gluon jets that fake tau decays. The Higgs boson is reconstructed from pairs of tau leptons that pass the quality requirements. The selections derive further background suppression from the event kinematics. In case of the gluon fusion, the selected sample is dominated by off-shell Z{sup 0} bosons that decay into tau pairs. The vector-boson fusion involves two additional quark jets. Their signature and the significant transversal momentum of the Higgs boson allow for a background-free selection. The significance of both selections is discussed for an integrated luminosity of 30 fb{sup -1}. (orig.)

  2. The QUAX-g_p g_s experiment to search for monopole-dipole Axion interaction

    CERN Document Server

    Crescini, Nicolò; Carugno, Giovanni; Falferi, Paolo; Ortolan, Antonello; Ruoso, Giuseppe

    2016-01-01

    The QCD axion is an hypothetical particle introduced to solve the strong CP problem of standard model of particle physics and is of interest as a possible component of cold dark matter. In the axion scenario, J.E. Moody and F. Wilczek showed that a new macroscopic long-range force, mediated by axion exchange, acts on electron spins, and that such force can be described in terms of an effective magnetic field. The QUAX-g$_p$g$_s$ experiment, carried out at INFN Laboratori Nazionali di Legnaro, is designed to search for the effects on magnetized samples of the effective field produced by unpolarized mass sources. As this field is macroscopic, it can be detected by measuring the change of magnetization of a paramagnetic Gadolinium silicate (GSO) crystal cooled at liquid helium temperature. The axion effective field induced magnetization can be detected with a SQUID magnetometer. By varying the position of the of source masses, the induced GSO magnetization is modulated at acoustic frequencies. Although the full ...

  3. Search for electroweakly produced supersymmetric particles in final states including two charged leptons with the ATLAS experiment at the LHC

    CERN Document Server

    Wittkowski, Josephine

    Three analyses searching for electroweakly produced supersymmetric particles in proton-proton collisions are presented. The collisions were recorded by the ATLAS experiment at the Large Hadron Collider. Two leptons (electrons or muons), jets and missing transverse energy are expected in the final states. Simplified models as well as the phenomenological Minimal Supersymmetric Standard Model (pMSSM) are used to study the production and decay of pairs of gauginos, i.e. charginos and neutralinos. The first analysis is performed with an integrated luminosity of 4.7 fb^-1 of ATLAS data, recorded in 2011 at a centre-of-mass energy of sqrt(s) = 7 TeV. Direct slepton production and three scenarios in which pairs of gauginos decay via intermediate sleptons are addressed. Particular attention is paid to the trigger strategy. No excess is observed in the number of data events. In the simplified model that assumes the direct slepton production, left-handed slepton masses between 85 and 195 GeV are excluded at 95% confide...

  4. Search for $VH\\rightarrow$ leptons + $b\\bar{b}$ with the ATLAS experiment at the LHC

    CERN Document Server

    AUTHOR|(CDS)2079589

    The search for a Higgs boson decaying to a $b\\bar{b}$ pair is one of the key analyses ongoing at the ATLAS experiment. Despite being the largest branching ratio decay for a Standard Model Higgs boson, a large dataset is necessary to perform this analysis because of the very large backgrounds affecting the measurement. To discriminate the electroweak $H\\rightarrow b\\bar{b}$ signal from the large QCD backgrounds, the associated production of the Higgs with a $W$ or a $Z$ boson decaying leptonically is used. Different techniques have been proposed to enhance the signal over background ratio in the $VH(b\\bar{b})$ channel, from dedicated kinematic cuts, to a single large radius jet to identify the two collimated $b$'s in the Higgs high transverse momentum regime, to multivariate techniques. The high-$p_{\\mathrm{T}}$ approach, using a large radius jet to identify the $b$'s coming from the Higgs decay, has been tested against an analysis based on kinematic cuts for a dataset of $4.7$ fb$^{-1}$ luminosity at $\\sqrt{s...

  5. Tau lepton reconstruction with energy flow and the search for R-parity violating supersymmetry at the ATLAS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Fleischmann, Sebastian

    2012-10-15

    This thesis investigates the discovery potential of the ATLAS experiment at the Large Hadron Collider (LHC) for R-parity violating (RPV) supersymmetric (SUSY) models in the framework of mSUGRA, where the stau ({tau}) is the lightest supersymmetric particle (LSP). Hence, the LSP is charged and decays in contrast to R-parity conserving models. For the first time in the framework of this RPV model a detailed signal to background analysis is performed for a specific benchmark scenario using a full Monte Carlo simulation of the ATLAS detector. Furthermore a feasibility study for an estimate of the stau LSP mass is given. The fast track simulation FATRAS is a new approach for the Monte Carlo simulation of particles in the tracking systems of the ATLAS experiment. Its results are compared to first data at {radical}(s) = 900 GeV. Additionally, two generic detector simulations are compared to the full simulation. The reconstruction of tau leptons is crucial for many searches for new physics with ATLAS. Therefore, the reconstruction of tracks for particles from tau decays is studied. A novel method, PanTau, is presented for the tau reconstruction in ATLAS. It is based on the energy flow algorithm eflowRec. Its performance is evaluated in Monte Carlo simulations. The dependency of the identification variables on the jet energy are studied in detail. Finally, the energy flow quantities and the identification variables are compared between Monte Carlo simulations and measured multijet events with first ATLAS data at {radical}(s) = 7 TeV.

  6. Students' Scientific Epistemic Beliefs, Online Evaluative Standards, and Online Searching Strategies for Science Information: The Moderating Role of Cognitive Load Experience

    Science.gov (United States)

    Hsieh, Ya-Hui; Tsai, Chin-Chung

    2014-01-01

    The purpose of this study is to examine the moderating role of cognitive load experience between students' scientific epistemic beliefs and information commitments, which refer to online evaluative standards and online searching strategies. A total of 344 science-related major students participated in this study. Three questionnaires were…

  7. Radio Counterparts of Compact Binary Mergers Detectable in Gravitational Waves: A Simulation for an Optimized Survey

    Science.gov (United States)

    Hotokezaka, K.; Nissanke, S.; Hallinan, G.; Lazio, T. J. W.; Nakar, E.; Piran, T.

    2016-11-01

    Mergers of binary neutron stars and black hole-neutron star binaries produce gravitational-wave (GW) emission and outflows with significant kinetic energies. These outflows result in radio emissions through synchrotron radiation. We explore the detectability of these synchrotron-generated radio signals by follow-up observations of GW merger events lacking a detection of electromagnetic counterparts in other wavelengths. We model radio light curves arising from (i) sub-relativistic merger ejecta and (ii) ultra-relativistic jets. The former produce radio remnants on timescales of a few years and the latter produce γ-ray bursts in the direction of the jet and orphan-radio afterglows extending over wider angles on timescales of weeks. Based on the derived light curves, we suggest an optimized survey at 1.4 GHz with five epochs separated by a logarithmic time interval. We estimate the detectability of the radio counterparts of simulated GW-merger events to be detected by advanced LIGO and Virgo by current and future radio facilities. The detectable distances for these GW merger events could be as high as 1 Gpc. Around 20%-60% of the long-lasting radio remnants will be detectable in the case of the moderate kinetic energy of 3\\cdot {10}50 erg and a circum-merger density of 0.1 {{cm}}-3 or larger, while 5%-20% of the orphan-radio afterglows with kinetic energy of 1048 erg will be detectable. The detection likelihood increases if one focuses on the well-localizable GW events. We discuss the background noise due to radio fluxes of host galaxies and false positives arising from extragalactic radio transients and variable active galactic nuclei, and we show that the quiet radio transient sky is of great advantage when searching for the radio counterparts.

  8. Improved Scatter Search Using Cuckoo Search

    Directory of Open Access Journals (Sweden)

    Ahmed T.Sadiq Al-Obaidi

    2013-02-01

    Full Text Available The Scatter Search (SS is a deterministic strategy that has been applied successfully to some combinatorial and continuous optimization problems. Cuckoo Search (CS is heuristic search algorithm which is inspired by the reproduction strategy of cuckoos. This paper presents enhanced scatter search algorithm using CS algorithm. The improvement provides Scatter Search with random exploration for search space of problem and more of diversity and intensification for promising solutions. The original and improved Scatter Search has been tested on Traveling Salesman Problem. A computational experiment with benchmark instances is reported. The results demonstrate that the improved Scatter Search algorithms produce better performance than original Scatter Search algorithm. The improvement in the value of average fitness is 23.2% comparing with original SS. The developed algorithm has been compared with other algorithms for the same problem, and the result was competitive with some algorithm and insufficient with another.

  9. Search for $\

    OpenAIRE

    Astier, P.; Autiero, D.; Baldisseri, A.; Baldo-Ceolin, M.; Banner, M.; Bassompierre, G.; Benslama, K.; Besson, N.; Bird, I.; Blumenfeld, B.; Bobisut, F.; J. Bouchez; Boyd, S.; A. Bueno; Bunyatov, S.

    2003-01-01

    Neutrinos; We present the results of a search for nu_mu → nu_e oscillations in the NOMAD experiment at Cern. The experiment looked for the appearance of nu_e in a predominantly nu_mu wide-band neutrino beam at the CERN SPS. No evidence for oscillations was found. The 90% confidence limits obtained are Delta m^2 ~ 10 eV^2.

  10. Search for $\

    CERN Document Server

    Astier, Pierre; Baldisseri, Alberto; Baldo-Ceolin, Massimilla; Banner, M; Bassompierre, Gabriel; Benslama, K; Besson, N; Bird, I; Blumenfeld, B; Bobisut, F; Bouchez, J; Boyd, S; Bueno, A G; Bunyatov, S A; Camilleri, L L; Cardini, A; Cattaneo, Paolo Walter; Cavasinni, V; Cervera-Villanueva, A; Challis, R C; Chukanov, A; Collazuol, G; Conforto, G; Conta, C; Contalbrigo, M; Cousins, R D; Daniels, D; De Santo, A; Degaudenzi, H M; Del Prete, T; Di Lella, L; Dignan, T; Dumarchez, J; Feldman, G J; Ferrari, A; Ferrari, R; Ferrère, D; Flaminio, Vincenzo; Fraternali, M; Gaillard, J M; Gangler, E; Geiser, A; Geppert, D; Gibin, D; Gninenko, S N; Godley, A; Gosset, J; Gouanère, M; Grant, A; Graziani, G; Guglielmi, A M; Gómez-Cadenas, J J; Gössling, C; Hagner, C; Hernando, J; Hong, T M; Hubbard, D B; Hurst, P; Hyett, N; Iacopini, E; Joseph, C L; Juget, F R; Kent, N; Kirsanov, M M; Klimov, O; Kokkonen, J; Kovzelev, A; Krasnoperov, A V; Kustov, D; La Rotonda, L; Lacaprara, S; Lachaud, C; Lakic, B; Lanza, A; Laveder, M; Letessier-Selvon, A A; Linssen, Lucie; Ljubicic, A; Long, J; Lupi, A; Lévy, J M; Marchionni, A; Martelli, F; Mendiburu, J P; Meyer, J P; Mezzetto, Mauro; Mishra, S R; Moorhead, G F; Méchain, X; Naumov, D V; Nefedov, Yu A; Nguyen-Mau, C; Nédélec, P; Orestano, D; Pastore, F; Peak, L S; Pennacchio, E; Pessard, H; Petti, R; Placci, A; Polesello, G; Pollmann, D; Polyarush, A Yu; Popov, B; Poulsen, C; Rebuffi, L; Renò, R; Rico, J; Riemann, P; Roda, C; Rubbia, André; Salvatore, F; Schahmaneche, K; Schmidt, B; Schmidt, T; Sconza, A; Sevior, M E; Shih, D; Sillou, D; Soler, F J P; Sozzi, G; Steele, D; Stiegler, U; Stipcevic, M; Stolarczyk, T; Tareb-Reyes, M; Taylor, G N; Tereshchenko, V V; Toropin, A N; Touchard, A M; Tovey, Stuart N; Tran, M T; Tsesmelis, E; Ulrichs, J; Vacavant, L; Valdata-Nappi, M; Valuev, V Yu; Vannucci, François; Varvell, K E; Veltri, M; Vercesi, V; Vidal-Sitjes, G; Vieira, J M; Vinogradova, T G; Weber, F V; Weisse, T; Wilson, F F; Winton, L J; Yabsley, B D; Zaccone, Henri; Zuber, K; Zuccon, P; do Couto e Silva, E

    2003-01-01

    We present the results of a search for nu_mu → nu_e oscillations in the NOMAD experiment at Cern. The experiment looked for the appearance of nu_e in a predominantly nu_mu wide-band neutrino beam at the CERN SPS. No evidence for oscillations was found. The 90% confidence limits obtained are Delta m^2 ~ 10 eV^2.

  11. Search for $\

    CERN Document Server

    Astier, Pierre; Baldisseri, Alberto; Baldo-Ceolin, Massimilla; Banner, M; Bassompierre, Gabriel; Benslama, K; Besson, N; Bird, I; Blumenfeld, B; Bobisut, F; Bouchez, J; Boyd, S; Bueno, A G; Bunyatov, S; Camilleri, L L; Cardini, A; Cattaneo, Paolo Walter; Cavasinni, V; Cervera-Villanueva, A; Challis, R C; Chukanov, A; Collazuol, G; Conforto, G; Conta, C; Contalbrigo, M; Cousins, R; Daniels, D; Degaudenzi, H M; Del Prete, T; De Santo, A; Dignan, T; Di Lella, L; do Couto e Silva, E; Dumarchez, J; Ellis, M; Feldman, G J; Ferrari, R; Ferrère, D; Flaminio, Vincenzo; Fraternali, M; Gaillard, J M; Gangler, E; Geiser, A; Geppert, D; Gibin, D; Gninenko, S N; Godley, A; Gómez-Cadenas, J J; Gosset, J; Gössling, C; Gouanère, M; Grant, A; Graziani, G; Guglielmi, A M; Hagner, C; Hernando, J A; Hubbard, D B; Hurst, P; Hyett, N; Iacopini, E; Joseph, C L; Juget, F R; Kent, N; Kirsanov, M M; Klimov, O; Kokkonen, J; Kovzelev, A; Krasnoperov, A V; Kustov, D; Lacaprara, S; Lachaud, C; Lakic, B; Lanza, A; La Rotonda, L; Laveder, M; Letessier-Selvon, A A; Lévy, J M; Linssen, Lucie; Ljubicic, A; Long, J; Lupi, A; Marchionni, A; Martelli, F; Méchain, X; Mendiburu, J P; Meyer, J P; Mezzetto, Mauro; Mishra, S R; Moorhead, G F; Naumov, D V; Nédélec, P; Nefedov, Yu A; Nguyen-Mau, C; Orestano, D; Pastore, F; Peak, L S; Pennacchio, E; Pessard, H; Petti, R; Placci, A; Polesello, G; Pollmann, D; Polyarush, A Yu; Popov, B; Poulsen, C; Rebuffi, L; Renò, R; Rico, J; Riemann, P; Roda, C; Rubbia, André; Salvatore, F; Schahmaneche, K; Schmidt, B; Schmidt, T; Sconza, A; Sevior, M E; Sillou, D; Soler, F J P; Sozzi, G; Steele, D; Stiegler, U; Stipcevic, M; Stolarczyk, T; Tareb-Reyes, M; Taylor, G; Tereshchenko, V V; Toropin, A N; Touchard, A M; Tovey, Stuart N; Tran, M T; Tsesmelis, E; Ulrichs, J; Vacavant, L; Valdata-Nappi, M; Valuev, V Y; Vannucci, François; Varvell, K E; Veltri, M; Vercesi, V; Vidal-Sitjes, G; Vieira, J M; Vinogradova, T G; Weber, F V; Weisse, T; Wilson, F F; Winton, L J; Yabsley, B D; Zaccone, Henri; Zuber, K; Zuccon, P

    2001-01-01

    We present the results of a search for nu(mu)-->nu(e) oscillations in the NOMAD experiment at CERN. The experiment looked for the appearance of nu(e) in a predominantly nu(mu) wide-band neutrino beam at the CERN SPS. No evidence for oscillations was found. The 90% confidence limits obtained are delta m^2 10 eV^2.

  12. The {ital COBE} Diffuse Infrared Background Experiment Search for the Cosmic Infrared Background. I. Limits and Detections

    Energy Technology Data Exchange (ETDEWEB)

    Hauser, M.G. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Arendt, R.G. [Raytheon STX, Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Kelsall, T.; Dwek, E. [Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Odegard, N.; Weiland, J.L.; Freudenreich, H.T. [Raytheon STX, Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Reach, W.T. [California Institute of Technology, IPAC/JPL, MS 100-22, Pasadena, CA 91125 (United States); Silverberg, R.F.; Moseley, S.H. [Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Pei, Y.C. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Lubin, P. [Physics Department, University of California at Santa Barbara, Santa Barbara, CA 93106 (United States); Mather, J.C.; Shafer, R.A. [Code 685, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Smoot, G.F. [Lawrence Berkeley Laboratory, Space Sciences Laboratory, Department of Physics, UC Berkeley, CA 94720 (United States); Weiss, R. [Massachusetts Institute of Technology, Room 20F-001, Department of Physics, Cambridge, MA 02139 (United States); Wilkinson, D.T. [Princeton University, Department of Physics, Jadwin Hall, Box 708, Princeton, NJ 08544 (United States); Wright, E.L. [UCLA, Astronomy Department, Los Angeles, CA 90024-1562 (United States)

    1998-11-01

    The Diffuse Infrared Background Experiment (DIRBE) on the Cosmic Background Explorer ({ital COBE}) spacecraft was designed primarily to conduct a systematic search for an isotropic cosmic infrared background (CIB) in 10 photometric bands from 1.25 to 240 {mu}m. The results of that search are presented here. Conservative limits on the CIB are obtained from the minimum observed brightness in all-sky maps at each wavelength, with the faintest limits in the DIRBE spectral range being at 3.5 {mu}m ({nu}{ital I}{sub {nu}} {lt} 64 nW m{sup {minus}2} sr{sup {minus}1}, 95{percent} confidence level) and at 240 {mu}m ({nu}{ital I}{sub {nu}} {lt} 28 nW m{sup {minus}2} sr{sup {minus}1}, 95{percent} confidence level). The bright foregrounds from interplanetary dust scattering and emission, stars, and interstellar dust emission are the principal impediments to the DIRBE measurements of the CIB. These foregrounds have been modeled and removed from the sky maps. Assessment of the random and systematic uncertainties in the residuals and tests for isotropy show that only the 140 and 240 {mu}m data provide candidate detections of the CIB. The residuals and their uncertainties provide CIB upper limits more restrictive than the dark sky limits at wavelengths from 1.25 to 100 {mu}m. No plausible solar system or Galactic source of the observed 140 and 240 {mu}m residuals can be identified, leading to the conclusion that the CIB has been detected at levels of {nu}{ital I}{sub {nu}} = 25 {plus_minus} 7 and 14 {plus_minus} 3 nW m{sup {minus}2} sr{sup {minus}1} at 140 and 240 {mu}m, respectively. The integrated energy from 140 to 240 {mu}m, 10.3 nW m{sup {minus}2} sr{sup {minus}1}, is about twice the integrated optical light from the galaxies in the Hubble Deep Field, suggesting that star formation might have been heavily enshrouded by dust at high redshift. The detections and upper limits reported here provide new constraints on models of the history of energy-releasing processes and dust

  13. Do Lower Calorie or Lower Fat Foods Have More Sodium Than Their Regular Counterparts?

    Science.gov (United States)

    John, Katherine A.; Maalouf, Joyce; B. Barsness, Christina; Yuan, Keming; Cogswell, Mary E.; Gunn, Janelle P.

    2016-01-01

    The objective of this study was to compare the sodium content of a regular food and its lower calorie/fat counterpart. Four food categories, among the top 20 contributing the most sodium to the US diet, met the criteria of having the most matches between regular foods and their lower calorie/fat counterparts. A protocol was used to search websites to create a list of “matches”, a regular and comparable lower calorie/fat food(s) under each brand. Nutrient information was recorded and analyzed for matches. In total, 283 matches were identified across four food categories: savory snacks (N = 44), cheese (N = 105), salad dressings (N = 90), and soups (N = 44). As expected, foods modified from their regular versions had significantly reduced average fat (total fat and saturated fat) and caloric profiles. Mean sodium content among modified salad dressings and cheeses was on average 8%–12% higher, while sodium content did not change with modification of savory snacks. Modified soups had significantly lower mean sodium content than their regular versions (28%–38%). Consumers trying to maintain a healthy diet should consider that sodium content may vary in foods modified to be lower in calories/fat. PMID:27548218

  14. Do Lower Calorie or Lower Fat Foods Have More Sodium Than Their Regular Counterparts?

    Science.gov (United States)

    John, Katherine A; Maalouf, Joyce; B Barsness, Christina; Yuan, Keming; Cogswell, Mary E; Gunn, Janelle P

    2016-01-01

    The objective of this study was to compare the sodium content of a regular food and its lower calorie/fat counterpart. Four food categories, among the top 20 contributing the most sodium to the US diet, met the criteria of having the most matches between regular foods and their lower calorie/fat counterparts. A protocol was used to search websites to create a list of "matches", a regular and comparable lower calorie/fat food(s) under each brand. Nutrient information was recorded and analyzed for matches. In total, 283 matches were identified across four food categories: savory snacks (N = 44), cheese (N = 105), salad dressings (N = 90), and soups (N = 44). As expected, foods modified from their regular versions had significantly reduced average fat (total fat and saturated fat) and caloric profiles. Mean sodium content among modified salad dressings and cheeses was on average 8%-12% higher, while sodium content did not change with modification of savory snacks. Modified soups had significantly lower mean sodium content than their regular versions (28%-38%). Consumers trying to maintain a healthy diet should consider that sodium content may vary in foods modified to be lower in calories/fat.

  15. Do Lower Calorie or Lower Fat Foods Have More Sodium Than Their Regular Counterparts?

    Directory of Open Access Journals (Sweden)

    Katherine A. John

    2016-08-01

    Full Text Available The objective of this study was to compare the sodium content of a regular food and its lower calorie/fat counterpart. Four food categories, among the top 20 contributing the most sodium to the US diet, met the criteria of having the most matches between regular foods and their lower calorie/fat counterparts. A protocol was used to search websites to create a list of “matches”, a regular and comparable lower calorie/fat food(s under each brand. Nutrient information was recorded and analyzed for matches. In total, 283 matches were identified across four food categories: savory snacks (N = 44, cheese (N = 105, salad dressings (N = 90, and soups (N = 44. As expected, foods modified from their regular versions had significantly reduced average fat (total fat and saturated fat and caloric profiles. Mean sodium content among modified salad dressings and cheeses was on average 8%–12% higher, while sodium content did not change with modification of savory snacks. Modified soups had significantly lower mean sodium content than their regular versions (28%–38%. Consumers trying to maintain a healthy diet should consider that sodium content may vary in foods modified to be lower in calories/fat.

  16. Using Exploration and Learning for Medical Records Search: An Experiment in Identifying Cohorts for Comparative Effectiveness Research

    Science.gov (United States)

    2012-11-01

    this case we had no prior theory or knowledge about the collection. Therefore, in the absence of a specific theory to act upon or a known search...S., Wood, R., E., Bandura , A., “Impact of Guided Exploration and Enactive Exploration on Self-Regulatory Mechanisms and Information Acquisition

  17. Compact Optical Counterparts of Ultraluminous X-ray Sources

    CERN Document Server

    Tao, Lian; Grise, Fabien; Kaaret, Philip

    2011-01-01

    Using archival Hubble Space Telescope (HST) imaging data, we report the multiband photometric properties of 13 ultraluminous X-ray sources (ULXs) that have a unique compact optical counterpart. Both magnitude and color variation are detected at time scales of days to years. The optical color, variability, and X-ray to optical flux ratio indicate that the optical emission of most ULXs is dominated by X-ray reprocessing on the disk, similar to that of low mass X-ray binaries. For most sources, the optical spectrum is a power-law, $F_{\

  18. A Search For The Z → b anti-b Process at The D-Zero Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, Amber Helen [Imperial College, London (United Kingdom)

    2006-11-01

    In 2001, the D0 experiment entered a new era. Run II of the Tevatron at the Fermi National Accelerator Laboratory began, and the collider became the highest energy particle accelerator in the world. Accordingly, the D0 detector had already undergone a series of upgrades in order to fully exploit the physics now within reach. These included improvements to the tracking, calorimetry, muon detection and triggering capabilities. In the Standard Model, the Higgs boson is the last piece of the puzzle that remains to be discovered. The Higgs mechanism and consequently the Higgs boson is thought to be the fundamental ingredient by which particles acquire mass, and its existence (or lack of existence) is one of the most pressing issues in particle physics today. As such, one of the main goals of the Run II physics programme at D0 is to search for it. Armed with new accelerator capabilities, D0 will be able to impose tighter constraints on the mass of the Higgs, and perhaps even detect this elusive particle. If the Higgs does exist, it will be extremely difficult to find. One of the main challenges at a hadron-hadron collider is to reduce the large QCD background that masks the relatively tiny Higgs signal. Experimental evidence indicates that the Higgs mass is relatively low, in which case it will decay predominantly to a b$\\bar{b}$ quark-antiquark pair. The daughter products that must be used to reconstruct the parent Higgs are therefore likely to be heavy flavour b-quark jets whose energies must be known as accurately as possible. In the first part of this thesis consideration is given to these jets, in particular to the jet energy resolution and dijet mass resolution that they could offer. One way of investigating the necessary tools for such a Higgs search is to study a very similar decay to that of a low-mass Higgs particle: a Z boson decaying to a b quark and an anti-b-quark. This signal, not previously observed at the Tevatron, offers an ideal testbed in which to

  19. Herschel-ATLAS: VISTA VIKING near-IR counterparts in the Phase 1 GAMA 9h data

    CERN Document Server

    Fleuren, S; Dunne, L; Smith, D J B; Maddox, S J; González-Nuevo, J; Findlay, J; Auld, R; Baes, M; Bond, N A; Bonfield, D G; Bourne, N; Cooray, A; Buttiglione, S; Cava, A; Dariush, A; De Zotti, G; Driver, S P; Dye, S; Eales, S; Fritz, J; Gunawardhana, M L P; Hopwood, R; Ibar, E; Ivison, R J; Jarvis, M J; Kelvin, L; Lapi, A; Liske, J; Michalowski, M J; Negrello, M; Pascale, E; Pohlen, M; Prescott, M; Rigby, E E; Robotham, A; Scott, D; Temi, P; Thompson, M A; Valiante, E; van der Werf, P

    2012-01-01

    We identify near-infrared Ks band counterparts to Herschel-ATLAS sub-mm sources, using a preliminary object catalogue from the VISTA VIKING survey. The sub-mm sources are selected from the H-ATLAS Phase 1 catalogue of the GAMA 9h field, which includes all objects detected at 250, 350 or 500 um with the SPIRE instrument. We apply and discuss a likelihood ratio (LR) method for VIKING candidates within a search radius of 10" of the 22,000 SPIRE sources with a 5 sigma detection at 250 um. We find that 11,294(51%) of the SPIRE sources have a best VIKING counterpart with a reliability $R\\ge 0.8$, and the false identification rate of these is estimated to be 4.2%. We expect to miss ~5% of true VIKING counterparts. There is evidence from Z-J and J-Ks colours that the reliable counterparts to SPIRE galaxies are marginally redder than the field population. We obtain photometric redshifts for ~68% of all (non-stellar) VIKING candidates with a median redshift of 0.405. Comparing to the results of the optical identificati...

  20. HST/ACS IMAGING OF OMEGA CENTAURI: OPTICAL COUNTERPARTS OF CHANDRA X-RAY SOURCES

    Energy Technology Data Exchange (ETDEWEB)

    Cool, Adrienne M.; Arias, Tersi; Brochmann, Michelle; Dorfman, Jason; Gafford, April; White, Vivian [Department of Physics and Astronomy, San Francisco State University, 1600 Holloway Avenue, San Francisco, CA 94132 (United States); Haggard, Daryl [Center for Interdisciplinary Exploration and Research in Astrophysics, Physics and Astronomy Department, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States); Anderson, Jay, E-mail: cool@sfsu.edu, E-mail: dhaggard@northwestern.edu [Space Telescope Science Institute, Baltimore, MD 21218 (United States)

    2013-02-15

    We present results of a search for optical counterparts of X-ray sources in and toward the globular cluster Omega Centauri (NGC 5139) using the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. The ACS data consist of a mosaic of Wide Field Channel images obtained using F625W, F435W, and F658N filters; with nine pointings we cover the central {approx}10' Multiplication-Sign 10' of the cluster and encompass 109 known Chandra sources. We find promising optical counterparts for 59 of the sources, {approx}40 of which are likely to be associated with the cluster. These include 27 candidate cataclysmic variables (CVs), 24 of which are reported here for the first time. Fourteen of the CV candidates are very faint, with absolute magnitudes in the range M {sub 625} =10.4-12.6, making them comparable in brightness to field CVs near the period minimum discovered in the Sloan Digital Sky Survey. Additional optical counterparts include three BY Dra candidates, a possible blue straggler, and a previously reported quiescent low-mass X-ray binary. We also identify 3 foreground stars and 11 probable active galactic nuclei. Finally, we report the discovery of a group of seven stars whose X-ray properties are suggestive of magnetically active binaries, and whose optical counterparts lie on or very near the metal-rich anomalous giant and subgiant branches in {omega} Cen. If the apparent association between these seven stars and the RGB/SGB-a stars is real, then the frequency of X-ray sources in this metal-rich population is enhanced by a factor of at least five relative to the other giant and subgiant populations in the cluster. If these stars are not members of the metal-rich population, then they bring the total number of red stragglers (also known as sub-subgiants) that have been identified in {omega} to Cen 20, the largest number yet known in any globular cluster.

  1. Cat Mammary Tumors: Genetic Models for the Human Counterpart

    Directory of Open Access Journals (Sweden)

    Filomena Adega

    2016-08-01

    Full Text Available The records are not clear, but Man has been sheltering the cat inside his home for over 12,000 years. The close proximity of this companion animal, however, goes beyond sharing the same roof; it extends to the great similarity found at the cellular and molecular levels. Researchers have found a striking resemblance between subtypes of feline mammary tumors and their human counterparts that goes from the genes to the pathways involved in cancer initiation and progression. Spontaneous cat mammary pre-invasive intraepithelial lesions (hyperplasias and neoplasias and malignant lesions seem to share a wide repertoire of molecular features with their human counterparts. In the present review, we tried to compile all the genetics aspects published (i.e., chromosomal alterations, critical cancer genes and their expression regarding cat mammary tumors, which support the cat as a valuable alternative in vitro cell and animal model (i.e., cat mammary cell lines and the spontaneous tumors, respectively, but also to present a critical point of view of some of the issues that really need to be investigated in future research.

  2. Identification of a Likely Radio Counterpart of the Rapid Burster

    CERN Document Server

    Moore, C B; Fox, D W; Guerriero, R A; Lewin, W H G; Fender, R P; Van Paradijs, J

    1999-01-01

    We have identified a likely radio counterpart to the low-mass X-ray binary MXB 1730-335 (the Rapid Burster). The counterpart has shown 8.4 GHz radio on/off behavior correlated with the X-ray on/off behavior as observed by the RXTE/ASM during six VLA observations. The probability of an unrelated, randomly varying background source duplicating this behavior is 1--3% depending on the correlation time scale. The location of the radio source is RA 17h 33m 24.61s; Dec -33d 23' 19.8" (J2000), +/- 0.1". We do not detect 8.4 GHz radio emission coincident with type II (accretion-driven) X-ray bursts. The ratio of radio to X-ray emission during such bursts is constrained to be below the ratio observed during X-ray persistent emission at the 2.9-sigma level. Synchrotron bubble models of the radio emission can provide a reasonable fit to the full data set, collected over several outbursts, assuming that the radio evolution is the same from outburst to outburst, but given the physical constraints the emission is more likel...

  3. Using psychometric data from the stated preference (SP experiments to search explanatory power for appropriateness of congestion charging policy

    Directory of Open Access Journals (Sweden)

    Sofyan M. Saleh

    2016-12-01

    Full Text Available Comprehensive stated preference (SP experiment was conducted in Jakarta (a capital of Indonesia, where proposal for congestion charge (CC has been considered as a way to reduce acute traffic congestion. With the government planning a CC scheme, public support is regarded as a prerequisite for its implementation. Therefore, a framework of structural equation model (SEM is used to search explanatory power for the appropriateness of CC considering unobserved variable (latent variable from psychometric data obtained from SP questionare.  Causal paths among psychological determinants and their strength are measured and analyzed along with proposal acceptability from a psychological perspective. The findings from analysis with a SEM approach shows that a number of psychological determinants provide an explanation for the acceptability of the proposed scheme. The findings from analysis with a SEM approach shows that a number of psychological determinants provide an explanation for the appropriateness of the proposed scheme. Latent variables representing the validity of the CC scheme, such as ACE, APC and REC appear to have a significant explanation. These emerge as psychological determinants contributing a positive correlation with enhancement of appropriateness CC policy. Empirical result further shows that males have positive scores for the latent variables of car dependency (CDC and inhibition freedom of movement (IFM. Furthermore, the variable of annual income, it has a positive correlation with recognition of the effects of CC in mitigating congestion and environmental problems (REC, car dependency (CDC and awareness of the problems of cars in society (APC. This means that respondents with higher incomes are more concerned with the problems manifested by motorization while, on the contrary, the path coefficient between annual income (AI and car dependency (CDC has a value of 0.270. This discloses an automobile dependency. These findings should

  4. Development and Testing of a Literature Search Protocol for Evidence Based Nursing: An Applied Student Learning Experience

    Directory of Open Access Journals (Sweden)

    Andy Hickner

    2011-09-01

    Full Text Available Objective – The study aimed to develop a search protocol and evaluate reviewers' satisfaction with an evidence-based practice (EBP review by embedding a library science student in the process.Methods – The student was embedded in one of four review teams overseen by a professional organization for oncology nurses (ONS. A literature search protocol was developed by the student following discussion and feedback from the review team. Organization staff provided process feedback. Reviewers from both case and control groups completed a questionnaire to assess satisfaction with the literature search phases of the review process. Results – A protocol was developed and refined for use by future review teams. The collaboration and the resulting search protocol were beneficial for both the student and the review team members. The questionnaire results did not yield statistically significant differences regarding satisfaction with the search process between case and control groups. Conclusions – Evidence-based reviewers' satisfaction with the literature searching process depends on multiple factors and it was not clear that embedding an LIS specialist in the review team improved satisfaction with the process. Future research with more respondents may elucidate specific factors that may impact reviewers' assessment.

  5. An optimal method for scheduling observations of large sky error regions for finding optical counterparts to transients

    CERN Document Server

    Rana, Javed; Gadre, Bhooshan; Bhalerao, Varun; Bose, Sukanta

    2016-01-01

    The discovery and subsequent study of optical counterparts to transient sources is crucial for their complete astrophysical understanding. Various gamma ray burst (GRB) detectors, and more notably the ground--based gravitational wave detectors, typically have large uncertainties in the sky positions of detected sources. Searching these large sky regions spanning hundreds of square degrees is a formidable challenge for most ground--based optical telescopes, which can usually image less than tens of square degrees of the sky in a single night. We present algorithms for optimal scheduling of such follow--up observations in order to maximize the probability of imaging the optical counterpart, based on the all--sky probability distribution of the source position. We incorporate realistic observing constraints like the diurnal cycle, telescope pointing limitations, available observing time, and the rising/setting of the target at the observatory location. We use simulations to demonstrate that our proposed algorith...

  6. $A$ searches

    CERN Document Server

    Beacham, James

    The Standard Model of particle physics encompasses three of the four known fundamental forces of nature, and has remarkably withstood all of the experimental tests of its predictions, a fact solidified by the discovery, in 2012, of the Higgs boson. However, it cannot be the complete picture. Many measurements have been made that hint at physics beyond the Standard Model, and the main task of the high- energy experimental physics community is to conduct searches for new physics in as many di↵erent places and regimes as possible. I present three searches for new phenomena in three di↵erent high-energy collider experiments, namely, a search for events with at least three photons in the final state, which is sensitive to an exotic decay of a Higgs boson into four photons via intermediate pseudoscalar particles, a, with ATLAS, at the Large Hadron Collider; a search for a dark photon, also known as an A0 , with APEX, at Thomas Je↵erson National Accelerator Facility; and a search for a Higgs decaying into four...

  7. Electromagnetic Counterparts of Gravitational Wave Sources : Mergers of Compact Objects

    CERN Document Server

    Kamble, Atish

    2016-01-01

    Mergers of compact objects are considered prime sources of gravitational waves (GW) and will soon be targets of GW observatories such as the Advanced-LIGO, VIRGO etc. Finding electromagnetic counterparts of these GW sources will be important to understand their nature. We discuss possible electromagnetic signatures of the mergers. We show that the BH-BH mergers could have luminosities which exceed Eddington luminosity from unity to several orders of magnitude depending on the masses of the merging BHs. As a result these mergers could be explosive, release up to $10^{51}$ erg of energy and shine as radio transients. At any given time we expect about a few such transients in the sky at GHz frequencies which could be detected out to about 300 Mpc. It has also been argued that these radio transients would look alike radio supernovae with comparable detection rates. Multi-band follow up could, however, distinguish between the mergers and supernovae.

  8. X-ray Counterparts of Infrared Faint Radio Sources

    Science.gov (United States)

    Schartel, Norbert

    2011-10-01

    Infrared Faint Radio Sources (IFRS) are radio sources with extremely faint or even absent infrared emission in deep Spitzer Surveys. Models of their spectral energy distributions, the ratios of radio to infrared flux densities and their steep radio spectra strongly suggest that IFRS are AGN at high redshifts (2IFRS, but if confirmed, the increased AGN numbers at these redshifts will account for the unresolved part of the X-ray background. The identification of X-ray counterparts of IFRS is considered to be the smoking gun for this hypothesis. We propose to observe 8 IFRS using 30ks pointed observations. X-ray detections of IFRS with different ratios of radio-to-infrared fluxes, will constrain the class-specific SED.

  9. Altitudinal dependence of meteor radio afterglows measured via optical counterparts

    CERN Document Server

    Obenberger, K S; Dowell, J D; Schinzel, F K; Stovall, K; Sutton, E K; Taylor, G B

    2016-01-01

    Utilizing the all-sky imaging capabilities of the LWA1 radio telescope along with a host of all-sky optical cameras, we have now observed 44 optical meteor counterparts to radio afterglows. Combining these observations we have determined the geographic positions of all 44 afterglows. Comparing the number of radio detections as a function of altitude above sea level to the number of expected bright meteors we find a strong altitudinal dependence characterized by a cutoff below $\\sim$ 90 km, below which no radio emission occurs, despite the fact that many of the observed optical meteors penetrated well below this altitude. This cutoff suggests that wave damping from electron collisions is an important factor for the evolution of radio afterglows, which agrees with the hypothesis that the emission is the result of electron plasma wave emission.

  10. Gravitational Coleman–Weinberg potential and its finite temperature counterpart

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharjee, Srijit [Astroparticle Physics and Cosmology Division, Saha Institute of Nuclear Physics, Kolkata 700064 (India); Discipline of Physics, Indian Institute of Technology Gandhinagar, Ahmedabad, Gujarat 382424 (India); Majumdar, Parthasarathi [Department of Physics, Ramakrishna Mission Vivekananada University, Belur Math, Howrah 711202 (India)

    2014-08-15

    Coleman–Weinberg (CW) phenomena for the case of gravitons minimally coupled to massless scalar field is studied. The one-loop effect completely vanishes if there is no self-interaction term present in the matter sector. The one-loop effective potential is shown to develop an instability in the form of acquiring an imaginary part, which can be traced to the tachyonic pole in the graviton propagator. The finite temperature counterpart of this CW potential is computed to study the behaviour of the potential in the high and low temperature regimes with respect to the typical energy scale of the theory. Finite temperature contribution to the imaginary part of gravitational CW potential exhibits a damped oscillatory behaviour; all thermal effects are damped out as the temperature vanishes, consistent with the zero-temperature result.

  11. Electromagnetic Counterparts to Black Hole Mergers Detected by LIGO

    CERN Document Server

    Loeb, Abraham

    2016-01-01

    Mergers of stellar-mass black holes (BHs), such as GW150914 observed by LIGO, are not expected to have electromagnetic counterparts. However, the Fermi GBM detector identified of a gamma-ray transient 0.4 s after the gravitational wave (GW) signal GW150914 with consistent sky localization. I show that the two signals might be related if the BH binary detected by LIGO originated from two clumps in a dumbbell configuration that formed when the core of a rapidly rotating massive star collapsed. In that case, the BH binary merger was followed by a gamma-ray burst (GRB) from a jet that originated in the accretion flow around the remnant BH. A future detection of a GRB afterglow could be used to determine the redshift and precise localization of the source. A population of standard GW sirens with GRB redshifts would provide a new approach for precise measurements of cosmological distances as a function of redshift.

  12. How do older netcitizens compare with their younger counterparts?

    Science.gov (United States)

    Bucur, A; Renold, C; Henke, M

    1999-01-01

    The Internet is modifying the lives of people around the world. Although many talk about the democratization of knowledge and information, differences remain among users as older netcitizens are under-represented and less involved. We use national and representative U.S. data, the Current Population Survey, to show age-based differences. We complement our analysis with web-based data, the Georgia Tech World Wide Web User Surveys, to show Internet characteristics and trends by age for netcitizens. Results show that older users compose a lower share of Internet users than that of the total U.S. population; however, once they join the ranks of avid Internet users, older netcitizens are similar to their younger counterparts.

  13. Chandra Counterparts of CANDELS GOODS-S Sources

    Science.gov (United States)

    Cappelluti, N.; Comastri, A.; Fontana, A.; Zamorani, G.; Amorin, R.; Castellano, M.; Merlin, E.; Santini, P.; Elbaz, D.; Schreiber, C.; Shu, X.; Wang, T.; Dunlop, J. S.; Bourne, N.; Bruce, V. A.; Buitrago, F.; Michałowski, Michał J.; Derriere, S.; Ferguson, H. C.; Faber, S. M.; Vito, F.

    2016-06-01

    Improving the capabilities of detecting faint X-ray sources is fundamental for increasing the statistics on faint high-z active galactic nuclei (AGNs) and star-forming galaxies (SFGs). We performed a simultaneous maximum likelihood point-spread function fit in the [0.5-2] keV and [2-7] keV energy bands of the 4 Ms Chandra Deep Field South (CDFS) data at the position of the 34,930 CANDELS H-band selected galaxies. For each detected source we provide X-ray photometry and optical counterpart validation. We validated this technique by means of a ray-tracing simulation. We detected a total of 698 X-ray point sources with a likelihood { L }\\gt 4.98 (i.e., >2.7σ). We show that prior knowledge of a deep sample of optical-NIR galaxies leads to a significant increase in the detection of faint (i.e., ˜10-17 cgs in the [0.5-2] keV band) sources with respect to “blind” X-ray detections. By including previous X-ray catalogs, this work increases the tot