WorldWideScience

Sample records for h-alpha equivalent width

  1. H{alpha} EQUIVALENT WIDTHS FROM THE 3D-HST SURVEY: EVOLUTION WITH REDSHIFT AND DEPENDENCE ON STELLAR MASS

    Energy Technology Data Exchange (ETDEWEB)

    Fumagalli, Mattia; Patel, Shannon G.; Franx, Marijn; Labbe, Ivo [Leiden Observatory, Leiden University, P.O. Box 9513, 2300-RA Leiden (Netherlands); Brammer, Gabriel [European Southern Observatory, Alonso de Cordova 3107, Casilla 19001, Vitacura, Santiago (Chile); Van Dokkum, Pieter; Lundgren, Britt; Momcheva, Ivelina; Skelton, Rosalind E.; Whitaker, Katherine E.; Nelson, Erica [Department of Astronomy, Yale University, New Haven, CT 06511 (United States); Da Cunha, Elisabete; Rix, Hans-Walter; Schmidt, Kasper B. [Max Planck Institute for Astronomy (MPIA), Koenigstuhl 17, D-69117 Heidelberg (Germany); Kriek, Mariska [Department of Astronomy, University of California, Berkeley, CA 94720 (United States)

    2012-10-01

    We investigate the evolution of the H{alpha} equivalent width, EW(H{alpha}), with redshift and its dependence on stellar mass, using the first data from the 3D-HST survey, a large spectroscopic Treasury program with the Hubble Space Telescope Wide Field Camera 3. Combining our H{alpha} measurements of 854 galaxies at 0.8 < z < 1.5 with those of ground-based surveys at lower and higher redshift, we can consistently determine the evolution of the EW(H{alpha}) distribution from z = 0 to z = 2.2. We find that at all masses the characteristic EW(H{alpha}) is decreasing toward the present epoch, and that at each redshift the EW(H{alpha}) is lower for high-mass galaxies. We find EW(H{alpha}) {approx}(1 + z){sup 1.8} with little mass dependence. Qualitatively, this measurement is a model-independent confirmation of the evolution of star-forming galaxies with redshift. A quantitative conversion of EW(H{alpha}) to specific star formation rate (sSFR) is model dependent because of differential reddening corrections between the continuum and the Balmer lines. The observed EW(H{alpha}) can be reproduced with the characteristic evolutionary history for galaxies, whose star formation rises with cosmic time to z {approx} 2.5 and then decreases to z = 0. This implies that EW(H{alpha}) rises to 400 A at z = 8. The sSFR evolves faster than EW(H{alpha}), as the mass-to-light ratio also evolves with redshift. We find that the sSFR evolves as (1 + z){sup 3.2}, nearly independent of mass, consistent with previous reddening insensitive estimates. We confirm previous results that the observed slope of the sSFR-z relation is steeper than the one predicted by models, but models and observations agree in finding little mass dependence.

  2. H-alpha Equivalent Width Variations across the Face of a Microlensed K Giant in the Galactic Bulge

    CERN Document Server

    Albrow, M; Beaulieu, J P; Caldwell, J A R; Dominik, M; Greenhill, J; Hill, K; Kane, S; Martin, R; Menzies, J; Pollard, K R; Sackett, P D; Sahu, K C; Vermaak, P; Watson, R; Williams, A; Hauschildt, P H

    2001-01-01

    We present VLT FORS1 spectroscopy that temporally resolves the second caustic crossing of the Bulge K giant stellar source of microlensing event EROS 2000-BLG-5, the first time this has been accomplished for several phases of a caustic transit. The ~1 angstrom H-alpha equivalent width of the source star increases slightly as the center of the star egresses the caustic and then plummets by 30% during the final limb crossing. These changes are not seen in contemporaneous spectra of control stars in the FORS1 slit, but are consistent with expectations from stellar atmosphere models as the caustic differentially magnifies different portions of the stellar face of the target. Observations such as these in a variety of stellar lines are equivalent to atmospheric tomography and are expected to provide a direct test of stellar models.

  3. ARES: Automatic Routine for line Equivalent widths in stellar Spectra

    Science.gov (United States)

    Sousa, Sérgio G.

    2012-05-01

    ARES was developed for the measurement of Equivalent Width of absortion lines in stellar spectra; it can also be used to determine fundamental spectroscopic stellar parameters.The code reads a 1D FITS spectra and fits the requested lines in order to calculate the Equivalent width. The code is written in C++ based on the standard method of determining EWs. It automates the manual procedure that one normally carries out when using interactive routines such as the splot routine implemented in IRAF.

  4. PACCE: Perl Algorithm to Compute Continuum and Equivalent Widths

    CERN Document Server

    Riffel, Rogério

    2011-01-01

    We present Perl Algorithm to Compute continuum and Equivalent Widths (pacce). We describe the methods used in the computations and the requirements for its usage. We compare the measurements made with pacce and "manual" ones made using iraf splot task. These tests show that for SSP models the equivalent widths strengths are very similar (differences <0.2A) for both measurements. In real stellar spectra, the correlation between both values is still very good, but with differences of up to 0.5A. pacce is also able to determine mean continuum and continuum at line center values, which are helpful in stellar population studies. In addition, it is also able to compute the uncertainties in the equivalent widths using photon statistics. The code is made available for the community through the web at http://www.if.ufrgs.br/~riffel/software.html.

  5. Measuring Global Galaxy Metallicities Using Emission Line Equivalent Widths

    CERN Document Server

    Kobulnicky, C; Kobulnicky, Chip; Phillips, Andrew

    2003-01-01

    We develop a prescription for estimating the interstellar medium oxygen abundances of distant star-forming galaxies using the ratio EWR_{23} formed from the equivalent widths of the [O II] 3727, [O III] 4959,5007 and Hbeta nebular emission lines. This EWR_{23} approach essentially identical to the widely-used R_{23} method of Pagel et. al (1979). Using data from three spectroscopic surveys of nearby galaxies, we conclude that the emission line equivalent width ratios are a good substitute for emission line flux ratios in galaxies with active star formation. The RMS dispersion between EWR_{23} and the reddening-corrected R_{23} values is sigma(log(R_{23})) < 0.08 dex. This dispersion is comparable to the emission-line measurement uncertainties for distant galaxies in many spectroscopic galaxy surveys, and is smaller than the uncertainties of sigma(O/H) ~ 0.15 dex inherent in strong-line metallicity calibrations. Because equivalent width ratios are, to first order, insentitive to interstellar reddening, emis...

  6. Predicting dust extinction properties of star-forming galaxies from H-alpha/UV ratio

    CERN Document Server

    Koyama, Yusei; Hayashi, Masao; Shimakawa, Rhythm; Yamamura, Issei; Egusa, Fumi; Oi, Nagisa; Tanaka, Ichi; Tadaki, Ken-ichi; Takita, Satoshi; Makiuti, Sin'itirou

    2015-01-01

    Using star-forming galaxies sample in the nearby Universe (0.02H-alpha-to-FUV flux ratio. We find that the H-alpha dust extinction (A(Ha)) derived with H-alpha/H-beta ratio (Balmer decrement) increases with increasing H-alpha/UV ratio as expected, but there remains a considerable scatter around the relation, which is largely dependent on stellar mass and/or H-alpha equivalent width (EW(Ha)). At fixed H-alpha/UV ratio, galaxies with higher stellar mass (or galaxies with lower EW(Ha)) tend to be more highly obscured by dust. We quantify this trend and establish an empirical calibration for predicting A(Ha) with a combination of H-alpha/UV ratio, stellar mass and EW(Ha), with which we can successfully reduce the systematic uncertainties accompanying the simple H-alpha/UV approach by ~15-30%. The new recipes proposed in this study will provide a conveni...

  7. FUNDPAR: A program for Deriving Fundamental Parameters from Equivalent Widths

    Scientific Electronic Library Online (English)

    C, Saffe.

    2011-04-01

    Full Text Available Implementamos un programa en Fortran que determina parámetros fundamentales de estrellas de tipo solar, a partir de anchos equivalentes del Fe. La solución debe verificar tres condiciones en el método estándar: equilibrio de ionización, equilibrio de excitación e independencia entre abundancias y an [...] chos equivalentes. Calculamos modelos de atmósfera de Kurucz con opacidades NEWODF. Detalles como el parámetro de longitud de mezcla, el sobre impulso convectivo, etc. se calculan con un programa independiente. FUNDPAR calcula las incertezas por dos métodos: el criterio de Gonzalez & Vanture (1998) y utilizando la función ?² . Los resultados derivados con FUNDPAR están de acuerdo con determinaciones previas en la literatura. En particular obtuvimos parámetros fundamentales de 58 estrellas con exoplanetas. El programa está disponible en la red1. Abstract in english We implemented a Fortran code that determines fundamental parameters of solar type stars from a list of Fe line equivalent widths. The solution should verify three conditions in the standard method: ionization equilibrium, excitation equilibrium and independence between metallicity and equivalent wi [...] dths. Solarscaled Kurucz model atmospheres with NEWODF opacities are calculated with an independent program. Parameter files control different details, such as the mixinglength parameter and the overshooting. FUNDPAR derives the uncertainties following two methods: the criterion of Gonzalez & Vanture (1998) and the dispersion using the ?2 function. The code uses the 2009 version of the MOOG program. The results derived with FUNDPAR are in agreement with previous determinations in the literature. The program is freely available from the web1.

  8. A New Code for Automatic Determination of Equivalent Widths: Automatic Routine for Line Equivalent Widths in Stellar Spectra (ARES)

    Science.gov (United States)

    Sousa, Sergio A. Gonçalves; Santos, Nuno Cardoso; Monteiro, M. J. P. F. G.; Israelian, Garik; Mayor, Michel

    2007-08-01

    We present a new automatic code (ARES) for the determination of equivalent widths of absorption lines present in stellar spectra. We also describe its use for the determination of fundamental spectroscopic stellar parameters. The code is written in C++ based on the standard method of determining EWs, and is available for the community. The code automates the manual procedure that the users normally carry out when using interactive routines such as the splot routine implemented in IRAF. We test the code using both simulated and real spectra with different levels of resolution and noise comparing its measurements to the manual ones obtained in the standard way. The results shows a small systematic difference, always bellow 1.5mA. This can be explained by errors in the manual measurements due to subjective continuum determination. The code works better and faster than others tested before. This code will be used to analyze spectra from the HARPS sample to search extrasolar planets.

  9. Observation of an H-alpha outburst in the Be star HR 4123

    International Nuclear Information System (INIS)

    During routine monitoring of the Be star HR 4123 during the year 1987-1988, a burst of H-alpha emission was observed on May 11, 1987. The increase was observed on May 9 and lasted until June 7, peaking to an equivalent width of 31.6 A on May 11. This short-term burst is interpreted as due to the presence of a compact object in binary motion around the Be star, which accretes the matter ejected by the Be star to give out X-rays, which in turn produce ionization in the gas to give out the H-alpha emission. The broad line at 6577.5 A observed to accompany H-alpha emission during the burst is suggested to be emission from dielectronic recombination from C III ions in a C II region around the H II region formed by the X radiation. 18 refs

  10. Balmer line equivalent widths of B-F main sequence stars. Comparison with theoretical models

    International Nuclear Information System (INIS)

    The equivalent widths of the Balmer lines Hsub(?) and Hsub(?) and Hsub(?) were obtained for 175 B-F main-sequence stars. The comparison with the values calculated on the basis of modern stellar atmosphere models is represented. Mean for spectral class values of Wsub(lambda) are shown to be in a good agreement with the theoretical ones. This confirms the conclusion about the satisfactory agreement of observations and models based on the analysis of the continuum. Models give close values of equivalent widths in the range of spectral B4-A1 classes for Hsub(?) line. Values of equivalent widths of all three lines for stars of earlier spectral classes than B4 agree better with the D. Mihalas model. For stars of F spectral class equivalent widths of Hsub(?) lines lie a bit higher than the theoretical values

  11. On the H$\\alpha$ Behaviour of Blue Supergiants: Rise and Fall over the Bi-stability Jump

    CERN Document Server

    Petrov, Blagovest; Gräfener, Götz

    2014-01-01

    The evolutionary state of blue supergiants is still unknown. Stellar wind mass loss is one of the dominant processes determining the evolution of massive stars, and it may provide clues on the evolutionary properties of blue supergiants. As the H$\\alpha$ line is the most oft-used mass-loss tracer in the OB-star regime, we provide a detailed analysis of the H$\\alpha$ line for OB supergiant models over an $T_{\\rm eff}$ range between 30000 and 12500K. We find a maximum in the H$\\alpha$ equivalent width at 22500 K - at the location of the bi-stability jump. The H$\\alpha$ line-profile behaviour is characterised by two branches of $T_{\\rm eff}$: (i) a "hot" branch between 30000 and 22500 K, where H$\\alpha$ emission becomes stronger with decreasing $T_{\\rm eff}$, and (ii) a "cool" branch between 22500 and 12500 K, where the line becomes weaker. Our models show that this non-monotonic H$\\alpha$ behaviour is related to the optical depth of Ly$\\alpha$, finding that at the "cool" branch the population of the 2nd level o...

  12. H$\\alpha$ and EUV observations of a partial CME

    CERN Document Server

    Christian, Damian J; Antolin, Patrick; Mathioudakis, Mihalis

    2015-01-01

    We have obtained H$\\alpha$ high spatial and time resolution observations of the upper solar chromosphere and supplemented these with multi-wavelength observations from the Solar Dynamic Observatory (SDO) and the {\\it Hinode} ExtremeUltraviolet Imaging Spectrometer (EIS). The H$\\alpha$ observations were conducted on 11 February 2012 with the Hydrogen-Alpha Rapid Dynamics Camera (HARDcam) instrument at the National Solar Observatory's Dunn Solar Telescope. Our H$\\alpha$ observations found large downflows of chromospheric material returning from coronal heights following a failed prominence eruption. We have detected several large condensations ("blobs") returning to the solar surface at velocities of $\\approx$200 km s$^{-1}$ in both H$\\alpha$ and several SDO AIA band passes. The average derived size of these "blobs" in H$\\alpha$ is 500 by 3000 km$^2$ in the directions perpendicular and parallel to the direction of travel, respectively. A comparison of our "blob" widths to those found from coronal rain, indicate...

  13. H-alpha Imaging of Early-type (Sa-Sab) Spiral Galaxies II. Global Properties

    CERN Document Server

    Hameed, S; Hameed, Salman; Devereux, Nick

    2005-01-01

    New results, based on one of the most comprehensive H-alpha imaging surveys of nearby Sa-Sab spirals completed to date, reveals early-type spirals to be a diverse group of galaxies that span a wide range in massive star formation rates. While the majority of Sa-Sab galaxies in our sample are forming stars at a modest rate, a significant fraction (~29%) exhibit star formation rates greater than 1 M(solar/yr), rivaling the most prolifically star forming late-type spirals. A similar diversity is apparent in the star formation history of Sa-Sab spirals as measured by their H-alpha equivalent widths. Consistent with our preliminary results presented in the first paper in this series, we find giant HII regions (L(H-alpha)>10^{39}erg/s) in the disks of 37% of early-type spirals. We suspect that recent minor mergers or past interactions are responsible for the elevated levels of H-alpha emission and perhaps, for the presence of giant HII regions in these galaxies.

  14. Joint H-alpha and X-Ray Observations of Massive X-Ray Binaries. II. The Be X-ray Binary and Microquasar LS I +61 303

    OpenAIRE

    Grundstrom, E. D.; Caballero-Nieves, S. M.; Gies, D. R.; W. Huang; McSwain, M.V.; Rafter, S. E.; Riddle, R. L.; Williams, S.J.(TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, V6T 2A3, Canada); Wingert, D.W.

    2006-01-01

    We present the results of an H-alpha monitoring campaign on the BeXRB and microquasar system LS I +61 303. We use radial velocity measurements of HeI lines in our spectra to re-evaluate the orbital elements and to better establish the time of periastron. We list equivalent widths and other parameters for the H-alpha emission line and discuss the orbital phase related variations observed. We call attention to a dramatic episode of emission weakening that occurred in less than...

  15. Multi-slit spectrograph and H alpha Doppler system

    Science.gov (United States)

    Martin, S. F.; Ramsey, H. E.; Carroll, G. A.; Martin, D. C.

    1974-01-01

    Description of the design and operation of a multiple-entrance-slit spectrograph, built for time-lapse photography of the spectra of flares and other transient solar phenomena. This spectrograph employs narrow-band filters to limit the wavelength range of the spectrograph to a few angstroms centered at H-alpha or other spectral lines. A polarizing beamsplitter, prior to the slits, provides a prefiltered second solar image to a narrow band H-alpha Doppler filter for simultaneous photography in the wings of the H-alpha line. The spectrograph and the H-alpha Doppler system constitute a flexible instrument in which components may be substituted to achieve different passband widths, image scales, dispersions, and corresponding numbers and spacings of adjacent spectra at a selected wavelength.

  16. Eddington ratio governs the equivalent width of MgII emission line in active galactic nuclei

    CERN Document Server

    Dong, Xiao-Bo; Wang, Jian-Guo; Fan, Xiaohui; Wang, Huiyuan; Zhou, Hongyan; Yuan, Weimin

    2009-01-01

    We have investigated the ensemble regularities of the equivalent widths (EWs) of MgII 2800 emission line of active galactic nuclei (AGNs), using a uniformly selected sample of 2092 Seyfert 1 galaxies and quasars at 0.45 <= z <= 0.8 in the spectroscopic data set of Sloan Digital Sky Survey Fourth Data Release. We find a strong correlation between the EW of MgII and the AGN Eddington ratio (L/L_Edd): EW(MgII) \\propto (L/L_Edd)^{-0.4}. Furthermore, for AGNs with the same L/L_Edd, their EWs of MgII show no correlation with luminosity, black hole mass or line width, and the MgII line luminosity is proportional to continuum luminosity, as expected by photoionization theory. Our result shows that MgII EW is not dependent on luminosity, but is solely governed by L/L_Edd.

  17. VizieR Online Data Catalog: Equivalent widths of WINGS galaxies (Fritz+, 2014)

    Science.gov (United States)

    Fritz, J.; Poggianti, B. M.; Cava, A.; Moretti, A.; Varela, J.; Bettoni, D.; Couch, W. J.; D'Onofrio, M.; Dressler, A.; Fasano, G.; Kjaergaard, P.; Marziani, P.; Moles, M.; Omizzolo, A.

    2014-02-01

    Equivalent Widths for up to 14 optical lines, measurement uncertainties, the D4000 and Dn4000 index, spectral classification, and magnitude and geometrical completeness are presented for 4861 galaxies in 29 nearby clusters' fields. Galaxies in the following clusters have been included in the catalog: A1069, A119, A151, A1631a, A1644, A2382, A2399, A2415, A3128, A3158, A3266, A3376, A3395, A3490, A3497, A3556, A3560, A3809, A500, A754, A957x, A970, A1795, A1983, A2457, A2626, A376, Z8338 and Z8852. (1 data file).

  18. Bayesian Identification of Emission-Line Galaxies with Photometric Equivalent Widths

    Science.gov (United States)

    Leung, Andrew S.; Gawiser, Eric J.; Acquaviva, Viviana; Hetdex Collaboration

    2015-01-01

    We present a Bayesian approach to the classification of emission-line galaxies as an alternative to the traditional limit of requiring Lyman-alpha emitting (LAE) galaxies to have rest-frame equivalent width (EW) > 20 Angstroms. The Bayesian method relies on known distributions of line luminosities and equivalent widths as prior probabilities and returns the probability that an object is an LAE given the observed characteristics. This will be directly relevant for the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX), which seeks to classify more than a million emission-line galaxies into LAEs and low-redshift [O II] emitters. For a simulated HETDEX catalog with realistic measurement noise, the Bayesian method recovers a majority of the LAEs missed by the EW > 20 Angstroms cutoff over 2 20 Angstroms cut in contamination (false positives) and incompleteness (false negatives). Trade-off between contamination and incompleteness can be achieved by adjusting the stringency of the probability requirement for classifying an observed object as an LAE. A basic implementation of the Bayesian reduces errors in cosmological parameters by ~22%, which is equivalent to obtaining ~40% more data. The inclusion of the color of the galaxies, contingent on the availability of this information, increases the discriminating power of Bayesian separation and results in further reductions in errors. The Bayesian method is also being used to determine which single broadband filter produces the best performance. This method would enable large-scale structure analyses to be performed directly on emission-line objects labeled with probabilities of being LAEs rather than splitting the sample into LAEs and [O II] emitters.We gratefully acknowledge support from NSF through grant AST-1055919.

  19. From HI to Stars: HI Depletion in Starbursts and Star-Forming Galaxies in the ALFALFA H-alpha Survey

    CERN Document Server

    Jaskot, A E; Salzer, J J; Van Sistine, A; Bell, E F; Haynes, M P

    2015-01-01

    HI in galaxies traces the fuel for future star formation and reveals the effects of feedback on neutral gas. Using a statistically uniform, HI-selected sample of 565 galaxies from the ALFALFA H-alpha survey, we explore HI properties as a function of star formation activity. ALFALFA H-alpha provides R-band and H-alpha imaging for a volume-limited subset of the 21-cm ALFALFA survey. We identify eight starbursts based on H-alpha equivalent width and six with enhanced star formation relative to the main sequence. Both starbursts and non-starbursts have similar HI to stellar mass ratios (MHI/M*), which suggests that feedback is not depleting the starbursts' HI. Consequently, the starbursts do have shorter HI depletion times (t_dep), implying more efficient HI-to-H2 conversion. While major mergers likely drive this enhanced efficiency in some starbursts, the lowest mass starbursts may experience periodic bursts, consistent with enhanced scatter in t_dep at low M*. Two starbursts appear to be pre-coalescence mergers...

  20. VizieR Online Data Catalog: Equivalent width of 21 RR Lyrae stars (Pancino+, 2015)

    Science.gov (United States)

    Pancino, E.; Britavskiy, N.; Romano, D.; Cacciari, C.; Mucciarelli, A.; Clementini, G.

    2015-02-01

    Equivalent widths and atomic data of the absorption lines used in the abundance analysis, for each separate exposure at different phases. Observations of 15 RR Lyrae stars (DR And, X Ari, TW Boo, RZ Cam, RX Cet, U Com, RV CrB, SW CVn, UZ CVn, AE Dra, SZ Gem, VX Her, DH Hya, TU UMa, and RV UMa) and one BL Her star (UY Eri) were carried out with SARG@TNG, operated on the island of La Palma, Spain, during two separate runs in 2009 March and between September and November. Eight stars (SW Aqr, TW Cap, DH Hya, V Ind, SS Leo, V716 Oph, BK Tuc, and UV Vir) were observed with UVES@VLT, between 2009 April and August in service mode. (3 data files).

  1. WINGS-SPE III: Equivalent width measurements, spectral properties and evolution of local cluster galaxies

    CERN Document Server

    Fritz, J; Cava, A; Moretti, A; Varela, J; Bettoni, D; Couch, W J; D'Onofrio, M; Dressler, A; Fasano, G; Kjaergaard, P; Marziani, P; Moles, M; Omizzolo, A

    2014-01-01

    [Abridged] We investigate the frequency of the various spectral types as a function both of the clusters' properties and of the galaxies' characteristics. In this way, using the same classification criteria adopted for higher redshift studies, we can consistently compare the properties of the local cluster population to those of their more distant counterparts. We describe a method we have developed to automatically measure the equivalent width of spectral lines in a robust way even in spectra with a non optimal signal to noise. Like this, we can derive a spectral classification reflecting the stellar content, based on the presence and strength of the [OII] and Hdelta lines. We are able to measure 4381 of the ~6000 originally observed spectra, in the fields of 48 clusters, 2744 of which are spectroscopically confirmed cluster members. The spectral classification is then analyzed as a function of galaxies' luminosity, stellar mass, morphology, local density and host cluster's global properties, and compared to...

  2. On the (Non-)Enhancement of the Ly? Equivalent Width by a Multiphase Interstellar Medium

    DEFF Research Database (Denmark)

    Laursen, Peter; Duval, F.

    2013-01-01

    It has been suggested that radiative transfer effects may explain the unusually high equivalent widths (EWs) of the Lya line, observed occasionally from starburst galaxies, especially at high redshifts. If the dust is locked up inside high-density clouds dispersed in an empty intercloud medium, the Lya photons could scatter off of the surfaces of the clouds, effectively having their journey confined to the dustless medium. The continuum radiation, on the other hand, does not scatter, and would thus be subject to absorption inside the clouds. This scenario is routinely invoked when Lya EWs higher than what is expected theoretically are observed, although the ideal conditions under which the results are derived usually are not considered. Here we systematically examine the relevant physical parameters in this idealized framework, testing whether any astrophysically realistic scenarios may lead to such an effect. It is found that although clumpiness indeed facilitates the escape of Lya, it is highly unlikely that any real interstellar media should result in a preferential escape of Lya over continuum radiation. Other possible causes are discussed, and it is concluded that the observed high EWs are more likely to be caused by cooling radiation from cold accretion and/or anisotropic escape of the Lya radiation. © 2013. The American Astronomical Society. All rights reserved.

  3. Ly{\\alpha} Equivalent Width Distribution at Redshift z $\\sim$ 4.5

    CERN Document Server

    Zheng, Zhen-Ya; Malhotra, Sangeeta; Rhoads, James E; Finkelstein, Steven L; Finkelstein, Keely

    2013-01-01

    Ly{\\alpha} line equivalent widths (EWs) provide important clues to the physical nature of high redshift Lyman alpha emitters (LAEs). However, measuring the Ly{\\alpha} EW distribution of high-z narrowband selected LAEs can be hard because many sources do not have broadband photometry. We investigate the possible biases in measuring the intrinsic Ly{\\alpha} EW distribution for a LAE sample at z $\\sim$ 4.5 in the Extended Chandra Deep Field South (ECDFS). Only weak Malmquist-type bias in both the intrinsic Ly{\\alpha} luminosity function and the Ly{\\alpha} EW distribution were found. However, the observed EW distribution is severely biased if one only considers LAEs with detections in the continuum. Taking the broadband non-detections into account requires fitting the distribution of the broadband-to-narrowband ratio, which then gives a larger EW distribution scale length. Assuming an exponential form of the intrinsic Ly{\\alpha} EW distribution dN/dEW = N exp(-EW/W$_0$), we obtain W$_0$ = 167+/-44{\\AA} (uncorrect...

  4. WINGS-SPE. III. Equivalent width measurements, spectral properties, and evolution of local cluster galaxies

    Science.gov (United States)

    Fritz, J.; Poggianti, B. M.; Cava, A.; Moretti, A.; Varela, J.; Bettoni, D.; Couch, W. J.; D'Onofrio D'Onofrio, M.; Dressler, A.; Fasano, G.; Kjærgaard, P.; Marziani, P.; Moles, M.; Omizzolo, A.

    2014-06-01

    Context. Cluster galaxies are the ideal sites to look at when studying the influence of the environment on the various aspects of the evolution of galaxies, such as the changes in their stellar content and morphological transformations. In the framework of wings, the WIde-field Nearby Galaxy-cluster Survey, we have obtained optical spectra for ~6000 galaxies selected in fields centred on 48 local (0.04 automatically measure the equivalent width of spectral lines in a robust way, even in spectra with a non optimal signal-to-noise ratio. This way, we can derive a spectral classification reflecting the stellar content, based on the presence and strength of the [Oii] and H? lines. Results: After a quality check, we are able to measure 4381 of the ~6000 originally observed spectra in the fields of 48 clusters, of which 2744 are spectroscopically confirmed cluster members. The spectral classification is then analysed as a function of galaxies' luminosity, stellar mass, morphology, local density, and host cluster's global properties and compared to higher redshift samples (MORPHS and EDisCS). The vast majority of galaxies in the local clusters population are passive objects, being also the most luminous and massive. At a magnitude limit of MV index.htmlAppendices are available in electronic form at http://www.aanda.org

  5. Ly? EMITTERS IN HIERARCHICAL GALAXY FORMATION. II. ULTRAVIOLET CONTINUUM LUMINOSITY FUNCTION AND EQUIVALENT WIDTH DISTRIBUTION

    International Nuclear Information System (INIS)

    We present theoretical predictions of the UV continuum luminosity function (UV LF) and Ly? equivalent width (EW) distribution of Ly? emitters (LAEs) in the framework of the hierarchical clustering model of galaxy formation. The model parameters for the LAEs were determined by fitting to the observed Ly? LF at z = 5.7 in our previous study, and the fit indicates that extinction of Ly? photons by dust is significantly less effective than that of UV continuum photons, implying a clumpy dust distribution in the interstellar medium. We then compare the predictions about UV LFs and EW distributions with a variety of observations at z? 3-6, allowing no more free parameters and paying careful attention to the selection conditions of LAEs in each survey. We find that the predicted UV LFs and EW distributions are in nice agreement with observed data, and especially, our model naturally reproduces the existence of large EW LAEs (?> 240 A) without introducing Pop III stars or top-heavy initial mass function. We show that both the stellar population (young age and low metallicity) and extinction by clumpy dust are the keys to reproducing large EW LAEs. The evidence of EW enhancement by clumpy dust is further strengthened by the quantitative agreement between our model and recent observations about a positive correlation between EW and extinction. The observed trend that brighter LAEs in the UV continuum tend to have smaller mean EW is also reproduced, and the clumpy dust p reproduced, and the clumpy dust plays an important role again for this trend. We suggested in our previous study that the transmission of the intergalactic medium for Ly? emission rapidly decreases from z ? 6 to 7 by fitting to Ly? LFs, and this evidence is quantitatively strengthened by the comparison with the UV LF and EW distribution at z ? 6.6.

  6. Temporal evolution of mottles observed in H_alpha

    OpenAIRE

    Bostanci, Z. Funda; Erdogan, Nurol Al

    2007-01-01

    In April 2002, H_alpha observations of the solar chromosphere with high spatial and spectral resolution were obtained with the Gottingen Fabry-Perot Spectrometer mounted in the Vacuum Tower Telescope (VTT) at the Observatorio del Teide/Tenerife. In this work, we analyze a short time sequence of a quiet region with chains of mottles. Some physical parameters of dark mottles are determined by using Beckers' cloud model which takes the source function, the Doppler width, and th...

  7. Emission-line stars discovered in the UKST H-alpha survey of the Large Magellanic Cloud; Part 1: Hot stars

    CERN Document Server

    Reid, Warren A

    2012-01-01

    We present new, accurate positions, spectral classifications, radial and rotational velocities, H-alpha fluxes, equivalent widths and B,V,I,R magnitudes for 579 hot emission-line stars (classes B0 - F9) in the Large Magellanic Cloud which include 469 new discoveries. Candidate emission line stars were discovered using a deep, high resolution H-alpha map of the central 25 deg2 of the LMC obtained by median stacking a dozen 2 hour H-alpha exposures taken with the UK Schmidt Telescope. Spectroscopic follow-up observations on the AAT, UKST, VLT, the SAAO 1.9m and the MSSSO 2.3m telescope have established the identity of these faint sources down to magnitude R~23 for H-alpha (4.5 x 10^-17 ergs cm^2 s^-1 Ang). Confirmed emission-line stars have been assigned an underlying spectral classification through cross-correlation against 131 absorption line template spectra covering the range O1 to F8. We confirm 111 previously identified emission line stars and 64 previously known variable stars with spectral types hotter ...

  8. SPATIALLY RESOLVED H{alpha} MAPS AND SIZES OF 57 STRONGLY STAR-FORMING GALAXIES AT z {approx} 1 FROM 3D-HST: EVIDENCE FOR RAPID INSIDE-OUT ASSEMBLY OF DISK GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Erica June; Van Dokkum, Pieter G.; Skelton, Rosalind E.; Bezanson, Rachel; Lundgren, Britt [Astronomy Department, Yale University, New Haven, CT 06511 (United States); Brammer, Gabriel [European Southern Observatory, Alonson de Cordova 3107, Casilla 19001, Vitacura, Santiago (Chile); Foerster Schreiber, Natascha [Max-Planck-Institut fuer extraterrestrische Physik, Giessenbachstrasse, D-85748 Garching (Germany); Franx, Marijn; Fumagalli, Mattia; Patel, Shannon; Labbe, Ivo [Leiden Observatory, Leiden University, Leiden (Netherlands); Rix, Hans-Walter; Da Cunha, Elisabete; Schmidt, Kasper B. [Max Planck Institute for Astronomy (MPIA), Koenigstuhl 17, 69117 Heidelberg (Germany); Kriek, Mariska [Department of Astronomy, University of California, Berkeley, CA 94720 (United States); Quadri, Ryan [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)

    2012-03-10

    We investigate the buildup of galaxies at z {approx} 1 using maps of H{alpha} and stellar continuum emission for a sample of 57 galaxies with rest-frame H{alpha} equivalent widths >100 A in the 3D-HST grism survey. We find that the H{alpha} emission broadly follows the rest-frame R-band light but that it is typically somewhat more extended and clumpy. We quantify the spatial distribution with the half-light radius. The median H{alpha} effective radius r{sub e} (H{alpha}) is 4.2 {+-} 0.1 kpc but the sizes span a large range, from compact objects with r{sub e} (H{alpha}) {approx} 1.0 kpc to extended disks with r{sub e} (H{alpha}) {approx} 15 kpc. Comparing H{alpha} sizes to continuum sizes, we find H{alpha})/r{sub e} (R) > =1.3 {+-} 0.1 for the full sample. That is, star formation, as traced by H{alpha}, typically occurs out to larger radii than the rest-frame R-band stellar continuum; galaxies are growing their radii and building up from the inside out. This effect appears to be somewhat more pronounced for the largest galaxies. Using the measured H{alpha} sizes, we derive star formation rate surface densities, {Sigma}{sub SFR}. We find that {Sigma}{sub SFR} ranges from {approx}0.05 M{sub Sun} yr{sup -1} kpc{sup -2} for the largest galaxies to {approx}5 M{sub Sun} yr{sup -1} kpc{sup -2} for the smallest galaxies, implying a large range in physical conditions in rapidly star-forming z {approx} 1 galaxies. Finally, we infer that all galaxies in the sample have very high gas mass fractions and stellar mass doubling times <500 Myr. Although other explanations are also possible, a straightforward interpretation is that we are simultaneously witnessing the rapid formation of compact bulges and large disks at z {approx} 1.

  9. Temporal evolution of mottles observed in H_alpha

    CERN Document Server

    Bostanci, Z F; Erdogan, Nurol Al

    2007-01-01

    In April 2002, H_alpha observations of the solar chromosphere with high spatial and spectral resolution were obtained with the Gottingen Fabry-Perot Spectrometer mounted in the Vacuum Tower Telescope (VTT) at the Observatorio del Teide/Tenerife. In this work, we analyze a short time sequence of a quiet region with chains of mottles. Some physical parameters of dark mottles are determined by using Beckers' cloud model which takes the source function, the Doppler width, and the velocity to be constant within the cloud along the line of sight. Here, we present the results of our study.

  10. Discovery of Massive, Mostly Star-formation Quenched Galaxies with Extremely Large Lyman-alpha Equivalent Widths at z ~ 3

    CERN Document Server

    Taniguchi, Yoshiaki; Kobayashi, Masakazu A R; Nagao, Tohru; Shioya, Yasuhiro; Scoville, Nick Z; Sanders, David B; Capak, Peter L; Koekemoer, Anton M; Toft, Sune; McCracken, Henry J; Fevre, Olivier Le; Tasca, Lidia; Sheth, Kartik; Renzini, Alvio; Lilly, Simon; Carollo, Marcella; Kovac, Katarina; Ilbert, Olivier; Schinnerer, Eva; Fu, Hai; Tresse, Laurence; Griffiths, Richard E; Civano, Francesca

    2015-01-01

    We report a discovery of 6 massive galaxies with both extremely large Lya equivalent width and evolved stellar population at z ~ 3. These MAssive Extremely STrong Lya emitting Objects (MAESTLOs) have been discovered in our large-volume systematic survey for strong Lya emitters (LAEs) with twelve optical intermediate-band data taken with Subaru/Suprime-Cam in the COSMOS field. Based on the SED fitting analysis for these LAEs, it is found that these MAESTLOs have (1) large rest-frame equivalent width of EW_0(Lya) ~ 100--300 A, (2) M_star ~ 10^10.5--10^11.1 M_sun, and (3) relatively low specific star formation rates of SFR/M_star ~ 0.03--1 Gyr^-1. Three of the 6 MAESTLOs have extended Ly$\\alpha$ emission with a radius of several kpc although they show very compact morphology in the HST/ACS images, which correspond to the rest-frame UV continuum. Since the MAESTLOs do not show any evidence for AGNs, the observed extended Lya emission is likely to be caused by star formation process including the superwind activit...

  11. First results of an H-alpha based search of classical Be stars in the Perseus Arm and beyond

    CERN Document Server

    Raddi, R; Fabregat, J; Steeghs, D; Wright, N J; Sale, S E; Farnhill, H J; Barlow, M J; Greimel, R; Sabin, L; Corradi, R M L; Drake, J J

    2013-01-01

    We investigate a region of the Galactic plane, between 120 <= l <= 140 and -1 <= b <= +4, and uncover a population of moderately reddened (E(B-V) \\sim 1) classical Be stars within and beyond the Perseus and Outer Arms. 370 candidate emission line stars (13 <= r <= 16) selected from the INT Photometric H-alpha Survey of the Northern Galactic plane (IPHAS) have been followed up spectroscopically. A subset of these, 67 stars with properties consistent with those of classical Be stars, have been observed at sufficient spectral resolution (Delta_lambda \\sim 2 - 4 Angstrom) at blue wavelengths to narrow down their spectral types. We determine these to a precision estimated to be +/- 1 sub-type and then we measure reddenings via SED fitting with reference to appropriate model atmospheres. Corrections for contribution to colour excess from circumstellar discs are made using an established scaling to H-alpha emission equivalent width. Spectroscopic parallaxes are obtained after luminosity class has b...

  12. Discovery of a very cool object with extraordinarily strong H(alpha) emission

    CERN Document Server

    Barrado y Navascués, D; Martín, E L; Béjar, V J S; Rebolo, R; Mundt, R; Navascues, David Barrado y; Osorio, Maria Rosa Zapatero; Martin, Eduardo L.; Bejar, Victor J.S.; Rebolo, Rafael; Mundt, Reinhard

    2002-01-01

    We report on the finding of the strongest H(alpha) emission -pseudoequivalent width of 705 Angstrom- known so far in a young, late type dwarf. This object, named as SOri71, is a substellar candidate member of the 1-8 Myr star cluster sigma Orionis. Due to its overluminous location in color-magnitude diagrams, SOri71 might be younger than other cluster members, or a binary of similar components. Its mass is in the range 0.021-0.012 M(sun), depending on evolutionary models and possible binarity. The broad H(alpha) line of SOri71 appears asymmetric, indicative of high velocity mass motions in the H(alpha) forming region. The origin of this emission is unclear at the present time. We discuss three possible scenarios: accretion from a disk, mass exchange between the components of a binary system, and emission from a chromosphere.

  13. On the equivalent width of the Fe K$\\alpha$ line produced by a dusty absorber in active galactic nuclei

    CERN Document Server

    Gohil, Raj

    2015-01-01

    Obscured AGNs provide an opportunity to study the material surrounding the central engine. Geometric and physical constraints on the absorber can be deduced from the reprocessed AGN emission. In particular, the obscuring gas may reprocess the nuclear X-ray emission producing a narrow Fe K$\\alpha$ line and a Compton reflection hump. In recent years, models of the X-ray reflection from an obscuring torus have been computed; however, although the reflecting gas may be dusty, the models do not yet take into account the effects of dust on the predicted spectrum. We study this problem by analyzing two sets of models, with and without the presence of dust, using the one dimensional photo-ionization code Cloudy. The calculations are performed for a range of column densities ($22 <{\\rm log}[N_H(\\rm cm^{-2})]< 24.5$ ) and hydrogen densities ( $6 <{\\rm log}[n_H(\\rm cm^{-3})]< 8$). The calculations show the presence of dust can enhance the Fe K$\\alpha$ equivalent width (EW) in the reflected spectrum by factor...

  14. Halpha Equivalent Widths from the 3D-HST survey: evolution with redshift and dependence on stellar mass

    CERN Document Server

    Fumagalli, Mattia; Franx, Marijn; Brammer, Gabriel; van Dokkum, Pieter; da Cunha, Elisabete; Kriek, Mariska; Lundgren, Britt; Momcheva, Ivelina; Rix, Hans-Walter; Schmidt, Kasper B; Skelton, Rosalind E; Whitaker, Katherine E; Labbe, Ivo; Nelson, Erica

    2012-01-01

    We investigate the evolution of the Halpha equivalent width, EW(Halpha), with redshift and its dependence on stellar mass, taking advantage of the first data from the 3D-HST survey, a large spectroscopic Treasury program with the Hubble Space Telescope WFC3. Combining our Halpha measurements of 854 galaxies at 0.8

  15. The KPNO International Spectroscopic Survey. II. H-alpha Selected Survey List 1

    CERN Document Server

    Salzer, J J; Lipovetsky, V A; Kniazev, A Yu; Moody, J W; Boroson, T A; Thuan, T X; Izotov, Yu I; Herrero, J L; Frattare, L M

    2000-01-01

    The KPNO International Spectroscopic Survey (KISS) is a new objective-prism survey for extragalactic emission-line objects. It combines many of the features of previous slitless spectroscopic surveys with the advantages of modern CCD detectors, and is the first purely digital objective-prism survey for emission-line galaxies. Here we present the first list of emission-line galaxy candidates selected from our red spectral data, which cover the spectral range 6400 to 7200 Angstroms. In most cases, the detected emission line is H-alpha. The current survey list covers a one-degree-wide strip located at Dec (1950) = 29.5 degrees and spanning the RA range 12h 15m to 17h 0m. An area of 62.2 sq. degrees is covered. A total of 1128 candidate emission-line objects have been selected for inclusion in the survey list (18.1 per sq. degree). We tabulate accurate coordinates and photometry for each source, as well as estimates of the redshift and emission-line flux and equivalent width based on measurements of the digital o...

  16. H$\\alpha$ kinematics of KPG 390

    CERN Document Server

    Repetto, P; Fuentes-Carrera, R Gabbasov I

    2009-01-01

    In this work we present scanning Fabry-Perot H$\\alpha$ observations of the isolated interacting galaxy pair NGC 5278/79 obtained with the PUMA Fabry-Perot interferometer. We derived velocity fields, various kinematic parameters and rotation curves for both galaxies. Our kinematical results together with the fact that dust lanes have been detected in both galaxies, as well as the analysis of surface brightness profiles along the minor axis, allowed us to determine that both components of the interacting pair are trailing spirals.

  17. H$\\alpha$ and EUV observations of a partial CME

    OpenAIRE

    Christian, Damian J.; Jess, David B.; Antolin, Patrick; Mathioudakis, Mihalis

    2015-01-01

    We have obtained H$\\alpha$ high spatial and time resolution observations of the upper solar chromosphere and supplemented these with multi-wavelength observations from the Solar Dynamic Observatory (SDO) and the {\\it Hinode} ExtremeUltraviolet Imaging Spectrometer (EIS). The H$\\alpha$ observations were conducted on 11 February 2012 with the Hydrogen-Alpha Rapid Dynamics Camera (HARDcam) instrument at the National Solar Observatory's Dunn Solar Telescope. Our H$\\alpha$ observ...

  18. Spectral energy distributions and equivalent widths of Balmer lines of B and A stars with rapid axial rotation. Comparison with theoretical models

    International Nuclear Information System (INIS)

    The characteristics of the continuous spectrum (spectrophotometric gradients, Balmer jumps) and the equivalent widths of H?, H#betta#, and H#betta# Balmer lines of rapidly rotating stars are investigated. A comparison is made with the analogous characteristics for stars with low rotation rates and with theoretical values calculated from models of rotating stars. The limits of variation of the angle of orientation of the rotation axis are determined for several stars on the basis of a comparison with models

  19. Measurements of the equivalent width of the Hsub(?) emission line and age determination of HII regions of the LMC and SMC

    International Nuclear Information System (INIS)

    The equivalent width of the emission line Hsub(?) was measured photoelectrically in 29 H II regions of the LMC and 2 of the SMC respectively. The age of these regions was obtained trough a calibration of Wsub(H)sub(?). A relation was found between Wsub(H)sub(?) and the ratio of the H II region radius to that of the embedded stellar association.

  20. The H alpha Galaxy Survey. III. Constraints on supernova progenitors from spatial correlations with H alpha emission

    OpenAIRE

    James, P. A.; Anderson, J. P.

    2006-01-01

    Aims: We attempt to constrain progenitors of the different types of supernovae from their spatial distributions relative to star formation regions in their host galaxies, as traced by H alpha + NII line emission. Methods: We analyse 63 supernovae which have occurred within galaxies from our H alpha survey of the local Universe. Three statistical tests are used, based on pixel statistics, H alpha radial growth curves, and total galaxy emission-line fluxes. Results: Man...

  1. Probing the atmosphere of the bulge G5III star OGLE-2002-BUL-069 by analysis of microlense H alpha line

    CERN Document Server

    Cassan, A; Brillant, S; Coutures, C; Dominik, M; Donatowicz, J; Jørgensen, U G; Kubas, D; Albrow, M D; Caldwell, J A R; Fouqué, P; Greenhill, J; Hill, K; Horne, K; Kane, S; Martin, R; Menzies, J; Pollard, K R; Sahu, K C; Vinter, C; Wambsganss, J; Watson, R; Williams, A; Fendt, C; Hauschildt, P H; Heinmueller, J; Marquette, J B; Thurl, C

    2004-01-01

    We discuss high-resolution, time-resolved spectra of the binary microlensing event OGLE 2002-BUL-69 obtained with UVES on the VLT. The source star is a G5III giant in the Galactic Bulge. During such events, the sour ce star is highly magnified, and a strong differential magnification around the caustic resolves its surface. Using an appropriate model stellar atmosphere generated by the NextGEN code we obtained a model light curve for the caustic exit and compared it with a dense set of photometric observations obtained by the PLANET microlensing follow up network. We further compared predicted variations in the H alpha equivalent width with those measured from our spectra. While the model and observations agree in the gross features, there are discrepancies suggesting shortcomings in the model, particularly for the H alpha line core, where we have detected amplified emission from the stellar chromosphere as the source star's trailing limb exited the caustic. This achievement became possible by the provision o...

  2. Kelvin--Helmholtz instability in solar H-alpha surges

    CERN Document Server

    Zhelyazkov, I; Chandra, R; Srivastava, A K; Mishonov, T

    2015-01-01

    We study the evolutionary conditions for Kelvin--Helmholtz (KH) instability in a H-alpha solar surge observed in NOAA AR 8227 on 1998 May 30. The jet with speeds in the range of 45--50 km/s, width of 7 Mm, and electron number density of 3.83 x 10^{10} cm^{-3} is assumed to be confined in a twisted magnetic flux tube embedded in a magnetic field of 7 G. The temperature of the plasma flow is of the order of 10^5 K while that of its environment is taken to be 2 x 10^6 K. The electron number density of surrounding magnetized plasma has a typical for the TR/lower corona region value of 2 x 10^{9} cm^{-3}. Under these conditions, the Alfven speed inside the jet is equal to 78.3 km/s. We model the surge as a moving magnetic flux tube for two magnetic field configurations: (i) a twisted tube surrounded by plasma with homogeneous background magnetic field, and (ii) a twisted tube which environment is plasma with also twisted magnetic field. The magnetic field twist in given region is characterized by the ratio of azim...

  3. New perspectives on strong z=0.5 MgII absorbers: are halo-mass and equivalent width anti-correlated?

    CERN Document Server

    Bouche, N; Peroux, C; Csabai, I; Wild, V; Bouche, Nicolas; Murphy, Michael T.; Peroux, Celine; Csabai, Istvan; Wild, Vivienne

    2006-01-01

    We measure the mean halo-mass of z=0.5 MgII absorbers using the cross-correlation (over co-moving scales 0.05-13h^{-1}Mpc) between 1806 MgII quasar absorption systems and ~250,000 Luminous Red Galaxies (LRGs), both selected from the SDSS DR3. The MgII systems have rest-frame equivalent widths W_r(2796)>=0.3A. From the ratio of the MgII-LRG cross-correlation to the LRG-LRG auto-correlation, we find that the bias ratio between MgII absorbers and LRGs is 0.65+/-0.08, which implies that the absorber host-galaxies have a mean halo-mass 20-40 times smaller than that of the LRGs; the MgII absorbers have halos of mean mass =11.94+/-0.31(stat)+/-0.25(sys). We demonstrate that this statistical technique, which does not require any spectroscopic follow-up, does not suffer from contaminants such as stars or foreground and background galaxies. Finally, we find that the absorber halo-mass is anti-correlated with the equivalent width. If MgII absorbers were virialized in galaxy halos a positive M_h-W_r correlation would hav...

  4. Behavior of H-alpha in Delta Cephei

    International Nuclear Information System (INIS)

    A new radial velocity curve for Delta Cep is presented based on 10 A/mm red spectrograms. The curves for neutral metallic lines, low excitation ions, and high excitation Si II lines follow the curve of Shane (1958) within observational uncertainties. For H-alpha the curve shows an amplitude 15 km/s larger than for the metallic lines. Arguments are presented to show that the H-alpha absorption is formed high in the atmosphere of Delta Cep

  5. Galactic Free-free and H-alpha Emission

    OpenAIRE

    Smoot, George F.

    1998-01-01

    This document provides a brief summary estimate of Galactic free-free emission and H-alpha emission and their relationship. Particular emphasis is placed on estimating the potential free-free emission in the region of significant confusion for CMB anisotropy measurements. Existing x-ray, ultraviolet and H$\\alpha$ emission provide limits on the radio free-free emission and vice versa. These limits are generally somewhat smaller than the observed ``free-free'' (signal proporti...

  6. Flux calibration of the AAO/UKST SuperCOSMOS H-alpha Survey

    CERN Document Server

    Frew, David J; Parker, Quentin A; Pierce, Mark J; Gunawardhana, M L P; Reid, W A

    2013-01-01

    The AAO/UKST SuperCOSMOS H-alpha Survey (SHS) of the southern Galactic plane was, when completed in 2003, a powerful new addition to wide-field surveys. It has a combination of areal coverage, spatial resolution and flux sensitivity in a narrow imaging band which still marks it out today as an excellent resource for the astronomical community. The 233 separate fields are available online in digital form, with each field covering 25 square degrees. The SHS has been the motivation for equivalent surveys in the north, and new digital H-alpha surveys now beginning in the south such as VPHAS+. The SHS has been the foundation of many important follow-up discovery projects in the southern sky with the Macquarie/AAO/Strasbourg H-alpha (MASH) planetary nebula project being a particularly successful example. However, the full astrophysical potential of the SHS has been hampered by lack of a clear route to acceptable flux calibration from the base photographic data. We have determined the calibration factors for 170 sep...

  7. A Ly? EMITTER WITH AN EXTREMELY LARGE REST-FRAME EQUIVALENT WIDTH OF ?900 Å AT z = 6.5: A CANDIDATE POPULATION III-DOMINATED GALAXY?

    International Nuclear Information System (INIS)

    We have identified a very interesting Ly? emitter (LAE), whose Ly? emission line has an extremely large observed equivalent width of EW0 = 436+422–149 Å, which corresponds to an extraordinarily large intrinsic rest-frame equivalent width of EWint0 = 872+844–298 Å after the average intergalactic absorption correction. The object was spectroscopically confirmed to be a real LAE by its apparent asymmetric Ly? line profile detected at z = 6.538. The continuum emission of the object was definitely detected in our deep z'-band image; thus, its EW0 was reliably determined. Follow-up deep near-infrared spectroscopy revealed emission lines of neither He II ?1640 as an apparent signature of Population III (Pop III) nor C IV ?1549 as proof of an active nucleus. No detection of the short-lived He II ?1640 line is not necessarily inconsistent with the interpretation that the underlying stellar population of the object is dominated by Pop III. We found that the observed extremely large EW0 of the Ly? emission and the upper limit on the EW0 of the He II ?1640 emission can be explained by population synthesis models favoring a very young age less than 2-4 Myr and massive metal-poor (Z –5) or even metal-free stars. The observed large EW0 of Ly? is insufficiently explained by Population I/II synthesis models with II synthesis models with Z ? 10–3. However, we cannot conclusively rule out the possibility that this object is composed of a normal stellar population with a clumpy dust distribution, which could enhance the Ly? EW0, though its significance is still unclear.

  8. H-alpha observations of four novae in M31

    Science.gov (United States)

    Jacoby, G.; Ciardullo, R.; Ford, H.

    1983-01-01

    On-line off-line H-alpha plates of M31's nucleus revealed four bright stellar objects (m sub R being approximately 14.9, 15.0, 15.8, 16.4) within 1.2 kpc of the galaxy center. Spectrophotometric observations made 10 days later showed the stars were novae in the stage of early decline. In the 10 day interval, the H-alpha emission from these novae faded less than a magnitude, despite the fact that their continua had long since faded from view. The high luminosity and long decay time of the H-alpha emission suggest it might make an excellent standard candle for extragalactic distance measurements.

  9. H{alpha} ABSORPTION IN TRANSITING EXOPLANET ATMOSPHERES

    Energy Technology Data Exchange (ETDEWEB)

    Christie, Duncan; Arras, Phil; Li Zhiyun, E-mail: dac5zm@virginia.edu, E-mail: pla7y@virginia.edu, E-mail: zl4h@virginia.edu [Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325 (United States)

    2013-08-01

    Absorption of stellar H{alpha} by the upper atmosphere of the planet HD 189733b has recently been detected by Jensen et al. Motivated by this observation, we have developed a model for atomic hydrogen in the n = 2 state and compared the resulting H{alpha} line profile to the observations. The model atmosphere is in hydrostatic balance, as well as thermal and photoionization equilibrium. Collisional and radiative transitions are included in the determination of the n = 2 state level population. We find that H{alpha} absorption is dominated by an optical depth {tau} {approx} 1 shell, composed of hydrogen in the metastable 2s state that is located below the hydrogen ionization layer. The number density of the 2s state within the shell is found to vary slowly with radius, while that of the 1s state falls rapidly. Thus while the Ly{alpha} absorption, for a certain wavelength, occurs inside a relatively well defined impact parameter, the contribution to H{alpha} absorption is roughly uniform over the entire atomic hydrogen layer. The model can approximately reproduce the observed Ly{alpha} and H{alpha} integrated transit depths for HD 189733b by using an ionization rate enhanced over that expected for the star by an order of magnitude. For HD 209458b, we are unable to explain the asymmetric H{alpha} line profile observed by Jensen et al., as the model produces a symmetric line profile with transit depth comparable to that of HD 189733b. In an appendix, we study the effect of the stellar Ly{alpha} absorption on the net cooling rate.

  10. H-alpha Spectral diversity of type II supernovae

    DEFF Research Database (Denmark)

    P. Gutiérrez, Claudia; P. Anderson, Joseph

    2014-01-01

    We present a spectroscopic analysis of the H-alpha profiles of hydrogen-rich type II supernovae. A total of 52 type II supernovae having well sampled optical light curves and spectral sequences were analyzed. Concentrating on the H-alpha P-Cygni profile we measure its velocity from the FWHM of emission and the ratio of absorption to emission (a/e) at a common epoch at the start of the recombination phase, and search for correlations between these spectral parameters and photometric properties of the V-band light curves. Testing the strength of various correlations we find that a/e appears to be the dominant spectral parameter in terms of describing the diversity in our measured supernova properties. It is found that supernovae with smaller a/e have higher H-alpha velocities, more rapidly declining light curves from maximum, during the plateau and radioactive tail phase, are brighter at maximum light and have shorter optically thick phase durations. We discuss possible explanations of these results in terms ofphysical properties of type II supernovae, speculating that the most likely parameters which influence the morphologies of H-alpha profiles are the mass and density profile of the hydrogen envelope, together with additional emission components due to circumstellar interaction.

  11. Energy distribution in the spectra and equivalent widths of Balmer lines of B and A rapidly rotating stars. Comparison with theoretical models

    International Nuclear Information System (INIS)

    The characteristics of the continuum (spectrophotometric gradients, Balmer jumps) and equivalent widths of Balmer lines Hsub(?), Hsub(?), Hsub(?) in the spectra of B and A rapidly rotating stars are investigated. The comparison with these characteristics for slowly rotating stars and with theoretical models for rapidly rorating stars are presented. On the basis of the comparison with the models, the limits of change of the orientation angle is determined for some stars. It is shown that differences of average values of spectrophotometric gradients for stars with high and low rotation velocities are rather small. For stars with maximum rotation velocities however the difference of gradients from average values is much greater. As a rule, averaged gradient values for stars with high rotation velocities are greater than for stars with low ones, i. e. they correspond to lower temperatures. Spectrophotometric gradients in ultraviolet and blue spectrum region for stars with low rotation velocities are in worse agreement with theoretical models for stars of the spectral class A than the gradients in visible and red regions

  12. Joint H-alpha and X-Ray Observations of Massive X-Ray Binaries. III. The Be X-ray Binaries HDE 245770 = A 0535+26 and X Persei

    CERN Document Server

    Grundstrom, E D; Finch, C; Gies, D R; Huang, W; McSwain, M V; O'Brien, D P; Riddle, R L; Trippe, M L; Williams, S J; Wingert, D W; Zaballa, R A

    2007-01-01

    We present results from an H-alpha monitoring campaign of the Be X-ray binary systems HDE 245770 = A 0535+26 and X Per. We use the H-alpha equivalent widths together with adopted values of the Be star effective temperature, disk inclination, and disk outer boundary to determine the half-maximum emission radius of the disk as a function of time. The observations of HDE 245770 document the rapid spectral variability that apparently accompanied the regeneration of a new circumstellar disk. This disk grew rapidly during the years 1998 - 2000, but then slowed in growth in subsequent years. The outer disk radius is probably truncated by resonances between the disk gas and neutron star orbital periods. Two recent X-ray outbursts appear to coincide with the largest disk half-maximum emission radius attained over the last decade. Our observations of X Per indicate that its circumstellar disk has recently grown to near record proportions, and concurrently the system has dramatically increased in X-ray flux, presumably ...

  13. Filament and Flare Detection in H{\\alpha} image sequences

    CERN Document Server

    Riegler, Gernot; Pötzi, Werner; Veronig, Astrid

    2013-01-01

    Solar storms can have a major impact on the infrastructure of the earth. Some of the causing events are observable from ground in the H{\\alpha} spectral line. In this paper we propose a new method for the simultaneous detection of flares and filaments in H{\\alpha} image sequences. Therefore we perform several preprocessing steps to enhance and normalize the images. Based on the intensity values we segment the image by a variational approach. In a final postprecessing step we derive essential properties to classify the events and further demonstrate the performance by comparing our obtained results to the data annotated by an expert. The information produced by our method can be used for near real-time alerts and the statistical analysis of existing data by solar physicists.

  14. Galactic Plane H$\\alpha$ Surveys: IPHAS & VPHAS+

    CERN Document Server

    Wright, Nicholas J

    2015-01-01

    The optical Galactic Plane H$\\alpha$ surveys IPHAS and VPHAS+ are dramatically improving our understanding of Galactic stellar populations and stellar evolution by providing large samples of stars in short lived, but important, evolutionary phases, and high quality homogeneous photometry and images over the entire Galactic Plane. Here I summarise some of the contributions these surveys have already made to our understanding of a number of key areas of stellar and Galactic astronomy.

  15. Spectral Properties From Lyman-alpha to H-alpha For An Essentially Complete Sample of Quasars I: Data

    CERN Document Server

    Shang, Z; Wills, D; Brotherton, M S; Shang, Zhaohui; Wills, Beverley J.; Brotherton, Michael S.

    2007-01-01

    We have obtained quasi-simultaneous ultraviolet-optical spectra for 22 out of 23 quasars in the complete PG-X-ray sample with redshift, z<0.4, and M_B<-23. The spectra cover rest-frame wavelengths from at least Lyman-alpha to H-alpha. Here we provide a detailed description of the data, including careful spectrophotometry and redshift determination. We also present direct measurements of the continua, strong emission lines and features, including Lyman-alpha, SiIV+OIV], CIV, CIII], SiIII], MgII, H-beta, [OIII], He5876+NaI5890,5896, H-alpha, and blended iron emission in the UV and optical. The widths, asymmetries and velocity shifts of profiles of strong emission lines show that CIV and Lyman-alpha are very different from H-beta and H-alpha. This suggests that the motion of the broad line region is related to the ionization structure, but the data appears not agree with the radially stratified ionization structure supported by reverberation mapping studies, and therefore suggest that outflows contribute a...

  16. A DETECTION OF H{alpha} IN AN EXOPLANETARY EXOSPHERE

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Adam G.; Redfield, Seth [Van Vleck Observatory, Astronomy Department, Wesleyan University, 96 Foss Hill Drive, Middletown, CT 06459 (United States); Endl, Michael; Cochran, William D.; Koesterke, Lars [Department of Astronomy, University of Texas, Austin, TX 78712 (United States); Barman, Travis, E-mail: Adam.Jensen@gmail.com, E-mail: sredfield@wesleyan.edu, E-mail: mike@astro.as.utexas.edu, E-mail: wdc@astro.as.utexas.edu, E-mail: lars@tacc.utexas.edu, E-mail: barman@lowell.edu [Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States)

    2012-06-01

    We report on a search for H{alpha} absorption in four exoplanets. Strong features at H{alpha} are observed in the transmission spectra of both HD 189733b and HD 209458b. We attempt to characterize and remove the effects of stellar variability in HD 189733b, and along with an empirical Monte Carlo test the results imply a statistically significant transit-dependent feature of (- 8.72 {+-} 1.48) Multiplication-Sign 10{sup -4} integrated over a 16 A band relative to the adjacent continuum. We interpret this as the first detection of this line in an exoplanetary atmosphere. A previous detection of Ly{alpha} in HD 189733b's atmosphere allows us to calculate an excitation temperature for hydrogen, T{sub exc} = 2.6 Multiplication-Sign 10{sup 4} K. This calculation depends significantly on certain simplifying assumptions. We explore these assumptions and argue that T{sub exc} is very likely much greater than the radiative equilibrium temperature (the temperature the planet is assumed to be at based on stellar radiation and the planetary distance) of HD 189733b. A large T{sub exc} implies a very low density that is not in thermodynamic equilibrium with the planet's lower atmosphere. We argue that the n = 2 hydrogen required to cause H{alpha} absorption in the atmosphere is created as a result of the greater UV flux at HD 189733b, which has the smallest orbit and most chromospherically active central star in our sample. Though the overall integration of HD 209458b's transmission spectrum over a wide band is consistent with zero, it contains a dramatic, statistically significant feature in the transmission spectrum with reflectional symmetry. We discuss possible physical processes that could cause this feature. Our remaining two targets (HD 147506b and HD 149026b) do not show any clear features, so we place upper limits on their H{alpha} absorption levels.

  17. Solar H-alpha Oscillations from Intensity and Doppler Observations

    CERN Document Server

    Jackiewicz, J

    2013-01-01

    Chromospheric wave activity around flares and filaments has been a research focus for years, and could provide indirect measurements of local conditions that are not otherwise accessible. One interesting observed phenomenon is oscillations in filaments, activated by distant flares and the large-scale waves they produce. Characteristics of these oscillations, such as periods, amplitudes, and lifetimes, can provide unique information about the filament. We measure oscillation properties in flares and filaments from H-alpha chromospheric data using a new method that provides important spatial and frequency content of the dynamics. We apply the method to two flare events where filaments are observed to oscillate and determine their properties. We find strong oscillatory signal in flaring active regions in the chromosphere over a range of frequencies. Two filaments are found to oscillate without any detectable chromospheric wave acting as an activation mechanism. We find that filaments oscillate with periods of te...

  18. The interacting galaxy pair KPG 390: H$\\alpha$ kinematics

    CERN Document Server

    Repetto, P; Gabbasov, R; Fuentes-Carrera, I

    2010-01-01

    In this work we present scanning Fabry-Perot H$\\alpha$ observations of the isolated interacting galaxy pair NGC 5278/79 obtained with the PUMA Fabry-Perot interferometer. We derived velocity fields and rotation curves for both galaxies. For NGC 5278 we also obtained the residual velocity map to investigate the non-circular motions, and estimated its mass by fitting the rotation curve with a disk+halo components. We test three different types of halo (pseudo-isothermal, Hernquist and Navarro Frenk White) and obtain satisfactory fits to the rotation curve for all profiles. The amount of dark matter required by pseudo-isothermal profile is about ten times smaller than, that for the other two halo distributions. Finally, our kinematical results together with the analysis of dust lanes distribution and of surface brightness profiles along the minor axis allowed us to determine univocally that both components of the interacting pair are trailing spirals.

  19. On the Origins of the High-Latitude H-alpha Background

    CERN Document Server

    Witt, A N; Barnes, F S; DeRoo, C T; Vijh, U P; Madsen, G J

    2010-01-01

    The diffuse high-latitude H-alpha background is widely believed to be predominantly the result of in-situ recombination of ionized hydrogen in the warm interstellar medium of the Galaxy. Instead, we show that both a substantial fraction of the diffuse high-latitude H-alpha intensity in regions dominated by Galactic cirrus dust and much of the variance in the high-latitude H-alpha background are the result of scattering by interstellar dust of H-alpha photons originating elsewhere in the Galaxy. We provide an empirical relation, which relates the expected scattered H-alpha intensity to the IRAS 100um diffuse background intensity, applicable to about 81% of the entire sky. The assumption commonly made in reductions of CMB observations, namely that the observed all-sky map of diffuse H-alpha light is a suitable template for Galactic free-free foreground emission, is found to be in need of reexamination.

  20. The interstellar medium of M31. III - Narrow-band imagery in H alpha and (SII)

    Science.gov (United States)

    Walterbos, R. A. M.; Braun, R.

    1992-01-01

    Deep CCD imagery in H alpha and (SII) is presented of the major spiral arms of M31 with particular attention given to the data reduction and the analysis of the (SII)/H alpha flux ratios. A diffuse ionized gas noted in the images is analyzed which shows higher (SII)/H alpha ratios, and 967 discrete nebulae are listed with gray-scale images, finding charts, and absolute fluxes. The differential H-alpha luminosity function is found to have a slope of -0.95 for brighter objects and flattens out below a critical level. The curve is shown to correspond to the point at which single-star ionization accounts for the H alpha luminosities and is consistent with previous observations. The catalog of objects and fluxes is the largest existing sample of this type, and the unresolved objects in the sample are considered to be planetary nebulae.

  1. A Ly-alpha Emitter with an Extremely Large Rest-frame Equivalent Width of ~900A at z=6.5: A Candidate of Population III-dominated Galaxy?

    CERN Document Server

    Kashikawa, Nobunari; Toshikawa, Jun; Ishizaki, Yoshifumi; Egami, Eiichi; Hayashi, Masao; Ly, Chun; Malkan, Matthew A; Matsuda, Yuichi; Shimasaku, Kazuhiro; Iye, Masanori; Ota, Kazuaki; Shibuya, Takatoshi; Jiang, Linhua; Taniguchi, Yoshiaki; Shioya, Yasuhiro

    2012-01-01

    We have identified a very interesting Ly-alpha emitter, whose Ly-alpha emission line has an extremely large observed equivalent width of EW_0=436^{+422}_{-149}A, which corresponds to an extraordinarily large intrinsic rest-frame equivalent width of EW_0^{int}=872^{+844}_{-298}A after the average intergalactic absorption correction. The object was spectroscopically confirmed to be a real Ly-alpha emitter by its apparent asymmetric Ly-alpha line profile detected at z=6.538. The continuum emission of the object was definitely detected in our deep z'-band image; thus, its EW_0 was reliably determined. Follow-up deep near-infrared spectroscopy revealed emission lines of neither He II lambda1640 as an apparent signature of Population III, nor C IV lambda1549 as a proof of active nucleus. No detection of short-lived He II lambda1640 line is not necessarily inconsistent with the interpretation that the underlying stellar population of the object is dominated by Population III. We found that the observed extremely lar...

  2. The H-alpha Luminosity Function and Star-Formation Rate Volume Density at z=0.8 from the NEWFIRM H-alpha Survey

    CERN Document Server

    Ly, Chun; Dale, Daniel A; Momcheva, Ivelina; Salim, Samir; Staudaher, Shawn; Moore, Carolynn A; Finn, Rose

    2010-01-01

    [Abridged] We present new measurements of the H-alpha luminosity function (LF) and SFR volume density for galaxies at z~0.8. Our analysis is based on 1.18$\\mu$m narrowband data from the NEWFIRM H-alpha Survey, a comprehensive program designed to capture deep samples of intermediate redshift emission-line galaxies using narrowband imaging in the near-infrared. The combination of depth ($\\approx1.9\\times10^{-17}$ erg s$^{-1}$ cm$^{-2}$ in H-alpha at 3$\\sigma$) and areal coverage (0.82 deg$^2$) complements other recent H-alpha studies at similar redshifts, and enables us to minimize the impact of cosmic variance and place robust constraints on the shape of the LF. The present sample contains 818 NB118 excess objects, 394 of which are selected as H-alpha emitters. Optical spectroscopy has been obtained for 62% of the NB118 excess objects. Empirical optical broadband color classification is used to sort the remainder of the sample. A comparison of the LFs constructed for the four individual fields reveals signific...

  3. Observatons of NGC 3077 Galaxy in Narrow Band [SII] and H_alpha Filters

    CERN Document Server

    Andjelic, M; Arbutina, B; Ilic, D; Urosevic, D

    2011-01-01

    We present observations of the HI tidal arm near dwarf galaxy NGC 3077 (member of the M81 galaxy group) in narrow band [SII] and H_alpha filters. Observations were carried out in March 2011 with the 2m RCC telescope at NAO Rozhen, Bulgaria. Our search for possible supernova remnant candidates (identified as sources with enhanced [SII] emission relative to their H_alpha emission) in this region yielded no sources of this kind. Nevertheless, we found a number of objects with significant H_alpha emission that probably represent uncatalogued, low brightness HII regions.

  4. On the Sensitivity of the H$\\alpha$ Scattering Polarization to Chromospheric Magnetism

    OpenAIRE

    Stepan, Jiri; Bueno, Javier Trujillo

    2010-01-01

    A particularly interesting line for exploring the physical conditions of the quiet solar chromosphere is H$\\alpha$, but its intensity profile is magnetically insensitive and the small circular polarization signatures produced by the longitudinal Zeeman effect come mainly from the underlying photosphere. Here we show that the Hanle effect in H$\\alpha$ provides quantitative information on the magnetism of the quiet chromosphere. To this end, we calculate the response function ...

  5. Dust Attenuation and H-alpha Star Formation Rates of z~0.5 Galaxies

    CERN Document Server

    Ly, Chun; Kashikawa, Nobunari; Ota, Kazuaki; Shimasaku, Kazuhiro; Iye, Masanori; Currie, Thayne

    2012-01-01

    Using deep narrow-band and broad-band imaging, we identify 401 z~0.40 and 249 z~0.49 H-alpha line-emitting galaxies in the Subaru Deep Field. Compared to other H-alpha surveys at similar redshifts, our samples are unique since they probe lower H-alpha luminosities, are augmented with multi-wavelength (rest-frame 1000AA--1.5 microns) coverage, and a large fraction (20%) of our samples has already been spectroscopically confirmed. Our spectra allow us to measure the Balmer decrement for nearly 60 galaxies with H-beta detected above 5-sigma. The Balmer decrements indicate an average extinction of A(H-alpha)=0.7^{+1.4}_{-0.7} mag. We find that the Balmer decrement systematically increases with higher H-alpha luminosities and with larger stellar masses, in agreement with previous studies with sparser samples. We find that the SFRs estimated from modeling the spectral energy distribution (SED) is reliable---we derived an "intrinsic" H-alpha luminosity which is then reddened assuming the color excess from SED modeli...

  6. Extracting H$\\alpha$ flux from photometric data in the J-PLUS survey

    CERN Document Server

    Vilella-Rojo, G; López-Sanjuan, C; Cenarro, A J; Varela, J; Díaz-García, L A; Cristóbal-Hornillos, D; Ederoclite, A; Marín-Franch, A; Moles, M

    2015-01-01

    We present the main steps that will be taken to extract H$\\alpha$ emission flux from Javalambre Photometric Local Universe Survey (J-PLUS) photometric data. For galaxies with $z\\lesssim0.015$, the H$\\alpha$+[NII] emission is covered by the J-PLUS narrow-band filter $F660$. We explore three different methods to extract the H$\\alpha$ + [NII] flux from J-PLUS photometric data: a combination of a broad-band and a narrow-band filter ($r'$ and $F660$), two broad-band and a narrow-band one ($r'$, $i'$ and $F660$), and a SED-fitting based method using 8 photometric points. To test these methodologies, we simulated J-PLUS data from a sample of 7511 SDSS spectra with measured H$\\alpha$ flux. Based on the same sample, we derive two empirical relations to correct the derived H$\\alpha$+[NII] flux from dust extinction and [NII] contamination. We find that the only unbiased method is the SED fitting based one. The combination of two filters underestimates the measurements of the H$\\alpha$ + [NII] flux by a 28%, while the th...

  7. The Wyoming Survey for H-alpha. III. H-alpha Luminosity Functions at z ~ 0.16, 0.24, 0.32, and 0.40

    CERN Document Server

    Dale, Daniel A; Cohen, Seth A; Cook, David O; Johnson, L Clifton; Kattner, ShiAnne M; Moore, Carolynn A; Schuster, Micah D; Staudaher, Shawn M

    2010-01-01

    The Wyoming Survey for H-alpha, or WySH, is a large-area, ground-based imaging survey for H-alpha-emitting galaxies at redshifts of z ~ 0.16, 0.24, 0.32, and 0.40. The survey spans up to four square degrees in a set of fields of low Galactic cirrus emission, using twin narrowband filters at each epoch for improved stellar continuum subtraction. H-alpha luminosity functions are presented for each Delta(z) ~ 0.02 epoch based on a total of nearly 1200 galaxies. These data clearly show an evolution with lookback time in the volume-averaged cosmic star formation rate. Integrals of Schechter fits to the incompleteness- and extinction-corrected H-alpha luminosity functions indicate star formation rates per co-moving volume of 0.010, 0.013, 0.020, 0.022 h_70 M_sun yr^{-1} Mpc^{-3} at z ~ 0.16, 0.24, 0.32, and 0.40, respectively. Statistical and systematic measurement uncertainties combined are on the order of 25% while the effects of cosmic variance are at the 20% level. The bulk of this evolution is driven by change...

  8. The nature of nuclear H-alpha emission in LINERs

    OpenAIRE

    Masegosa, J.; Ma?rquez, I.; Ramirez, A.; Gonza?lez-marti?n, O.

    2011-01-01

    To get insight in the nature of the ionized gas in the nuclear region of LINERs we have performed a study of HST Halpha imaging of 32 LINERs. The main conclusion from this analysis is that for the large majority of LINERs (84%) an unresolved nuclear source has been identified as well as extended emission with equivalent sizes ranging from few tens till about hundredths of parsecs. Their morphologies appear not to be homogeneous being basically grouped into three classes:nucl...

  9. A large narrow band H$\\alpha$ survey at $z\\sim0.2$: the bright end of the luminosity function, cosmic variance and clustering across cosmic time

    CERN Document Server

    Stroe, Andra

    2015-01-01

    We carried out the largest ($>3.5\\times10^5$ Mpc$^3$, 26 deg$^2$) H$\\alpha$ narrow band survey to date at $z\\sim0.2$ in the SA22, W2 and XMMLSS extragalactic fields. Our survey covers a large enough volume to overcome cosmic variance and to sample bright and rare H$\\alpha$ emitters up to an observed luminosity of $\\sim10^{42.4}$ erg s$^{-1}$, equivalent to $\\sim11 M_\\odot$ yr$^{-1}$. Using our sample of $220$ sources brighter than $>10^{41.4}$ erg s$^{-1}$ ($>1 M_\\odot$ yr$^{-1}$), we derive H$\\alpha$ luminosity functions, which are well described by a Schechter function with $\\phi^* = 10^{-2.85\\pm0.03}$ Mpc$^{-3}$ and $L^*_{H\\alpha} = 10^{41.71\\pm0.02}$ erg s$^{-1}$ (with a fixed faint end slope $\\alpha=-1.35$). We find that surveys probing smaller volumes ($\\sim3\\times10^4$ Mpc$^3$) are heavily affected by cosmic variance, which can lead to errors of over $100$ per cent in the characteristic density and luminosity of the H$\\alpha$ luminosity function. We derive a star formation rate density of $\\rho_\\mathrm...

  10. Supernova-Driven Outflows in NGC 7552: A Comparison of H-alpha and UV Tracers

    CERN Document Server

    Wood, Corey M; Calzetti, Daniela; Leitherer, Claus; Chisholm, John; Gallagher, John S

    2015-01-01

    We investigate the supernova-driven galactic wind of the barred spiral galaxy NGC 7552, using both ground-based optical nebular emission lines and far-ultraviolet absorption lines measured with the Hubble Space Telescope Cosmic Origins Spectrograph. We detect broad (~300 km/s) blueshifted (-40 km/s) optical emission lines associated with the galaxy's kpc-scale star-forming ring. The broad line kinematics and diagnostic line ratios suggest that the H-alpha emission comes from clouds of high density gas entrained in a turbulent outflow. We compare the H-alpha emission line profile to the UV absorption line profile measured along a coincident sight line and find significant differences. The maximum blueshift of the H-alpha-emitting gas is ~290 km/s, whereas the UV line profile extends to blueshifts upwards of 1000 km/s. The mass outflow rate estimated from the UV is roughly nine times greater than that estimated from H-alpha. We argue that the H-alpha emission traces a cluster-scale outflow of dense, low velocit...

  11. Galaxy And Mass Assembly (GAMA): Bivariate functions of H$\\alpha$ star forming galaxies

    CERN Document Server

    Gunawardhana, M L P; Taylor, E N; Bland-Hawthorn, J; Norberg, P; Baldry, I K; Loveday, J; Owers, M S; Wilkins, S M; Colless, M; Brown, M J I; Driver, S P; Alpaslan, M; Brough, S; Cluver, M; Croom, S; Kelvin, L; Lara-López, M A; Liske, J; López-Sánchez, A R; Robotham, A S G

    2014-01-01

    We present bivariate luminosity and stellar mass functions of H$\\alpha$ star forming galaxies drawn from the Galaxy And Mass Assembly (GAMA) survey. While optically deep spectroscopic observations of GAMA over a wide sky area enable the detection of a large number of $0.001<{SFR}_{H\\alpha}$ (M$_{\\odot}$ yr$^{-1}$)$<100$ galaxies, the requirement for an H$\\alpha$ detection in targets selected from an $r$-band magnitude limited survey leads to an incompleteness due to missing optically faint star forming galaxies. Using $z<0.1$ bivariate distributions as a reference we model the higher-$z$ distributions, thereby approximating a correction for the missing optically faint star forming galaxies to the local SFR and stellar mass densities. Furthermore, we obtain the $r$-band LFs and stellar mass functions of H$\\alpha$ star forming galaxies from the bivariate LFs. As our sample is selected on the basis of detected H$\\alpha$ emission, a direct tracer of on-going star formation, this sample represents a true ...

  12. H-$\\alpha$ Imaging of Early-type(Sa-Sab) Spiral Galaxies, 1

    CERN Document Server

    Hameed, S A; Hameed, Salman; Devereux, Nick

    1999-01-01

    H-alpha and continuum images are presented for 27 nearby early-type(Sa-Sab) spiral galaxies. Contrary to popular perception, the images reveal copious massive star formation in some of these galaxies. A determination of the H-alpha morphology and a measure of the H-alpha luminosity suggests that early-type spirals can be classified into two broad categories based on the luminosity of largest HII region in the disk. The first category includes galaxies for which the individual HII regions have L(H-alpha) 10^(39) erg/s. All category 2 galaxies show either prominent dust lanes or other morphological peculiarities such as tidal tails which suggests that the anomalously luminous HII regions in category 2 galaxies may have formed as a result of a recent interaction. The observations, which are part of an on-going H-alpha survey, reveal early-type spirals to be a heterogeneous class of galaxies that are evolving in the current epoch. We have also identified some systematic differences between the classifications of...

  13. A Dual Narrowband Survey for H\\alpha\\ Emitters at z=2.2: Demonstration of the Technique and Constraints on the H\\alpha\\ Luminosity Function

    CERN Document Server

    Lee, Janice C; Spitler, L; Labbe, I; Salim, S; Persson, S E; Ouchi, M; Dale, D; Monson, A; Murphy, D

    2012-01-01

    We present first results from a narrowband imaging program for intermediate redshift emission-line galaxies using the newly commissioned FourStar infrared camera at the 6.5m Magellan telescope. To enable prompt identification of H\\alpha\\ emitters, a pair of custom 1% filters, which sample low-airglow atmospheric windows at 1.19 \\mu m and 2.10 \\mu m, is used to detect both H\\alpha\\ and [OII]\\lambda 3727 emission from the same redshift volume at z=2.2. Initial observations are taken over a 130 arcmin^2 area in the CANDELS-COSMOS field. The exquisite image quality resulting from the combination of the instrument, telescope, and standard site conditions (~0.55" FWHM) allows the 1.19 \\mu m and 2.10 \\mu m data to probe 3\\sigma\\ emission-line depths down to 1.0e-17 erg/s/cm^2 and 1.2e-17 erg/s/cm^2 respectively, in less than 10 hours of integration time in each narrowband. For H\\alpha\\ at z=0.8 and z=2.2, these fluxes correspond to observed star formation rates of ~0.3 and ~4 Msun/yr respectively. We find 122 source...

  14. The Discovery of a Giant H-alpha Filament in NGC 7213

    CERN Document Server

    Hameed, S A; Young, L; Devereux, N; Hameed, Salman; Blank, David; Young, Lisa; Devereux, Nick

    2000-01-01

    The nearby Seyfert galaxy NGC 7213 has been imaged in H-alpha and HI with the CTIO 1.5 m telescope and with the Australia Telescope Compact Array (ATCA), respectively. Optically NGC 7213 looks undisturbed and relatively featureless but the continuum-subtracted H-alpha image shows a 19 kpc long filament located approximately 18.6 kpc from the nucleus. The H-alpha filament could be neutral gas photo-ionized by the active nucleus, as has been suggested for the Seyfert galaxy NGC 5252, or shock-ionized by a jet interacting with the surrounding HI, as has been suggested for the radio galaxy PKS 2240-41. The HI map reveals NGC 7213 to be a highly disturbed system suggesting a past merging event.

  15. H-alpha Survey of the Local Volume: Isolated Southern Galaxies

    OpenAIRE

    Kaisin, S. S.; Kasparova, A. V.; Knyazev, A. Yu.; Karachentsev, I D

    2007-01-01

    We present our H-alpha observations of 11 isolated southern galaxies: SDIG, PGC 51659, E 222-010, E 272-025, E 137-018, IC 4662, Sag DIG, IC 5052, IC 5152, UGCA 438, and E149-003, with distances from 1 to 7 Mpc. We have determined the total H-alpha fluxes from these galaxies. The star formation rates in these galaxies range from 10^{-1} (IC 4662) to 10^{-4}_{\\odot}/yr (SDIG) and the gas depletion time at the observed star formation rates lies within the range from 1/6 to 24 ...

  16. H-alpha Survey of the Local Volume: Isolated Southern Galaxies

    CERN Document Server

    Kaisin, S S; Knyazev, A Yu; Karachentsev, I D

    2007-01-01

    We present our H-alpha observations of 11 isolated southern galaxies: SDIG, PGC 51659, E 222-010, E 272-025, E 137-018, IC 4662, Sag DIG, IC 5052, IC 5152, UGCA 438, and E149-003, with distances from 1 to 7 Mpc. We have determined the total H-alpha fluxes from these galaxies. The star formation rates in these galaxies range from 10^{-1} (IC 4662) to 10^{-4}_{\\odot}/yr (SDIG) and the gas depletion time at the observed star formation rates lies within the range from 1/6 to 24 Hubble times H_0^{-1} .

  17. First Simultaneous Observation of H-alpha Moreton Wave, EUV Wave, and Filament/Prominence Oscillations

    OpenAIRE

    Asai, Ayumi; Ishii, Takako T.; Isobe, Hiroaki; Kitai, Reizaburo; Ueno, Satoru; Nagata, Shin Ichi; Morita, Satoshi; Nishida, Keisuke; Shiota, Daikou; Oi, Akihito; Akioka, Maki; Shibata, Kazunari

    2011-01-01

    We report on the first simultaneous observation of an H-alpha Moreton wave, the corresponding EUV fast coronal waves, and a slow and bright EUV wave (typical EIT wave). Associated with an X6.9 flare that occurred on 2011 August 9 at the active region NOAA 11263, we observed a Moreton wave in the H-alpha images taken by the Solar Magnetic Activity Research Telescope (SMART) at Hida Observatory of Kyoto University. In the EUV images obtained by the Atmospheric Imaging Assembly...

  18. Observational and theoretical constraints for an H$\\alpha$-halo around the Crab Nebula

    OpenAIRE

    Tziamtzis, A.; Schirmer, M.; Lundqvist, P.; J. Sollerman

    2009-01-01

    We searched for a fast moving H$\\alpha$ shell around the Crab nebula. Such a shell could account for this supernova remnant's missing mass, and carry enough kinetic energy to make SN 1054 a normal Type II event. Deep H$\\alpha$ images were obtained with WFI at the 2.2m MPG/ESO telescope and with MOSCA at the 2.56m NOT. The data are compared with theoretical expectations derived from shell models with ballistic gas motion, constant temperature, constant degree of ionisation an...

  19. The H-alpha Light Curves and Spatial Distribution of Novae in M81

    OpenAIRE

    Neill, James D.; Shara, Michael M.

    2003-01-01

    We present the results of a preliminary H-alpha survey of M81 for novae conducted over a 5 month interval using the 5' field of view camera (WFCAM) on the Calypso Telescope at Kitt Peak, AZ. We observed M81 nearly every clear night during this interval, covering the entire galaxy, and discovered 12 novae. Our comprehensive time coverage allowed us to produce the most complete set of H-alpha light curves for novae in M81 to date. A raw nova rate for M81 gives 23 yr^-1 which, ...

  20. MASH-II: More Planetary Nebulae from the AAO/UKST H\\alpha Survey

    OpenAIRE

    Miszalski, B.; Parker, Q. A.; Acker, A.; Birkby, J. L.; Frew, D. J.; Kovacevic, A.

    2007-01-01

    We present a supplement to the Macquarie/AAO/Strasbourg H$\\alpha$ planetary nebulae (PNe) catalogue (MASH), which we denote MASH-II. The supplement consists of over 300 true, likely and possible new Galactic PNe found after re-examination of the entire AAO/UKST H$\\alpha$ survey of the southern Galactic Plane in digital form. We have spectroscopically confirmed over 240 of these new candidates as bona-fide PNe and we include other high quality candidates awaiting spectroscopi...

  1. Observatons of NGC 3077 Galaxy in Narrow Band [SII] and H_alpha Filters

    OpenAIRE

    Andjelic, M.; Stavrev, K.; Arbutina, B.; Ilic, D.; Urosevic, D.

    2011-01-01

    We present observations of the HI tidal arm near dwarf galaxy NGC 3077 (member of the M81 galaxy group) in narrow band [SII] and H_alpha filters. Observations were carried out in March 2011 with the 2m RCC telescope at NAO Rozhen, Bulgaria. Our search for possible supernova remnant candidates (identified as sources with enhanced [SII] emission relative to their H_alpha emission) in this region yielded no sources of this kind. Nevertheless, we found a number of objects with s...

  2. First Simultaneous Observation of H-alpha Moreton Wave, EUV Wave, and Filament/Prominence Oscillations

    CERN Document Server

    Asai, Ayumi; Isobe, Hiroaki; Kitai, Reizaburo; UeNo, Satoru; Nagata, Shin'ichi; Morita, Satoshi; Nishida, Keisuke; Shiota, Daikou; Oi, Akihito; Akioka, Maki; Shibata, Kazunari

    2011-01-01

    We report on the first simultaneous observation of an H-alpha Moreton wave, the corresponding EUV fast coronal waves, and a slow and bright EUV wave (typical EIT wave). Associated with an X6.9 flare that occurred on 2011 August 9 at the active region NOAA 11263, we observed a Moreton wave in the H-alpha images taken by the Solar Magnetic Activity Research Telescope (SMART) at Hida Observatory of Kyoto University. In the EUV images obtained by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO) we found not only the corresponding EUV fast "bright" coronal wave, but also the EUV fast "faint" wave that is not associated with the H-alpha Moreton wave. We also found a slow EUV wave, which corresponds to a typical EIT wave. Furthermore, we observed, for the first time, the oscillations of a prominence and a filament, simultaneously, both in the H-alpha and EUV images. To trigger the oscillations by the flare-associated coronal disturbance, we expect a coronal wave as fast as the fast...

  3. H$\\alpha$ and Free-Free Emission from the WIM

    CERN Document Server

    Dong, Ruobing

    2010-01-01

    Recent observations have found the ratio of H$\\alpha$ to free-free radio continuum to be surprisingly high in the diffuse ionized ISM (the so-called WIM), corresponding to an electron temperature of only $\\sim$3000~K. Such low temperatures were unexpected in gas that was presumed to be photoionized. We consider a 3-component model for the observed diffuse emission, consisting of a mix of (1) photoionized gas, (2) gas that is recombining and cooling, and (3) cool H~I gas. This model can successfully reproduce the observed intensities of free-free continuum, H$\\alpha$, and collisionally-excited lines such as [\\ion{N}{2}]6583. To reproduce the low observed value of free-free to H$\\alpha$, the PAH abundance in the photoionized regions must be lowered by a factor $\\sim$3, and $\\sim$15\\% of the diffuse H$\\alpha$ must be reflected from dust grains, as suggested by \\citet{Wood+Reynolds_1999}.

  4. Canes Venatici I cloud of galaxies seen in the H-alpha line

    CERN Document Server

    Kaisin, S S

    2007-01-01

    We present results of H-alpha imaging for 42 galaxies in the nearby low-density cloud Canes Venatici I populated mainly by late-type objects. Estimates of the H-alpha flux and integrated star formation rate (SFR) are now available for all 78 known members of this scattered system, spanning a large range in luminosity, surface brightness, HI content and SFR. Distributions of the CVnI galaxies versus their SFR, blue absolute magnitude and total hydrogen mass are given in comparison with those for a population of the nearby virialized group around M81. We found no essential correlation between star formation activity in a galaxy and its density environment. A bulk of CVnI galaxies had enough time to generate their baryon mass with the observed SFR. Most of them possess also a supply of gas sufficient to maintain their observed SFR's during the next Hubble time.

  5. Variations of flaring kernel sizes in various parts of the H-alpha line profile

    CERN Document Server

    Radziszewski, K

    2012-01-01

    We analyze the temporal variations of the sizes and emission intensities of thirtyone flaring kernels in various parts of the H{\\alpha} line profile. We have found that the areas of all kernels decrease systematically when observed in consecutive wavelengths toward the wings of the H{\\alpha} line, but their areas and emission intensity vary in time. Our results are in agreement with the commonly accepted model of the glass-shaped lower parts of the magnetic flaring loops channelling high energy variable particle beams toward the chromospheric plasma. High time resolution spectral-imaging data used in our work were collected using the Large Coronagraph and Horizontal Telescope equipped with the Multi-channel Subtractive Double Pass Spectrograph and the Solar Eclipse Coronal Imaging System (MSDP-SECIS) at the Bia{\\l}k\\'ow Observatory of the University of Wroc{\\l}aw, Poland.

  6. H\\alpha\\ spectroscopy and multiwavelength imaging of a solar flare caused by filament eruption

    OpenAIRE

    Huang, Z.; Madjarska, M. S.; Koleva, K.; Doyle, J. G.; Duchlev, P.; Dechev, M.; Reardon, K.

    2014-01-01

    We study a sequence of eruptive events including filament eruption, a GOES C4.3 flare and a coronal mass ejection. We aim to identify the possible trigger(s) and precursor(s) of the filament destabilisation; investigate flare kernel characteristics; flare ribbons/kernels formation and evolution; study the interrelation of the filament-eruption/flare/coronal-mass-ejection phenomena as part of the integral active-region magnetic field configuration; determine H\\alpha\\ line pro...

  7. Star-formation properties of Hickson Compact Groups based on deep H{\\alpha} imaging

    CERN Document Server

    Eigenthaler, Paul; Verdugo, Miguel; Ziegler, Bodo

    2015-01-01

    We present deep H{\\alpha} imaging of seven Hickson Compact Groups (HCGs) using the 4.1m Southern Astrophysics Research (SOAR) Telescope. The high spatial resolution of the observations allow us to study both the integrated star-formation properties of the main galaxies as well as the 2D distribution of star-forming knots in the faint tidal arms that form during interactions between the individual galaxies. We derive star-formation rates and stellar masses for group members and discuss their position relative to the main sequence of star-forming galaxies. Despite the existence of tidal features within the galaxy groups, we do not find any indication for enhanced star-formation in the selected sample of HCGs. We study azimuthally averaged H{\\alpha} profiles of the galaxy disks and compare them with the g' and r' surface-brightness profiles. We do not find any truncated galaxy disks but reveal that more massive galaxies show a higher light concentration in H{\\alpha} than less massive ones. We also see that galax...

  8. Ultra-deep H-alpha Imaging of Nearby Dwarf Galaxies

    Science.gov (United States)

    Lee, Janice C.

    2015-01-01

    I will present new results on diffuse H-alpha emission in nearby dwarf galaxies. Observations have been obtained with the Magellan Maryland Tunable Filter, and are 8-10 times deeper in surface brightness than previous standard narrowband imaging of local galaxies. The new observations were initially motivated by the finding that the H-alpha flux from dwarf and low surface brightness galaxies systematically under-predicts the star formation rate relative to expectations based on the far ultraviolet flux. While detailed follow-up studies of many of the potential causes of the-lower-than-expected H-alpha fluxes have been performed, the possibility that previous imaging has missed a non-negligible fraction of the diffuse flux has not been addressed. I will show what the new observations reveal, and discuss implications for the measurement of the star formation rate, the propagation of ionizing photons into the halos of dwarf galaxies, and the properties of low-luminosity HII regions.

  9. The H-alpha surface brightness - radius relation: a robust statistical distance indicator for planetary nebulae

    CERN Document Server

    Frew, David J; Bojicic, I S

    2015-01-01

    Measuring the distances to Galactic planetary nebulae (PNe) has been an intractable problem for many decades. We have now established a robust optical statistical distance indicator, the H-alpha surface brightness -radius or S-r relation, which addresses this problem. We developed this relation from a critically evaluated sample of primary calibrating PNe. The robust nature of the method results from our revised calibrating distances with significantly reduced systematic uncertainties, and the recent availability of high-quality data, including updated nebular diameters and integrated H-alpha fluxes. The S-r technique is simple in its application, requiring only an angular size, an integrated H-alpha flux, and the reddening to the PN. From these quantities, an intrinsic radius is calculated, which when combined with the angular size, yields the distance directly. Furthermore, we have found that optically thick PNe tend to populate the upper bound of the trend, while optically-thin PNe fall along the lower bou...

  10. Spatially Resolved Ultraviolet, H-alpha, Infrared, and Radio Star Formation in M81

    CERN Document Server

    Gordon, K D; Appleton, P N; Bendo, G J; Calzetti, D; Dale, D A; Draine, B T; Engelbracht, C W; Frayer, D T; Helou, G; Hines, D C; Hinz, J L; Kelly, D M; Kennicutt, R C; Misselt, K A; Morrison, J E; Murphy, E J; Muzerolle, J; Pérez-González, P G; Regan, M W; Rieke, G H; Smith, J D T; Stansberry, J A; Stolovy, S R; Storrie-Lombardi, L J; Su, K Y L; Thornley, M D; Walter, F; Young, E T

    2004-01-01

    We present Multiband Imaging Photometer for Spitzer (MIPS) observations of M81 at 24, 70, and 160 micron. The grand design nature of M81 is clearly seen, showing two well resolved spiral arms containing numerous bright star forming regions. The MIPS images reveal a significant amount of cold dust associated with the spiral arms. We investigate the variation of the ultraviolet (UV), H-alpha, and infrared (IR) luminosities and star formation rate (SFR) indicators across the face of M81 using the MIPS images and archival UV and H-alpha images. For regions in M81, we find that UV and H-alpha SFRs (uncorrected for dust attenuation) are always lower than the IR SFR. The cause of this behavior is dust attenuation and/or using SFR calibrations appropriate for entire galaxies, not regions in galaxies. The characteristics of the dust attenuation for the regions indicate the dust grains and/or geometry are different from those in starburst galaxies. The behavior of the infrared-radio correlation in M81 is seen to vary f...

  11. H$\\alpha$ Emission From Active Equal-mass, Wide M Dwarf Binaries

    CERN Document Server

    Gunning, Heather C; Davenport, James R A; Dhital, Saurav; Hawley, Suzanne L; West, Andrew A

    2014-01-01

    We identify a sample of near-equal mass wide binary M dwarf systems from the SLoWPoKES catalog of common proper-motion binaries and obtain follow-up observations of their chromospheric activity as measured by the H$\\alpha$ emission line. We present optical spectra for both components of 48 candidate M dwarf binaries, confirming their mid-M spectral types. Of those 48 coeval pairs, we find eight with H$\\alpha$ emission from both components, three with weak emission in one component and no emission in the other, and 37 with two inactive components. We find that of the eleven pairs with at least one active component, only three follow the net trend of decreasing activity strength $L_{\\rm H\\alpha}/L_{\\rm bol}$ with later spectral type. The difference in quiescent activity strength between the A and B components is larger than what would be expected based on the small differences in color (mass). For five binaries with two active components, we present 47 hours of time-resolved spectroscopy, observed on the ARC 3....

  12. The star formation properties of disk galaxies H $\\alpha$ imaging of galaxies in the Coma supercluster

    CERN Document Server

    Gavazzi, G; Carrasco, L; Boselli, A; Contursi, A

    1998-01-01

    We present integrated H alpha measurements obtained from imaging observations of 98 late-type galaxies, primarily selected in the Coma supercluster. These data, combined with H alpha photometry from the literature, include a magnitude selected sample of spiral (Sa to Irr) galaxies belonging to the "Great Wall" complete up to mp=15.4, thus composed of galaxies brighter than Mp=-18.8 (H0=100 km Mpc^-1 s^-1). The frequency distribution of the H alpha E.W., determined for the first time from an optically complete sample, is approximately gaussian peaking at E.W. ~25 A. We find that, at the present limiting luminosity, the star formation properties of spiral+Irr galaxies members of the Coma and A1367 clusters do not differ significantly from those of the isolated ones belonging to the Great Wall. The present analysis confirms the well known increase of the current massive star formation rate (SFR) with Hubble type. Moreover perhaps a more fundamental anticorrelation exists between the SFR and the mass of disk gala...

  13. Mapping High-velocity H-alpha and Lyman-alpha Emission from Supernova 1987A

    CERN Document Server

    France, Kevin; Fransson, Claes; Larsson, Josefin; Frank, Kari A; Burrows, David N; Challis, Peter; Kirshner, Robert P; Chevalier, Roger A; Garnavich, Peter; Heng, Kevin; Lawrence, Stephen S; Lundqvist, Peter; Smith, Nathan; Sonneborn, George

    2015-01-01

    We present new {\\it Hubble Space Telescope} images of high-velocity H-$\\alpha$ and Lyman-$\\alpha$ emission in the outer debris of SN~1987A. The H-$\\alpha$ images are dominated by emission from hydrogen atoms crossing the reverse shock. For the first time we observe emission from the reverse shock surface well above and below the equatorial ring, suggesting a bipolar or conical structure perpendicular to the ring plane. Using the H$\\alpha$ imaging, we measure the mass flux of hydrogen atoms crossing the reverse shock front, in the velocity intervals ($-$7,500~$<$~$V_{obs}$~$<$~$-$2,800 km s$^{-1}$) and (1,000~$<$~$V_{obs}$~$<$~7,500 km s$^{-1}$), $\\dot{M_{H}}$ = 1.2~$\\times$~10$^{-3}$ M$_{\\odot}$ yr$^{-1}$. We also present the first Lyman-$\\alpha$ imaging of the whole remnant and new $Chandra$ X-ray observations. Comparing the spatial distribution of the Lyman-$\\alpha$ and X-ray emission, we observe that the majority of the high-velocity Lyman-$\\alpha$ emission originates interior to the equatorial...

  14. A Spectroscopic Study of the H-alpha Surface Brightness Profiles in the Outer Disks of Galaxies

    CERN Document Server

    Christlein, Daniel; Bland-Hawthorn, Joss

    2010-01-01

    The surface brightness profile of H-alpha emission in galaxies is generally thought to be confined by a sharp truncation, sometimes speculated to coincide with a star formation threshold. Over the past years, observational evidence for both old and young stellar populations, as well as individual H II regions, has demonstrated that the outer disk is an actively evolving part of a galaxy. To provide constraints on the origin of the aforementioned H-alpha truncation and the relation of H-alpha emission in the outer disk to the underlying stellar population, we measure the shape of the outer H-alpha surface brightness profile of 15 isolated, edge-on late-type disk galaxies using deep, long-slit spectroscopy. Tracing H-alpha emission up to 50% beyond the optical radius, R_25, we find a composite H-alpha surface brightness profile, well described by a broken-exponential law, that drops more steeply in the outer disk, but which is not truncated. The stellar continuum and H-alpha surface brightness both exhibit a br...

  15. Optical Observations of M81 Galaxy Group in Narrow Band [SII] and H_alpha Filters: Holmberg IX

    Directory of Open Access Journals (Sweden)

    Arbutina, B.

    2009-12-01

    Full Text Available We present observations of the nearby tidal dwarf galaxy Holmberg IX in M81 galaxy group in narrow band [SII] and H$alpha$ filters, carried out in March and November 2008 with the 2m RCC telescope at NAO Rozhen, Bulgaria. Our search for resident supernova remnants (identified as sources with enhanced [SII] emission relative to their H$alpha$ emission in this galaxy yielded no sources of this kind, besides M&H 10-11 or HoIX X-1. Nevertheless, we found a number of objects with significant H$alpha$ emission that probably represent uncatalogued HII regions.

  16. Optical Observations of M81 Galaxy Group in Narrow Band [SII] and H_alpha Filters: Holmberg IX

    CERN Document Server

    Arbutina, B; Stavrev, K; Urosevic, D; Vukotic, B; Onic, D; 10.2298/SAJ0979087A

    2009-01-01

    We present observations of the nearby tidal dwarf galaxy Holmberg IX in M81 galaxy group in narrow band [SII] and H$\\alpha$ filters, carried out in March and November 2008 with the 2m RCC telescope at NAO Rozhen, Bulgaria. Our search for resident supernova remnants (identified as sources with enhanced [SII] emission relative to their H$\\alpha$ emission) in this galaxy yielded no sources of this kind, besides M&H 10-11 or HoIX X-1. Nevertheless, we found a number of objects with significant H$\\alpha$ emission that probably represent uncatalogued HII regions.

  17. The critical velocity effect as a cause for the H\\alpha emission from the Magellanic stream

    OpenAIRE

    Konz, C.; Lesch, H.; Birk, G. T.; Wiechen, H.

    2000-01-01

    Observations show significant H\\alpha-emissions in the Galactic halo near the edges of cold gas clouds of the Magellanic Stream. The source for the ionization of the cold gas is still a widely open question. In our paper we discuss the critical velocity effect as a possible explanation for the observed H\\alpha-emission. The critical velocity effect can yield a fast ionization of cold gas if this neutral gas passes through a magnetized plasma under suitable conditions. We sho...

  18. HH 666: Different kinematics from H{\\alpha} and [Fe II] emission provide a missing link between jets and outflows

    OpenAIRE

    Reiter, Megan; Smith, Nathan; Kiminki, Megan M.; Bally, John

    2015-01-01

    HH 666 is an externally irradiated protostellar outflow in the Carina Nebula for which we present new near-IR [Fe II] spectra obtained with the FIRE spectrograph at Magellan Observatory. Earlier H{\\alpha} and near-IR [Fe II] imaging revealed that the two emission lines trace substantially different morphologies in the inner ~40" of the outflow. H{\\alpha} traces a broad cocoon that surrounds the collimated [Fe II] jet that extends throughout the parent dust pillar. New spectr...

  19. Real-time flare detection in ground-based H$\\alpha$ imaging at Kanzelh\\"ohe Observatory

    CERN Document Server

    Pötzi, Werner; Riegler, Gernot; Amerstorfer, Ulrike; Pock, Thomas; Temmer, Manuela; Polanec, Wolfgang; Baumgartner, Dietmar J

    2014-01-01

    Kanzelh\\"ohe Observatory (KSO) regularly performs high-cadence full-disk imaging of the solar chromosphere in the H$\\alpha$ and CaIIK spectrallines as well as the solar photosphere in white-light. In the frame of ESA's Space Situational Awareness (SSA) programme, a new system for real-time H$\\alpha$ data provision and automatic flare detection was developed at KSO. The data and events detected are published in near real-time at ESA's SSA Space Weather portal (http://swe.ssa.esa.int/web/guest/kso-federated). In this paper, we describe the H$\\alpha$ instrument, the image recognition algorithms developed, the implementation into the KSO H$\\alpha$ observing system and present the evaluation results of the real-time data provision and flare detection for a period of five months. The H$\\alpha$ data provision worked in $99.96$% of the images, with a mean time lag between image recording and online provision of 4s. Within the given criteria for the automatic image recognition system (at least three H$\\alpha$ images a...

  20. HH 666: Different kinematics from H{\\alpha} and [Fe II] emission provide a missing link between jets and outflows

    CERN Document Server

    Reiter, Megan; Kiminki, Megan M; Bally, John

    2015-01-01

    HH 666 is an externally irradiated protostellar outflow in the Carina Nebula for which we present new near-IR [Fe II] spectra obtained with the FIRE spectrograph at Magellan Observatory. Earlier H{\\alpha} and near-IR [Fe II] imaging revealed that the two emission lines trace substantially different morphologies in the inner ~40" of the outflow. H{\\alpha} traces a broad cocoon that surrounds the collimated [Fe II] jet that extends throughout the parent dust pillar. New spectra show that this discrepancy extends to their kinematics. Near-IR [Fe II] emission traces steady, fast velocities of +/- 200 km/s from the eastern and western limbs of the jet. We compare this to a previously published H{\\alpha} spectrum that reveals a Hubble-flow velocity structure near the jet-driving source. New, second-epoch HST/ACS H{\\alpha} images reveal the lateral spreading of the H{\\alpha} outflow lobe away from the jet axis. H{\\alpha} proper motions also indicate a sudden increase in the mass-loss rate ~1000 yr ago, while steady ...

  1. High time resolution observations of solar H-alpha flares - II. Search for signatures of electron beam heating

    CERN Document Server

    Radziszewski, K; Phillips, K J H

    2011-01-01

    Aims. The H-alpha emission of solar flare kernels and associated hard X-ray (HXR) emission often show similar time variations but their light curves are shifted in time by energy transfer mechanisms. We searched for fast radiative response of the chromosphere in the H-alpha line as a signature of electron beam heating. Methods. We investigate the time differences with sub-second resolution between the H-alpha line emission observed with a Multi-channel Subtractive Double Pass (MSDP) spectrograph on the Large Coronagraph and Horizontal Telescope at Bialkow Observatory, Poland, and HXR emission recorded by the RHESSI spacecraft during several flares, greatly extending our earlier analysis (Paper I) to flares between 2003 and 2005. Results. For 16 H-alpha flaring kernels, observed in 12 solar flares, we made 72 measurements of time delays between local maxima of the RHESSI X-ray and H-alpha emissions. For most kernels, there is an excellent correlation between time variations in the H-alpha line emission (at lin...

  2. H-alpha and Free-Free Emission from the WIM

    OpenAIRE

    Dong, Ruobing; Draine, B. T.

    2010-01-01

    Recent observations have found the ratio of H-alpha to free-free radio continuum to be surprisingly high in the diffuse ionized ISM (the so-called WIM), corresponding to an electron temperature of only ~3000K. Such low temperatures were unexpected in gas that was presumed to be photoionized. We consider a 3-component model for the observed diffuse emission, consisting of a mix of (1) photoionized gas, (2) gas that is recombining and cooling, and (3) cool H I gas. This model ...

  3. Orientation of the linear polarization plane of H-alpha emission in prominences

    CERN Document Server

    Suyunova, E Z; Osokin, A R

    2015-01-01

    2D distributions of deviations of the polarization plane from the direction tangential to the solar limb (angle \\chi) and the sign of \\chi are presented for H{\\alpha} prominences of March 29, 2006. The obtained values of \\chi are in agreement with non-eclipse coronagraphic measurements and indicate the existence of longitudinal magnetic fields. The 2D distributions of the sign of \\chi show the existence of both {\\guillemotleft}+{\\guillemotright} and {\\guillemotleft}-{\\guillemotright} polarities for each prominence. An interpretation in the frame of the existence of oppositely directed magnetic fields is noted.

  4. Five WC9 stars discovered in the AAO/UKST H alpha survey

    OpenAIRE

    Hopewell, EC; Barlow, MJ; Drew, JE; Unruh, YC; Parker, QA; Pierce, MJ; Crowther, PA; C. Knigge; Phillipps, S.; Zijlstra, AA

    2005-01-01

    We report the discovery of 5 massive Wolf-Rayet (WR) stars resulting from a programme of follow-up spectroscopy of candidate emission line stars in the AAO/UKST Southern Galactic Plane H-alpha survey. The 6195-6775 angstrom spectra of the stars are presented and discussed. A WC9 class is assigned to all 5 stars through comparison of their spectra with those of known late-type WC stars, bringing the known total number of Galactic WC9 stars to 44. Whilst three of the five WC9 ...

  5. Approximate formulation of redistribution in the Ly-alpha, Ly-beta, H-alpha system

    Science.gov (United States)

    Cooper, J.; Ballagh, R. J.; Hubeny, I.

    1989-01-01

    Simple approximate formulas are given for the coupled redistribution of Ly-alpha, Ly-beta, and H-alpha, by using well-defined approximations to an essentially exact formulation. These formulas incorporate all the essential physics including Raman scattering, lower state radiative decay, and correlated terms representing emission during a collision which must be retained in order that the emission coefficients are properly behaved in the line wings. Approximate expressions for the appropriate line broadening parameters are collected. Finally, practical expressions for the source functions are given. These are formulated through newly introduced nonimpact redistribution functions, which are shown to be reasonably approximated by existing (ordinary and generalized) redistribution functions.

  6. GH $\\alpha$ FaS : Galaxy H-alpha Fabry-Perot System for the WHT

    OpenAIRE

    Hernandez, O; Fathi, K.; Carignan, C.; Beckman, J.; Gach, J. -L.; Balard, P.; Amram, P.; Boulesteix, J.; Corradi, R. L. M; de Denus-Baillargeon, M-M.; Epinat, B.; Relaño, M.; Thibault, S; Vallée, P.

    2008-01-01

    GH$\\alpha$FaS a new Fabry-Perot system, is now available at the William Herschel Telescope. It was mounted, for the first time, at the Nasmyth focus of the 4.2 meter WHT on La Palma in July 2007. Using modern technology, with a spectral resolution of the order R$\\sim$15000, and with a seeing limited spatial resolution, GH$\\alpha$FaS will provide a new look at the H$\\alpha$ -emitting gas over a 4.8 arcminutes circular field in the nearby universe. Many science programs can be...

  7. Analysis of EUV, UV, and H-alpha Emission from Two Very Different Prominences

    Science.gov (United States)

    Kucera, T.; Landi, E.

    2008-01-01

    We analyze the properties of a pair of prominences observed the UV and EUV in April 2004. One was a generally quiet prominence which exhibited a period of activation. Another was a large "coronal cloud" type prominence. Both were observed by SOHO/SUMER, TRACE, and in H$\\alpha$ by BBSO and MLSO. The quiet prominence was also observed by the SOHO/CDS instrument. TRACE and H$\\alpha$ data provide 2D images on with time cadences on the order of 1 minute. The SUMER data was taken from a single slit location with a 90 second cadence and included a number of lines spanning the temperature range 80,000 to 1.6 million K. This observing program was designed to allow us to study prominence dynamics . CDS raster data was taken with a slower cadence, in lines formed at temperatures from 20,000 - 1 million K. We combine these different data sets to analyze the thermal properties, including differential emission measures (DEMs), of these very different prominences, and compare the results to those of prominences previously analyzed by ourselves and others.

  8. The H-alpha Light Curves and Spatial Distribution of Novae in M81

    CERN Document Server

    Neill, J D; Neill, James D.; Shara, Michael M.

    2003-01-01

    We present the results of a preliminary H-alpha survey of M81 for novae conducted over a 5 month interval using the 5' field of view camera (WFCAM) on the Calypso Telescope at Kitt Peak, AZ. We observed M81 nearly every clear night during this interval, covering the entire galaxy, and discovered 12 novae. Our comprehensive time coverage allowed us to produce the most complete set of H-alpha light curves for novae in M81 to date. A raw nova rate for M81 gives 29 yr^-1 which, because of the nature of our survey, is a hard lower limit. An analysis of the completeness in our survey gives a corrected nova rate of 39 yr^-1. This agrees statistically with the rate of 33 (+13,-8) yr^-1, derived from Monte Carlo simulations using nova light curves and survey frame limits. The spatial distribution of the novae we discovered follows the bulge light much better than the disk or total light according to Kolmogorov - Smirnov tests of their radial distributions. The asymmetry in the distribution of novae across the major ax...

  9. Shocks and Star Formation in Stephan's Quintet. I. Gemini Spectroscopy of H{\\alpha}-bright knots

    CERN Document Server

    Konstantopoulos, I S; Guillard, P; Trancho, G; Cluver, M E; Bastian, N; Charlton, J C; Fedotov, K; Gallagher, S C; Smith, L J; Struck, C J

    2013-01-01

    We present a Gemini-GMOS spectroscopic study of HST-selected H{\\alpha}-emitting regions in Stephan's Quintet (HCG 92), a nearby compact galaxy group, with the aim of disentangling the processes of shock-induced heating and star formation in its intra-group medium. The $\\approx$40 sources are distributed across the system, but most densely concentrated in the $\\sim$kpc-long shock region. Their spectra neatly divide them into narrow- and and broad-line emitters, and we decompose the latter into three or more emission peaks corresponding to spatial elements discernible in HST imaging. The emission line ratios of the two populations of H{\\alpha}-emitters confirm their nature as H II regions (90% of the sample) or molecular gas heated by a shock-front propagating at $\\lesssim$300 km/s. Their redshift distribution reveals interesting three-dimensional structure with respect to gas-phase baryons, with no H II regions associated with shocked gas, no shocked regions in the intruder galaxy NGC 7318B, and a sharp bounda...

  10. H{\\alpha} Kinematics of S4G spiral galaxies I. NGC 864

    CERN Document Server

    Erroz-Ferrer, Santiago; Font, Joan; Beckman, John E; Falcón-Barroso, Jesús; Sánchez-Gallego, José Ramón; Athanassoula, E; Bosma, Albert; Gadotti, Dimitri A; Muñoz-Mateos, Juan Carlos; Sheth, Kartik; Buta, Ronald J; Comerón, Sébastien; de Paz, Armando Gil; Hinz, Joannah L; Ho, Luis C; Kim, Taehyun; Laine, Jarkko; Laurikainen, Eija; Madore, Barry F; Menéndez-Delmestre, Karín; Mizusawa, Trisha; Regan, Michael W; Salo, Heikki; Seibert, Mark

    2012-01-01

    We present a study of the kinematics of the isolated spiral galaxy NGC 864, using H{\\alpha} Fabry-Perot data obtained with the GH{\\alpha}FaS instrument at the William Herschel Telescope in La Palma, complemented with images at 3.6 {\\mu}m, in the R band and in H{\\alpha} filter, and integral field spectroscopic data. The resulting data cubes and velocity maps allow the study of the kinematics of the galaxy, including in-depth investigations of the rotation curve, velocity moment maps, velocity residual maps, gradient maps and position-velocity diagrams. We find asymmetries in the velocity field in the bar zone, caused by non-circular motions, probably in response to the potential of the bar. We also find a flat-profile bar, in agreement with the strong bar, with the grand design spiral pattern, and with the gap between the ends of the bar and the start of the spiral arms. We quantify the rate of massive star formation, which is concentrated in the two spiral arms.

  11. Collisionally excited filaments in HST H$\\alpha$ and H$\\beta$ images of HH~1/2

    CERN Document Server

    Raga, A C; Castellanos-Ramírez, A; Chiang, Hsin-Fang; Bally, J

    2014-01-01

    We present new H$\\alpha$ and H$\\beta$ images of the HH~1/2 system, and we find that the H$\\alpha$/H$\\beta$ ratio has high values in ridges along the leading edges of the HH~1 bow shock and of the brighter condensations of HH~2. These ridges have H$\\alpha$/H$\\beta=4\\to 6$, which is consistent with collisional excitation from the $n=1$ to the $n=3$ and 4 levels of hydrogen in a gas of temperatures $T=1.5\\to 10\\times 10^4$~K. This is therefore the first direct proof that the collisional excitation/ionization region of hydrogen right behind Herbig-Haro shock fronts is detected.

  12. A comparison of H-alpha intensity and radio wave scattering on eight low-latitude lines of sight

    Science.gov (United States)

    Spangler, Steven R.; Reynolds, Ronald J.

    1990-01-01

    Radio scattering and H-alpha measurements for eight sources in Cygnus are compared. The diameter of the radio scattering disk at 1 GHz is found to be correlated with emission measure as determined from the H-alpha measurements, and that strong radio scattering characterized by a diameter of about 30 milliarcsec is produced in regions with emission measures of about 100/cm exp 6 pc or less. The slope of diameter-emission measure correlation is steeper than would be the case if all lines of sight were characterized by the same turbulent outer scale and modulation index. It is suggested that the lines of sight to unscattered or lightly scattered sources traverse only a diffuse medium which is revealed by H-alpha observations at high latitudes. Heavily scattered sources are viewed through an additional component of interstellar H II which has turbulence with different properties.

  13. An atlas of H-alpha-emitting regions in M33: A systematic search for SS433 star candidates

    Science.gov (United States)

    Calzetti, Daniela; Kinney, Anne L.; Ford, Holland; Doggett, Jesse; Long, Knox S.

    1995-01-01

    We report finding charts and accurate positions for 432 compact H-alpha emitting regions in the Local Group galaxy M 33 (NGC 598), in an effort to isolate candidates for an SS433-like stellar system. The objects were extracted from narrow band images, centered in the rest-frame H-alpha (lambda 6563 A) and in the red continuum at 6100 A. The atlas is complete down to V approximately equal to 20 and includes 279 compact HII regions and 153 line emitting point-like sources. The point-like sources undoubtedly include a variety of objects: very small HII regions, early type stars with intense stellar winds, and Wolf-Rayet stars, but should also contain objects with the characteristics of SS433. This extensive survey of compact H-alpha regions in M 33 is a first step towards the identification of peculiar stellar systems like SS433 in external galaxies.

  14. High Resolution H alpha Images of the Binary Low-mass Proplyd LV 1 with the Magellan AO System

    CERN Document Server

    Wu, Y -L; Males, J R; Follette, K; Morzinski, K; Kopon, D; Rodigas, T J; Hinz, P; Puglisi, A; Esposito, S; Pinna, E; Riccardi, A; Xompero, M; Briguglio, R

    2013-01-01

    We utilize the new Magellan adaptive optics system (MagAO) to image the binary proplyd LV 1 in the Orion Trapezium at H alpha. This is among the first AO results in visible wavelengths. The H alpha image clearly shows the ionization fronts, the interproplyd shell, and the cometary tails. Our astrometric measurements find no significant relative motion between components over ~18 yr, implying that LV 1 is a low-mass system. We also analyze Large Binocular Telescope AO observations, and find a point source which may be the embedded protostar's photosphere in the continuum. Converting the H magnitudes to mass, we show that the LV 1 binary may consist of one very-low-mass star with a likely brown dwarf secondary, or even plausibly a double brown dwarf. Finally, the magnetopause of the minor proplyd is estimated to have a radius of 110 AU, consistent with the location of the bow shock seen in H alpha.

  15. Prominence and Cool Loop Energetics Measured in the UV, EUV, and H-alpha

    Science.gov (United States)

    Kucera, Therese A.; Landi, E.

    2006-01-01

    We investigate the thermal and dynamic properties of moving features in a prominence jet, a approx. 10(exp 5)K loop near a prominence channel, and an erupting prominence. In order to make measurements of the quickly moving features seen in prominences in the UV we use the SOHO/SUMER spectrograph to take a time series of exposures from a single pointing position, providing a measurement of spectral line properties as a function of time and position along the slit. The lines observed cover a broad range of temperatures from 80,000 - 1.6 million K. These measurements are combined with TRACE movies in transition region and coronal temperature bands and with ground based H-alpha data to obtain more complete information concerning prominence structure and motions. The resulting observations allow us perform DEM analysis and to calculate limits on densities, pressures, and the thermal and kinetic energies of the moving sources.

  16. Magnetic fields of active galactic nuclei and quasars with polarized broad H-alpha lines

    CERN Document Server

    Silant'ev, N A; Buliga, S D; Piotrovich, M Yu; Natsvlishvili, T M

    2012-01-01

    We present estimates of magnetic field in a number of AGNs from the Spectropolarimetric atlas of Smith, Young & Robinson (2002) from the observed degrees of linear polarization and the positional angles of spectral lines (H-alpha) (broad line regions of AGNs) and nearby continuum. The observed polarization is lower than the Milne value in a non-magnetized atmosphere. We hypothesize that the polarized radiation escapes from optically thick magnetized accretion discs and is weakened by the Faraday rotation effect. This effect is able to explain both the value of the polarization and the position angle. We estimate the required magnetic field in the broad line region by using simple asymptotic analytical formulas for Milne's problem in magnetized atmosphere, which take into account the last scattering of radiation before escaping from the accretion disc. The polarization of a broad spectral line escaping from disc is described by the same mechanism. The characteristic features of polarization of a broad line...

  17. The Wyoming Survey for H-alpha. I. Initial Results at z ~ 0.16 and 0.24

    OpenAIRE

    Dale, Daniel A.; Barlow, Rebecca J.; Cohen, Seth A.; Johnson, L. Clifton; Kattner, Shianne M.; Lamanna, Christine A.; Moore, Carolynn A.; Schuster, Micah D.; Thatcher, Jacob W.

    2008-01-01

    The Wyoming Survey for H-alpha, or WySH, is a large-area, ground-based, narrowband imaging survey for H-alpha-emitting galaxies over the latter half of the age of the Universe. The survey spans several square degrees in a set of fields of low Galactic cirrus emission. The observing program focuses on multiple dz~0.02 epochs from z~0.16 to z~0.81 down to a uniform (continuum+line) luminosity at each epoch of ~10^33 W uncorrected for extinction (3sigma for a 3" diameter apertu...

  18. The critical velocity effect as a cause for the H\\alpha emission from the Magellanic stream

    CERN Document Server

    Konz, C; Birk, G T; Wiechen, H

    2001-01-01

    Observations show significant H\\alpha-emissions in the Galactic halo near the edges of cold gas clouds of the Magellanic Stream. The source for the ionization of the cold gas is still a widely open question. In our paper we discuss the critical velocity effect as a possible explanation for the observed H\\alpha-emission. The critical velocity effect can yield a fast ionization of cold gas if this neutral gas passes through a magnetized plasma under suitable conditions. We show that for parameters that are typical for the Magellanic Stream the critical velocity effect has to be considered as a possible ionization source of high relevance.

  19. Optical observations of the nearby galaxy IC342 with narrow band [SII] and H$\\alpha$ filters. I

    CERN Document Server

    Vucetic, M M; Urosevic, D; Dobardzic, A; Pavlovic, M Z; Pannuti, T G; Petrov, N

    2013-01-01

    We present observations of the portion of the nearby spiral galaxy IC342 using narrow band [SII] and H$\\alpha$ filters. These observations were carried out in November 2011 with the 2m RCC telescope at Rozhen National Astronomical Observatory in Bulgaria. In this paper we report coordinates, diameters, H$\\alpha$ and [SII] fluxes for 203 HII regions detected in two fields of view in IC342 galaxy. The number of detected HII regions is 2.5 times higher than previously known in these two parts of the galaxy.

  20. Optical observations of the nearby galaxy IC342 with narrow band [SII] and H$\\alpha$ filters. I

    OpenAIRE

    Vucetic, M. M.; Arbutina, B.; Urosevic, D.; Dobardzic, A.; Pavlovic, M. Z.; Pannuti, T. G.; Petrov, N.

    2013-01-01

    We present observations of the portion of the nearby spiral galaxy IC342 using narrow band [SII] and H$\\alpha$ filters. These observations were carried out in November 2011 with the 2m RCC telescope at Rozhen National Astronomical Observatory in Bulgaria. In this paper we report coordinates, diameters, H$\\alpha$ and [SII] fluxes for 203 HII regions detected in two fields of view in IC342 galaxy. The number of detected HII regions is 5 times higher than previously known in th...

  1. Optical Observations of M81 Galaxy Group in Narrow Band [SII] and H_alpha Filters: Holmberg IX

    OpenAIRE

    Arbutina, B.; Ilic?, D.; Stavrev, K.; Uros?evic?, D.; Vukotic?, B.; Onic?, D.

    2009-01-01

    We present observations of the nearby tidal dwarf galaxy Holmberg IX in M81 galaxy group in narrow band [SII] and H$\\alpha$ filters, carried out in March and November 2008 with the 2m RCC telescope at NAO Rozhen, Bulgaria. Our search for resident supernova remnants (identified as sources with enhanced [SII] emission relative to their H$\\alpha$ emission) in this galaxy yielded no sources of this kind, besides M&H 10-11 or HoIX X-1. Nevertheless, we found a number of objects w...

  2. Morita Equivalence

    CERN Document Server

    Barrett, Thomas William

    2015-01-01

    Logicians and philosophers of science have proposed various formal criteria for theoretical equivalence. In this paper, we examine two such proposals: definitional equivalence and categorical equivalence. In order to show precisely how these two well-known criteria are related to one another, we investigate an intermediate criterion called Morita equivalence.

  3. FIRST SIMULTANEOUS OBSERVATION OF AN H{alpha} MORETON WAVE, EUV WAVE, AND FILAMENT/PROMINENCE OSCILLATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Asai, Ayumi; Isobe, Hiroaki [Unit of Synergetic Studies for Space, Kyoto University, Yamashina, Kyoto 607-8471 (Japan); Ishii, Takako T.; Kitai, Reizaburo; Ichimoto, Kiyoshi; UeNo, Satoru; Nagata, Shin' ichi; Morita, Satoshi; Nishida, Keisuke; Shibata, Kazunari [Kwasan and Hida Observatories, Kyoto University, Yamashina, Kyoto 607-8471 (Japan); Shiota, Daikou [Advanced Science Institute, RIKEN, Wako, Saitama 351-0198 (Japan); Oi, Akihito [College of Science, Ibaraki University, Mito, Ibaraki 310-8512 (Japan); Akioka, Maki, E-mail: asai@kwasan.kyoto-u.ac.jp [Hiraiso Solar Observatory, National Institute of Information and Communications Technology, Hitachinaka, Ibaraki 311-1202 (Japan)

    2012-02-15

    We report on the first simultaneous observation of an H{alpha} Moreton wave, the corresponding EUV fast coronal waves, and a slow and bright EUV wave (typical EIT wave). We observed a Moreton wave, associated with an X6.9 flare that occurred on 2011 August 9 at the active region NOAA 11263, in the H{alpha} images taken by the Solar Magnetic Activity Research Telescope at Hida Observatory of Kyoto University. In the EUV images obtained by the Atmospheric Imaging Assembly on board the Solar Dynamic Observatory we found not only the corresponding EUV fast 'bright' coronal wave, but also the EUV fast 'faint' wave that is not associated with the H{alpha} Moreton wave. We also found a slow EUV wave, which corresponds to a typical EIT wave. Furthermore, we observed, for the first time, the oscillations of a prominence and a filament, simultaneously, both in the H{alpha} and EUV images. To trigger the oscillations by the flare-associated coronal disturbance, we expect a coronal wave as fast as the fast-mode MHD wave with the velocity of about 570-800 km s{sup -1}. These velocities are consistent with those of the observed Moreton wave and the EUV fast coronal wave.

  4. Investigating H$\\alpha$, UV, and IR star-formation rate diagnostics for a large sample of z ~ 2 galaxies

    CERN Document Server

    Shivaei, Irene; Steidel, Charles C; Shapley, Alice E

    2015-01-01

    We use a sample of 262 spectroscopically confirmed star-forming galaxies at redshifts $2.08\\leq z\\leq 2.51$ to compare H$\\alpha$, UV, and IR star-formation-rate diagnostics and to investigate the dust properties of the galaxies. At these redshifts, the H$\\alpha$ line shifts to the $K_{s}$-band. By comparing $K_{s}$-band photometry to underlying stellar population model fits to other UV, optical, and near-infrared data, we infer the H$\\alpha$ flux for each galaxy. We obtain the best agreement between H$\\alpha$- and UV-based SFRs if we assume that the ionized gas and stellar continuum are reddened by the same value and that the Calzetti attenuation curve is applied to both. Aided with MIPS 24$\\mu$m data, we find that an attenuation curve steeper than the Calzetti curve is needed to reproduce the observed IR/UV ratios of galaxies younger than 100 Myr. Furthermore, using the bolometric star-formation rate inferred from the UV and mid-IR data (SFR$_{IR}$+SFR$_{UV}$), we calculated the conversion between the H$\\alp...

  5. Development of a high-speed H-alpha camera system for the observation of rapid fluctuations in solar flares

    International Nuclear Information System (INIS)

    A solid-state digital camera was developed for obtaining H alpha images of solar flares with 0.1 s time resolution. Beginning in the summer of 1988, this system will be operated in conjunction with SMM's hard X-ray burst spectrometer (HXRBS). Important electron time-of-flight effects that are crucial for determining the flare energy release processes should be detectable with these combined H alpha and hard X-ray observations. Charge-injection device (CID) cameras provide 128 x 128 pixel images simultaneously in the H alpha blue wing, line center, and red wing, or other wavelength of interest. The data recording system employs a microprocessor-controlled, electronic interface between each camera and a digital processor board that encodes the data into a serial bitstream for continuous recording by a standard video cassette recorder. Only a small fraction of the data will be permanently archived through utilization of a direct memory access interface onto a VAX-750 computer. In addition to correlations with hard X-ray data, observations from the high speed H alpha camera will also be correlated and optical and microwave data and data from future MAX 1991 campaigns. Whether the recorded optical flashes are simultaneous with X-ray peaks to within 0.1 s, are delayed by tenths of seconds or are even undetectable, the results will have implications on the validity of both thermal and nonthermal models of hard X-ray production

  6. Dust-Corrected Star Formation Rates of Galaxies. I. Combinations of H-alpha and Infrared Tracers

    CERN Document Server

    Kennicutt, Robert C Jr; Calzetti, Daniela; Moustakas, John; Dale, Daniel A; Bendo, George; Engelbracht, Charles W; Johnson, Benjamin D; Lee, Janice C

    2009-01-01

    We combine H-alpha emission-line and infrared continuum measurements of two samples of nearby galaxies to derive dust attenuation-corrected star formation rates (SFRs). We use a simple energy balance based method that has been applied previously to HII regions in the Spitzer Infrared Nearby Galaxies Survey (SINGS), and extend the methodology to integrated measurements of galaxies. We find that our composite H-alpha+IR based SFRs are in excellent agreement with attenuation-corrected SFRs derived from integrated spectrophotometry, over the full range of SFRs (0.01 -- 80 solar mass per year) and attenuations (0 -- 2.5 mag) studied. We find that the combination of H-alpha and total infrared luminosities provides the most robust SFR measurements, but combinations of H-alpha measurements with monochromatic luminosities at 24 micron and 8 micron perform nearly as well. The calibrations differ significantly from those obtained for HII regions (Calzetti et al. 2007), with the difference attributable to a more evolved ...

  7. H-alpha survey of low-mass satellites of the neighbouring galaxies M31 and M81

    CERN Document Server

    Kaisin, S S

    2013-01-01

    Images have been obtained at the 6-m telescope at the Special Astrophysical Observatory (SAO) of the Russian Academy of Sciences in the H-alpha line and in the continuum for 20 dwarf spheroidal satellites of M31: And XI-And XXX, plus the distant Globular cluster Bol 520. Their star formation rates (FR) are estimated using the H-alpha flux and the ultraviolet FUV flux measured with the GALEX space telescope. Most of the dSph satellites of M31 have extremely low star formation rates with a characteristic upper limit of SFR~5x10^{-7}. We have made similar estimates of SFR from the H-alpha and FUV fluxes for 13 galaxies with low surface brightness recently discovered in the neighborhood of M81. Eleven of them are physical satellites of M81 with typical SFR< 5x10^{-5}. The median stellar masses of these satellites of M31 and M81 are 0.9 and 1.9 million solar masses, respectively. Our H-alpha observations place a 2-3 times stricter limit on the value of SFR than the data from the GALEX satellite, with a substant...

  8. Strong H-alpha Emission Detected in the M33 Nova Candidate PNV J01340288+3035111

    Science.gov (United States)

    Hornoch, K.; Vaduvescu, O.; Tudor, V.

    2014-07-01

    We obtained four 240-s narrow-band H-alpha and four 120-s R-band CCD frames of M33 on 2014 July 29.206 and 29.222 UT, respectively, with the 2.5-m Isaac Newton Telescope (INT) + WFC at La Palma under ~1.1" seeing.

  9. Detection of H-alpha emission from z>3.5 submillimetre luminous galaxies with AKARI-FUHYU spectroscopy

    CERN Document Server

    Sedgwick, Chris; Pearson, Chris; Smail, Ian; Im, Myungshin; Oyabu, Shinki; Takagi, Toshinobu; Matsuhara, Hideo; Wada, Takehiko; Lee, Hyung Mok; Jeong, Woong-Seob; White, Glenn J

    2013-01-01

    We present tentative H-alpha emission line detections of four submillimetre-detected galaxies at z>3.5: the radio galaxies 8C1909+722 and 4C60.07 at signal-to-noise ratios (SNRs) of 3.1 and 2.5, and two submillimetre-selected galaxies (SMGs) near the first of these at SNRs of 10.0 and 2.4, made with the AKARI Space Telescope as part of the FUHYU mission program. These are the highest-redshift H-alpha detections in such galaxies, made possible by AKARI's unique near-infrared spectroscopic capability. The two radio galaxies had known redshifts and surrounding structure, and we have detected broad H-alpha components indicating the presence of dust-shrouded quasars. We conclude that powerful AGNs at z>3.5 occur in peaks of the star-formation density fields, supporting a close connection between stellar mass build-up and black hole mass assembly at this redshift. We also show that 4C60.07 is a binary AGN. The H-alpha detections of the two SMGs are the first redshift determinations for these sources, confirming the...

  10. Comparison of H-alpha synoptic charts with the large-scale solar magnetic field as observed at Stanford

    Science.gov (United States)

    Duvall, T. L., Jr.; Wilcox, J. M.; Svalgaard, L.; Scherrer, P. H.; Mcintosh, P. S.

    1977-01-01

    Two methods of observing the neutral line of the large-scale photospheric magnetic field are compared: neutral line positions inferred from H-alpha photographs (McIntosh and Nolte, 1975) and observations of the photospheric magnetic field made with low spatial resolution (three minutes) and high sensitivity using the Stanford magnetograph. The comparison is found to be very favorable.

  11. H$\\alpha$ spectroscopy and multi-wavelength imaging of a solar flare caused by filament eruption

    CERN Document Server

    Huang, Z; Koleva, K; Doyle, J G; Duchlev, P; Dechev, M; Reardon, K

    2014-01-01

    We study a sequence of eruptive events including filament eruption, a GOES C4.3 flare and a coronal mass ejection. We aim to identify the possible trigger(s) and precursor(s) of the filament destabilisation; investigate flare kernel characteristics; flare ribbons/kernels formation and evolution; study the interrelation of the filament-eruption/flare/coronal-mass-ejection phenomena as part of the integral active-region magnetic field configuration; determine H alpha line profile evolution during the eruptive phenomena. Multi-instrument observations are analysed including H$\\alpha$ line profiles, speckle images at H$\\alpha$-0.8 \\AA\\ and H$\\alpha$+0.8 \\AA\\ from IBIS at DST/NSO, EUV images and magnetograms from the SDO, coronagraph images from STEREO and the X-ray flux observations from FERMI and GOES. We establish that the filament destabilisation and eruption are the main trigger for the flaring activity. A surge-like event with a circular ribbon in one of the filament footpoints is determined as the possible t...

  12. Comparison of H-alpha and UV Star Formation Rates in the Local Volume: Systematic Discrepancies for Dwarf Galaxies

    CERN Document Server

    Lee, Janice C; Tremonti, Christy; Kennicutt, Robert C; Salim, Samir; Bothwell, Matthew; Calzetti, Daniela; Dalcanton, Julianne; Dale, Daniel; Engelbracht, Chad; J., Jose G Funes S; Johnson, Benjamin; Sakai, Shoko; Skillman, Evan; van Zee, Liese; Walter, Fabian; Weisz, Daniel

    2009-01-01

    (abridged) Using a complete sample of ~300 star-forming galaxies within 11 Mpc, we evaluate the consistency between star formation rates (SFRs) inferred from the far ultraviolet (FUV) non-ionizing continuum and H-alpha nebular emission, assuming standard conversion recipes in which the SFR scales linearly with luminosity at a given wavelength. Our analysis probes SFRs over 5 orders of magnitude, down to ultra-low activities on the order of ~0.0001 M_sun/yr. The data are drawn from the 11 Mpc H-alpha and Ultraviolet Galaxy Survey (11HUGS), which has obtained H-alpha fluxes from ground-based narrowband imaging, and UV fluxes from imaging with GALEX. For normal spiral galaxies (SFR~1 M_sun/yr), our results are consistent with previous work which has shown that FUV SFRs tend to be lower than H-alpha SFRs before accounting for internal dust attenuation, but that there is relative consistency between the two tracers after proper corrections are applied. However, a puzzle is encountered at the faint end of the lumin...

  13. Discovery of H-alpha Emission from the Close Companion Inside the Gap of Transitional Disk HD142527

    CERN Document Server

    Close, L M; Males, J R; Puglisi, A; Xompero, M; Apai, D; Najita, J; Weinberger, A J; Morzinski, K; Rodigas, T J; Hinz, P; Bailey, V; Briguglio, R

    2014-01-01

    We utilized the new high-order 585 actuator Magellan Adaptive Optics system (MagAO) to obtain very high-resolution visible light images of HD142527 with MagAO's VisAO science camera. In the median seeing conditions of the 6.5m Magellan telescope (0.5-0.7"), we find MagAO delivers 24-19% Strehl at H-alpha (0.656 microns). We detect a faint companion (HD142527B) embedded in this young transitional disk system at just 86.3+/-1.9 mas (~12 AU) from the star. The companion is detected in both H-alpha and a continuum filter (Delta_mag=6.33+/-0.20 mag at H-alpha and 7.50+/-0.25 mag in the continuum filter). This provides confirmation of the tentative companion discovered by Biller and co-workers with sparse aperture masking at the 8m VLT. The H-alpha emission from the ~0.25 solar mass companion (EW=180 Angstroms) implies a mass accretion rate of ~5.9x10^-10 Msun/yr, and a total accretion luminosity of 1.2% Lsun. Assuming a similar accretion rate, we estimate that a 1 Jupiter mass gas giant could have considerably bet...

  14. The H$\\alpha$ kinematics of interacting galaxies in 12 compact groups

    CERN Document Server

    Torres-Flores, S; de Oliveira, C Mendes; Plana, H; Balkowski, C; Marcelin, M; Olave-Rojas, D

    2014-01-01

    We present new Fabry-Perot observations for a sample of 42 galaxies located in twelve compact groups of galaxies: HCG 1, HCG 14, HCG 25, HCG 44, HCG 53, HCG 57, HCG 61, HCG 69, HCG 93, VV 304, LGG 455 and Arp 314. From the 42 observed galaxies, a total of 26 objects are spiral galaxies, which range from Sa to Im morphological types. The remaining 16 objects are E, S0 and S0a galaxies. Using these observations, we have derived velocity maps, monochromatic and velocity dispersion maps for 24 galaxies, where 18 are spiral, three are S0a, two are S0 and one is an Im galaxy. From the 24 velocity fields obtained, we could derive rotation curves for 15 galaxies; only two of them exhibit rotation curves without any clear signature of interactions. Based on kinematic information, we have evaluated the evolutionary stage of the different groups of the current sample. We identify groups that range from having no H$\\alpha$ emission to displaying an extremely complex kinematics, where their members display strongly pertur...

  15. The H-alpha echoes of Eta Carinae from 1985 to 1997

    Science.gov (United States)

    Boumis, P.; Meaburn, J.; Bryce, M.; Lopez, J. A.

    1998-02-01

    Spatially resolved, broad H-alpha line profiles from both the luminous blue variable star Eta Carinae (Eta Car) and the surrounding filamentary Car II ('Keyhole') nebula, where they have been scattered and reflected by dust, have been observed periodically from 1985 to 1997. The He-alpha line profiles from Eta Car in this 12-yr period show some, albeit not dramatic, changes. The sharp and deep P Cygni-type absorption feature that was observed first in 1985 in the broad, scattered/reflected profiles from the surrounding Keyhole nebula is not present in any of the direct Eta Car profiles. This distinctive feature is now shown to be spatially variable over the Keyhole nebula and most prominent along the direction of the axis of the bipolar Homunculus nebula at PA 132 deg. No evidence of any temporal variability of this sharp feature has been found in 12 yr of monitoring, even from the most well-defined scattering/reflecting cloud along PA 132 deg. It is concluded that a 46-deg-wide cone of light from Eta Car is relatively unobscured along the axis of the Homunculus nebula and that this must be the consequence of a dense torus close to the star.

  16. The giant H-alpha/X-ray filament in the cluster of galaxies A1795

    CERN Document Server

    Crawford, C S; Fabian, A C

    2005-01-01

    The cluster of galaxies A1795 hosts a 46 kpc-long filament at its core, which is clearly visible in the light of H-alpha and X-ray emission. We present optical slit spectroscopy and deeper Chandra X-ray data of the filament. The optical spectra reveal that the the bulk of the filament is quiescent (with sigma < 130 km/s), although considerable velocity structure is apparent around the powerful radio source in the central cluster galaxy, where a direct interaction is occurring between the radio plasma and the surrounding intracluster medium. The filament contains a clump of UV/blue continuum halfway along its length, which we resolve into a chain of at least 5 distinct knots using archival HST images; the optical spectrum of this clump confirm it to be mostly comprised of O stars. It is well-removed from the central galaxy and radio source, and is most likely an example of a group of young star clusters condensing directly from the cooling gas in the filament. The observed spatial offset between these knots...

  17. GH $\\alpha$ FaS : Galaxy H-alpha Fabry-Perot System for the WHT

    CERN Document Server

    Hernández, O; Carignan, C; Beckman, J; Gach, J L; Balard, P; Amram, P; Boulesteix, J; Corradi, R L M; de Denus-Baillargeon, M-M; Epinat, B; Relaño, M; Thibault, S; Vallée, P

    2008-01-01

    GH$\\alpha$FaS a new Fabry-Perot system, is now available at the William Herschel Telescope. It was mounted, for the first time, at the Nasmyth focus of the 4.2 meter WHT on La Palma in July 2007. Using modern technology, with a spectral resolution of the order R$\\sim$15000, and with a seeing limited spatial resolution, GH$\\alpha$FaS will provide a new look at the H$\\alpha$ -emitting gas over a 4.8 arcminutes circular field in the nearby universe. Many science programs can be done on a 4.2 metre class telescope in world class seeing conditions with a scanning Fabry-Perot. Not only galaxies but HII regions, planetary nebulae, supernova remnants and the diffuse interstellar medium are subjects for which unique data can be aquired rapidly. Astronomers from the Laboratoire d'Astrophysique Exp\\'erimentale (LAE) in Montr\\'eal, the Laboratoire d'Astrophysique de Marseille (LAM-OAMP), and the Instituto de Astrof\\'isica de Canarias (IAC), have inaugurated GH$\\alpha$FaS by studying in detail the dynamics of some nearby ...

  18. The KPNO International Spectroscopic Survey. V. H-alpha-selected Survey List 3

    CERN Document Server

    Jangren, A; Sarajedini, V L; Gronwall, C; Werk, J K; Chomiuk, L; Moody, J W; Boroson, T A; Jangren, Anna; Salzer, John J.; Sarajedini, Vicki L.; Gronwall, Caryl; Werk, Jessica K.; Chomiuk, Laura; Boroson, Todd A.

    2005-01-01

    The KPNO International Spectroscopic Survey (KISS) is an objective-prism survey designed to detect extragalactic emission-line objects. It combines many of the features of previous slitless spectroscopic surveys with the advantages of modern CCD detectors, and is the first purely digital objective-prism survey for emission-line galaxies (ELGs). Here we present the third list of ELG candidates selected from our red spectral data, which cover the wavelength range 6400 to 7200 A. In most cases, the detected emission line is H-alpha. The current survey list covers the region of the NOAO Deep Wide-Field Survey (NDWFS). This survey covers two fields; the first is 3 x 3 degrees square and located at RA = 14h 30m, DEC = 34.5 deg (B1950), the second is 2.3 x 4.0 degrees and centered at RA = 2h 7.5m, DEC = -4.75 deg. A total area of 19.65 deg^2 is covered by the KISS data. A total of 261 candidate emission-line objects have been selected for inclusion in the survey list (13.3 per deg^2). We tabulate accurate coordinate...

  19. The KPNO International Spectroscopic Survey. IV. H-alpha-selected Survey List 2

    CERN Document Server

    Gronwall, C; Sarajedini, V L; Jangren, A; Chomiuk, L; Moody, J; Frattare, L; Boroson, T A

    2004-01-01

    The KPNO International Spectroscopic Survey (KISS) is an objective-prism survey for extragalactic emission-line objects. It combines many of the features of previous slitless spectroscopic surveys with the advantages of modern CCD detectors, and is the first purely digital objective-prism survey for emission-line galaxies. Here we present the second list of emission-line galaxy candidates selected from our red spectral data, which cover the wavelength range 6400 to 7200 A. In most cases, the detected emission line is H-alpha. The current survey list covers a 1.6-degree-wide strip located at Dec(1950) = 43d 30' and spans the RA range 11h 55m to 16h 15m. The survey strip runs through the center of the Bootes Void, and has enough depth to adequately sample the far side of the void. An area of 65.8 sq. deg. is covered. A total of 1029 candidate emission-line objects have been selected for inclusion in the survey list (15.6 per sq. deg.). We tabulate accurate coordinates and photometry for each source, as well as ...

  20. Widths of surface knots

    CERN Document Server

    Takeda, Yasushi

    2009-01-01

    We study surface knots in 4-space by using generic planar projections. These projections have fold points and cusps as their singularities and the image of the singular point set divides the plane into several regions. The width (or the total width) of a surface knot is a numerical invariant related to the number of points in the inverse image of a point in each of the regions. We determine the widths of certain surface knots and characterize those surface knots with small total widths. Relation to the surface braid index is also studied.

  1. Nuclear-to-Disk Rotation Curves of Galaxies in the $H_{\\alpha}$ and [NII] Emission Lines

    CERN Document Server

    Sofue, Y; Tutui, Y; Honma, M; Takeda, Y; Sofue, Yoshiaki; Tomita, Akihiko; Tutui, Yoshinori; Honma, Mareki; Takeda, Yoichi

    1998-01-01

    We have obtained optical CCD spectroscopy along the major axes of 22 nearby spiral galaxies of Sb and Sc types in order to analyze their rotation curves. By subtracting the stellar continuum emission, we have obtained position velocity (PV) diagrams of the H alpha and [NII] lines. We point out that the H alphaline is often superposed by a broad stellar absorption feature (Balmer wind) in the nuclear regions, and, therefore, the [NII] line is a better tracer of kinematics in the central a few hundred pc regions. By applying the envelope-tracing technique to the H alpha and [NII] PV diagrams, we have derived nucleus-to-disk rotation curves of the observed galaxies. The rotation curves rise steeply within the central a few hundred parsecs, indicating rapidly rotating nuclear disk and mass concentration near the nucleus. [For more rotation curves : http://www.ioa.s.u-tokyo.ac.jp/

  2. Disparity between H\\alpha\\ and H\\beta\\ in SN 2008in: inhomogeneous external layers of type IIP supernovae?

    CERN Document Server

    Chugai, N N

    2013-01-01

    We study disparity between H\\alpha\\ and H\\beta\\ in early spectra of the type IIP supernova SN 2008in. The point is that these lines cannot be described simultaneously in a spherically-symmetric model with the smooth density distribution. It is shown that an assumption of a clumpy structure of external layers of the envelope resolves the problem. We obtain estimates of the velocity at the inner border of the inhomogeneous zone (\\approx6100 km s^{-1}), the filing factor of inhomogeneities (\\leq0.5), and the mass of the inhomogeneous layers (~ 0.03 M_{\\odot}). The amplitude of flux fluctuations in the early spectrum of H\\alpha\\ (\\Delta F/F ~ 10^{-2}) imposes a constraint on the size of inhomogeneities (\\leq 200 km s^{-1}). A detection of fluctuations in the early H\\alpha\\ of type IIP supernovae might become an observational test of the inhomogeneous structure of their envelopes. We propose also the indirect test of the clumpy structure of external layers: the study of properties of the initial radiation outburst...

  3. The Wyoming Survey for H-alpha. I. Initial Results at z ~ 0.16 and 0.24

    CERN Document Server

    Dale, Daniel A; Cohen, Seth A; Johnson, L Clifton; Kattner, ShiAnne M; Lamanna, Christine A; Moore, Carolynn A; Schuster, Micah D; Thatcher, Jacob W

    2008-01-01

    The Wyoming Survey for H-alpha, or WySH, is a large-area, ground-based, narrowband imaging survey for H-alpha-emitting galaxies over the latter half of the age of the Universe. The survey spans several square degrees in a set of fields of low Galactic cirrus emission. The observing program focuses on multiple dz~0.02 epochs from z~0.16 to z~0.81 down to a uniform (continuum+line) luminosity at each epoch of ~10^33 W uncorrected for extinction (3sigma for a 3" diameter aperture). First results are presented here for 98+208 galaxies observed over approximately 2 square degrees at redshifts z~0.16 and 0.24, including preliminary luminosity functions at these two epochs. These data clearly show an evolution with lookback time in the volume-averaged cosmic star formation rate. Integrals of Schechter fits to the extinction-corrected H-alpha luminosity functions indicate star formation rates per co-moving volume of 0.009 and 0.014 h_70 M_sun/yr/Mpc^3 at z~0.16 and 0.24, respectively. The formal uncertainties in the ...

  4. Dust attenuation in z $\\sim$ 1 galaxies from Herschel and 3D-HST H$\\alpha$ measurements

    CERN Document Server

    Puglisi, A; Franceschini, A; Talia, M; Cimatti, A; Baronchelli, I; Daddi, E; Renzini, A; Schawinski, K; Mancini, C; Silverman, J; Gruppioni, C; Lutz, D; Berta, S; Oliver, S J

    2015-01-01

    We combined the spectroscopic information from the 3D-HST survey with the PEP/Herschel data to characterize the H\\alpha dust attenuation properties of a sample of 79 normal star-forming galaxies at $0.7\\leq z\\leq1.5$ in the GOODS-S field. The sample was selected in the far-IR, at \\lambda=100 and/or 160 \\mu m, and only includes galaxies with a secure H\\alpha detection (S/N>3). From the low resolution 3D-HST spectra we measured z and F(H\\alpha) for the whole sample, rescaling the observed flux by a constant factor of 1.2 to remove the contamination by [NII]. The stellar masses, infrared and UV luminosities were derived from the SEDs by fitting multi-band data from GALEX near-UV to SPIRE500 \\mu m. We derived the continuum extinction Estar(B-V) from both the IRX ratio and the UV-slope, and found an excellent agreement among them. Galaxies in the sample have 2.6x10^9$\\leq$M*$\\leq$3.5x10^11 Msun, intense infrared luminosity (L_IR>1.2x10^10 Lsun), high level of dust obscuration (0.1$\\leq$Estar(B-V)$\\leq$1.1) and str...

  5. The Second Data Release of the INT Photometric H\\alpha\\ Survey of the Northern Galactic Plane (IPHAS DR2)

    CERN Document Server

    Barentsen, Geert; Drew, J E; González-Solares, E A; Greimel, R; Irwin, M J; Miszalski, B; Ruhland, C; Groot, P; Mampaso, A; Sale, S E; Henden, A A; Aungwerojwit, A; Barlow, M J; Carter, P J; Corradi, R L M; Drake, J J; Eislöffel, J; Fabregat, J; Gänsicke, B T; Fusillo, N P Gentile; Greiss, S; Hales, A S; Hodgkin, S; Huckvale, L; Irwin, J; King, R; Knigge, C; Kupfer, T; Lagadec, E; Lennon, D J; Lewis, J R; Mohr-Smith, M; Morris, R A H; Naylor, T; Parker, Q A; Phillipps, S; Pyrzas, S; Raddi, R; Roelofs, G H A; Rodríguez-Gil, P; Sabin, L; Scaringi, S; Steeghs, D; Suso, J; Tata, R; Unruh, Y C; van Roestel, J; Viironen, K; Vink, J S; Walton, N A; Wright, N J; Zijlstra, A A

    2014-01-01

    The INT/WFC Photometric H-Alpha Survey of the Northern Galactic Plane (IPHAS) is a 1800 square degrees imaging survey covering Galactic latitudes |b| < 5 deg and longitudes l = 30 to 215 deg in the r, i and H\\alpha\\ filters using the Wide Field Camera (WFC) on the 2.5-metre Isaac Newton Telescope (INT) in La Palma. We present the first quality-controlled and globally-calibrated source catalogue derived from the survey, providing single-epoch photometry for 219 million unique sources across 92% of the footprint. The observations were carried out between 2003 and 2012 at a median seeing of 1.1 arcsec (sampled at 0.33 arcsec/pixel) and to a mean 5\\sigma-depth of 21.2 (r), 20.0 (i) and 20.3 (H\\alpha) in the Vega magnitude system. We explain the data reduction and quality control procedures, describe and test the global re-calibration, and detail the construction of the new catalogue. We show that the new calibration is accurate to 0.03 mag (rms) and recommend a series of quality criteria to select the most rel...

  6. Evidence of Environmental Dependencies of Type Ia Supernovae from the Nearby Supernova Factory indicated by Local H{\\alpha}

    CERN Document Server

    Rigault, M; Aldering, G; Antilogus, P; Aragon, C; Bailey, S; Baltay, C; Bongard, S; Buton, C; Canto, A; Cellier-Holzem, F; Childress, M; Chotard, N; Fakhouri, H K; Feindt, U; Fleury, M; Gangler, E; Greskovic, P; Guy, J; Kim, A G; Kowalski, M; Lombardo, S; Nordin, J; Nugent, P; Pain, R; Pécontal, E; Pereira, R; Perlmutter, S; Rabinowitz, D; Runge, K; Saunders, C; Scalzo, R; Smadja, G; Tao, C; Thomas, R C; Weaver, B A

    2013-01-01

    (Abridged) We study the host galaxy regions in close proximity to Type Ia supernovae (SNe Ia) to analyze relations between the properties of SN Ia events and environments most similar to where their progenitors formed. We focus on local H\\alpha\\ emission as an indicator of young environments. The Nearby Supernova Factory has obtained flux-calibrated spectral timeseries for SNe Ia using integral field spectroscopy, allowing the simultaneous measurement of the SN and its immediate vicinity. For 89 SNe Ia we measure H\\alpha\\ emission tracing ongoing star formation within a 1 kpc radius around each SN. This constitutes the first direct study of the local environment for a large sample of SNe Ia also having accurate luminosity, color and stretch measurements. We find that SNe Ia with local H\\alpha\\ emission are redder by 0.036+/-0.017 mag, and that the previously-noted correlation between stretch and host mass is entirely driven by the SNe Ia coming from passive regions. Most importantly, the mean standardized bri...

  7. Nature of H-alpha selected galaxies at z>2. II. Clumpy galaxies and compact star-forming galaxies

    CERN Document Server

    Tadaki, Ken-ichi; Tanaka, Ichi; Hayashi, Masao; Koyama, Yusei; Shimakawa, Rhythm

    2013-01-01

    We present the morphological properties of 109 H\\alpha-selected galaxies at z>2 in SXDF-UDS-CANDELS field. With high-resolution optical/near-infrared images obtained by Hubble Space Telescope, we identify giant clumps within the H\\alpha emitters (HAEs). We find that at least 41% of our sample show clumpy structures in the underlying disks. The color gradient of clumps is commonly seen in the sense that the clumps near the galactic center tend to be redder than those in the outer regions. The mid-infrared detection in galaxies with red clumps and the spatial distribution of H\\alpha emission suggest that dusty star-formation activity is probably occurring in the nuclear red clumps. A gas supply to a bulge component through the clump migration is one of the most potent physical processes to produce such dusty star-forming clumps and form massive bulges in local early-type galaxies. They would become large quiescent galaxies at later times just by consumption or blowout of remaining gas. Also, while most of the H...

  8. Star-forming regions in gas-rich lenticulars. I. H-alpha imaging of an initial sample of galaxies

    International Nuclear Information System (INIS)

    The first results of an H-alpha imaging survey of H I rich S0 and S0/a galaxies are presented. Analysis of CCD H-alpha interference-filter images of 16 galaxies is reported. Eight of these galaxies show evidence for ongoing star formation, one has nuclear emission but no H II regions, and the remaining seven have no emission detected with well-defined upper limits. A few of the galaxies with H II regions exhibit global peculiarities, while the others have essentially normal appearances. In the peculiar galaxies, the emission from H II regions appears pervasive, while in the apparently normal galaxies the H II regions are either organized into inner-disk rings or randomly distributed throughout the disk. A few of the galaxies are found to be clearly not S0s, or peculiar objects atypical of the S0 class. Using simple models, star-formation rates are derived from the observed H-alpha fluxes, and an estimate of gas-depletion time scales is made. 80 references

  9. Evidence that [3H]-alpha,beta-methylene ATP may label an endothelial-derived cell line 5'-nucleotidase with high affinity.

    OpenAIRE

    Michel, A. D.; Chau, N. M.; Fan, T. P.; E.E. Frost; Humphrey, P. P.

    1995-01-01

    1. In membranes prepared from a permanent cell line of endothelial origin (WEC cells), [3H]-alpha, beta-methylene ATP ([3H]-alpha, beta-meATP) labelled high (pKd = 9.5; Bmax = 3.75 pmol mg-1 protein) and low (pKd = 7.2; Bmax = 23.3 pmol mg-1 protein) affinity binding sites. The high affinity [3H]-alpha, beta-meATP binding sites in the WEC cell membranes could be selectively labelled with a low concentration of the radioligand (1 nM). In competition studies performed at a radioligand concentra...

  10. High- and low-affinity binding sites for [3H]-alpha, beta-methylene ATP in rat urinary bladder membranes.

    OpenAIRE

    Bo, X. N.; Burnstock, G.

    1990-01-01

    1. The characteristics of [3H]-alpha, beta-methylene adenosine 5'triphosphate ([3H]-alpha, beta-MeATP) binding to membrane preparations of rat urinary bladder detrusor were studied. 2. The rat bladder membrane preparation was obtained by multiple centrifugation. [3H]-quinuclidinyl benzilate [( 3H]-QNB) binding to this preparation demonstrated that the muscarinic receptor density was 4.32 times higher than that in the homogenate. [3H]-alpha, beta-MeATP binding was increased 3.88 times. 3. Satu...

  11. Spitzer IRAC observations of newly-discovered planetary nebulae from the Macquarie-AAO-Strasbourg H-alpha Planetary Nebula Project

    OpenAIRE

    Cohen, Martin; Parker, Quentin A; Green, Anne J.; Murphy, Tara; Miszalski, Brent; Frew, David J.; Marilyn R. Meade; Babler, Brian; Indebetouw, Remy; Whitney, Barbara A.; Watson, Christer; Churchwell, Edward B.; Watson, Douglas F.

    2007-01-01

    We compare H-alpha, radio continuum, and Spitzer Space Telescope (SST) images of 58 planetary nebulae (PNe) recently discovered by the Macquarie-AAO-Strasbo- urg H-alpha PN Project (MASH) of the SuperCOSMOS H-alpha Survey. Using InfraRed Array Camera (IRAC) data we define the IR colors of PNe and demonstrate good isolation between these colors and those of many other types of astronomical object. The only substantive contamination of PNe in the color-color plane we illustrat...

  12. Equivalent Fractions

    Science.gov (United States)

    2012-07-31

    In this NCTM Android app a user identifies equivalent fractions for a given random fraction or one of the player's own. The user creates their representations by dividing and shading either a square or circular region. The fractions are shown as locations on the number line and their equivalency is demonstrated when they are at the same point. The user has the ability to construct a table of equivalent fractions. This app is related to an Illuminations activity and an iOS app that are cataloged separately.

  13. SUB-THz AND H{alpha} ACTIVITY DURING THE PREFLARE AND MAIN PHASES OF A GOES CLASS M2 EVENT

    Energy Technology Data Exchange (ETDEWEB)

    Kaufmann, Pierre; Gimenez de Castro, C. Guillermo; Raulin, Jean-Pierre; Correia, Emilia; Fernandes, Luis Olavo; De Souza, Rodney V. [CRAAM, Escola de Engenharia, Universidade Presbiteriana Mackenzie, Sao Paulo (Brazil); Marcon, Rogerio [IFGW, Universidade Estadual de Campinas (Brazil); White, Stephen M. [AFRL, Space Vehicles Directorate, Albuquerque, NM (United States); Godoy, Rodolfo; Marun, Adolfo; Pereyra, Pablo [Complejo Astronomico El Leoncito, CONICET, San Juan (Argentina)

    2011-12-01

    Radio and optical observations of the evolution of flare-associated phenomena have shown an initial and rapid burst at 0.4 THz only followed subsequently by a localized chromospheric heating producing an H{alpha} brightening with later heating of the whole active region. A major instability occurred several minutes later producing one impulsive burst at microwaves only, associated with an M2.0 GOES X-ray flare that exhibited the main H{alpha} brightening at the same site as the first flash.The possible association between long-enduring time profiles at soft X-rays, microwaves, H{alpha}, and sub-THz wavelengths is discussed. In the decay phase, the H{alpha} movie shows a disrupting magnetic arch structure ejecting dark, presumably chromospheric, material upward. The time sequence of events suggests genuine interdependent and possibly non-thermal instabilities triggering phenomena, with concurrent active region plasma heating and material ejection.

  14. Sub-THz and H{\\alpha} activity during the preflare and main phases of a GOES class M2 event

    CERN Document Server

    Kaufmann, Pierre; de Castro, C Guillermo Giménez; White, Stephen M; Raulin, Jean-Pierre; Correia, Emilia; Fernandes, Luis Olavo; de Souza, Rodney V; Godoy, Rodolfo; Marun, Adolfo; Pereyra, Pablo

    2011-01-01

    Radio and optical observations of the evolution of flare-associated phenomena have shown an initial and rapid burst at 0.4 THz only followed subsequently by a localized chromospheric heating producing an H{\\alpha} brightening with later heating of the whole active region. A major instability occurred several minutes later producing one impulsive burst at microwaves only, associated with an M2.0 GOES X-ray flare that exhibited the main H{\\alpha} brightening at the same site as the first flash. The possible association between long-enduring time profiles at soft X-rays, microwaves, H{\\alpha} and sub-THz wavelengths is discussed. In the decay phase the H{\\alpha} movie shows a disrupting magnetic arch structure ejecting dark, presumably chromospheric, material upwards. The time sequence of events suggests genuine interdependent and possibly non-thermal instabilities triggering phenomena, with concurrent active region plasma heating and material ejection.

  15. FUNDPAR: A program for Deriving Fundamental Parameters from Equivalent Widths

    Directory of Open Access Journals (Sweden)

    C. Saffe

    2011-01-01

    Full Text Available Implementamos un programa en Fortran que determina parámetros fundamentales de estrellas de tipo solar, a partir de anchos equivalentes del Fe. La solución debe verificar tres condiciones en el método estándar: equilibrio de ionización, equilibrio de excitación e independencia entre abundancias y anchos equivalentes. Calculamos modelos de atmósfera de Kurucz con opacidades NEWODF. Detalles como el parámetro de longitud de mezcla, el sobre impulso convectivo, etc. se calculan con un programa independiente. FUNDPAR calcula las incertezas por dos métodos: el criterio de Gonzalez & Vanture (1998 y utilizando la función X² . Los resultados derivados con FUNDPAR están de acuerdo con determinaciones previas en la literatura. En particular obtuvimos parámetros fundamentales de 58 estrellas con exoplanetas. El programa está disponible en la red1.

  16. Games for width parameters and monotonicity

    CERN Document Server

    Adler, Isolde

    2009-01-01

    We introduce a search game for two players played on a "scenario" consisting of a ground set together with a collection of feasible partitions. This general setting allows us to obtain new characterisations of many width parameters such as rank-width and carving-width of graphs, matroid tree-width and GF(4)-rank-width. We show that the monotone game variant corresponds to a tree decomposition of the ground set along feasible partitions. Our framework also captures many other decompositions into "simple" subsets of the ground set, such as decompositions into planar subgraphs. Within our general framework, we take a step towards characterising monotone search games. We exhibit a large class of "monotone" scenarios, i.e. of scenarios where the game and its monotone variant coincide. As a consequence, determining the winner is in NP for these games. This result implies monotonicity for all our search games, that are equivalent to branch-width of a submodular function. Finally, we include a proof showing that the ...

  17. Disparity between H\\alpha\\ and H\\beta\\ in SN 2008in: inhomogeneous external layers of type IIP supernovae?

    OpenAIRE

    Chugai, N. N.; Utrobin, V. P.

    2013-01-01

    We study disparity between H\\alpha\\ and H\\beta\\ in early spectra of the type IIP supernova SN 2008in. The point is that these lines cannot be described simultaneously in a spherically-symmetric model with the smooth density distribution. It is shown that an assumption of a clumpy structure of external layers of the envelope resolves the problem. We obtain estimates of the velocity at the inner border of the inhomogeneous zone (\\approx6100 km s^{-1}), the filing factor of inh...

  18. Scattering polarization and the Hanle effect in H-alpha as a probe of chromospheric magnetism: Modeling vs. Observations

    CERN Document Server

    Stepan, Jiri; Ramelli, Renzo; Bianda, Michele

    2011-01-01

    The Hanle effect in strong spectral lines is the physical mechanism that should be increasingly exploited for quantitative explorations of the magnetism of the quiet solar chromospheric plasma. Here we show, by means of multilevel radiative transfer calculations and new spectropolarimetric observations, that the amplitude and shape of the scattering polarization profiles of the H-alpha line is very sensitive to the strength and structure of the chromospheric magnetic field. The interpretation of the observations in terms of one-dimensional radiative transfer modeling suggests that there is an abrupt magnetization in the upper chromosphere of the quiet Sun.

  19. Using MHD simulations to model H-alpha and UV spectral lines for interpretation of IRIS and NST data

    OpenAIRE

    Sadykov, Viacheslav M.; Kosovichev, Alexander G.

    2014-01-01

    We present results of non-LTE modeling of H-alpha 6563 A and Mg II k&h 2796 A and 2803 A lines. This modeling is important for interpretation of coordinated observations from the recently launched NASA's IRIS mission and from the New Solar Telescope at Big Bear Solar Observatory. Among available codes for the non-LTE modeling, the RH code is chosen as the most appropriate for modeling of the line profiles. The most suitable Hydrogen and Magnesium atomic models are selected b...

  20. Protoplanetary Disks in the Orion Nebula: An H$\\alpha$ Fabry-Perot study and Astrobiological Aspects

    OpenAIRE

    La Fuente, Eduardo; Rosado, Margarita; Arias, Lorena; Ambrocio-cruz, Patricia; Throop, Henry B.

    2002-01-01

    In this paper, we present a briefly overview of the protoplanetary disks in the Orion Nebula, incluiding some astrobiological aspects and an H$\\alpha$ Fabry-Perot study of 16 of them. We found that Fabry-Perot interferometry constitutes an effective technique for the detection of proplyds. We also report heliocentric systemic velocities for the proplyds 82-336, 158-323, 158-326, 159-350, 161-314, 161-324, 163-317, 166-316, 167-317, 168-326, 170-337, 176-325, 177-341, 180-331...

  1. Tree-width for first order formulae

    CERN Document Server

    Adler, Isolde

    2012-01-01

    We introduce tree-width for first order formulae phi, fotw(phi). We show that computing fotw is fixed-parameter tractable with parameter fotw. Moreover, we show that on classes of formulae of bounded fotw, model checking is fixed parameter tractable, with parameter the length of the formula. This is done by translating a formula phi with fotw(phi)equivalent to an L^k formula is undecidable. In contrast, the classes of first order formulae with bounded fotw are fragments of first order logic for which the equivalence is decidable. Our notion of tree-width generalises tree-width of conjunctive queries to arbitrary formulae of first order logic by taking into account the quantifier interaction in a formula. Moreover, it is more powerful than the notion of elimination-width of quantified constraint formulae, defined by Chen and Dalmau (CSL 2005): for quantified constraint form...

  2. Initial Data Release from the INT Photometric H-alpha Survey of the Northern Galactic Plane (IPHAS)

    CERN Document Server

    González-Solares, E A; Greimel, R; Drew, J E; Irwin, M J; Sale, S E; Andrews, K; Aungwerojwit, A; Barlow, M J; Besselaar, E van den; Corradi, R L M; Gänsicke, B T; Groot, P J; Hales, A S; Hopewell, E C; Hu, H; Irwin, J; Knigge, C; Lagadec, E; Leisy, P; Lewis, J R; Mampaso, A; Matsuura, M; Moont, B; Morales-Rueda, L; Morris, R A H; Naylor, T; Parker, Q A; Prema, P; Pyrzas, S; Rixon, G T; Rodríguez-Gil, P; Roelofs, G; Sabin, L; Skillen, I; Suso, J; Tata, R; Viironen, K; Vink, J S; Witham, A; Wright, N J; Zijlstra, A A; Zurita, A; Drake, J; Fabregat, J; Lennon, D J; Lucas, P W; Martín, E L; Steeghs, D; Unruh, Y C

    2007-01-01

    The INT/WFC Photometric H-alpha Survey of the Northern Galactic Plane (IPHAS) is an imaging survey being carried out in H-alpha, r' and i' filters, with the Wide Field Camera (WFC) on the 2.5-metre Isaac Newton Telescope (INT) to a depth of r'=20 (10 sigma). The survey is aimed at revealing large scale structure in our local galaxy, and also the properties of key early and late populations making up the Milky Way. Mapping emission line objects enables a particular focus on objects in the young and old stages of stellar evolution ranging from early T-Tauri stars to late planetary nebulae. In this paper we present the IPHAS Initial Data Release, primarily a photometric catalogue of about 200 million unique objects, coupled with associated image data covering about 1600 square degrees in three passbands. We note how access to the primary data products has been implemented through use of standard virtual observatory publishing interfaces. Simple traditional web access is provided to the main IPHAS photometric cat...

  3. Photometric H alpha and [O II] Luminosity Function of SDF and SXDF Galaxies: Implications for Future Baryon Oscillation Surveys

    CERN Document Server

    Sumiyoshi, Masanao; Oshige, Shunsuke; Glazebrook, Karl; Akiyama, Masayuki; Morokuma, Tomoki; Motohara, Kentaro; Shimasaku, Kazuhiro; Hayashi, Masao; Yoshida, Makiko; Kashikawa, Nobunari; Kodama, Tadayuki

    2009-01-01

    Efficient selection of emission line galaxies at z > 1 by photometric information in wide field surveys is one of the keys for future spectroscopic surveys to constrain dark energy using the baryon acoustic oscillation (BAO) signature. Here we estimate the H alpha and [O II] line luminosity functions of galaxies at z = 0.5-1.7 using a novel approach where multi-wavelength imaging data is used to jointly estimate both photometric redshifts and star-formation rates. These photometric estimates of line luminosities at high-redshift use the large data sets of the Subaru Deep Field and Subaru XMM-Newton Deep Field (covering \\sim 1 deg^2) and are calibrated with the spectroscopic data of the local Sloan Digital Sky Survey galaxies. The derived luminosity functions (especially H alpha) are in reasonable agreement with the past estimates based on spectroscopic or narrow-band-filter surveys. This dataset is useful for examining the photometric selection of target galaxies for BAO surveys because of the large cosmologi...

  4. Using MHD simulations to model H-alpha and UV spectral lines for interpretation of IRIS and NST data

    CERN Document Server

    Sadykov, Viacheslav M

    2014-01-01

    We present results of non-LTE modeling of H-alpha 6563 A and Mg II k&h 2796 A and 2803 A lines. This modeling is important for interpretation of coordinated observations from the recently launched NASA's IRIS mission and from the New Solar Telescope at Big Bear Solar Observatory. Among available codes for the non-LTE modeling, the RH code is chosen as the most appropriate for modeling of the line profiles. The most suitable Hydrogen and Magnesium atomic models are selected by performing several tests of the code. The influence of the ionization degree on the line profiles is also studied. Radiative-MHD simulations of the solar atmosphere, obtained with the Bifrost code, are used as input data for calculation of synthetic spectra of the H-alpha and Mg II h&k lines for particular locations evolving with time. The spectral line variations reveal the presence of MHD waves in the simulation results. We construct oscillation power spectra of the line intensity for different wavelength, and compare these wit...

  5. The Kinematics of Arp 295 in H-alpha Emission: an Interacting Galaxy with Highly Asymmetric Rotation

    CERN Document Server

    Roche, N

    2006-01-01

    We investigate Arp 295, a pair of interacting spirals at z=0.023. We measure scalelengths 5.24 kpc for Arp 295a and 2.52 kpc for 295b. There is a much smaller Im galaxy associated with the larger spiral. Arp 295b is asymmetric with the disk more extended eastwards but with the brightest star-formation regions on the west side of the nucleus. The spectrum of Arp 295b shows strong emission lines with [OII]3727 prominent We measure the total H-alpha line luminosities of Arp 295b and Arp 295c as 4.58x 10^{41} and 6.76x 10^{40} ergs/s, corresponding to star-formation rates 3.6 and 0.53. To study the kinematics of Arp 295b we observe in H-alpha with the Manchester Echelle Spectrograph, using an E-W spectroscopic slit at a series of 9 positions. We measure the maximum disk rotation velocity as 252.6 km/s. The rotation curve of Arp 295b is very asymmetric. The east (approaching) side has a higher radial velocity than the west with the maximum difference at radius 5 arcsec from the nucleus, where it is 88 km/s. The sl...

  6. A Note on Graphs of Linear Rank-Width 1

    OpenAIRE

    Bui-Xuan, Binh-Minh; Kanté, Mamadou Moustapha; Limouzy, Vincent

    2013-01-01

    We prove that a connected graph has linear rank-width 1 if and only if it is a distance-hereditary graph and its split decomposition tree is a path. An immediate consequence is that one can decide in linear time whether a graph has linear rank-width at most 1, and give an obstruction if not. Other immediate consequences are several characterisations of graphs of linear rank-width 1. In particular a connected graph has linear rank-width 1 if and only if it is locally equivale...

  7. COMPARING H{alpha} AND H I SURVEYS AS MEANS TO A COMPLETE LOCAL GALAXY CATALOG IN THE ADVANCED LIGO/VIRGO ERA

    Energy Technology Data Exchange (ETDEWEB)

    Metzger, Brian D. [Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08542 (United States); Kaplan, David L. [Physics Department, University of Wisconsin-Milwaukee, Milwaukee, WI 53211 (United States); Berger, Edo, E-mail: bmetzger@astro.princeton.edu, E-mail: kaplan@uwm.edu, E-mail: eberger@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)

    2013-02-20

    Identifying the electromagnetic counterparts of gravitational wave (GW) sources detected by upcoming networks of advanced ground-based interferometers will be challenging, due in part to the large number of unrelated astrophysical transients within the {approx}10-100 deg{sup 2} sky localizations. A potential way to greatly reduce the number of such false positives is to limit detailed follow-up to only those candidates near galaxies within the GW sensitivity range of {approx}200 Mpc for binary neutron star mergers. Such a strategy is currently hindered by the fact that galaxy catalogs are grossly incomplete within this volume. Here, we compare two methods for completing the local galaxy catalog: (1) a narrowband H{alpha} imaging survey and (2) an H I emission line radio survey. Using H{alpha} fluxes, stellar masses (M {sub *}), and star formation rates (SFRs) from galaxies in the Sloan Digital Sky Survey (SDSS), combined with H I data from the GALEX Arecibo SDSS Survey and the Herschel Reference Survey, we estimate that an H{alpha} survey with a luminosity sensitivity of L {sub H{alpha}} = 10{sup 40} erg s{sup -1} at 200 Mpc could achieve a completeness of f {sup H{alpha}} {sub SFR} Almost-Equal-To 75% with respect to total SFR, but only f{sub M* Star-Operator }{sup H{alpha}} approx. 33% with respect to M {sub *} (due to lack of sensitivity to early-type galaxies). These numbers are significantly lower than those achieved by an idealized spectroscopic survey due to the loss of H{alpha} flux resulting from resolving out nearby galaxies and the inability to correct for the underlying stellar continuum. An H I survey with sensitivity similar to the proposed WALLABY survey on ASKAP could achieve f{sub SFR}{sup H{sub I}} Almost-Equal-To 80% and f{sub M Star-Operator }{sup H{sub I}} Almost-Equal-To 50%, somewhat higher than that of the H{alpha} survey. Finally, both H{alpha} and H I surveys should achieve {approx}> 50% completeness with respect to the host galaxies of short-duration gamma-ray bursts, which may trace the population of binary neutron star mergers.

  8. A test of arm-induced star formation in spiral galaxies from near-IR and H$\\alpha$ imaging

    CERN Document Server

    Seigar, M S; Seigar, Marc S.; James, Phil A.

    2002-01-01

    We have imaged a sample of 20 spiral galaxies in H$\\alpha$ and in the near-infrared K band (2.2 um), in order to determine the location and strength of star formation in these objects with respect to perturbations in the old stellar population. We have found that star formation rates are significantly enhanced in the vicinity of K band arms. We have also found that this enhancement in star formation rate in arm regions correlates well with a quantity that measures the relative strengths of shocks in arms. Assuming that the K band light is dominated by emission from the old stellar population, this shows that density waves trigger star formation in the vicinity of spiral arms.

  9. Protoplanetary Disks in the Orion Nebula An H$\\alpha$ Fabry-Perot study and Astrobiological Aspects

    CERN Document Server

    De la Fuente-Acosta, E; Arias, L; Throop, H B; Ambrocio-Cruz, P; Fuente, Eduardo de la; Rosado, Margarita; Arias, Lorena; Throop, Patricia Ambrocio-Cruz & Henry B.

    2002-01-01

    In this paper, we present a briefly overview of the protoplanetary disks in the Orion Nebula, incluiding some astrobiological aspects and an H$\\alpha$ Fabry-Perot study of 16 of them. We found that Fabry-Perot interferometry constitutes an effective technique for the detection of proplyds. We also report heliocentric systemic velocities for the proplyds 82-336, 158-323, 158-326, 159-350, 161-314, 161-324, 163-317, 166-316, 167-317, 168-326, 170-337, 176-325, 177-341, 180-331, 197-427 and 244-440. The velocities were measured between 22-38 km s$^{-1}$.

  10. The Wyoming Survey for H-alpha. III. A Multi-wavelength Look at Attenuation by Dust in Galaxies out to z~0.4

    OpenAIRE

    Moore, Carolynn A.; Dale, Daniel A.; Barlow, Rebecca J.; Cohen, Seth A.; Cook, David O.; Johnson, L. C.; Kattner, Shianne M.; Lee, Janice C.; Staudaher, Shawn M.

    2010-01-01

    We report results from the Wyoming Survey for H-alpha (WySH), a comprehensive four-square degree survey to probe the evolution of star-forming galaxies over the latter half of the age of the Universe. We have supplemented the H-alpha data from WySH with infrared data from the Spitzer Wide-area Infrared Extragalactic (SWIRE) Survey and ultraviolet data from the Galaxy Evolution Explorer (GALEX) Deep Imaging Survey. This dataset provides a multi-wavelength look at the evolutio...

  11. Sub-THz and H{\\alpha} activity during the preflare and main phases of a GOES class M2 event

    OpenAIRE

    Kaufmann, Pierre; Marcon, Roge?rio; Castro, C. Guillermo Gime?nez; White, Stephen M.; Raulin, Jean-pierre; Correia, Emilia; Fernandes, Luis Olavo; Souza, Rodney V.; Godoy, Rodolfo; Marun, Adolfo; Pereyra, Pablo

    2011-01-01

    Radio and optical observations of the evolution of flare-associated phenomena have shown an initial and rapid burst at 0.4 THz only followed subsequently by a localized chromospheric heating producing an H{\\alpha} brightening with later heating of the whole active region. A major instability occurred several minutes later producing one impulsive burst at microwaves only, associated with an M2.0 GOES X-ray flare that exhibited the main H{\\alpha} brightening at the same site a...

  12. The MOSDEF Survey: Dissecting the star-formation rate vs. stellar mass relation using H$\\alpha$ and H$\\beta$ emission lines at z ~ 2

    CERN Document Server

    Shivaei, Irene; Shapley, Alice E; Kriek, Mariska; Siana, Brian; Mobasher, Bahram; Coil, Alison L; Freeman, William R; Sanders, Ryan; Price, Sedona H; de Groot, Laura; Azadi, Mojegan

    2015-01-01

    We present results on the SFR-$M_*$ relation (i.e., the "main sequence") among star-forming galaxies at $1.37\\leq z \\leq2.61$ using the MOSFIRE Deep Evolution Field (MOSDEF) survey. Based on a sample of 261 star-forming galaxies with observations of H$\\alpha$ and H$\\beta$ emission lines, we have estimated robust dust-corrected instantaneous star-formation rates (SFRs) over a large dynamic range in stellar mass ($\\sim 10^{9.0}-10^{11.5}M_\\odot$). We find a tight correlation between SFR(H$\\alpha$) and $M_*$ with an intrinsic scatter of 0.36 dex, 0.05 dex larger than that of UV-based SFRs. This increased scatter is consistent with predictions from numerical simulations of 0.03 - 0.1 dex, and is attributed to H$\\alpha$ more accurately tracing SFR variations. The slope of the $\\log(\\text{SFR})-\\log(M_*)$ relation, using SFR(H$\\alpha$), at $1.4< z<2.6$ and over the stellar mass range of $10^{9.5}$ to $10^{11.5}M_\\odot$ is $0.65\\pm 0.09$. We find that different assumptions for the dust correction, such as usin...

  13. The Wyoming Survey for H-alpha. III. A Multi-wavelength Look at Attenuation by Dust in Galaxies out to z~0.4

    CERN Document Server

    Moore, Carolynn A; Barlow, Rebecca J; Cohen, Seth A; Cook, David O; Johnson, L C; Kattner, ShiAnne M; Lee, Janice C; Staudaher, Shawn M

    2010-01-01

    We report results from the Wyoming Survey for H-alpha (WySH), a comprehensive four-square degree survey to probe the evolution of star-forming galaxies over the latter half of the age of the Universe. We have supplemented the H-alpha data from WySH with infrared data from the Spitzer Wide-area Infrared Extragalactic (SWIRE) Survey and ultraviolet data from the Galaxy Evolution Explorer (GALEX) Deep Imaging Survey. This dataset provides a multi-wavelength look at the evolution of the attenuation by dust, and here we compare a traditional measure of dust attenuation (L(TIR)/L(FUV)) to a diagnostic based on a recently-developed robust star formation rate (SFR) indicator, [H-alpha_obs+24-micron]/H-alpha_obs. With such data over multiple epochs, the evolution in the attenuation by dust with redshift can be assessed. We present results from the ELAIS-N1 and Lockman Hole regions at z~0.16, 0.24, 0.32 and 0.40. While the ensemble averages of both diagnostics are relatively constant from epoch to epoch, each epoch ind...

  14. The FMOS-COSMOS survey of star-forming galaxies at z ~ 1.6 I. H\\alpha -based star formation rates and dust extinction

    CERN Document Server

    Kashino, D; Rodighiero, G; Renzini, A; Arimoto, N; Daddi, E; Lilly, S J; Sanders, D B; Kartaltepe, J; Zahid, H J; Nagao, T; Sugiyama, N; Capak, P; Carollo, C M; Chu, J; Hasinger, G; Ilbert, O; Kajisawa, M; Kewley, L J; Koekemoer, A M; Kova?, K; Fèvre, O Le; Masters, D; McCracken, H J; Onodera, M; Scoville, N; Strazzullo, V; Symeonidis, M; Taniguchi, Y

    2013-01-01

    We present first results from a near-infrared spectroscopic survey of the COSMOS field, using the Fiber Multi-Object Spectrograph (FMOS) on the Subaru telescope, designed to characterize the star-forming galaxy population at 1.4H\\alpha\\ in emission between 1.6-1.8\\mu m with $f_H\\alpha\\ \\gtrsim 4 \\times 10^{-17} ergs cm^{-2} s^{-1}$. Here, we specifically focus on 271 sBzK-selected galaxies that yield a H\\alpha\\ detection thus providing a redshift and emission-line luminosity to establish the relation between star formation rate (SFR) and stellar mass. With further J-band spectroscopy for 89 of these, the level of dust extinction is assessed by measuring the Balmer decrement using co-added spectra. We find that the extinction (0.6\\lesssim A_H\\alpha\\ \\lesssim 2.5) rises with stellar mass and is elevated at high masses compared to low-redshift galaxies. Using this subset of the spectroscopic sample, we further find that the differential extinction b...

  15. Star formation at z=1.47 from HiZELS: An H{\\alpha}+[OII] double-blind study

    CERN Document Server

    Sobral, David; Matsuda, Yuichi; Smail, Ian; Geach, James; Cirasuolo, Michele

    2011-01-01

    This paper presents the results from the first wide and deep dual narrow-band survey to select H-alpha (Ha) and [OII] line emitters at z=1.47\\pm0.02 (using matched narrow-band filters in the H and z' bands), exploiting synergies between the UKIRT and Subaru telescopes. The Ha survey at z=1.47 reaches a flux limit of ~7x10^-17 erg/s/cm^2 and detects ~200 Ha emitters over 0.7deg^2, while the much deeper [OII] survey reaches an effective flux of ~7x10^-18 erg/s/cm^2, detecting ~1400 z=1.47 [OII] emitters in a matched co-moving volume of ~2.5x10^5 Mpc^3. The combined survey results in the identification of 190 simultaneous Ha and [OII] emitters at z=1.47. Ha and [OII] luminosity functions are derived and both are shown to evolve significantly from z~0 in a consistent way. The star formation rate density of the Universe at z=1.47 is evaluated, with the Ha analysis yielding 0.16\\pm0.05 M_sun/yr/Mpc^3 and the [OII] analysis 0.17\\pm0.04 M_sun/yr/Mpc^3. The measurements are combined with other studies, providing a sel...

  16. ESO-H$\\alpha$~574 and Par-Lup3-4 Jets: Exploring the spectral, kinematical and physical properties

    CERN Document Server

    Whelan, E T; Antoniucci, S; Alcalá, J M; Giannini, T; Nisini, B; Bacciotti, F; Podio, L; Stelzer, B; Comerón, F

    2014-01-01

    In this paper a comprehensive analysis of VLT / X-Shooter observations of two jet systems, namely ESO-H$\\alpha$ 574 a K8 classical T Tauri star and Par-Lup 3-4 a very low mass (0.13~\\Msun) M5 star, is presented. Both stars are known to have near-edge on accretion disks. A summary of these first X-shooter observations of jets was given in a 2011 letter. The new results outlined here include flux tables of identified emission lines, information on the morphology, kinematics and physical conditions of both jets and, updated estimates of $\\dot{M}_{out}$ / $\\dot{M}_{acc}$. Asymmetries in the \\eso flow are investigated while the \\para jet is much more symmetric. The density, temperature, and therefore origin of the gas traced by the Balmer lines are investigated from the Balmer decrements and results suggest an origin in a jet for \\eso while for \\para the temperature and density are consistent with an accretion flow. $\\dot{M}_{acc}$ is estimated from the luminosity of various accretion tracers. For both targets, ne...

  17. Phase width reduction project summary

    International Nuclear Information System (INIS)

    The purpose of the phase width reduction project, 1993--96, was to reduce the phase width of the 88-Inch Cyclotron beam on target from 5--10 ns to 1--2 ns for certain experiments, such as Gammasphere, which use time-of-flight identification. Since reducing the phase width also reduces beam intensity, tuning should be done to also optimize the transmission. The Multi-turn Collimator slits in the cyclotron center region were used to collimate the early turns radially, thus reducing the phase width from about 5 ns to 1--2 ns FWHM for a Gammasphere beam. The effect of the slits on phase width was verified with a Fast Faraday Cup and with particle and gamma-ray detectors in the external beamline

  18. CAWSES Related Projects in Japan : Grant-in-Aid for Creative Scientific Research ügBasic Study of Space Weather Predictionüh and CHAIN (Continuous H Alpha Imaging Network)

    Science.gov (United States)

    Shibata, K.; Kurokawa, H.

    The Grant-in-Aid for Creative Scientific Research of the Ministry of Education Science Sports Technology and Culture of Japan The Basic Study of Space Weather Prediction PI K Shibata Kyoto Univ has started in 2005 as 5 years projects with total budget 446Myen The purpose of this project is to develop a physical model of solar-terrestrial phenomena and space storms as a basis of space weather prediction by resolving fundamental physics of key phenomena from solar flares and coronal mass ejections to magnetospheric storms under international cooperation program CAWSES Climate and Weather of the Sun-Earth System Continuous H Alpha Imaging Network CHAIN Project led by H Kurokawa is a key project in this space weather study enabling continuous H alpha full Sun observations by connecting many solar telescopes in many countries through internet which provides the basis of the study of space weather prediction

  19. Hydrodynamical and radiative modeling of temporal H{\\alpha} emission V/R variations caused by a discontinuous mass transfer in binaries

    CERN Document Server

    Chadima, Pavel; Harmanec, Petr; Wolf, Marek; Ruzdjak, Domagoj; Bozic, Hrvoje; Koubsky, Pavel

    2011-01-01

    H{\\alpha} emission V/R variations caused by a discontinous mass transfer in interacting binaries with a rapidly rotating accreting star are modelled qualititatively for the first time. The program ZEUS-MP was used for a non-linear 3-D hydrodynamical modeling of a development of a blob of gaseous material injected into an orbit around a star. It resulted in the formation of an elongated disk with a slow prograde revolution. The LTE radiative transfer program SHELLSPEC was used to calculate the H{\\alpha} profiles originating in the disk for several phases of its revolution. The profiles have the form of a double emission and exhibit V/R and radial velocity variations. However, these variations should be a temporal phenomenon since imposing a viscosity in given model would lead to a circularization of the disk and fading-out of given variations.

  20. Dynamics of blue compact galaxies, as revealed by their H$\\alpha$ velocity fields II. Mass models and the starburst triggering mechanism

    OpenAIRE

    Ostlin, G.; Amram, P.; Bergvall, N.; Masegosa, J.; Boulesteix, J.; Marquez, I.

    2001-01-01

    The H$\\alpha$ velocity fields of a sample of six luminous blue compact galaxies (BCGs) and two companions have been obtained by observations with a scanning Fabry-Perot interferometer. The Fabry-Perot images, velocity fields and rotations curves have been presented in a previous paper (Paper I). In general, the velocity fields are irregular and often contain secondary dynamical components, but display overall rotation. The two companions have more regular velocity fields and...

  1. The Subaru FMOS Galaxy Redshift Survey (FastSound). I. Overview of the Survey Targeting on H$\\alpha$ Emitters at $z \\sim 1.4$

    CERN Document Server

    Tonegawa, Motonari; Okada, Hiroyuki; Akiyama, Masayuki; Dalton, Gavin; Glazebrook, Karl; Iwamuro, Fumihide; Maihara, Toshinori; Ohta, Kouji; Shimizu, Ikkoh; Takato, Naruhisa; Tamura, Naoyuki; Yabe, Kiyoto; Bunker, Andrew J; Coupon, Jean; Ferreira, Pedro G; Frenk, Carlos S; Goto, Tomotsugu; Hikage, Chiaki; Ishikawa, Takashi; Matsubara, Takahiko; More, Surhud; Okumura, Teppei; Percival, Will J; Spitler, Lee R; Szapudi, Istvan

    2015-01-01

    FastSound is a galaxy redshift survey using the near-infrared Fiber Multi-Object Spectrograph (FMOS) mounted on the Subaru Telescope, targeting H$\\alpha$ emitters at $z \\sim 1.18$--$1.54$ down to the sensitivity limit of H$\\alpha$ flux $\\sim 2 \\times 10^{-16} \\ \\rm erg \\ cm^{-2} s^{-1}$. The primary goal of the survey is to detect redshift space distortions (RSD), to test General Relativity by measuring the growth rate of large scale structure and to constrain modified gravity models for the origin of the accelerated expansion of the universe. The target galaxies were selected based on photometric redshifts and H$\\alpha$ flux estimates calculated by fitting spectral energy distribution (SED) models to the five optical magnitudes of the Canada France Hawaii Telescope Legacy Survey (CFHTLS) Wide catalog. The survey started in March 2012, and all the observations were completed in July 2014. In total, we achieved $121$ pointings of FMOS (each pointing has a $30$ arcmin diameter circular footprint) covering $20.6...

  2. Spitzer IRAC observations of newly-discovered planetary nebulae from the Macquarie-AAO-Strasbourg H-alpha Planetary Nebula Project

    CERN Document Server

    Cohen, Martin; Green, Anne J; Murphy, Tara; Miszalski, Brent; Frew, David J; Meade, Marilyn R; Babler, Brian; Indebetouw, Remy; Whitney, Barbara A; Watson, Christer; Churchwell, Edward B; Watson, Douglas F

    2007-01-01

    We compare H-alpha, radio continuum, and Spitzer Space Telescope (SST) images of 58 planetary nebulae (PNe) recently discovered by the Macquarie-AAO-Strasbo- urg H-alpha PN Project (MASH) of the SuperCOSMOS H-alpha Survey. Using InfraRed Array Camera (IRAC) data we define the IR colors of PNe and demonstrate good isolation between these colors and those of many other types of astronomical object. The only substantive contamination of PNe in the color-color plane we illustrate is due to YSOs. However, this ambiguity is readily resolved by the unique optical characteristics of PNe and their environs. We also examine the relationships between optical and MIR morphologies from 3.6 to 8.0um and explore the ratio of mid-infrared (MIR) to radio nebular fluxes, which is a valuable discriminant between thermal and nonthermal emission. MASH emphasizes late evolutionary stages of PNe compared with previous catalogs, enabling study of the changes in MIR and radio flux that attend the aging process. Spatially integrated M...

  3. Verbal width in anabelian groups

    OpenAIRE

    Nikolov, Nikolay,

    2014-01-01

    The class $A$ of anabelian groups is defined as the collection of finite groups without abelian composition factors. We prove that the commutator word $[x_1,x_2]$ and the power word $x_1^p$ have bounded width in $A$ when $p$ is prime. By contrast the word $x^{30}$ does not have bounded width in $A$. On the other hand any given word $w$ has bounded width for those groups in $A$ whose composition factors are sufficiently large as a function of $w$. In the course of the proof w...

  4. Probabilistic Analysis of Crack Width

    Directory of Open Access Journals (Sweden)

    J. Marková

    2000-01-01

    Full Text Available Probabilistic analysis of crack width of a reinforced concrete element is based on the formulas accepted in Eurocode 2 and European Model Code 90. Obtained values of reliability index b seem to be satisfactory for the reinforced concrete slab that fulfils requirements for the crack width specified in Eurocode 2. However, the reliability of the slab seems to be insufficient when the European Model Code 90 is considered; reliability index is less than recommended value 1.5 for serviceability limit states indicated in Eurocode 1. Analysis of sensitivity factors of basic variables enables to find out variables significantly affecting the total crack width.

  5. A deterministic width function model

    Directory of Open Access Journals (Sweden)

    C. E. Puente

    2003-01-01

    Full Text Available Use of a deterministic fractal-multifractal (FM geometric method to model width functions of natural river networks, as derived distributions of simple multifractal measures via fractal interpolating functions, is reported. It is first demonstrated that the FM procedure may be used to simulate natural width functions, preserving their most relevant features like their overall shape and texture and their observed power-law scaling on their power spectra. It is then shown, via two natural river networks (Racoon and Brushy creeks in the United States, that the FM approach may also be used to closely approximate existing width functions.

  6. Cluster equivalence and graded derived equivalence

    CERN Document Server

    Amiot, Claire

    2010-01-01

    In this paper we introduce a new approach for organizing algebras of global dimension at most 2. We introduce an invariant of these algebras called cluster equivalence, based on whether their generalized cluster categories are equivalent. We are particularly interested in the question how much information about an algebra is preserved in its generalized cluster category, or, in other words, how closely two algebras are related if they have equivalent generalized cluster categories. Our approach makes use of the cluster tilting objects in the generalized cluster categories: We first observe that cluster tilting objects in generalized cluster categories are in natural bijection to cluster tilting subcategories of derived categories, and then prove a recognition theorem for the latter. Using this recognition theorem we give a precise criterion when two cluster equivalent algebras are derived equivalent. For a given algebra we further describe all the derived equivalent algebras which have the same canonical clus...

  7. On monoidal equivalences and Ann-equivalences

    OpenAIRE

    Quang, Nguyen Tien; Anh, Pham Le Hong

    2007-01-01

    In this paper, we show another proof of the problem by constructing a strict monoidal category M(C) consisting of M-functors and M-morphisms of a category C and we prove C is equivalent to it. The proof is based on a basic character of monoidal equivalences. Ideas and techniques of these proofs can been used to prove the equivalence between an Ann-category and an almost strict Ann-category.

  8. Dynamics of blue compact galaxies, as revealed by their H-alpha velocity fields I. The data, velocity fields and rotation curves

    OpenAIRE

    O?stlin, G.; Amram, P.; Masegosa, J.; Bergvall, N.; Boulesteix, J.

    1998-01-01

    Observations of six luminous blue compact galaxies (BCGs) and two star forming companion galaxies were carried out with the CIGALE scanning Fabry-Perot interferometer attached to the ESO 3.6m telescope on La Silla. The observations were made in the H-alpha emission line which is prominent in BCGs. A velocity sampling of 5 km/s and a pixel size of 0.9 arcseconds were used. In this paper we present the observations and the data together with the velocity fields and the derived...

  9. Optimizing rod window width in positron emission tomography

    International Nuclear Information System (INIS)

    A technique determines the optimal window width for orbiting rod transmission studies in positron emission tomography (PET). Windowing reduces noise in orbiting rod transmission studies. Lines-of-response (LOR) which intersect the rods generate primarily true coincidence events. LOR which pass far from the rods generate random and scatter events. Since the angular position of the orbiting rods is known in real-time, LOR which produce mostly noise are gated off. When optimally determined, the rod window width maximizes the noise equivalent counts (NEC) collected in the transmission study. Transaxial rod projection profiles of trues, randoms, and scatter produce NEC versus window width plots. For the ECAT reg-sign EXACT line of PET systems and a 20-cm water cylinder, optimal is five LOR wide

  10. On the nature of H$\\alpha$ emitters at $z \\sim 2$ from the HiZELS survey: physical properties, Ly$\\alpha$ escape fraction, and main sequence

    CERN Document Server

    Oteo, I; Ivison, R J; Smail, I; Best, P N; Cepa, J; Pérez-García, A M

    2015-01-01

    We present a detailed multi-wavelength study (from rest-frame UV to far-IR) of narrow-band (NB) selected, star-forming (SF) H$\\alpha$ emitters (HAEs) at $z \\sim 2.23$ taken from the High Redshift(Z) Emission Line Survey (HiZELS). We find that HAEs have similar SED-derived properties and colors to $sBzK$ galaxies and probe a well-defined portion of the SF population at $z \\sim 2$. This is not true for Ly$\\alpha$ emitters (LAEs), which are strongly biased towards blue, less massive galaxies (missing a significant percentage of the SF population). Combining our H$\\alpha$ observations with matched, existing Ly$\\alpha$ data we determine that the Ly$\\alpha$ escape fraction ($f_{\\rm esc}$) is low (only $\\sim$ 4.5\\% of HAEs show Ly$\\alpha$ emission) and decreases with increasing dust attenuation, UV continuum slope, stellar mass, and star formation rate (SFR). This suggests that Ly$\\alpha$ preferentially escapes from blue galaxies with low dust attenuation. However, a small population of red and massive LAEs is also ...

  11. Macroclumping as solution of the discrepancy between H{\\alpha} and P v mass loss diagnostics for O-type stars

    CERN Document Server

    Šurlan, B; Aret, A; Kubát, J; Oskinova, L M; Torres, A F

    2013-01-01

    Recent studies of O-type stars demonstrated that discrepant mass-loss rates are obtained when different diagnostic methods are employed - fitting the unsaturated UV resonance lines (e.g. P v) gives drastically lower values than obtained from the H{\\alpha} emission. Wind clumping may be the main cause for this discrepancy. In a previous paper, we have presented 3-D Monte-Carlo calculations for the formation of scattering lines in a clumped stellar wind. In the present paper we select five O-type supergiants (from O4 to O7) and test whether the reported discrepancies can be resolved this way. In the first step, the analyses start with simulating the observed spectra with Potsdam Wolf-Rayet (PoWR) non-LTE model atmospheres. The mass-loss rates are adjusted to fit best to the observed H{\\alpha} emission lines. For the unsaturated UV resonance lines (i.e. P v) we then apply our 3-D Monte-Carlo code, which can account for wind clumps of any optical depths, a non-void inter-clump medium, and a velocity dispersion in...

  12. A very young, compact bipolar H$_2$O maser outflow in the intermediate-mass star-forming LkH$\\alpha$ 234 region

    CERN Document Server

    Torrelles, J M; Estalella, R; Anglada, G; Gómez, J F; Cantó, J; Patel, N A; Trinidad, M A; Girart, J M; Carrasco-González, C; Rodríguez, L F

    2014-01-01

    We report multi-epoch VLBI H$_2$O maser observations towards the compact cluster of YSOs close to the Herbig Be star LkH$\\alpha$ 234. This cluster includes LkH$\\alpha$ 234 and at least nine more YSOs that are formed within projected distances of $\\sim$10 arcsec ($\\sim$9,000 au). We detect H$_2$O maser emission towards four of these YSOs. In particular, our VLBI observations (including proper motion measurements) reveal a remarkable very compact ($\\sim$0.2 arcsec = $\\sim$180 au), bipolar H$_2$O maser outflow emerging from the embedded YSO VLA 2. We estimate a kinematic age of $\\sim$40 yr for this bipolar outflow, with expanding velocities of $\\sim$20 km s$^{-1}$ and momentum rate $\\dot M_w V_w$ $\\simeq$ $10^{-4}-10^{-3}$ M$_{\\odot}$ yr$^{-1}$ km s$^{-1}$$\\times (\\Omega$/$4\\pi)$, powered by a YSO of a few solar masses. We propose that the outflow is produced by recurrent episodic jet ejections associated with the formation of this YSO. Short-lived episodic ejection events have previously been found towards high...

  13. A Study of the Distribution of Star-Forming Regions in Luminous Infrared Galaxies by Means of H$\\alpha$ Imaging Observations

    CERN Document Server

    Hattori, T; Ohtani, H; Sugai, H; Ishigaki, T; Sasaki, M; Hayashi, T; Ozaki, S; Ishii, M; Kawai, A

    2003-01-01

    We performed H-alpha imaging observations of 22 luminous infrared galaxies to investigate how the distribution of star-forming regions in these galaxies is related to galaxy interactions. Based on correlation diagrams between H-alpha flux and continuum emission for individual galaxies, a sequence for the distribution of star-forming regions was found: very compact (~100 pc) nuclear starbursts with almost no star-forming activity in the outer regions (type 1), dominant nuclear starbursts 1 kpc in size and a significant contribution from the outer regions (type 3), and extended starbursts with relatively faint nuclei (type 4). These classes of star-forming region were found to be strongly related to global star-forming properties such as star-formation efficiency, far-infrared color, and dust extinction. There was a clear tendency for the objects with more compact distributions of star-forming regions to show a higher star-formation efficiency and hotter far-infrared color. An appreciable fraction of the sampl...

  14. A Study of Selection Methods for H alpha Emitting Galaxies at z~1.3 for the Subaru/FMOS Galaxy Redshift Survey for Cosmology (FastSound)

    CERN Document Server

    Tonegawa, Motonari; Akiyama, Masayuki; Dalton, Gavin; Glazebrook, Karl; Iwamuro, Fumihide; Sumiyoshi, Masanao; Tamura, Naoyuki; Yabe, Kiyoto; Coupon, Jean; Goto, Tomotsugu; Spitler, Lee R

    2013-01-01

    The efficient selection of high-redshift emission galaxies is important for future large galaxy redshift surveys for cosmology. Here we describe the target selection methods for the FastSound project, a redshift survey for H alpha emitting galaxies at z=1.2-1.5 using Subaru/FMOS to measure the linear growth rate f\\sigma 8 via Redshift Space Distortion (RSD) and constrain the theory of gravity. To select ~400 target galaxies in the 0.2 deg^2 FMOS field-of-view from photometric data of CFHTLS-Wide (u*g'r'i'z'), we test several different methods based on color-color diagrams or photometric redshift estimates from spectral energy distribution (SED) fitting. We also test the improvement in selection efficiency that can be achieved by adding near-infrared data from the UKIDSS DXS (J). The success rates of H alpha detection with FMOS averaged over two observed fields using these methods are 11.3% (color-color, optical), 13.6% (color-color, optical+NIR), 17.3% (photo-z, optical), and 15.1% (photo-z, optical+NIR). Sel...

  15. A search for H$\\alpha$ emission in high-metallicity damped Lyman-$\\alpha$ systems at $z \\sim 2.4$

    CERN Document Server

    Wang, Wei-Hao; Prochaska, J Xavier

    2015-01-01

    We report on a sensitive search for redshifted H$\\alpha$ line-emission from three high-metallicity damped Ly$\\alpha$ absorbers (DLAs) at $z \\approx 2.4$ with the Near-infrared Integral Field Spectrometer (NIFS) on the Gemini-North telescope, assisted by the ALTtitude conjugate Adaptive optics for the InfraRed (ALTAIR) system with a laser guide star. Within the NIFS field-of-view, $\\approx 3.22" \\times 2.92"$ corresponding to $\\approx 25$ kpc $ \\times 23$ kpc at $z=2.4$, we detect no statistically significant line-emission at the expected redshifted H$\\alpha$ wavelengths. The measured root-mean-square noise fluctuations in $0.4"$ apertures are $1-3\\times10^{-18}$ erg s$^{-1}$ cm$^{-2}$. Our analysis of simulated, compact, line-emitting sources yields stringent limits on the star-formation rates (SFRs) of the three DLAs, $< 2.2$~M$_{\\odot}$ yr$^{-1}$ ($3\\sigma$) for two absorbers, and $< 11$~M$_{\\odot}$ yr$^{-1}$ ($3\\sigma$) for the third, at all impact parameters within $\\approx 12.5$~kpc to the quasar s...

  16. Derived equivalences between subrings

    OpenAIRE

    Chen, Yiping.

    2012-01-01

    In this paper, we construct derived equivalences between two subrings of relevant $\\Phi$-Auslander-Yoneda rings from an arbitrary short exact sequence in an abelian category. As a consequence, any short exact sequence in an abelian category gives rise to a derived equivalence between two subrings of endomorphism rings. These results generalize some methods on constructing derived equivalences.

  17. Equivalence principles and electromagnetism

    Science.gov (United States)

    Ni, W.-T.

    1977-01-01

    The implications of the weak equivalence principles are investigated in detail for electromagnetic systems in a general framework. In particular, it is shown that the universality of free-fall trajectories (Galileo weak equivalence principle) does not imply the validity of the Einstein equivalence principle. However, the Galileo principle plus the universality of free-fall rotation states does imply the Einstein principle.

  18. On the isobaric multiplet width equation

    International Nuclear Information System (INIS)

    The isobaric multiplet width equation is verified in the light of recent experimental information on masses and widths. The verification is carried out for the known level widths and the results came in support of the isobaric width equation removing all previous discrepancies. Multiplets with enough, but not complete, experimental information are also studied. (author). 3 refs, 4 tabs

  19. The narrow X-ray tail and double H-alpha tails of ESO 137-002 in Abell 3627

    CERN Document Server

    Zhang, B; Ji, L; Sarazin, C; Lin, X B; Nulsen, P E J; Roediger, E; Donahue, M; Forman, W; Jones, C; Voit, G M; Kong, X

    2013-01-01

    We present the analysis of a deep Chandra observation of a ~2L_* late-type galaxy, ESO 137-002, in the closest rich cluster A3627. The Chandra data reveal a long (>40 kpc) and narrow tail with a nearly constant width (~3 kpc) to the southeast of the galaxy, and a leading edge ~1.5 kpc from the galaxy center on the upstream side of the tail. The tail is most likely caused by the nearly edge-on stripping of ESO 137-002's ISM by ram pressure, compared to the nearly face-on stripping of ESO 137-001 discussed in our previous work. Spectral analysis of individual regions along the tail shows that the gas throughout it has a rather constant temperature, ~1 keV, very close to the temperature of the tails of ESO 137-001, if the same atomic database is used. The derived gas abundance is low (~0.2 solar with the single-kT model), an indication of the multiphase nature of the gas in the tail. The mass of the X-ray tail is only a small fraction (<5%) of the initial ISM mass of the galaxy, suggesting that the stripping ...

  20. Spreading widths of doorway states

    Energy Technology Data Exchange (ETDEWEB)

    De Pace, A., E-mail: depace@to.infn.i [Istituto Nazionale di Fisica Nucleare, Sezione di Torino, via P. Giuria 1, I-10125 Torino (Italy); Molinari, A. [Dipartimento di Fisica Teorica dell' Universita di Torino, via P. Giuria 1, I-10125 Torino (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Torino, via P. Giuria 1, I-10125 Torino (Italy); Weidenmueller, H.A. [Max-Planck-Institut fuer Kernphysik, D-69029 Heidelberg (Germany)

    2011-01-01

    As a function of energy E, the average doorway strength function S(E)-bar of a doorway state is commonly assumed to be Lorentzian in shape and characterized by two parameters, the peak energy E{sub 0} and the spreading width {Gamma}{sup {down_arrow}}. The simple picture is modified when the density of background states that couple to the doorway state changes significantly in an energy interval of size {Gamma}{sup {down_arrow}}. For that case we derive an approximate analytical expression for S(E)-bar. We test our result successfully against numerical simulations. Our result may have important implications for shell-model calculations.

  1. Dynamics of blue compact galaxies, as revealed by their $H\\alpha$ velocity fields; 1, The data, velocity fields and rotation curves

    CERN Document Server

    Östlin, G A; Masegosa, J; Bergvelt, M J; Boulesteix, J

    1998-01-01

    Observations of six luminous blue compact galaxies (BCGs) and two star forming companion galaxies were carried out with the CIGALE scanning Fabry-Perot interferometer attached to the ESO 3.6m telescope on La Silla. The observations were made in the H-alpha emission line which is prominent in BCGs. A velocity sampling of 5 km/s and a pixel size of 0.9 arcseconds were used. In this paper we present the observations and the data together with the velocity fields and the derived rotation curves. In addition we provide rough estimates of the total dynamical mass and of the ionised gas mass for each galaxy. All galaxies display rotation, but while the companion galaxies have regular velocity fields, those of the BCGs are complex and appear perturbed. This is the most extensive study to date of the optical velocity fields of BCGs. The interpretation of these results will be presented in a forthcoming paper (Paper II).

  2. Dynamics of blue compact galaxies, as revealed by their H$\\alpha$ velocity fields II. Mass models and the starburst triggering mechanism

    CERN Document Server

    Östlin, G A; Bergvall, N; Masegosa, J; Boulesteix, J; Márquez, I

    2001-01-01

    The H$\\alpha$ velocity fields of a sample of six luminous blue compact galaxies (BCGs) and two companions have been obtained by observations with a scanning Fabry-Perot interferometer. The Fabry-Perot images, velocity fields and rotations curves have been presented in a previous paper (Paper I). In general, the velocity fields are irregular and often contain secondary dynamical components, but display overall rotation. The two companions have more regular velocity fields and rotation curves. In this article we analyse the velocity fields and dynamics together with the morphology of the studied BCGs, and present detailed mass models. In addition, we model the stellar mass content by means of multicolour surface photometry and spectral evolutionary synthesis analysis. By comparison of the masses of stars and those derived from the rotation curve, we show that about half of the galaxies cannot be supported by rotation alone. The morphology and dynamics of the BCGs suggest that the starburst activity in these gal...

  3. Detonation cell widths in hydrogen-air-diluent mixtures

    International Nuclear Information System (INIS)

    In this paper I report on the influence of steam and carbon dioxide on the detonability of hydrogen-air mixtures. Data were obtained on the detonation cell width in a heated detonation tube that is 0.43 m in diameter and 13.1 m long. The detonation cell widths were correlated using a characteristic length calculated from a chemical kinetic model. The addition of either diluent to a hydrogen-air mixture increased the cell width for all equivalence ratios. For equal diluent concentrations, however, carbon dioxide not only yielded larger increases in the cell width than steam, but its efficacy relative to steam was predicted to increase with increasing concentration. The range of detonable hydrogen concentrations in a hydrogen-air mixture initially at 1 atm pressure was found to be between 11.6 percent and 74.9 percent for mixtures at 20 degree C and 9.4 percent and 76.9 percent for mixtures at 100 degree C. The detonation limit was between 38.8 percent and 40.5 percent steam for a stoichiometric hydrogen-air-steam mixture initially at 100 degree C and 1 atm. 10 refs., 4 figs., 1 tab

  4. The effect of change in width on stress distribution along the curved segments of stents

    International Nuclear Information System (INIS)

    Curved structural members are widely seen in our surroundings, such as railway supports in playgrounds resembling a c-ring structure. The common geometry of the curved member consists of a segment of a circular ring with a uniform width. The curved section is of constant width in most cardiovascular stents. This study focuses on curved strut members whose width changes along the curved segment. The location of the maximum equivalent stress varies depending on the manner in which the width changes. When the width is constant or larger toward the top, the maximum equivalent stress is developed at the top. Meanwhile, when the area is reduced toward the bottom, the largest equivalent stress is developed some distance from the top. Simple equations, based on the mechanics of materials and the theory of elasticity, were compared favorably with the results from finite element analysis. Included are elaborations of the distribution of the change of stress. The suggested strategy of changing the width, with refinements, could be applied to the optimal design of structural members, including pipes and medical devices such as stents

  5. DAG-width is PSPACE-complete

    OpenAIRE

    Amiri, Saeed Akhoondian; Kreutzer, Stephan; Rabinovich, Roman

    2014-01-01

    Berwanger et al. show that for every graph $G$ of size $n$ and DAG-width $k$ there is a DAG decomposition of width $k$ and size $n^{O(k)}$. This gives a polynomial time algorithm for determining the DAG-width of a graph for any fixed $k$. However, if the DAG-width of the graphs from a class is not bounded, such algorithms become exponential. This raises the question whether we can always find a DAG decomposition of size polynomial in $n$ as it is the case for tree width and ...

  6. A high-precision pulse-width modulator source

    International Nuclear Information System (INIS)

    A novel high-resolution pulse-width modulator (PWM) is being developed for a new digital regulator for the Advanced Photon Source power converters. The circuit features 82-ps setability over an 80-(micro)s range. Our application requires a 50-(micro)s fill-scale range; therefore the 82-ps setability is equivalent to better than 19 bits. The circuit is presently implemented as a VME module and is an integral part of the digital regulator prototype. The design concept and performance results will be presented

  7. Topics in orbit equivalence

    CERN Document Server

    Kechris, Alexander S

    2004-01-01

    This volume provides a self-contained introduction to some topics in orbit equivalence theory, a branch of ergodic theory. The first two chapters focus on hyperfiniteness and amenability. Included here are proofs of Dye's theorem that probability measure-preserving, ergodic actions of the integers are orbit equivalent and of the theorem of Connes-Feldman-Weiss identifying amenability and hyperfiniteness for non-singular equivalence relations. The presentation here is often influenced by descriptive set theory, and Borel and generic analogs of various results are discussed. The final chapter is a detailed account of Gaboriau's recent results on the theory of costs for equivalence relations and groups and its applications to proving rigidity theorems for actions of free groups.

  8. Neutron dose equivalent meter

    Science.gov (United States)

    Olsher, Richard H. (Los Alamos, NM); Hsu, Hsiao-Hua (Los Alamos, NM); Casson, William H. (Los Alamos, NM); Vasilik, Dennis G. (Los Alamos, NM); Kleck, Jeffrey H. (Menlo Park, CA); Beverding, Anthony (Foster City, CA)

    1996-01-01

    A neutron dose equivalent detector for measuring neutron dose capable of accurately responding to neutron energies according to published fluence to dose curves. The neutron dose equivalent meter has an inner sphere of polyethylene, with a middle shell overlying the inner sphere, the middle shell comprising RTV.RTM. silicone (organosiloxane) loaded with boron. An outer shell overlies the middle shell and comprises polyethylene loaded with tungsten. The neutron dose equivalent meter defines a channel through the outer shell, the middle shell, and the inner sphere for accepting a neutron counter tube. The outer shell is loaded with tungsten to provide neutron generation, increasing the neutron dose equivalent meter's response sensitivity above 8 MeV.

  9. Dust Obscuration and Metallicity at High Redshift: New Inferences from UV, H-alpha, and 8 Micron Observations of z~2 Star-Forming Galaxies

    CERN Document Server

    Reddy, Naveen A; Pettini, Max; Steidel, Charles C; Shapley, Alice E

    2010-01-01

    We use a sample of 90 spectroscopically-confirmed Lyman Break Galaxies with H-alpha and 24 micron observations to constrain the relationship between rest-frame 8 micron luminosity, L(8), and star formation rate (SFR) for L* galaxies at z~2. We find a tight correlation with 0.24 dex scatter between L8 and L(Ha)/SFR for z~2 galaxies with L(IR)~10^10 - 10^12 Lsun. Employing this relationship with a larger sample of 392 galaxies with spectroscopic redshifts, we find that the UV slope can be used to recover the dust attenuation of the vast majority of L* galaxies at z~2 to within 0.4 dex scatter using the local correlation. Separately, young galaxies with ages <100 Myr appear to follow an extinction curve that is steeper than the one found for local starburst galaxies. Therefore, such young galaxies may be significantly less dusty than inferred previously. Our results provide the first direct evidence, independent of the UV slope, for a correlation between UV and bolometric luminosity at high redshift, in the s...

  10. Study of LINER sources with broad H(alpha) emission. X-ray properties and comparision to luminous AGN and X-ray binaries

    CERN Document Server

    George, Younes; Sabra, B; Reeves, J N

    2011-01-01

    [Abridged]We study the X-ray properties of LINER sources with definite detection of a broad H(alpha) emission line in their optical spectra, LINER 1s from Ho et al. sample. These objects preferentially harbor a low luminosity active nucleus at the center and show small or no intrinsic absorption (<10^(22) cm^(-1)). We analyzed all available X-ray archived XMM-Newton and Chandra observations of 13 LINER 1s satisfying the above criterion in a systematic homogeneous way. We looked for any correlations between the X-ray properties and the intrinsic parameters of our sample of LINER 1s. An absorbed power-law gave a good fit to the spectra of 9 out of the 13 sources. A thermal component and an absorbed power-law were required in the remaining 4 sources. We found a photon index between 1.3\\pm0.2 for the hardest source and 2.4^(+0.2)_(-0.3) for the softest one with a mean value of 1.9\\pm0.2 and a dispersion sigma=0.3. The thermal component had a mean temperature kT~0.6 keV. Significant short (hours to days) time-s...

  11. Width Distributions for Convex Regular Polyhedra

    CERN Document Server

    Finch, Steven R

    2011-01-01

    The mean width is a measure on three-dimensional convex bodies that enjoys equal status with volume and surface area [Rota]. As the phrase suggests, it is the mean of a probability density f. We verify formulas for mean widths of the regular tetrahedron and the cube. Higher-order moments of f_tetra and f_cube have not been examined until now. Assume that each polyhedron has edges of unit length. We deduce that the mean square width of the regular tetrahedron is 1/3+(3+sqrt(3))/(3*pi) and the mean square width of the cube is 1+4/pi.

  12. Equivalence Testing Mobile Apps

    Directory of Open Access Journals (Sweden)

    Denzler Christoph

    2012-01-01

    Full Text Available Mobile apps are often developed and then evolved on more than one mobile operating system. For the publisher of such apps, the problem is how to ensure equivalence of the product on the various platforms, in the sense of acting equivalently with respect to a test set. In this paper we present an approach that tackles this problem from two directions: architecture and testing. First we will explain the role and pitfalls of reference architectures. Then we will present our equivalence testing framework. It is based on mocking components of the target implementation. Instead of implementing mock components for all platforms, our approach is to implement these mocks only once and run them on a central server. On the tested target device, stub components are injected that forward to their server-based counterparts. Thus the exactly same test code is applied to all platform specific implementations.

  13. Direct measurement of the W boson width

    International Nuclear Information System (INIS)

    This Letter describes a direct measurement of the W boson decay width, ?(W), using the high-mass tail of the transverse mass spectrum of W?e? decays recorded by the Collider Detector at Fermilab. We find ?(W)=2.11±0.28(stat) ± 0.16(syst) GeV and compare this direct measurement with indirect means of obtaining the width

  14. Partial nucleon escape widths of giant resonances

    International Nuclear Information System (INIS)

    Method and results of calculation of the partial nucleon escape widths of various giant resonances are presented. The comparison with relevant experimental data and the results of other theoretical approaches is given where it is possible. The partial widths for the direct proton decay of the Gamow-Teller resonance in Sn isotopes are given special attention. (orig.)

  15. Equivalent Quantum Circuits

    CERN Document Server

    Garcia-Escartin, Juan Carlos

    2011-01-01

    Quantum algorithms and protocols are often presented as quantum circuits for a better understanding. We give a list of equivalence rules which can help in the analysis and design of quantum circuits. As example applications we study quantum teleportation and dense coding protocols in terms of a simple XOR swapping circuit and give an intuitive picture of a basic gate teleportation circuit.

  16. Equivalence of Mechanical Systems.

    Czech Academy of Sciences Publication Activity Database

    Moog, C.H.; Zikmund, Ji?í; ?elikovský, S.

    Foz do Iguassu : IFAC, 2007, 1/4-4/4. [SSSC 2007. Foz do Iguassu (BR), 17.10.2007-19.10.2007] Grant ostatní: GA MŠk(CZ) LA298 Institutional research plan: CEZ:AV0Z10750506 Keywords : Mechanical Systems * State Equivalent * Embeded Dynamics Subject RIV: BC - Control Systems Theory

  17. Correspondences. Equivalence relations

    International Nuclear Information System (INIS)

    We comment on sections paragraph 3 'Correspondences' and paragraph 6 'Equivalence Relations' in chapter II of 'Elements de mathematique' by N. Bourbaki in order to simplify their comprehension. Paragraph 3 exposes the ideas of a graph, correspondence and map or of function, and their composition laws. We draw attention to the following points: 1) Adopting the convention of writting from left to right, the composition law for two correspondences (A,F,B), (U,G,V) of graphs F, G is written in full generality (A,F,B)o(U,G,V) = (A,FoG,V). It is not therefore assumed that the co-domain B of the first correspondence is identical to the domain U of the second (EII.13 D.7), (1970). 2) The axiom of choice consists of creating the Hilbert terms from the only relations admitting a graph. 3) The statement of the existence theorem of a function h such that f = goh, where f and g are two given maps having the same domain (of definition), is completed if h is more precisely an injection. Paragraph 6 considers the generalisation of equality: First, by 'the equivalence relation associated with a map f of a set E identical to (x is a member of the set E and y is a member of the set E and x:f = y:f). Consequently, every relation R(x,y) which is equivalent to this is an equivalence relation in E (symmetrical, transitive, reflexive); then R admits a graph included in E x E, etc. Secondly, by means of the Hilbert term of a relation R submitted to the equivalence. In this last case, if R(x,y) is separately collectivizing in x and y, theta(x) is not the class of objects equivalent to x for R (EII.47.9), (1970). The interest of bringing together these two subjects, apart from this logical order, resides also in the fact that the theorem mentioned in 3) can be expressed by means of the equivalence relations associated with the functions f and g. The solutions of the examples proposed reveal their simplicity

  18. Variation of Fe Kalpha line equivalent width for orbiting spot around black hole.

    Czech Academy of Sciences Publication Activity Database

    Dov?iak, Michal; Karas, Vladimír; Matt, G.; Goosmann, René

    2008-01-01

    Ro?. 79, ?. 1 (2008), s. 248-249. ISSN 0037-8720 R&D Projects: GA ?R GP205/05/P525 Institutional research plan: CEZ:AV0Z10030501 Keywords : black hole s Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  19. Perch width preferences of laying hens.

    Science.gov (United States)

    Struelens, E; Tuyttens, F A M; Ampe, B; Odberg, F; Sonck, B; Duchateau, L

    2009-07-01

    1. In order to investigate the effect of perch width on perching behaviour of laying hens, two experiments in which hens could choose between 7 different perch widths (1.5, 3.0, 4.5, 6.0, 7.5, 9.0 and 10.5 cm) were conducted. In one experiment (EXP-2P) test cages contained two long perches gradually broadening and narrowing stepwise, in the other experiment (EXP-7P) 7 separate short perches differing in width were placed in the test cages. In each experiment 12 groups of 4 hens were filmed during day and night. The behaviour and location of the hens were recorded and whether the nest box affected hen distribution over the perches was investigated. 2. During daytime, in EXP-2P, there was an increase in perch use with increasing perch width. Hens spent less time on perches of 1.5 cm wide compared to perches of 9.0 and 10.5 cm wide. In EXP-7P, the 1.5-cm wide perch was also used the least (but only the difference with 4.5-cm wide perches was statistically significant) but perch use did not increase linearly with perch width. During the night, there were no significant perch width preferences in either experiment. 3. The percentage of active behaviours (preening, walking, drinking, pecking at hen) versus passive behaviours (standing, sitting, sleeping) did not differ significantly according to perch width. 4. In EXP-7P, there was a trend for perch use to decrease with greater distances to the nest box in the morning. 5. A perch width of 1.5 cm is not recommended for laying hens. For wider perch widths, results were equivocal: they tend to support rather than challenge the widespread use of 4.5-cm wide perches in commercial units. PMID:19735010

  20. The equivalence theorem

    International Nuclear Information System (INIS)

    The equivalence theorem states that, at an energy E much larger than the vector-boson mass M, the leading order of the amplitude with longitudinally polarized vector bosons on mass shell is given by the amplitude in which these vector bosons are replaced by the corresponding Higgs ghosts. We prove the equivalence theorem and show its validity in every order in perturbation theory. We first derive the renormalized Ward identities by using the diagrammatic method. Only the Feynman-- 't Hooft gauge is discussed. The last step of the proof includes the power-counting method evaluated in the large-Higgs-boson-mass limit, needed to estimate the leading energy behavior of the amplitudes involved. We derive expressions for the amplitudes involving longitudinally polarized vector bosons for all orders in perturbation theory. The fermion mass has not been neglected and everything is evaluated in the region mf?M much-lt E much-lt mHiggs

  1. The Plane-Width of Graphs

    CERN Document Server

    Kaminski, Marcin; Milanic, Martin

    2008-01-01

    Map vertices of a graph to (not necessarily distinct) points of the plane so that two adjacent vertices are mapped at least a unit distance apart. The plane-width of a graph is the minimum diameter of the image of the vertex set over all such mappings. We establish a relation between the plane-width of a graph and its chromatic number, and connect it to other well-known areas, including the circular chromatic number and the problem of packing unit discs in the plane. We also investigate how plane-width behaves under various operations, such as homomorphism, disjoint union, complement, and the Cartesian product.

  2. Spin gated GDR widths at moderate temperatures

    Directory of Open Access Journals (Sweden)

    Mukul Ish

    2015-01-01

    Full Text Available We present the evolution of giant dipole resonance (GDR width as a function of angular momentum in the compound nucleus 144Sm in the temperature range of 1.5-2.0 MeV. The high energy ? rays emitted from the decay of excited 144Sm were measured using large NaI detector in coincidence with 4? sum spin spectrometer. GDR widths were found to comply with thermal shape fluctuation model in this temperature range over a wide range of spin. Experimental widths tend to increase rapidly at high angular momentum values.

  3. Thermal width of quarkonium from holography

    Energy Technology Data Exchange (ETDEWEB)

    Fadafan, Kazem Bitaghsir; Tabatabaei, Seyed Kamal [Shahrood University, Physics Department, Shahrood (Iran, Islamic Republic of)

    2014-04-15

    From the AdS/CFT correspondence, the effects of charge and finite 't Hooft coupling correction on the thermal width of a heavy quarkonium are investigated. To study the charge effect,we consider Maxwell charge which is interpreted as quarkmedium. In the case of finite 't Hooft coupling corrections, R{sup 4} terms and Gauss-Bonnet gravity have been considered, respectively. It is shown that these corrections affect the thermal width. It is also argued that by decreasing the 't Hooft coupling, the thermal width becomes effectively smaller. Interestingly, this is similar to analogous calculations in a weakly coupled plasma. (orig.)

  4. The equivalent parameters of the ferrite sphere in the transmission line

    Directory of Open Access Journals (Sweden)

    A. V. Kislacovsky

    1966-12-01

    Full Text Available Equivalent parameters of the ferrite sphere in the transmission line are examined. The equivalent parameters for the rectangular waveguide and coaxial supply line are calculated. The dependenence of the equivalent width line of the resonance absorption on coupling factor of the ferrite sphere with transmission is discussed. The dominant mode and the homogeneous precession is taken into consi¬deration. The experimental results for the mode H10 are adduced.

  5. CF-HiZELS, a 10 deg$^2$ emission-line survey with spectroscopic follow-up: H\\alpha, [OIII]+H\\beta\\ and [OII] luminosity functions at z=0.8, 1.4 and 2.2

    CERN Document Server

    Sobral, David; Best, Philip N; Smail, Ian; Khostovan, Ali A; Milvang-Jensen, Bo; Kim, Jae-Woo; Stott, John; Calhau, João; Nayyeri, Hooshang; Mobasher, Bahram

    2015-01-01

    We present results from the largest contiguous narrow-band survey in the near-infrared. We have used WIRCam/CFHT and the lowOH2 filter (1.187$\\pm$0.005 \\mu m) to survey ~10 deg$^2$ of contiguous extragalactic sky in the SA22 field. A total of ~6000 candidate emission-line galaxies are found. We use deep CFHTLS $ugriz$ and UKIDSS DXS $J$ and $K$ data to obtain robust photometric redshifts. We combine our data with HiZELS (COSMOS+UDS) and explore VVDS, VIPERS, KMOS and obtain our own spectroscopic follow-up with FMOS and MOSFIRE to derive large samples of high-redshift emission-line selected galaxies: 3471 H\\alpha\\ emitters at z=0.8, 1343 [OIII]+H\\beta\\ emitters at z=1.4 and 572 [OII] emitters at z=2.2. We probe co-moving volumes of >10$^6$ Mpc$^3$ and find significant over-densities, including an 8.5\\sigma\\ (spectroscopically confirmed) over-density of H\\alpha\\ emitters at z=0.81. We derive H\\alpha, [OIII]+H\\beta\\ and [OII] luminosity functions at z=0.8, 1.4 and 2.2, respectively, and present implications for ...

  6. Equivalences of coisotropic submanifolds

    DEFF Research Database (Denmark)

    Schaetz, Florian; Zambon, Marco

    2014-01-01

    We study the role that Hamiltonian and symplectic diffeomorphisms play in the deformation problem of coisotropic submanifolds. We prove that the action by Hamiltonian diffeomorphisms corresponds to the gauge-action of the $L_\\infty$-algebra of Oh and Park. Moreover we introduce the notion of extended gauge-equivalence and show that in the case of Oh and Park's $L_\\infty$-algebra one recovers the action of symplectic isotopies on coisotropic submanifolds. Finally, we consider the transversally integrable case in detail.

  7. Appropriate energy window width for gamma camera

    Directory of Open Access Journals (Sweden)

    Jabbari N

    2004-06-01

    Full Text Available Introduction: Scatter radiation is one of the major sources of error in nuclear medicine data processing. Different methods of scatter correction have been introduced in order to improve the quality of data. However the best method is to avoid recording of scatter photons in acquisition. The only difference between scattered and non-scattered photons is the energy. Pulse height analyzer is the only option available to discriminate primary photons from scattered ones. Energy resolution of the gamma camera is gradually improving consequently the energy window width has to be decreased accordingly. In this study we tried to determine the most appropriate energy window width for present gamma camera systems. Methods and Materials: Since it is not possible to retrieve the data spectrum from the most of the gamma camera systems, a simple method was developed to extract the data from the image of the energy spectrum. Using a scatter phantom different level of scatter and count rate were generated and corresponding energy spectrum data were analyzed. It was assumed that around the peak of the spectrum, the primary photons obey a Gaussian distribution. Results: The data were analyzed using three different methods. All methods prove that the optimum window width regarding the present gamma camera energy resolution is 15%. At this level, the scattered radiation is decreased to 5%. In comparison to the conventional widow width of 20%, the sensitivity does not change dramatically. Conclusion: At the present, for most gamma camera, the energy window width of 20% is recommended. However occasionally energy window width of 15% and 25% are also used. In this study the energy spectrum at different levels of scatter were analyzed and the most suitable energy window width was found to be 15% for the gamma camera having approximate energy resolution of 11%. At this window setting the scatter decreases to 5% of the total counts recorded. Visually the quality of the images dose not improves significantly. However accuracy of data quantification improve significantly.

  8. Establishing Substantial Equivalence: Proteomics

    Science.gov (United States)

    Lovegrove, Alison; Salt, Louise; Shewry, Peter R.

    Wheat is a major crop in world agriculture and is consumed after processing into a range of food products. It is therefore of great importance to determine the consequences (intended and unintended) of transgenesis in wheat and whether genetically modified lines are substantially equivalent to those produced by conventional plant breeding. Proteomic analysis is one of several approaches which can be used to address these questions. Two-dimensional PAGE (2D PAGE) remains the most widely available method for proteomic analysis, but is notoriously difficult to reproduce between laboratories. We therefore describe methods which have been developed as standard operating procedures in our laboratory to ensure the reproducibility of proteomic analyses of wheat using 2D PAGE analysis of grain proteins.

  9. Inflation and Global Equivalence

    CERN Document Server

    Martin, G

    2001-01-01

    This article investigates an extension of General Relativity based upon a class of lifted metrics on the cotangent bundle of space-time. The dynamics of the theory is determined by a fixed section of the cotangent bundle, representing the momentum of a fluid flow, and Einstein's equations for the fluid applied to the induced space-time metric on the submanifold of the cotangent bundle defined by the image of the section. This construction is formally analogous to the extension of Galilean Relativity by Special Relativity, and is shown to reduce to General Relativity as the gravitational constant approaches zero. By examining the consequences of the model for homogeneous cosmologies, it is demonstrated that this construction globalizes the equivalence principle, in that, the perfect fluid model of Special Relativity is sufficient to predict both the inflationary and the current era.

  10. Equivalent nozzles in thermomechanical problems

    International Nuclear Information System (INIS)

    Axisymmetric nozzle-sphere geometry models for finite element analysis are described which are equivalent to three-dimensional nozzle-cylinder intersections in the sense of giving the same maximum equivalent stress. This equivalence is obtained by varying the radius of the sphere. Both mechanical and thermal load cases typical of actual operating conditions are considered, although it is shown that it is not possible to use the same equivalent model on both types of load. The implications are that cheaper computing costs could be obtained for expensive non-linear calculations provided the loss in accuracy of the results through using the equivalence model was not too severe. (author)

  11. Stochastic model of the width function

    Science.gov (United States)

    Veneziano, Daniele; Moglen, Glenn E.; Furcolo, Pierluigi; Iacobellis, Vito

    2000-04-01

    A new class of probabilistic models of the width function, based on so-called iterated random pulse (IRP) processes, is proposed. IRP processes reproduce the main characteristics of empirical width functions (nonnegativity, nonstationarity, and power law decay of the spectrum) and require few and easily accessible parameters. IRP models are based on a simple conceptualization of the geometrical structure of river basins and exploit in a natural way the self-similarity of natural channel networks. A result that is derived from the IRP representation is that the exponent ? of Hack's law, L ˜ A?, and the exponent ? of the power spectral density of the width function, S(?) ˜ |?|-?, are related as ? = 1/?. Empirical values of ? are typically in the range 1.8-2.0 and are consistent with this theoretical result and the usual range of ?.

  12. Preequilibrium escape widths of giant resonances

    Science.gov (United States)

    Roos, M. O.; Dias, H.; Rodriguez, O.; Teruya, N.; Hussein, M. S.

    2002-08-01

    In this work we present a calculation of the 2p-2h preequilibrium escape width of giant resonances for the nuclei 40Ca, 90Zr, and 208Pb. The problem studied here involves an excited nucleus in the 1p-1h configuration, evolving to the 2p-2h configuration with the 1p in the continuum. The theoretical approach used for our calculations is based on the statistical multistep compound theory of Feshbach, Kerman, and Koonin (FKK) and on the particle-hole state densities given by Obložinský. Our calculations show that although different state densities supply a similar result for the damping width, the escape width is strongly dependent on the nuclei, on the binding energy of the emitted nucleon, and the excitation energy of the giant resonance.

  13. High Fin Width Mosfet Using Gaa Structure

    Directory of Open Access Journals (Sweden)

    S.L.Tripathi

    2012-11-01

    Full Text Available This paper describes the design and optimization of gate-all-around (GAA MOSFETs structures. The optimum value of Fin width and Fin height are investigated for superior subthreshold behavior. Also the performance of Fin shaped GAA with gate oxide HfO2 are simulated and compared with conventional gate oxide SiO2 for the same structure. As a result, it was observed that the GAA with high K dielectric gate oxide has more possibility to optimize the Fin width with improved performance. All the simulations are performed on 3-D TCAD device simulator.

  14. The Higgs Boson Width is Adjustable

    OpenAIRE

    Chivukula, R. Sekhar; Dugan, Michael J.; Golden, Mitchell

    1994-01-01

    We show that it is possible to construct models in which the width of the Higgs boson is arbitrary - either smaller or larger than a standard model Higgs boson of the same mass. There are no new fields into which the Higgs boson decays. Instead, the coupling of the Higgs boson to the gauge bosons is adjusted. We construct and analyze weakly--coupled models with arbitrary--width Higgs bosons to investigate the phenomenology one might find in a strongly interacting model. In a...

  15. Directed Width Measures and Monotonicity of Directed Graph Searching

    OpenAIRE

    Kaiser, ?ukasz; Kreutzer, Stephan; Rabinovich, Roman; Siebertz, Sebastian

    2014-01-01

    We consider generalisations of tree width to directed graphs, that attracted much attention in the last fifteen years. About their relative strength with respect to "bounded width in one measure implies bounded width in the other" many problems remain unsolved. Only some results separating directed width measures are known. We give an almost complete picture of this relation. For this, we consider the cops and robber games characterising DAG-width and directed tree width (up...

  16. Concurrent Supermassive Black Hole and Galazy Growth: Linking Environment and Nuclear Activity in Zeta Equals 2.23 H Alpha Emitters

    Science.gov (United States)

    Lehmer, B. D.; Lucy, A. B.; Alexander, D. M.; Best, P. N.; Geach, J. E.; Harrison, C. M.; Hornschemeier, A. E.; Matsuda, Y.; Mullaney, J. R.; Smail, Ian; Sobral, D.; Swinbank, A. M.

    2013-01-01

    We present results from an approximately equal 100 ks Chandra observation of the 2QZ Cluster 1004+00 structure at z = 2.23 (hereafter 2QZ Clus). 2QZ Clus was originally identified as an overdensity of four optically-selected QSOs at z = 2.23 within a 15 × 15 arcmin square region. Narrow-band imaging in the near-IR (within the K band) revealed that the structure contains an additional overdensity of 22 z = 2.23 H alpha-emitting galaxies (HAEs), resulting in 23 unique z = 2.23 HAEs/QSOs (22 within the Chandra field of view). Our Chandra observations reveal that three HAEs in addition to the four QSOs harbor powerfully accreting supermassive black holes (SMBHs), with 2-10 keV luminosities of approximately equal (8-60) × 10(exp 43) erg s(exp-1) and X-ray spectral slopes consistent with unobscured active galactic nucleus (AGN). Using a large comparison sample of 210 z = 2.23 HAEs in the Chandra-COSMOS field (C-COSMOS), we find suggestive evidence that the AGN fraction increases with local HAE galaxy density. The 2QZ Clus HAEs reside in a moderately overdense environment (a factor of approximately equal 2 times over the field), and after excluding optically-selected QSOs, we find that the AGN fraction is a factor of approximately equal 3.5(+3.8/ -2.2) times higher than C-COSMOS HAEs in similar environments. Using stacking analyses of the Chandra data and Herschel SPIRE observations at 250micrometers, we respectively estimate mean SMBH accretion rates ( M(BH)) and star formation rates (SFRs) for the 2QZ Clus and C-COSMOS samples. We find that the mean 2QZ Clus HAE stacked X-ray luminosity is QSO-like (L(2-10 keV) approximately equal [6-10] × 10(exp 43) erg s(exp -1)), and the implied M(BH)/SFR approximately equal (1.6-3.2) × 10(exp -3) is broadly consistent with the local M(BH)/Stellar Mass relation and z approximately equal 2 X-ray selected AGN. In contrast, the C-COSMOS HAEs are on average an order of magnitude less X-ray luminous and have M(BH)/SFR approximately equal (0.2-0.4) × 10(exp -3), somewhat lower than the local MBH/M relation, but comparable to that found for z approximately equal 1-2 star-forming galaxies with similar mean X-ray luminosities. We estimate that a periodic QSO phase with duty cycle approximately 2%-8% would be sufficient to bring star-forming galaxies onto the local M(BH)/Stellar Mass relation. This duty cycle is broadly consistent with the observed C-COSMOS HAE AGN fraction (Approximately equal 0.4%-2.3%) for powerful AGN with LX approximately greater than 10(exp 44) erg s(exp -1). Future observations of 2QZ Clus will be needed to identify key factors responsible for driving the mutual growth of the SMBHs and galaxies.

  17. The ratio of the interzygomatic width with mesiodistal width of maxillary anterior teeth

    Directory of Open Access Journals (Sweden)

    Savabi O

    2002-07-01

    Full Text Available Esthetics is one of the prosthetic treatment goals. Correct selection of anterior teeth, regarding size and appearance, results in a successful treatment. The goal of the present research was to investigate the relationship between interzygomatic width and maxillary anterior teeth width in order to find a better determinant for artificial anterior teeth selection. In this study, the interzygomatic width and maxillary central incisors width and also the width of six maxillary anterior- teeth, in 71 subjects (29females and 42 males were measured. The results showed a significant difference in maxillary anterior teeth width, comparing men and women, (P<0.05. These measurement in people under study, are less than Europeans. The interzygomatic width was also more in men than women (PO.05, which is, less than of European race. The ratio between interzygomatic and central maxillary incisor width was 15:1 which is less than 16:1 that is used in clinic. Thus, it is recommended to pay more attention to anterior teeth selection, especially in young patients.

  18. EQUIVALENCE VERSUS NON-EQUIVALENCE IN ECONOMIC TRANSLATION

    OpenAIRE

    Cristina, CHIFANE

    2012-01-01

    This paper aims at highlighting the fact that “equivalence” represents a concept worth revisiting and detailing upon when tackling the translation process of economic texts both from English into Romanian and from Romanian into English. Far from being exhaustive, our analysis will focus upon the problems arising from the lack of equivalence at the word level. Consequently, relevant examples from the economic field will be provided to account for the following types of non-equivalence at w...

  19. Nonlocal potentials and resonances of narrow width

    International Nuclear Information System (INIS)

    This paper discusses resonances of narrow width in the context of bound states embedded in the continuum spectrum of nonlocal potentials. Feshbach's theory of nuclear reactions leads directly to resonance theory, and we base our discussion here on the techniques he developed for shifting nuclear many-body aspects into effective single-particle nonlocal potentials. In our formulation, the many-body state of the compound nucleus is represented by a single-particle state. The basis for our discussion is a two channel model of a resonance of zero width, with a continuum bound state originating from the coupling of a bound state to the single-particle scattering state. We give a specific example of a model which leads to an arbitrarily narrow (nonzero width) resonance, and demonstrate that the width of the resonance produced by breaking the continuum bound state is proportional to (?-1)2, where the parameter ? is such that ? = 1 corresponds to the condition necessary for the existence of a continuum bound state

  20. Bounding the Higgs boson width through interferometry.

    Science.gov (United States)

    Dixon, Lance J; Li, Ye

    2013-09-13

    We study the change in the diphoton-invariant-mass distribution for Higgs boson decays to two photons, due to interference between the Higgs resonance in gluon fusion and the continuum background amplitude for gg???. Previously, the apparent Higgs mass was found to shift by around 100 MeV in the standard model in the leading-order approximation, which may potentially be experimentally observable. We compute the next-to-leading-order QCD corrections to the apparent mass shift, which reduce it by about 40%. The apparent mass shift may provide a way to measure, or at least bound, the Higgs boson width at the Large Hadron Collider through "interferometry." We investigate how the shift depends on the Higgs width, in a model that maintains constant Higgs boson signal yields. At Higgs widths above 30 MeV, the mass shift is over 200 MeV and increases with the square root of the width. The apparent mass shift could be measured by comparing with the ZZ* channel, where the shift is much smaller. It might be possible to measure the shift more accurately by exploiting its strong dependence on the Higgs transverse momentum. PMID:24074073

  1. Towards Automating Grammar Equivalence Checking

    OpenAIRE

    Madhavan, Ravichandhran; Mayer, Mikael; Gulwani, Sumit; Kuncak, Viktor

    2015-01-01

    We consider from practical perspective the (generally undecidable) problem of checking equivalence of context-free grammars. We present both techniques for proving equivalence, as well as techniques for finding counter-examples that establish non-equivalence. Among the key building blocks of our approach is a novel algorithm for efficiently enumerating and sampling words and parse trees from arbitrary context-free grammars; the algorithm supports polynomial time random access to words belong...

  2. Equivalence Principle and Gravitational Redshift

    International Nuclear Information System (INIS)

    We investigate leading order deviations from general relativity that violate the Einstein equivalence principle in the gravitational standard model extension. We show that redshift experiments based on matter waves and clock comparisons are equivalent to one another. Consideration of torsion balance tests, along with matter-wave, microwave, optical, and Moessbauer clock tests, yields comprehensive limits on spin-independent Einstein equivalence principle-violating standard model extension terms at the 10-6 level.

  3. Equivalence Principle and Gravitational Redshift

    OpenAIRE

    Hohensee, Michael A.; Chu, Steven; Peters, Achim; Mueller, Holger

    2011-01-01

    We investigate leading order deviations from general relativity that violate the Einstein equivalence principle in the gravitational standard model extension. We show that redshift experiments based on matter waves and clock comparisons are equivalent to one another. Consideration of torsion balance tests, along with matter wave, microwave, optical, and M\\"ossbauer clock tests, yields comprehensive limits on spin-independent Einstein equivalence principle-violating standard ...

  4. Model-Checking Process Equivalences

    OpenAIRE

    Martin Lange; Etienne Lozes; Manuel Vargas Guzmán

    2012-01-01

    Process equivalences are formal methods that relate programs and system which, informally, behave in the same way. Since there is no unique notion of what it means for two dynamic systems to display the same behaviour there are a multitude of formal process equivalences, ranging from bisimulation to trace equivalence, categorised in the linear-time branching-time spectrum. We present a logical framework based on an expressive modal fixpoint logic which is capable of defini...

  5. Model-Checking Process Equivalences

    Directory of Open Access Journals (Sweden)

    Martin Lange

    2012-10-01

    Full Text Available Process equivalences are formal methods that relate programs and system which, informally, behave in the same way. Since there is no unique notion of what it means for two dynamic systems to display the same behaviour there are a multitude of formal process equivalences, ranging from bisimulation to trace equivalence, categorised in the linear-time branching-time spectrum. We present a logical framework based on an expressive modal fixpoint logic which is capable of defining many process equivalence relations: for each such equivalence there is a fixed formula which is satisfied by a pair of processes if and only if they are equivalent with respect to this relation. We explain how to do model checking, even symbolically, for a significant fragment of this logic that captures many process equivalences. This allows model checking technology to be used for process equivalence checking. We show how partial evaluation can be used to obtain decision procedures for process equivalences from the generic model checking scheme.

  6. Isomorphism Testing for Graphs of Bounded Rank Width

    OpenAIRE

    Grohe, Martin; Schweitzer, Pascal

    2015-01-01

    We give an algorithm that, for every fixed k, decides isomorphism of graphs of rank width at most k in polynomial time. As the clique width of a graph is bounded in terms of its rank width, we also obtain a polynomial time isomorphism test for graph classes of bounded clique width.

  7. Joint H-alpha and X-ray Observations of Massive X-ray Binaries. I. The B-Supergiant System LS I +65 010 = 2S 0114+650

    CERN Document Server

    Grundstrom, E D; Gies, D R; Huang, W; McSwain, M V; Raghavan, D; Riddle, R L; Subasavage, J P; Wingert, D W; Levine, A M; Remillard, R A

    2006-01-01

    We report on a three year spectroscopic monitoring program of the H-alpha emission in the massive X-ray binary LS I +65 010 = 2S 0114+650, which consists of a B-supergiant and a slowly rotating X-ray pulsar. We present revised orbital elements that yield a period of P=11.5983 +/- 0.0006 d and confirm that the orbit has a non-zero eccentricity e=0.18 +/- 0.05. The H-alpha emission profile is formed in the base of the wind of the B-supergiant primary, and we show how this spectral feature varies on timescales that are probably related to the rotational period of the B-supergiant. We also examine the X-ray fluxes from the Rossi X-ray Timing Explorer All-Sky Monitor instrument, and we show that the X-ray orbital light curve has a maximum at periastron and a minimum at the inferior conjunction of the B-supergiant. We also show that the wind emission strength and the high energy X-ray flux appear to vary in tandem on timescales of approximately a year.

  8. CMS presents new boundary of Higgs width

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    At last year's Moriond conference, CERN physicists announced the retirement of the "Higgs-like" particle and the arrival of "boson, Higgs boson". Now, one year later, at the same session in the same conference, physicists are back with more exciting news about the famed particle. This time: the best constraint yet of the Higgs Boson “width”, a parameter that determines the particle’s lifetime.   Rencontres de Moriond 2014. As a key indicator for new physics, the Higgs “width” has long been on the LHC "to-do" list. Now less than two years post-discovery, the CMS experiment has gotten the closest yet to pinning it down, constraining the parameter to < 17 MeV with 95% confidence. This result is some two orders of magnitude better than previous limits: stronger evidence that this boson looks like the Standard Model Higgs boson. "It's been exciting to see how wel...

  9. The Width of the Colour Flux Tube

    OpenAIRE

    Caselle, M.; F. Gliozzi; Magnea, U.; Vinti, S.

    1994-01-01

    We discuss and rederive in a general way the logarithmic growth of the mean squared width of the colour flux tube as a function of the interquark separation. Recent data on 3D $Z_2$ gauge theory, combined with high precision data on the interface physics of the 3D Ising model fit nicely this behaviour over a range of more than two orders of magnitude.

  10. Are there any good digraph width measures?

    CERN Document Server

    Ganian, Robert; Kneis, Joachim; Meister, Daniel; Obdržálek, Jan; Rossmanith, Peter; Sikdar, Somnath

    2010-01-01

    Several different measures for digraph width have appeared in the last few years. However, none of them shares all the "nice" properties of treewidth: First, being \\emph{algorithmically useful} i.e. admitting polynomial-time algorithms for all $\\MS1$-definable problems on digraphs of bounded width. And, second, having nice \\emph{structural properties} i.e. being monotone under taking subdigraphs and some form of arc contractions. As for the former, (undirected) $\\MS1$ seems to be the least common denominator of all reasonably expressive logical languages on digraphs that can speak about the edge/arc relation on the vertex set.The latter property is a necessary condition for a width measure to be characterizable by some version of the cops-and-robber game characterizing the ordinary treewidth. Our main result is that \\emph{any reasonable} algorithmically useful and structurally nice digraph measure cannot be substantially different from the treewidth of the underlying undirected graph. Moreover, we introduce \\...

  11. Biologic Width - The No Encroachment Zone

    Directory of Open Access Journals (Sweden)

    Hari Krishna Reddy S

    2010-12-01

    Full Text Available Dentistry of modern era is dominated by restorative procedures which are carried out to meet the demands of not only function but also esthetics. The dentist is having a narrow room of flexibility to wander in order to achieve a good esthetic restoration which is fully functional, the design of preparation and the technique sensitive fabrication form one side of the coin and establishing a harmonious margin for a crown on abutment forms the other side of the coin when trying to insert a fixed prosthetic restoration for replacing missing teeth, the phenomenon of biologic width was less understood till very recently but the growing clinical experience and better diagnostic skills of today has helped us to understand the intricacies of this concept and the need for its maintenance, the violation of which leads to the ultimate failure of the prosthesis. This article attempts to explain the ways of diagnosing biologic width violation, the care needed to exert when preparing a teeth to receive a crown and exactly deciding where to place the margins of the crown to avoid biologic width violation

  12. Measurement of the total width, the electronic width, and the mass of the ?(10580) resonance

    Science.gov (United States)

    Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Gaillard, J.-M.; Hicheur, A.; Karyotakis, Y.; Lees, J. P.; Tisserand, V.; Zghiche, A.; Palano, A.; Pompili, A.; Chen, J. C.; Qi, N. D.; Rong, G.; Wang, P.; Zhu, Y. S.; Eigen, G.; Ofte, I.; Stugu, B.; Abrams, G. S.; Borgland, A. W.; Breon, A. B.; Brown, D. N.; Button-Shafer, J.; Cahn, R. N.; Charles, E.; Day, C. T.; Gill, M. S.; Gritsan, A. V.; Groysman, Y.; Jacobsen, R. G.; Kadel, R. W.; Kadyk, J.; Kerth, L. T.; Kolomensky, Yu. G.; Kukartsev, G.; Leclerc, C.; Lynch, G.; Merchant, A. M.; Mir, L. M.; Oddone, P. J.; Orimoto, T. J.; Pripstein, M.; Roe, N. A.; Ronan, M. T.; Shelkov, V. G.; Telnov, A. V.; Wenzel, W. A.; Ford, K.; Harrison, T. J.; Hawkes, C. M.; Morgan, S. E.; Watson, A. T.; Fritsch, M.; Goetzen, K.; Held, T.; Koch, H.; Lewandowski, B.; Pelizaeus, M.; Steinke, M.; Boyd, J. T.; Chevalier, N.; Cottingham, W. N.; Kelly, M. P.; Latham, T. E.; Wilson, F. F.; Cuhadar-Donszelmann, T.; Hearty, C.; Mattison, T. S.; McKenna, J. A.; Thiessen, D.; Kyberd, P.; Teodorescu, L.; Blinov, V. E.; Bukin, A. D.; Druzhinin, V. P.; Golubev, V. B.; Ivanchenko, V. N.; Kravchenko, E. A.; Onuchin, A. P.; Serednyakov, S. I.; Skovpen, Yu. I.; Solodov, E. P.; Yushkov, A. N.; Best, D.; Bruinsma, M.; Chao, M.; Eschrich, I.; Kirkby, D.; Lankford, A. J.; Mandelkern, M.; Mommsen, R. K.; Roethel, W.; Stoker, D. P.; Buchanan, C.; Hartfiel, B. L.; Gary, J. W.; Shen, B. C.; Wang, K.; del Re, D.; Hadavand, H. K.; Hill, E. J.; Macfarlane, D. B.; Paar, H. P.; Rahatlou, Sh.; Sharma, V.; Berryhill, J. W.; Campagnari, C.; Dahmes, B.; Levy, S. L.; Long, O.; Lu, A.; Mazur, M. A.; Richman, J. D.; Verkerke, W.; Beck, T. W.; Eisner, A. M.; Heusch, C. A.; Lockman, W. S.; Schalk, T.; Schmitz, R. E.; Schumm, B. A.; Seiden, A.; Spradlin, P.; Williams, D. C.; Wilson, M. G.; Albert, J.; Chen, E.; Dubois-Felsmann, G. P.; Dvoretskii, A.; Hitlin, D. G.; Narsky, I.; Piatenko, T.; Porter, F. C.; Ryd, A.; Samuel, A.; Yang, S.; Jayatilleke, S.; Mancinelli, G.; Meadows, B. T.; Sokoloff, M. D.; Abe, T.; Blanc, F.; Bloom, P.; Chen, S.; Clark, P. J.; Ford, W. T.; Nauenberg, U.; Olivas, A.; Rankin, P.; Smith, J. G.; Zhang, L.; Chen, A.; Harton, J. L.; Soffer, A.; Toki, W. H.; Wilson, R. J.; Zeng, Q. L.; Altenburg, D.; Brandt, T.; Brose, J.; Colberg, T.; Dickopp, M.; Feltresi, E.; Hauke, A.; Lacker, H. M.; Maly, E.; Müller-Pfefferkorn, R.; Nogowski, R.; Otto, S.; Petzold, A.; Schubert, J.; Schubert, K. R.; Schwierz, R.; Spaan, B.; Sundermann, J. E.; Bernard, D.; Bonneaud, G. R.; Brochard, F.; Grenier, P.; Schrenk, S.; Thiebaux, Ch.; Vasileiadis, G.; Verderi, M.; Bard, D. J.; Khan, A.; Lavin, D.; Muheim, F.; Playfer, S.; Andreotti, M.; Azzolini, V.; Bettoni, D.; Bozzi, C.; Calabrese, R.; Cibinetto, G.; Luppi, E.; Negrini, M.; Piemontese, L.; Sarti, A.; Treadwell, E.; Baldini-Ferroli, R.; Calcaterra, A.; de Sangro, R.; Finocchiaro, G.; Patteri, P.; Piccolo, M.; Zallo, A.; Buzzo, A.; Capra, R.; Contri, R.; Crosetti, G.; Vetere, M. Lo; Macri, M.; Monge, M. R.; Passaggio, S.; Patrignani, C.; Robutti, E.; Santroni, A.; Tosi, S.; Bailey, S.; Brandenburg, G.; Morii, M.; Won, E.; Dubitzky, R. S.; Langenegger, U.; Bhimji, W.; Bowerman, D. A.; Dauncey, P. D.; Egede, U.; Gaillard, J. R.; Morton, G. W.; Nash, J. A.; Taylor, G. P.; Grenier, G. J.; Mallik, U.; Cochran, J.; Crawley, H. B.; Lamsa, J.; Meyer, W. T.; Prell, S.; Rosenberg, E. I.; Yi, J.; Davier, M.; Grosdidier, G.; Höcker, A.; Laplace, S.; Le Diberder, F.; Lepeltier, V.; Lutz, A. M.; Petersen, T. C.; Plaszczynski, S.; Schune, M. H.; Tantot, L.; Wormser, G.; Cheng, C. H.; Lange, D. J.; Simani, M. C.; Wright, D. M.; Bevan, A. J.; Coleman, J. P.; Fry, J. R.; Gabathuler, E.; Gamet, R.; Parry, R. J.; Payne, D. J.; Sloane, R. J.; Touramanis, C.; Back, J. J.; Cormack, C. M.; Harrison, P. F.; Mohanty, G. B.; Brown, C. L.; Cowan, G.; Flack, R. L.; Flaecher, H. U.; Green, M. G.; Marker, C. E.; McMahon, T. R.; Ricciardi, S.; Salvatore, F.; Vaitsas, G.; Winter, M. A.; Brown, D.; Davis, C. L.; Allison, J.; Barlow, N. R.; Barlow, R. J.; Hart, P. A.; Hodgkinson, M. C.; Lafferty, G. D.; Lyon, A. J.; Williams, J. C.; Farbin, A.; Hulsbergen, W. D.; Jawahery, A.; Kovalskyi, D.; Lae, C. K.; Lillard, V.; Roberts, D. A.; Blaylock, G.; Dallapiccola, C.; Flood, K. T.; Hertzbach, S. S.; Kofler, R.; Koptchev, V. B.; Moore, T. B.; Saremi, S.; Staengle, H.; Willocq, S.; Cowan, R.; Sciolla, G.; Taylor, F.; Yamamoto, R. K.; Mangeol, D. J.; Patel, P. M.; Robertson, S. H.; Lazzaro, A.; Palombo, F.; Bauer, J. M.; Cremaldi, L.; Eschenburg, V.; Godang, R.; Kroeger, R.; Reidy, J.; Sanders, D. A.; Summers, D. J.; Zhao, H. W.; Brunet, S.; Côté, D.; Taras, P.; Nicholson, H.; Cavallo, N.; Fabozzi, F.; Gatto, C.; Lista, L.; Monorchio, D.; Paolucci, P.; Piccolo, D.; Sciacca, C.

    2005-08-01

    We present a measurement of the parameters of the ?(10580) resonance based on a dataset collected with the BABAR detector at the SLAC PEP-II asymmetric B factory. We measure the total width ?tot=(20.7±1.6±2.5) MeV, the electronic partial width ?ee=(0.321±0.017±0.029) keV and the mass M=(10579.3±0.4±1.2) MeV/c2.

  13. Modified model of neutron resonance widths distribution. Results of total gamma-widths approximation

    International Nuclear Information System (INIS)

    Functional dependences of probability to observe given ?n0 value and algorithms for determination of the most probable magnitudes of the modified model of resonance parameter distributions were used for analysis of the experimental data on the total radiative widths of neutron resonances. As in the case of neutron widths, precise description of the ?? spectra requires a superposition of three and more probability distributions for squares of the random normally distributed values with different nonzero average and nonunit dispersion. This result confirms the preliminary conclusion obtained earlier at analysis of ?n0 that practically in all 56 tested sets of total gamma widths there are several groups noticeably differing from each other by the structure of their wave functions. In addition, it was determined that radiative widths are much more sensitive than the neutron ones to resonance wave functions structure. Analysis of early obtained neutron reduced widths distribution parameters for 157 resonance sets in the mass region of nuclei 35 ? A ? 249 was also performed. It was shown that the experimental values of widths can correspond with high probability to superposition of several expected independent distributions with their nonzero mean values and nonunit dispersion

  14. Pre-torsors and equivalences

    CERN Document Server

    Böhm, G; B\\"ohm, Gabriella; Brzezinski, Tomasz

    2006-01-01

    Properties of (most general) non-commutative torsors or $A$-$B$ torsors are analysed. Starting with pre-torsors it is shown that they are equivalent to a certain class of Galois extensions of algebras by corings. It is then concluded that every faithfully flat unital pre-torsor admits a (left and right) flat (bimodule) connection. It is shown that a class of faithfully flat pre-torsors induces equivalences between categories of comodules of associated corings. It is then proven that $A$-$B$ torsors correspond to monoidal functors (and, under some additional conditions, equivalences) between categories of comodules of bialgebroids.

  15. Statistical analysis of partial reduced width distributions

    International Nuclear Information System (INIS)

    The aim of this study was to develop rigorous methods for analysing experimental event distributions according to a law in chi2 and to check if the number of degrees of freedom ? is compatible with the value 1 for the reduced neutron width distribution. Two statistical methods were used (the maximum-likelihood method and the method of moments); it was shown, in a few particular cases, that ? is compatible with 1. The difference between ? and 1, if it exists, should not exceed 3%. These results confirm the validity of the compound nucleus model

  16. Width of the charge distribution in fission

    International Nuclear Information System (INIS)

    The width of the charge distribution (for a fixed mass split) observed in nuclear fission can be estimated by assuming that it is associated with fluctuations in the collective coordinate corresponding to the flow of neutrons and protons back and forth through the neck connecting the nascent fragments. The possibility that different dynamical trajectories (one-body and viscous damping) can be distinguished is investigated for fission of 236U. It is found that, although the predicted charge dispersion is quite close to the observed value, the curves for the two trajectories are so close that a choice between the trajectories cannot be made. 2 figures

  17. Measurements of Higgs Properties (mass, spin, width)

    CERN Document Server

    Demers, Sarah; The ATLAS collaboration

    2015-01-01

    The results of ATLAS and CMS on the measurement of the Higgs boson mass and of various studies of its spin parity and width are presented. The analyses are based on pp collision data collected at centre-of-mass energies of 7 and 8 TeV, corresponding to integrated luminosities of approximately 5/fb and 20/fb per experiment, respectively. The main Higgs boson decay channels used for these studies are H???,H?ZZ?4? and H?WW?2?2?, where the ?s are electrons or muons.

  18. Optical spectra line width in quantum dots.

    Czech Academy of Sciences Publication Activity Database

    Král, Karel; Menšík, Miroslav

    2009-01-01

    Ro?. 6, Suppl. (2009), 513/1-513/2. ISSN 1708-5284. [International Conference on Composites or Nano Engineering/17./. Honolulu, 26.07.2009-01.08.2009] R&D Projects: GA MŠk ME 866; GA ?R GA202/07/0643 Institutional research plan: CEZ:AV0Z10100520; CEZ:AV0Z40500505 Keywords : quantum dot s * line width * optical spectra Subject RIV: BM - Solid Matter Physics ; Magnetism http://wjoe.hebeu.edu.cn/ICCE-17%20proceedings%20Hawaii%20USA/Kral,%20K.%20%28Prague,%20Czech%20Rep.%29%20%20513.pdf

  19. Graph Operations on Clique-Width Bounded Graphs

    CERN Document Server

    Gurski, F

    2007-01-01

    In this paper we survey the behavior of various graph operations on the graph parameters clique-width and NLC-width. We give upper and lower bounds for the clique-width and NLC-width of the modified graphs in terms of the clique-width and NLC-width of the involved graphs. Therefor we consider the binary graph operations join, co-join, sum, difference, products, corona, substitution, and 1-sum, and the unary graph operations quotient, subgraph, edge complement, bipartite edge complement, power of graphs, switching, local complementation, edge addition, edge subdivision, vertex identification, and vertex addition.

  20. Equivalency Detectives: Fractions and Decimals!

    Science.gov (United States)

    Maribel Magdaleno

    2012-07-17

    This is a lesson intended to reinforce students' ability to find equivalent fractions and decimals. The lesson requires prior essential vocabulary knowledge, and a basic understanding of converting fractions to decimals and decimals to fractions (specifically tenths and hundredths).

  1. Model equivalence of PRISM programs

    OpenAIRE

    Cussens, James

    2008-01-01

    The problem of deciding the probability model equivalence of two PRISM programs is addressed. In the finite case this problem can be solved (albeit slowly) using techniques from emph{algebraic statistics}, specifically the computation of elimination ideals and Gr"{o}bner bases. A very brief introduction to algebraic statistics is given. Consideration is given to cases where shortcuts to proving/disproving model equivalence are available.

  2. Equivalence Problem in Compositional Models.

    Czech Academy of Sciences Publication Activity Database

    Kratochvíl, Václav

    Praha : University of Economics Prague, 2009 - (Kroupa, T.; Vejnarová, J.), s. 133-143 ISBN 978-80-245-1543-4. [WUPES 2009. Liblice (CZ), 19.09.2009-23.09.2009] Institutional research plan: CEZ:AV0Z10750506 Keywords : Compositional model * Equivalence problem Subject RIV: BA - General Mathematics http://library.utia.cas.cz/separaty/2009/MTR/kratochvil-equivalence problem in compositional models .pdf

  3. Enumerating ODE Equivalent Homogeneous Networks

    CERN Document Server

    Windsor, Alistair J

    2011-01-01

    We give an simple criterion for ODE equivalence in identical edge homogeneous coupled cell networks. This allows us to give a simple proof of Theorem 10.3 of Aquiar and Dias "Minimal Coupled Cell Networks", which characterizes minimal identical edge homogeneous coupled cell networks. Using our criterion we give a formula for counting homogeneous coupled cell networks up to ODE equivalence. Our criterion is purely graph theoretic and makes no explicit use of linear algebra.

  4. Universal decay rule for reduced widths

    CERN Document Server

    Delion, D S

    2009-01-01

    Emission processes including $\\alpha$-decay, heavy cluster decays, proton and di-proton emission are analyzed in terms of the well known factorisation between the penetrability and reduced width. By using a shifted harmonic oscilator plus Coulomb cluster-daughter interaction it is possible to derive a linear relation between the logarithm of the reduced width squared and the fragmentation potential, defined as the difference between the Coulomb barrier and Q-value. This relation is fulfilled with a good accuracy for transitions between ground states, as well as for most $\\alpha$-decays to low lying $2^+$ excited states. The well known Viola-Seaborg rule, connecting half lives with the Coulomb parameter and the product between fragment charge numbers, as well as the Blendowke scalling rule connecting the spectroscopic factor with the mass number of the emitted cluster, can be easily understood in terms of the fragmentation potential. It is shown that the recently evidenced two regions in the dependence of redu...

  5. Measurement of the total width, the electronic width, and the mass of the Upsilon(10580) resonance

    OpenAIRE

    Boutigny, D; Eigen, G.; Brown, DN; Button-Shafer, J.; Gritsan, AV; Kerth, LT; LeClerc, C.(Lawrence Berkeley National Laboratory and University of California, 94720, Berkeley, California, USA); Lynch, G.(Lawrence Berkeley National Laboratory and University of California, 94720, Berkeley, California, USA); Roe, NA; Ronan, MT; Shelkov, VG; Fritsch, M; Boyd, JT; Mattison, TS; Kyberd, P.

    2005-01-01

    We present a measurement of the parameters of the $\\Upsilon(10580)$ resonance based on a dataset collected with the BABAR detector at the SLAC PEP-II asymmetric $B$ factory. We measure the total width $\\Gamma_{\\rm tot}$ to be $(20.7\\pm1.6\\pm2.5) {\\rm MeV}$, the electronic partial width $\\Gamma_{ee} = (0.321\\pm0.017\\pm0.029) {\\rm keV}$ and the mass $M = (10579.3\\pm0.4\\pm1.2) {\\rm MeV/c^2}$.

  6. Lake Basin Fetch and Maximum Length/Width

    Minnesota Department of Natural Resources — Linear features representing the Fetch, Maximum Length and Maximum Width of a lake basin. Fetch, maximum length and average width are calcuated from the lake...

  7. Frequency dependence of pulse width for 150 radio normal pulsars

    CERN Document Server

    Chen, J L

    2014-01-01

    The frequency dependence of pulse width is studied for 150 normal pulsars, mostly selected from the European Pulsar Network, of which the multi-frequency 10% pulse widths can be well fitted with the Thorsett relationship $W_{10}=A\

  8. Using tissue equivalent proportional counters to determine dose equivalent

    International Nuclear Information System (INIS)

    Tissue equivalent proportional counters (TEPCs) have been used in the laboratory for over 30 years to determine neutron dose in mixed radiation fields, but they are seldom used by operational health physicists. But a number of TEPC-based instruments are being developed in Europe and in the United States. The purpose of this paper is: to introduce operational health physicists to tissue equivalent proportional counters, to examine some of the algorithms used to convert data from TEPCs into dose equivalent, to examine how TEPC measurements meet the requirements of DOE Order 5480.11 (DOE 1988) and 10CFR20, and to examine some of the TEPC-based instruments that are available. Many operational health physicists are not familiar with the concept of microdosimetry and the specialized terms that are used in analyzing the data from TEPCs, so a brief discussion is included. At present, quality factors are defined in terms of linear energy transfer, but TEPCs measure lineal energy

  9. Formulae for partial widths derived from the Lindblad equation

    OpenAIRE

    Selstø, Sølve

    2012-01-01

    A method for calculating partial widths of auto-ionizing states is proposed. It combines either a complex absorbing potential or exterior complex scaling with the Lindblad equation. The corresponding classical rate equations are reproduced, and the trace conservation inherent in the Lindblad equation ensures that the partial widths sums up to the total width of the initial auto-ionizing state.

  10. Direct Measurement of the W Boson Width

    Science.gov (United States)

    Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T.; Aguilo, E.; Ahsan, M.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G. A.; Ancu, L. S.; Andeen, T.; Anzelc, M. S.; Aoki, M.; Arnoud, Y.; Arov, M.; Arthaud, M.; Askew, A.; Åsman, B.; Atramentov, O.; Avila, C.; Backusmayes, J.; Badaud, F.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barberis, E.; Barfuss, A.-F.; Bargassa, P.; Baringer, P.; Barreto, J.; Bartlett, J. F.; Bassler, U.; Bauer, D.; Beale, S.; Bean, A.; Begalli, M.; Begel, M.; Belanger-Champagne, C.; Bellantoni, L.; Benitez, J. A.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bezzubov, V. A.; Bhat, P. C.; Bhatnagar, V.; Blazey, G.; Blessing, S.; Bloom, K.; Boehnlein, A.; Boline, D.; Bolton, T. A.; Boos, E. E.; Borissov, G.; Bose, T.; Brandt, A.; Brock, R.; Brooijmans, G.; Bross, A.; Brown, D.; Bu, X. B.; Buchholz, D.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Burnett, T. H.; Buszello, C. P.; Calfayan, P.; Calpas, B.; Calvet, S.; Cammin, J.; Carrasco-Lizarraga, M. A.; Carrera, E.; Carvalho, W.; Casey, B. C. K.; Castilla-Valdez, H.; Chakrabarti, S.; Chakraborty, D.; Chan, K. M.; Chandra, A.; Cheu, E.; Cho, D. K.; Cho, S. W.; Choi, S.; Choudhary, B.; Christoudias, T.; Cihangir, S.; Claes, D.; Clutter, J.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M.-C.; Cutts, D.; ?wiok, M.; Das, A.; Davies, G.; de, K.; de Jong, S. J.; de La Cruz-Burelo, E.; Devaughan, K.; Déliot, F.; Demarteau, M.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Diehl, H. T.; Diesburg, M.; Dominguez, A.; Dorland, T.; Dubey, A.; Dudko, L. V.; Duflot, L.; Duggan, D.; Duperrin, A.; Dutt, S.; Dyshkant, A.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Eno, S.; Escalier, M.; Evans, H.; Evdokimov, A.; Evdokimov, V. N.; Facini, G.; Ferapontov, A. V.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fortner, M.; Fox, H.; Fuess, S.; Gadfort, T.; Galea, C. F.; Garcia-Bellido, A.; Gavrilov, V.; Gay, P.; Geist, W.; Geng, W.; Gerber, C. E.; Gershtein, Y.; Gillberg, D.; Ginther, G.; Golovanov, G.; Gómez, B.; Goussiou, A.; Grannis, P. D.; Greder, S.; Greenlee, H.; Greenwood, Z. D.; Gregores, E. M.; Grenier, G.; Gris, Ph.; Grivaz, J.-F.; Grohsjean, A.; Grünendahl, S.; Grünewald, M. W.; Guo, F.; Guo, J.; Gutierrez, G.; Gutierrez, P.; Haas, A.; Haefner, P.; Hagopian, S.; Haley, J.; Hall, I.; Hall, R. E.; Han, L.; Harder, K.; Harel, A.; Hauptman, J. M.; Hays, J.; Hebbeker, T.; Hedin, D.; Hegeman, J. G.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-de La Cruz, I.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoang, T.; Hobbs, J. D.; Hoeneisen, B.; Hohlfeld, M.; Hossain, S.; Houben, P.; Hu, Y.; Hubacek, Z.; Huske, N.; Hynek, V.; Iashvili, I.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffré, M.; Jain, S.; Jakobs, K.; Jamin, D.; Jesik, R.; Johns, K.; Johnson, C.; Johnson, M.; Johnston, D.; Jonckheere, A.; Jonsson, P.; Juste, A.; Kajfasz, E.; Karmanov, D.; Kasper, P. A.; Katsanos, I.; Kaushik, V.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Khatidze, D.; Kirby, M. H.; Kirsch, M.; Klima, B.; Kohli, J. M.; Konrath, J.-P.; Kozelov, A. V.; Kraus, J.; Kuhl, T.; Kumar, A.; Kupco, A.; Kur?a, T.; Kuzmin, V. A.; Kvita, J.; Lacroix, F.; Lam, D.; Lammers, S.; Landsberg, G.; Lebrun, P.; Lee, H. S.; Lee, W. M.; Leflat, A.; Lellouch, J.; Li, L.; Li, Q. Z.; Lietti, S. M.; Lim, J. K.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, Y.; Liu, Z.; Lobodenko, A.; Lokajicek, M.; Love, P.; Lubatti, H. J.; Luna-Garcia, R.; Lyon, A. L.; Maciel, A. K. A.; Mackin, D.; Mättig, P.; Magaña-Villalba, R.; Mal, P. K.; Malik, S.; Malyshev, V. L.; Maravin, Y.; Martin, B.; McCarthy, R.; McGivern, C. L.; Meijer, M. M.; Melnitchouk, A.; Mendoza, L.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Meyer, A.; Meyer, J.; Mondal, N. K.; Montgomery, H. E.; Moore, R. W.; Moulik, T.; Muanza, G. S.; Mulhearn, M.; Mundal, O.; Mundim, L.; Nagy, E.; Naimuddin, M.; Narain, M.; Neal, H. A.; Negret, J. P.; Neustroev, P.; Nilsen, H.; Nogima, H.; Novaes, S. F.; Nunnemann, T.; Obrant, G.; Ochando, C.; Onoprienko, D.; Orduna, J.; Oshima, N.; Osman, N.; Osta, J.; Otec, R.; Otero Y Garzón, G. J.; Owen, M.; Padilla, M.; Padley, P.; Pangilinan, M.; Parashar, N.; Park, S.-J.; Park, S. K.; Parsons, J.; Partridge, R.; Parua, N.; Patwa, A.; Penning, B.; Perfilov, M.; Peters, K.; Peters, Y.; Pétroff, P.; Piegaia, R.; Piper, J.; Pleier, M.-A.; Podesta-Lerma, P. L. M.; Podstavkov, V. M.; Pogorelov, Y.; Pol, M.-E.; Polozov, P.; Popov, A. V.; Prewitt, M.; Protopopescu, S.; Qian, J.; Quadt, A.; Quinn, B.; Rakitine, A.; Rangel, M. S.; Ranjan, K.; Ratoff, P. N.; Renkel, P.; Rich, P.; Rijssenbeek, M.

    2009-12-01

    We present a direct measurement of the width of the W boson using the shape of the transverse mass distribution of W?e? candidate events. Data from approximately 1fb-1 of integrated luminosity recorded at s=1.96TeV by the D0 detector at the Fermilab Tevatron pp¯ collider are analyzed. We use the same methods and data sample that were used for our recently published W boson mass measurement, except for the modeling of the recoil, which is done with a new method based on a recoil library. Our result, 2.028±0.072GeV, is in agreement with the predictions of the standard model.

  11. Direct measurement of the W boson width.

    Science.gov (United States)

    Abazov, V M; Abbott, B; Abolins, M; Acharya, B S; Adams, M; Adams, T; Aguilo, E; Ahsan, M; Alexeev, G D; Alkhazov, G; Alton, A; Alverson, G; Alves, G A; Ancu, L S; Andeen, T; Anzelc, M S; Aoki, M; Arnoud, Y; Arov, M; Arthaud, M; Askew, A; Asman, B; Atramentov, O; Avila, C; BackusMayes, J; Badaud, F; Bagby, L; Baldin, B; Bandurin, D V; Banerjee, S; Barberis, E; Barfuss, A-F; Bargassa, P; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Beale, S; Bean, A; Begalli, M; Begel, M; Belanger-Champagne, C; Bellantoni, L; Benitez, J A; Beri, S B; Bernardi, G; Bernhard, R; Bertram, I; Besançon, M; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Blazey, G; Blessing, S; Bloom, K; Boehnlein, A; Boline, D; Bolton, T A; Boos, E E; Borissov, G; Bose, T; Brandt, A; Brock, R; Brooijmans, G; Bross, A; Brown, D; Bu, X B; Buchholz, D; Buehler, M; Buescher, V; Bunichev, V; Burdin, S; Burnett, T H; Buszello, C P; Calfayan, P; Calpas, B; Calvet, S; Cammin, J; Carrasco-Lizarraga, M A; Carrera, E; Carvalho, W; Casey, B C K; Castilla-Valdez, H; Chakrabarti, S; Chakraborty, D; Chan, K M; Chandra, A; Cheu, E; Cho, D K; Cho, S W; Choi, S; Choudhary, B; Christoudias, T; Cihangir, S; Claes, D; Clutter, J; Cooke, M; Cooper, W E; Corcoran, M; Couderc, F; Cousinou, M-C; Cutts, D; Cwiok, M; Das, A; Davies, G; De, K; de Jong, S J; De La Cruz-Burelo, E; DeVaughan, K; Déliot, F; Demarteau, M; Demina, R; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Dominguez, A; Dorland, T; Dubey, A; Dudko, L V; Duflot, L; Duggan, D; Duperrin, A; Dutt, S; Dyshkant, A; Eads, M; Edmunds, D; Ellison, J; Elvira, V D; Enari, Y; Eno, S; Escalier, M; Evans, H; Evdokimov, A; Evdokimov, V N; Facini, G; Ferapontov, A V; Ferbel, T; Fiedler, F; Filthaut, F; Fisher, W; Fisk, H E; Fortner, M; Fox, H; Fuess, S; Gadfort, T; Galea, C F; Garcia-Bellido, A; Gavrilov, V; Gay, P; Geist, W; Geng, W; Gerber, C E; Gershtein, Y; Gillberg, D; Ginther, G; Golovanov, G; Gómez, B; Goussiou, A; Grannis, P D; Greder, S; Greenlee, H; Greenwood, Z D; Gregores, E M; Grenier, G; Gris, Ph; Grivaz, J-F; Grohsjean, A; Grünendahl, S; Grünewald, M W; Guo, F; Guo, J; Gutierrez, G; Gutierrez, P; Haas, A; Haefner, P; Hagopian, S; Haley, J; Hall, I; Hall, R E; Han, L; Harder, K; Harel, A; Hauptman, J M; Hays, J; Hebbeker, T; Hedin, D; Hegeman, J G; Heinson, A P; Heintz, U; Hensel, C; Heredia-De La Cruz, I; Herner, K; Hesketh, G; Hildreth, M D; Hirosky, R; Hoang, T; Hobbs, J D; Hoeneisen, B; Hohlfeld, M; Hossain, S; Houben, P; Hu, Y; Hubacek, Z; Huske, N; Hynek, V; Iashvili, I; Illingworth, R; Ito, A S; Jabeen, S; Jaffré, M; Jain, S; Jakobs, K; Jamin, D; Jesik, R; Johns, K; Johnson, C; Johnson, M; Johnston, D; Jonckheere, A; Jonsson, P; Juste, A; Kajfasz, E; Karmanov, D; Kasper, P A; Katsanos, I; Kaushik, V; Kehoe, R; Kermiche, S; Khalatyan, N; Khanov, A; Kharchilava, A; Kharzheev, Y N; Khatidze, D; Kirby, M H; Kirsch, M; Klima, B; Kohli, J M; Konrath, J-P; Kozelov, A V; Kraus, J; Kuhl, T; Kumar, A; Kupco, A; Kurca, T; Kuzmin, V A; Kvita, J; Lacroix, F; Lam, D; Lammers, S; Landsberg, G; Lebrun, P; Lee, H S; Lee, W M; Leflat, A; Lellouch, J; Li, L; Li, Q Z; Lietti, S M; Lim, J K; Lincoln, D; Linnemann, J; Lipaev, V V; Lipton, R; Liu, Y; Liu, Z; Lobodenko, A; Lokajicek, M; Love, P; Lubatti, H J; Luna-Garcia, R; Lyon, A L; Maciel, A K A; Mackin, D; Mättig, P; Magaña-Villalba, R; Mal, P K; Malik, S; Malyshev, V L; Maravin, Y; Martin, B; McCarthy, R; McGivern, C L; Meijer, M M; Melnitchouk, A; Mendoza, L; Menezes, D; Mercadante, P G; Merkin, M; Meyer, A; Meyer, J; Mondal, N K; Montgomery, H E; Moore, R W; Moulik, T; Muanza, G S; Mulhearn, M; Mundal, O; Mundim, L; Nagy, E; Naimuddin, M; Narain, M; Neal, H A; Negret, J P; Neustroev, P; Nilsen, H; Nogima, H; Novaes, S F; Nunnemann, T; Obrant, G; Ochando, C; Onoprienko, D; Orduna, J; Oshima, N; Osman, N; Osta, J; Otec, R; Otero y Garzón, G J; Owen, M; Padilla, M; Padley, P; Pangilinan, M; Parashar, N; Park, S-J; Park, S K; Parsons, J; Partridge, R; Parua, N; Patwa, A; Penning, B; Perfilov, M; Peters, K; Peters, Y; Pétroff, P; Piegaia, R; Piper, J; Pleier, M-A; Podesta-Lerma, P L M; Podstavkov, V M; Pogorelov, Y; Pol, M-E; Polozov, P; Popov, A V; Prewitt, M; Protopopescu, S; Qian, J; Quadt, A; Quinn, B; Rakitine, A; Rangel, M S; Ranjan, K; Ratoff, P N; Renkel, P; Rich, P; Rijssenbeek, M; Ripp-Baudot, I; Rizatdinova, F; Robinson, S; Rominsky, M; Royon, C; Rubinov, P; Ruchti, R; Safronov, G; Sajot, G; Sánchez-Hernández, A; Sanders, M P; Sanghi, B; Savage, G; Sawyer, L; Scanlon, T; Schaile, D; Schamberger, R D; Scheglov, Y; Schellman, H; Schliephake, T; Schlobohm, S; Schwanenberger, C; Schwienhorst, R; Sekaric, J; Severini, H; Shabalina, E; Shamim, M; Shary, V; Shchukin, A A; Shivpuri, R K; Siccardi, V; Simak, V; Sirotenko, V; Skubic, P; Slattery, P; Smirnov, D; Snow, G R; Snow, J; Snyder, S; Söldner-Rembold, S

    2009-12-01

    We present a direct measurement of the width of the W boson using the shape of the transverse mass distribution of W --> enu candidate events. Data from approximately 1 fb(-1) of integrated luminosity recorded at square root of s = 1.96 TeV by the D0 detector at the Fermilab Tevatron pp collider are analyzed. We use the same methods and data sample that were used for our recently published W boson mass measurement, except for the modeling of the recoil, which is done with a new method based on a recoil library. Our result, 2.028 +/- 0.072 GeV, is in agreement with the predictions of the standard model. PMID:20366142

  12. Constraining the divertor heat width in ITER

    International Nuclear Information System (INIS)

    A model is developed which constrains heat width, ?r based on global power balance, momentum conservation, pedestal stability and sheath heat transmission. The model relies on measurements of the ratio of separatrix to pedestal pressure; a ratio ?5% is found to be expected for ITER. Applying this model indicates a constraint that the allowed ?r ? 10–30 mm for ITER if the divertor is in the high-recycling regime as expected (T r ? 1–3 mm requires a separatrix pressure approximately equal to the top pedestal pressure in violation of physical reasoning and the concept of a pedestal. A weaker constraint is applied in the model that upstream separatrix temperature simultaneously satisfies power balance. The constrained model cannot satisfy power balance with ?r r ? 5 mm requires divertor plasma temperature >100 eV, a condition which would have very negative consequences for the divertor, but has never been observed experimentally

  13. Direct measurement of the W boson width

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, V.M.; /Dubna, JINR; Abbott, B.; /Oklahoma U.; Abolins, M.; /Michigan State U.; Acharya, B.S.; /Tata Inst.; Adams, M.; /Illinois U., Chicago; Adams, T.; /Florida State U.; Aguilo, E.; /Alberta U. /Simon Fraser U. /McGill U.; Ahsan, M.; /Kansas State U.; Alexeev, G.D.; /Dubna, JINR; Alkhazov, G.; /St. Petersburg, INP; Alton, A.; /Michigan U. /Northeastern U.

    2009-09-01

    We present a direct measurement of the width of the W boson using the shape of the transverse mass distribution of W {yields} e{nu} candidates selected in 1 fb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron collider in p{bar p} collisions at {radical}s = 1.96 TeV. We use the same methods and data sample that were used for our recently published W boson mass measurement, except for the modeling of the recoil, which is done with a new method based on a recoil library. Our result, 2.028 {+-} 0.072 GeV, is in agreement with the predictions of the standard model and is the most precise direct measurement result from a single experiment to date.

  14. Symmetries of Dynamically Equivalent Theories

    Science.gov (United States)

    Gitman, D. M.; Tyutin, I. V.

    2006-03-01

    A natural and very important development of constrained system theory is a detail study of the relation between the constraint structure in the Hamiltonian formulation with specific features of the theory in the Lagrangian formulation, especially the relation between the constraint structure with the symmetries of the Lagrangian action. An important preliminary step in this direction is a strict demonstration, and this is the aim of the present article, that the symmetry structures of the Hamiltonian action and of the Lagrangian action are the same. This proved, it is sufficient to consider the symmetry structure of the Hamiltonian action. The latter problem is, in some sense, simpler because the Hamiltonian action is a first-order action. At the same time, the study of the symmetry of the Hamiltonian action naturally involves Hamiltonian constraints as basic objects. One can see that the Lagrangian and Hamiltonian actions are dynamically equivalent. This is why, in the present article, we consider from the very beginning a more general problem: how the symmetry structures of dynamically equivalent actions are related. First, we present some necessary notions and relations concerning infinitesimal symmetries in general, as well as a strict definition of dynamically equivalent actions. Finally, we demonstrate that there exists an isomorphism between classes of equivalent symmetries of dynamically equivalent actions.

  15. Symmetries of dynamically equivalent theories

    Scientific Electronic Library Online (English)

    D. M., Gitman; I. V., Tyutin.

    2006-03-01

    Full Text Available A natural and very important development of constrained system theory is a detail study of the relation between the constraint structure in the Hamiltonian formulation with specific features of the theory in the Lagrangian formulation, especially the relation between the constraint structure with th [...] e symmetries of the Lagrangian action. An important preliminary step in this direction is a strict demonstration, and this is the aim of the present article, that the symmetry structures of the Hamiltonian action and of the Lagrangian action are the same. This proved, it is sufficient to consider the symmetry structure of the Hamiltonian action. The latter problem is, in some sense, simpler because the Hamiltonian action is a first-order action. At the same time, the study of the symmetry of the Hamiltonian action naturally involves Hamiltonian constraints as basic objects. One can see that the Lagrangian and Hamiltonian actions are dynamically equivalent. This is why, in the present article, we consider from the very beginning a more general problem: how the symmetry structures of dynamically equivalent actions are related. First, we present some necessary notions and relations concerning infinitesimal symmetries in general, as well as a strict definition of dynamically equivalent actions. Finally, we demonstrate that there exists an isomorphism between classes of equivalent symmetries of dynamically equivalent actions.

  16. Equivalent linearization of nonlinear forces

    Science.gov (United States)

    Meng, Guang; Xue, Zhongqing

    1987-07-01

    A method used for equivalent linearization of the two orthogonal squeeze-film forces is extended here to the general case of n degrees of freedom and n components of nonlinear forces, and the expressions for equivalent linear coefficients are derived. Nonlinear forces can be linearized by the methods of Fourier expansion, active and reactive powers, or mean-square error. The n components of nonlinear forces can all be expressed formally as the sum of an average force, a linear spring force, and a linear damping force. This paper also gives a flow chart for calculating the steady-state responses of a nonlinear system with many degrees of freedom, using the method of equivalent linearization. The resulting saving in computation time is demonstrated by a numerical example of a flexible rotor-bearing system with a noncentralized squeeze-film damper.

  17. Narrow-width mechanism of a=5 ?-state

    International Nuclear Information System (INIS)

    Narrow-width mechanism of ?5H is discussed by calculating conversion widths to all its possible decay channels. Since the conversion processes have small reaction Q values, the three- and four- body decays are strongly suppressed owing to small phase volumes available. Decay widths to the two-body channels are significantly reduced by the distortion of emitted-particle waves. This mechanism brings about a narrow width of ?5H. The total width is estimated to be 0.87 MeV, in which the largest contribution comes from the decay into the ?4H*+? channel. (author)

  18. Global synchronization of parallel processors using clock pulse width modulation

    Science.gov (United States)

    Chen, Dong; Ellavsky, Matthew R.; Franke, Ross L.; Gara, Alan; Gooding, Thomas M.; Haring, Rudolf A.; Jeanson, Mark J.; Kopcsay, Gerard V.; Liebsch, Thomas A.; Littrell, Daniel; Ohmacht, Martin; Reed, Don D.; Schenck, Brandon E.; Swetz, Richard A.

    2013-04-02

    A circuit generates a global clock signal with a pulse width modification to synchronize processors in a parallel computing system. The circuit may include a hardware module and a clock splitter. The hardware module may generate a clock signal and performs a pulse width modification on the clock signal. The pulse width modification changes a pulse width within a clock period in the clock signal. The clock splitter may distribute the pulse width modified clock signal to a plurality of processors in the parallel computing system.

  19. EQUIVALENCE VERSUS NON-EQUIVALENCE IN ECONOMIC TRANSLATION

    Directory of Open Access Journals (Sweden)

    Cristina, Chifane

    2012-01-01

    Full Text Available This paper aims at highlighting the fact that “equivalence” represents a concept worth revisiting and detailing upon when tackling the translation process of economic texts both from English into Romanian and from Romanian into English. Far from being exhaustive, our analysis will focus upon the problems arising from the lack of equivalence at the word level. Consequently, relevant examples from the economic field will be provided to account for the following types of non-equivalence at word level: culturespecific concepts; the source language concept is not lexicalised in the target language; the source language word is semantically complex; differences in physical and interpersonal perspective; differences in expressive meaning; differences in form; differences in frequency and purpose of using specific forms and the use of loan words in the source text. Likewise, we shall illustrate a number of translation strategies necessary to deal with the afore-mentioned cases of non-equivalence: translation by a more general word (superordinate; translation by a more neutral/less expressive word; translation by cultural substitution; translation using a loan word or loan word plus explanation; translation by paraphrase using a related word; translation by paraphrase using unrelated words; translation by omission and translation by illustration.

  20. [Treatment of meconium ileus equivalent].

    Science.gov (United States)

    Lambrecht, W; Weinland, G; Koch, G; Gaedicke, G

    1978-07-01

    A 12-year old boy with mucoviscidosis developed a mechanical obstruction of the small intestine. The diagnosis of a meconium ileus equivalent was made and a conservative treatment was started. After this treatment failed, a laparotomy was performed which verified the diagnosis of a meconium ileus equivalent. It was possible to move the inspissated feces inside the terminal ileum into the ascending colon. The postoperative course was uneventful. The etiology, differential diagnosis, and both conservative and operative treatment of this complication of the mucoviscidosis are discussed. PMID:679786

  1. GAP WIDTH STUDY IN LASER BUTT-WELDING

    DEFF Research Database (Denmark)

    Gong, Hui; Olsen, Flemming Ove

    1999-01-01

    In this paper the maximum allowable gap width in laser butt-welding is intensively studied. The gap width study (GWS) is performed on the material of SST of W1.4401 (AISI 316) under various welding conditions, which are the gap width : 0.00-0.50 mm, the welding speed : 0.5-2.0 m/min, the laser power : 2 and 2.6 kW and the focal point position : 0 and -1.2 mm. Quality of all the butt welds are destructively tested according to ISO 13919-1.Influences of the variable process parameters to the maximum allowable gap width are observed as (1) the maximum gap width is inversely related to the welding speed, (2) the larger laser power leads to the bigger maximum allowable gap width and (3) the focal point position has very little influence on the maximum gap width.

  2. On C$^2$-smooth Surfaces of Constant Width

    CERN Document Server

    Guilfoyle, Brendan

    2007-01-01

    A number of results for C$^2$-smooth surfaces of constant width in Euclidean 3-space ${\\mathbb{E}}^3$ are obtained. In particular, an integral inequality for constant width surfaces is established. This is used to prove that the ratio of volume to cubed width of a constant width surface is reduced by shrinking it along its normal lines. We also give a characterization of surfaces of constant width that have rational support function. Our techniques, which are complex differential geometric in nature, allow us to construct explicit smooth surfaces of constant width in ${\\mathbb{E}}^3$, and their focal sets. They also allow for easy construction of tetrahedrally symmetric surfaces of constant width.

  3. Step width alters iliotibial band strain during running.

    Science.gov (United States)

    Meardon, Stacey A; Campbell, Samuel; Derrick, Timothy R

    2012-11-01

    This study assessed the effect of step width during running on factors related to iliotibial band (ITB) syndrome. Three-dimensional (3D) kinematics and kinetics were recorded from 15 healthy recreational runners during overground running under various step width conditions (preferred and at least +/- 5% of their leg length). Strain and strain rate were estimated from a musculoskeletal model of the lower extremity. Greater ITB strain and strain rate were found in the narrower step width condition (p Polynomial contrasts revealed a linear increase in both ITB strain and strain rate with decreasing step width. We conclude that relatively small decreases in step width can substantially increase ITB strain as well as strain rates. Increasing step width during running, especially in persons whose running style is characterized by a narrow step width, may be beneficial in the treatment and prevention of running-related ITB syndrome. PMID:23259236

  4. Equivalences to the triangulation conjecture

    OpenAIRE

    Randall, Duane

    2002-01-01

    We utilize the obstruction theory of Galewski-Matumoto-Stern to derive equivalent formulations of the Triangulation Conjecture. For example, every closed topological manifold M^n with n > 4 can be simplicially triangulated if and only if the two distinct combinatorial triangulations of RP^5 are simplicially concordant.

  5. CCD photonic system for rail width measurement

    Science.gov (United States)

    Ryabichenko, Roman B.; Popov, Sergey V.; Smoleva, Olga S.

    1999-10-01

    At present, in Moscow metro a track inspection vehicle, defectoscope and portable measurement instruments are used to measure the rail profile and the condition of track. The track inspection vehicle measures 8 parameters, such as rail height, width, lip flow, cant, gauge and rail identification. The main drawback of the existing track control devices is a contact mode of measurement that does not provide required accuracy during the movement of the track inspection vehicle. This drawback can be eliminated using the non-contact photonic system (NPS). NPS consists of four special digital CCD-cameras and four lasers (two cameras and two lasers on each rail), rigidly connected together and mounted underneath the rail inspection vehicle in such a manner that corners of vision and distances from the cameras up to the head of the rail remain fixed during the movement. A special processor is included at the output of each camera. It performs preliminary processing of the stripe image on the appropriate side of a rail and then codes (compresses) and transfers data to central computer. The central computer executes the rail profile restoration and its comparison with the pattern of the rail on the particular section of the track.

  6. Quantum Equivalent Magnetic Fields that Are Not Classically Equivalent

    CERN Document Server

    Gordon, Carolyn; Schueth, Dorothee; Webb, David

    2010-01-01

    We construct pairs of compact K\\"ahler-Einstein manifolds $(M_i,g_i,\\omega_i)$ ($i=1,2)$ of complex dimension $n$ with the following properties: The canonical line bundle $L_i=\\bigwedge^n T^*M_i$ has Chern class $[\\omega_i/2\\pi]$, and for each integer $k$ the tensor powers $L_1^{\\otimes k}$ and $L_2^{\\otimes k}$ are isospectral for the bundle Laplacian associated with the canonical connection, while $M_1$ and $M_2$ -- and hence $T^*M_1$ and $T^*M_2$ -- are not homeomorphic. In the context of geometric quantization, we interpret these examples as magnetic fields which are quantum equivalent but not classically equivalent. Moreover, we construct many examples of line bundles $L$, pairs of potentials $Q_1$, $Q_2$ on the base manifold, and pairs of connections $\

  7. Martin's conjecture, arithmetic equivalence, and countable Borel equivalence relations

    OpenAIRE

    Marks, Andrew; Slaman, Theodore; Steel, John

    2011-01-01

    There is a fascinating interplay and overlap between recursion theory and descriptive set theory. A particularly beautiful source of such interaction has been Martin's conjecture on Turing invariant functions. This longstanding open problem in recursion theory has connected to many problems in descriptive set theory, particularly in the theory of countable Borel equivalence relations. In this paper, we shall give an overview of some work that has been done on Martin's conj...

  8. ?onsolidation and creepof subfoundations having finite widths ???????????? ? ?????????? ????????? ??????????? ???????? ??????

    Directory of Open Access Journals (Sweden)

    Ter-Martirosyan Zaven Grigor’evich

    2013-04-01

    Full Text Available The authors formulate and solve the problem of consolidation and creep of saturated clay subfoundations exposed to localized loads (the two-dimensional problem formulation. The findings have proven that, if the two-dimensional problem is considered, any excessive pore pressure is concentrated immediately under the area exposed to the localized loading, and it penetrates into the depth equal to 1/2 of the strength of the compressed width. Subfoundation subsidence is caused by both shear and 3D deformations of soil. Besides, the ratio of shear-to-3D deformations reaches 10. Therefore, the authors propose to represent the subfoundation subsidence as the sum of shear and 3D deformations.The differential equation of the filter consolidation, if considered as the 2D problem, is solved using the Mathcad software. The software is used to analyze the isolines of excessive pore pressure at any moment following the loading application. New depen- dence representing the ratio of the changing area of the diagram of the average effective tension to the area of the diagram of the average tension in the stabilized condition is proposed by the authors.In the final section of the article, the authors solve the problem of prognostication of the subsidence pattern for the water saturated subfoundation with account for the shear creep of the soil skeleton. The authors employ the visco-elastic Bingham model characterized by time-dependent viscosity ratios. The authors have proven that in this case the subsidence following the shear load will develop as of the moment of application of the external load pro rata the logarithm of time irrespectively of the process of filtration consolidation.????????? ?????????? ? ??????? ????? ???????????? ? ?????????? ?????????????? ????????? ?? ????????? ??????? ??? ???????????? ??????? ???????? (??????? ??????. ????????, ??? ? ???????? ??????? ?????? ?????????? ??????? ???????? ? ????????? ?????? ?????????? ???????????? ??????????????? ??? ??????? ????????? ?? ??????? 1/2 ?? ???????? ????????? ????? ? ????? ????????? ???? ?? ??????? ? ??? ?????? ????????? ??????????? ??? ??????????, ??? ? ????????? ???????????? ??????. ????? ????, ??????????? ????????? ? ???????? ?????? ????????? 10. ??????? ?????????? ?????? ????????? ?????????? ? ???? ????? ?? ???????? ? ????????? ?????????? ? ???????????.??? ??????? ????????????????? ????????? ?????????????? ???????????? ? ???????? ?????????? ?????? ???????????? ??????????? ???????? Mathcad. ??? ????????? ??????????? ??????? ?? ??????????? ???????? ??????????? ???????? ???????? ??? ?????? ??????? ??????? ?? ?????? ?????????? ????????. ??? ??????????? ??????? ???????????? ?????? ?????????? ????? ??????????? ? ???? ????????? ???????????? ??????? ????? ???????? ???????????? ?????????? ? ??????? ????? ???????? ?????????? ? ????????????????? ?????????.? ?????????????? ??????? ?????? ????????? ??????? ?????? ?? ??????????????? ?????? ??????????????? ????????? ? ?????? ?????????

  9. Pulse widths effects on scintillator saturation

    International Nuclear Information System (INIS)

    A test was performed over an extensive range of irrradiance (approximately five orders of magnitude) to see to what extent organic scintillators responded linearly with x-ray input. At the highest levels of irradiance achievable with the experimental configuration, but only for pulses in the region of 4.0 ns or wider, a degree of nonlinear response was observed for some of the scintillators. The data suggest that at levels below 1 mJ/cm2-ns it is safe to asume that for pulses 6.5 ns and shorter there is no significant level of nonlinearity to x rays with spectrum. For the cases of undoped NE111 and NE111 doped with 10 percent benzophenone, experimental conditions were such that it was possible to accumulate data significantly above the 1 mJ/cm2-ns level of irradiance. It is with these cases that a nonlinear response was observed. It is assumed that the same nonlinearity would have also been noticed had experimental conditions been such that equivalent levels of irradiance could have been achieved at the time the other samples were studied

  10. Research on Fairway Width Design in Curved Bridge Waters Channel

    OpenAIRE

    Chi Hong-Fu; Wang Yuan-Jiao

    2013-01-01

    Bridge construction can promote economic development but if the bridge layout is unreasonable, it would hinder ship’s safety navigation in the bridge area. There is little reference for fairway width design about curved bridge channel in ??inland river navigation standards?? of China. In this study, a fairway width design method in curved bridge channel was put forward by taking into account the scope of turbulent scope of pier, ship’s track width, drifting distance due to wind, d...

  11. The significance of biometric parameters in determining anterior teeth width

    Directory of Open Access Journals (Sweden)

    Strajni? Ljiljana

    2013-01-01

    Full Text Available Background/Aim. An important element of prosthetic treatment of edentulous patients is selecting the size of anterior artificial teeth that will restore the natural harmony of one’s dentolabial structure as well as the whole face. The main objective of this study was to determine the correlation between the inner canthal distance (ICD and interalar width (IAW on one side and the width of both central incisors (CIW, the width of central and lateral incisors (CLIW, the width of anterior teeth (ATW, the width between the canine cusps (CCW, which may be useful in clinical practice. Methods. A total of 89 subjects comprising 23 male and 66 female were studied. Their age ranged from 19 to 34 years with the mean of 25 years. Only the subjects with the preserved natural dentition were included in the sample. All facial and intraoral tooth measurements were made with a Boley Gauge (Buffalo Dental Manufacturing Co., Brooklyn NY, USA having a resolution of 0.1mm. Results. A moderate correlation was established between the interalar width and combined width of anterior teeth and canine cusp width (r = 0.439, r = 0.374. A low correlation was established between the inner canthal distance and the width of anterior teeth and canine cusp width (r = 0.335, r = 0.303. The differences between the two genders were highly significant for all the parameters (p < 0.01. The measured facial distances and width of anterior teeth were higher in men than in women. Conclusion. The results of this study suggest that the examined interalar width and inner canthal distance cannot be considered reliable guidelines in the selection of artificial upper anterior teeth. However, they may be used as a useful additional factor combined with other methods for objective tooth selection. The final decision should be made while working on dentures fitting models with the patient’s consent.

  12. The Local Lyman-$\\alpha$ Forest; 1, Distribution of HI Absorbers, Doppler Widths, and Baryon Content

    CERN Document Server

    Penton, S V; Stocke, J T; Penton, Steven V.; Stocke, John T.

    1999-01-01

    In Paper I of this series (astro-ph/9911117) we described observations of 15 extragalactic targets taken with the Hubble Space Telescope GHRS/G160M grating for studies of the low-z Lya forest. We reported the detection of 110 Lya absorbers at significance level >3 sigma in the redshift range z=0.002-0.069, over a total pathlength of 116,000 km/s. In this second paper, we evaluate the physical properties of these Lya absorbers and compare them to their high-z counterparts. The distribution of Doppler parameters is similar to that at high redshift, with mean b = 35.0 +- 16.6 km/s. The true Doppler parameter may be somewhat lower, owing to component blends and non-thermal velocities. The distribution of equivalent widths exhibits a significant break at W~133mA, with an increasing number of weak absorbers (10mA-100mA). Adopting a curve of growth with b = 25 +- 5km/s and applying a sensitivity correction as a function of equivalent width and wavelength, we derive the distribution in column density, Nh^{-1.80+-0.05...

  13. Speed analyses of stimulus equivalence.

    OpenAIRE

    Spencer, T. J.; Chase, P. N.

    1996-01-01

    The functional substitutability of stimuli in equivalence classes was examined through analyses of the speed of college students' accurate responding. After training subjects to respond to 18 conditional relations, subjects' accuracy and speed of accurate responding were compared across trial types (baseline, symmetry, transitivity, and combined transitivity and symmetry) and nodal distance (one- through five-node transitive and combined transitive and symmetric relations). Differences in acc...

  14. Light WIMPs And Equivalent Neutrinos

    OpenAIRE

    STEIGMAN, GARY; Nollett, Kenneth M.

    2014-01-01

    Very light WIMPs (chi), thermal relics that annihilate late in the early Universe, change the energy and entropy densities at BBN and at recombination. BBN, in combination with the CMB, can remove some of the degeneracies among light WIMPs and equivalent neutrinos, constraining the existence and properties of each. Depending on the nature of the light WIMP (Majorana or Dirac fermion, real or complex scalar) the joint BBN + CMB analyses set lower bounds to m_chi in the range ...

  15. Asymptotic estimation of widths of the quasistationary states

    International Nuclear Information System (INIS)

    The new integral formalism for the calculation of the width of the quasistationary states without using smallness of the barrier penetration factor is proposed. Asymptotic formula for the width of the short-living quasistationary states on the base of saddle-point approximation is derived. On the base of our approach the widths of ?-decay of the Pb isotopes, baryon resonances and dibaryon resonances were calculated. A good agreement of the theory and experiment was demonstrated. The natural explanation of the small widths of low lying dibaryon resonances was argued. (author). 23 refs., 1 fig., 4 tabs

  16. VizieR Online Data Catalog: CaII triplet equivalent widths in 30 globulars (Mauro+, 2014)

    Science.gov (United States)

    Mauro, F.; Moni Bidin, C.; Geisler, D.; Saviane, I.; da Costa, G. S.; Gormaz-Matamala, A. C.; Vasquez, S.; Chene, A.-N.; Cohen, R.; Dias, B.

    2014-03-01

    Our main target list consists of the GCs analyzed by S12 (Saviane et al., 2012, Cat. J/A+A/540/A27). The NIR imaging collected in the context of the VVV Survey was used for all clusters included in the survey area. We also checked whether any of the GCs in the dataset not observed by the VVV Survey had useful 2MASS photometry, that would permit us to determine the RHB position. We similarly selected GCs from the R97 (Rutledge et al., 1997PASP..109..907R) catalog to determine a calibration for this dataset as well (2 data files).

  17. Ly{\\alpha} Equivalent Width Distribution of Ly{\\alpha} Emitting Galaxies at Redshift z $\\sim$ 4.5

    OpenAIRE

    Zheng, Zhen-Ya; Wang, Jun-Xian; Malhotra, Sangeeta; Rhoads, James E; Finkelstein, Steven L.; Finkelstein, Keely

    2013-01-01

    Ly{\\alpha} line EWs provide important clues to the physical nature of high redshift LAEs. However, measuring the Ly{\\alpha} EW distribution of high-z narrowband selected LAEs can be hard because many sources do not have broadband photometry. We investigate the possible biases in measuring the intrinsic Ly{\\alpha} EW distribution for a LAE sample at z $\\sim$ 4.5 in the Extended CDFS. Only weak Malmquist-type bias in both the intrinsic Ly{\\alpha} luminosity function and the Ly...

  18. High-Resolution Near-Infrared Spectroscopy of an Equivalent Width-Selected Sample of Starbursting Dwarf Galaxies

    Science.gov (United States)

    Maseda, Michael V.; VanDerWeL, Arjen; DaChuna, Elisabete; Rix, Hans-Walter; Pacafichi, Camilla; Momcheva, Ivelina; Brammer, Gabriel B.; Franx, Marijn; VanDokkum, Pieter; Bell, Eric F.; Ferguson, Harry C.; Fumagalli, Mattia; Grogin, Norman A.; Kocevski, Dale D.; Koekemoer, Anton M.; Lundgren, Britt F.; Marchesini, Danilo; Nelson, Erica J.; Patel, Shannon; Skelton, Rosalind E.; Straughn, Amber N.; Trump, Jonathan R.; Weiner, Benjamin J.; Whitaker, Katherine E.; Wuyts, Stijn

    2013-01-01

    Spectroscopic observations from the Large Binocular Telescope and the Very Large Telescope reveal kinematically narrow lines (approx. 50 km/s) for a sample of 14 Extreme Emission Line Galaxies (EELGs) at redshifts 1.4 formed in this vigorous starburst phase thus represents a large fraction of the total (dynamical) mass, without a significantly massive underlying population of older stars. The occurrence of such intense events in shallow potentials strongly suggests that supernova-driven winds must be of critical importance in the subsequent evolution of these systems.

  19. Numerical study on effect of gap width of narrow rectangular channel on critical heat flux enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Huang Jun [State Key Laboratory of Multiphase Flow in Power Engineering, Xi' an Jiaotong University, Xi' an 710049 (China); National Key Laboratory of Bubble Physics and Natural Circulation, Nuclear Power Institute of China, Chengdu 610041 (China); Huang Yanping [National Key Laboratory of Bubble Physics and Natural Circulation, Nuclear Power Institute of China, Chengdu 610041 (China); Wang Qiuwang [State Key Laboratory of Multiphase Flow in Power Engineering, Xi' an Jiaotong University, Xi' an 710049 (China)], E-mail: wangqw@mail.xjtu.edu.cn; Bai Bofeng [State Key Laboratory of Multiphase Flow in Power Engineering, Xi' an Jiaotong University, Xi' an 710049 (China)

    2009-02-15

    According to the flow passage characteristic of narrow rectangular channel and liquid film dry-out mechanics of annular flow critical heat flux (CHF), an annular flow CHF analytical model for narrow rectangular channel has been achieved. This model may be used to predict the CHF behavior of boiling two-phase flow in narrow rectangular channel with gap width of not being less than 0.0005 m (the equivalent diameter of this channel is 0.001 m). Through analyzing and calculating, when the inlet dimensionless gap width of narrow rectangular channel is within 30-85, the enhancement of CHF in channel is obvious. At the same time, according to the characteristic of two-phase flow, the new determinant laws of CHF in boiling two-phase flow system have been derived. Through analyzing and calculating, it is substantial that this determinant laws is appropriate. The best dimensionless gap width of heat flux enhancement has been achieved to be 45-75.

  20. Neutron-induced background by an alpha-beam incident on a deuterium gas target and its implications for the study of the 2H(alpha,gamma)6Li reaction at LUNA

    CERN Document Server

    Anders, M; Bellini, A; Aliotta, M; Bemmerer, D; Broggini, C; Caciolli, A; Costantini, H; Corvisiero, P; Davinson, T; Elekes, Z; Erhard, M; Formicola, A; Fülöp, Zs; Gervino, G; Guglielmetti, A; Gustavino, C; Gyürky, Gy; Junker, M; Lemut, A; Marta, M; Mazzocchi, C; Menegazzo, R; Prati, P; Alvarez, C Rossi; Scott, D; Somorjai, E; Straniero, O; Szücs, T

    2013-01-01

    The production of the stable isotope Li-6 in standard Big Bang nucleosynthesis has recently attracted much interest. Recent observations in metal-poor stars suggest that a cosmological Li-6 plateau may exist. If true, this plateau would come in addition to the well-known Spite plateau of Li-7 abundances and would point to a predominantly primordial origin of Li-6, contrary to the results of standard Big Bang nucleosynthesis calculations. Therefore, the nuclear physics underlying Big Bang Li-6 production must be revisited. The main production channel for Li-6 in the Big Bang is the 2H(alpha,gamma)6Li reaction. The present work reports on neutron-induced effects in a high-purity germanium detector that were encountered in a new study of this reaction. In the experiment, an {\\alpha}-beam from the underground accelerator LUNA in Gran Sasso, Italy, and a windowless deuterium gas target are used. A low neutron flux is induced by energetic deuterons from elastic scattering and, subsequently, the 2H(d,n)3He reaction....

  1. Video digitizer (real time-frame grabber) with region of interest suitable for quantitative data analysis used on the infrared and H alpha cameras installed on the DIII-D experiment

    International Nuclear Information System (INIS)

    This paper describes a CAMAC based video digitizer with region of interest (ROI) capability that was designed for use with the infrared and H alpha cameras installed by Lawrence Livermore Laboratory on the DIII-D experiment at G.A. Technologies in San Diego, California. The video digitizer uses a custom built CAMAC video synchronizer module to clock data into a CAMAC transient recorder on a line-by-line basis starting at the beginning of a field. The number of fields that are recorded is limited only by the available transient recorder memory. In order to conserve memory, the CAMAC video synchronizer module provides for the alternative selection of a specific region of interest in each successive field to be recorded. Memory conservation can be optimized by specifying lines in the field, start time, stop time, and the number of data samples per line. This video frame grabber has proved versatile for capturing video in such diverse applications as recording video fields from a video tape recorder played in slow motion or recording video fields in real time during a DIII-D shot. In other cases, one or more lines of video are recorded per frame to give a cross sectional slice of the plasma. Since all the data in the digitizer memory is synchronized to video fields and lines, the data can be read directly into the control computer in the proper matrix format to facilitate rapid processing, display, and permanent storage

  2. GLACE survey: OSIRIS/GTC Tuneable Filter H$\\alpha$ imaging of the rich galaxy cluster ZwCl 0024.0+1652 at z = 0.395. Part I -- Survey presentation, TF data reduction techniques and catalogue

    CERN Document Server

    Sánchez-Portal, Miguel; Pérez-Martínez, Ricardo; Cepa, Jordi; García, Ana M Pérez; Domínguez-Sánchez, Helena; Bongiovanni, Ángel; Serra, Ana L; Alfaro, Emilio; Altieri, Bruno; Aragón-Salamanca, Alfonso; Balkowski, Chantal; Biviano, Andrea; Bremer, Malcom; Castander, Francisco; Castañeda, Héctor; Castro-Rodríguez, Nieves; Chies-Santos, Ana L; Coia, Daniela; Diaferio, Antonaldo; Duc, Pierre-Alain; Ederoclite, Alessandro; Geach, James; González-Serrano, Ignacio; Haines, Chris P; McBreen, Brian; Metcalfe, Leo; Oteo, Iván; Pérez-Fournón, Ismael; Poggianti, Bianca; Polednikova, Jana; Ramón-Pérez, Marina; Rodríguez-Espinosa, José M; Santos, Joana S; Smail, Ian; Smith, Graham P; Temporin, Sonia; Valtchanov, Ivan

    2015-01-01

    The cores of clusters at 0 $\\lesssim$ z $\\lesssim$ 1 are dominated by quiescent early-type galaxies, whereas the field is dominated by star-forming late-type ones. Galaxy properties, notably the star formation (SF) ability, are altered as they fall into overdense regions. The critical issues to understand this evolution are how the truncation of SF is connected to the morphological transformation and the responsible physical mechanism. The GaLAxy Cluster Evolution Survey (GLACE) is conducting a study on the variation of galaxy properties (SF, AGN, morphology) as a function of environment in a representative sample of clusters. A deep survey of emission line galaxies (ELG) is being performed, mapping a set of optical lines ([OII], [OIII], H$\\beta$ and H$\\alpha$/[NII]) in several clusters at z $\\sim$ 0.40, 0.63 and 0.86. Using the Tunable Filters (TF) of OSIRIS/GTC, GLACE applies the technique of TF tomography: for each line, a set of images at different wavelengths are taken through the TF, to cover a rest fra...

  3. Equivalent velocity spectroscopy for development of femtosecond pulse radiolysis system

    International Nuclear Information System (INIS)

    For studies of electron beam induced ultra-fast reaction process, femtosecond (fs) pulse radiolysis is under construction. To realize fs time resolution, fs electron and analyzing light pulses and their jitter compensation system are needed. About a 100fs electron pulse was generated by a photocathode RF gun LINAC and a magnetic pulse compressor. Synchronized Ti: Sapphire laser have a pulse width about 160fs. And, it is significant to avoid degradation of time resolution caused by velocity difference between electron and analyzing light in a sample. In the 'Equivalent velocity spectroscopy' method, incident analyzing light is slant toward electron beam with an angle associated with refractive index of sample. Then, to overlap light wave front and electron pulse shape, electron pulse shape is slanted toward the direction of travel. As a result of the equivalent velocity spectroscopy for hydrated electrons, using slanted electron pulse shape, optical absorption rise time was about 1.4ps faster than normal electron pulse shape. Thus, the 'Equivalent velocity spectroscopy' is effective for femtosecond pulse radiolysis. (author)

  4. Measuring Slit Width and Separation in a Diffraction Experiment

    Science.gov (United States)

    Gan, K. K.; Law, A. T.

    2009-01-01

    We present a procedure for measuring slit width and separation in single- and double-slit diffraction experiments. Intensity spectra of diffracted laser light are measured with an optical sensor (PIN diode). Slit widths and separations are extracted by fitting to the measured spectra. We present a simple fitting procedure to account for the…

  5. Experimental limits on the width of the reported ?(1540)+

    International Nuclear Information System (INIS)

    Using data on K+ collisions on xenon and deuterium we derive values and limits on the width of the reported ?(1540)+ exotic baryon resonance. The xenon experiment gives a width of 0.9±0.3 MeV. The other experiments give upper limits in the range 1-4 MeV

  6. Equivalence of dose response curves

    OpenAIRE

    Dette, Holger; Möllenhoff, Kathrin; Volgushev, Stanislav; Bretz, Frank

    2015-01-01

    This paper investigates the problem if the difference between two parametric models $m_1, m_2$ describing the relation between the response and covariates in two groups is of no practical significance, such that inference can be performed on the basis of the pooled sample. Statistical methodology is developed to test the hypotheses $H_0: d(m_1,m_2) \\geq \\varepsilon$ versus $H_1: d(m_1,m_2) < \\varepsilon$ of equivalence between the two regression curves $m_1, m_2$, where $d$ ...

  7. Equivalent generalized perturbation theory (EGPT)

    International Nuclear Information System (INIS)

    Based on the well-established generalized perturbation theory (GPT), an equivalent method (EGPT) is proposed. An advantage of this new formulation is that in many circumstances of interest the difficulties in calculating the functions entering into the perturbation expressions can be simplified, in particular, allowing us to reduce the equations governing them from an inhomogeneous to a homogeneous form. After a general derivation of the method, its specialization to a number of different problems is made. Numerical tests for a variety of cases are finally illustrated, confirming the validity of the EGPT methodology. (author)

  8. Configuration of equivalent f electrons

    International Nuclear Information System (INIS)

    The term 2F given to the ions Ce3+ and Yb3+ is due to an electron or to one hole, respectively, in the 4f configuration of the lanthanide elements. When the number of equivalent electrons (or holes) becomes larger than one, there is an increase in the number of terms. Considerations about the classification of terms to differentiate states of a given f sup(n) configuration are made on the basis of group theory. It is shown that different sets of quantum numbers are necessary to distinguish levels with the same representations and with different energies. (C.L.B.)

  9. Research on Fairway Width Design in Curved Bridge Waters Channel

    Directory of Open Access Journals (Sweden)

    Chi Hong-Fu

    2013-01-01

    Full Text Available Bridge construction can promote economic development but if the bridge layout is unreasonable, it would hinder ship’s safety navigation in the bridge area. There is little reference for fairway width design about curved bridge channel in ??inland river navigation standards?? of China. In this study, a fairway width design method in curved bridge channel was put forward by taking into account the scope of turbulent scope of pier, ship’s track width, drifting distance due to wind, drifting distance due to current, the scope of ship’s safety field and additional width in curved channel. The fairway width design concept for curved bridge channel presented in this studyit may provide reference for bridge design and other fairway layout.

  10. 77 FR 55832 - Ambient Air Monitoring Reference and Equivalent Methods: Designation of a New Equivalent Method

    Science.gov (United States)

    2012-09-11

    ...Ambient Air Monitoring Reference and Equivalent Methods: Designation of a New Equivalent Method AGENCY: Environmental Protection Agency. ACTION...Notice of the designation of a new equivalent method for monitoring ambient air...

  11. Investigation of Equivalent Circuit for PEMFC Assessment

    International Nuclear Information System (INIS)

    Chemical reactions occurring in a PEMFC are dominated by the physical conditions and interface properties, and the reactions are expressed in terms of impedance. The performance of a PEMFC can be simply diagnosed by examining the impedance because impedance characteristics can be expressed by an equivalent electrical circuit. In this study, the characteristics of a PEMFC are assessed using the AC impedance and various equivalent circuits such as a simple equivalent circuit, equivalent circuit with a CPE, equivalent circuit with two RCs, and equivalent circuit with two CPEs. It was found in this study that the characteristics of a PEMFC could be assessed using impedance and an equivalent circuit, and the accuracy was highest for an equivalent circuit with two CPEs

  12. 7 CFR 1000.54 - Equivalent price.

    Science.gov (United States)

    2010-01-01

    ...PROVISIONS OF FEDERAL MILK MARKETING ORDERS Class Prices § 1000.54 Equivalent...administrator shall use a price or pricing constituent...Programs, Agricultural Marketing Service, to be equivalent to the price or pricing...

  13. From body burden to effective dose equivalent

    International Nuclear Information System (INIS)

    The necessary data to calculate the effective committed dose equivalent and the effective dose-equivalent rate from measured body burdens are presented. Both ingestion and inhalation intakes are considered, for single intake as well as for continuous exposure

  14. Light WIMPs And Equivalent Neutrinos

    CERN Document Server

    Steigman, Gary

    2014-01-01

    Very light WIMPs (chi), thermal relics that annihilate late in the early Universe, change the energy and entropy densities at BBN and at recombination. BBN, in combination with the CMB, can remove some of the degeneracies among light WIMPs and equivalent neutrinos, constraining the existence and properties of each. Depending on the nature of the light WIMP (Majorana or Dirac fermion, real or complex scalar) the joint BBN + CMB analyses set lower bounds to m_chi in the range 0.5 - 5 MeV (m_chi/m_e > 1 - 10), and they identify best fit values for m_chi in the range 5 - 10 MeV. The joint BBN + CMB analysis finds a best fit value for the number of equivalent neutrinos, Delta N_nu ~ 0.65, nearly independent of the nature of the WIMP. In the absence of a light WIMP (m_chi > 20 MeV), N_eff = 3.05(1 + Delta N_nu /3). In this case, there is excellent agreement between BBN and the CMB, but the joint fit reveals Delta N_nu = 0.40+-0.17, disfavoring standard big bang nucleosynthesis (SBBN) (Delta N_nu = 0) at ~ 2.4 sigma...

  15. A Discrete Equivalent of the Logistic Equation

    OpenAIRE

    Petropoulou EugeniaN

    2010-01-01

    A discrete equivalent and not analogue of the well-known logistic differential equation is proposed. This discrete equivalent logistic equation is of the Volterra convolution type, is obtained by use of a functional-analytic method, and is explicitly solved using the -transform method. The connection of the solution of the discrete equivalent logistic equation with the solution of the logistic differential equation is discussed. Also, some differences of the discrete equivalent logistic equa...

  16. Auto-equivalences of stable module categories

    OpenAIRE

    Dugas, Alex

    2014-01-01

    We construct nontrivial auto-equivalences of stable module categories for elementary, local symmetric algebras over a field k. These auto-equivalences are modeled after the spherical twists of Seidel and Thomas and the $\\mathbb{P}^n$-twists of Huybrechts and Thomas, which yield auto-equivalences of the derived category of coherent sheaves on a variety. For group algebras of p-groups in characteristic p we recover many of the auto-equivalences corresponding to endo-trivial mo...

  17. Once Again on the Equivalence Theorem

    Science.gov (United States)

    Tyutin, I. V.

    2002-01-01

    We present the proof of the equivalence theorem in quantum field theory which is based on a formulation of this problem in the field-antifield formalism. As an example, we consider a model in which a different choices of natural finite counterterms is possible, leading to physically non-equivalent quantum theories while the equivalent theorem remains valid.

  18. Once again on the equivalence theorem

    OpenAIRE

    Tyutin, I. V.

    2000-01-01

    We present the proof of the equivalence theorem in quantum field theory which is based on a formulation of this problem in the field-antifield formalism. As an example, we consider a model in which a different choices of natural finite counterterms is possible, leading to physically non-equivalent quantum theories while the equivalent theorem remains valid.

  19. Once again on the equivalence theorem

    CERN Document Server

    Tyutin, I V

    2002-01-01

    We present the proof of the equivalence theorem in quantum field theory which is based on a formulation of this problem in the field-anitfield formalism. As an example, we consider a model in which a different choices of natural finite counterterms is possible, leading to physically non-equivalent quantum theories while the equivalent theorem remains valid.

  20. The definition of the individual dose equivalent

    International Nuclear Information System (INIS)

    A brief note examines the choice of the present definition of the individual dose equivalent, the new operational dosimetry quantity for external exposure. The consequences of the use of the individual dose equivalent and the danger facing the individual dose equivalent, as currently defined, are briefly discussed. (UK)

  1. The accessibility rank of weak equivalences

    OpenAIRE

    Raptis, G.; Rosicky?, J.

    2014-01-01

    We study the accessibility properties of trivial cofibrations and weak equivalences in a combinatorial model category and give an estimate for the accessibility rank of weak equivalences in certain Cisinski model categories. In particular, we show that the class of weak equivalences between simplicial sets is finitely accessible.

  2. Some spectral equivalences between Schroedinger operators

    International Nuclear Information System (INIS)

    Spectral equivalences of the quasi-exactly solvable sectors of two classes of Schroedinger operators are established, using Gaudin-type Bethe ansatz equations. In some instances the results can be extended leading to full isospectrality. In this manner we obtain equivalences between PT-symmetric problems and Hermitian problems. We also find equivalences between some classes of Hermitian operators

  3. Some spectral equivalences between Schrodinger operators

    CERN Document Server

    Dunning, C; Links, J

    2008-01-01

    Spectral equivalences of the quasi-exactly solvable sectors of two classes of Schrodinger operators are established, using Gaudin-type Bethe ansatz equations. In some instances the results can be extended leading to full isospectrality. In this manner we obtain equivalences between PT-symmetric problems and Hermitian problems. We also find equivalences between some classes of Hermitian operators.

  4. On graph classes with logarithmic boolean-width

    CERN Document Server

    Belmonte, Rémy

    2010-01-01

    Boolean-width is a recently introduced graph parameter. Many problems are fixed parameter tractable when parametrized by boolean-width, for instance "Minimum Weighted Dominating Set" (MWDS) problem can be solved in $O^*(2^{3k})$ time given a boolean-decomposition of width $k$, hence for all graph classes where a boolean-decomposition of width $O(\\log n)$ can be found in polynomial time, MWDS can be solved in polynomial time. We study graph classes having boolean-width $O(\\log n)$ and problems solvable in $O^*(2^{O(k)})$, combining these two results to design polynomial algorithms. We show that for trapezoid graphs, circular permutation graphs, convex graphs, Dilworth-$k$ graphs, circular arc graphs and complements of $k$-degenerate graphs, boolean-decompositions of width $O(\\log n)$ can be found in polynomial time. We also show that circular $k$-trapezoid graphs have boolean-width $O(\\log n)$, and find such a decomposition if a circular $k$-trapezoid intersection model is given. For many of the graph classes ...

  5. Neutron-induced background by an {alpha}-beam incident on a deuterium gas target and its implications for the study of the {sup 2}H({alpha},{gamma}){sup 6}Li reaction at LUNA

    Energy Technology Data Exchange (ETDEWEB)

    Anders, M.; Bemmerer, D.; Elekes, Z.; Marta, M. [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany); Trezzi, D.; Mazzocchi, C. [INFN, Sezione di Milano, Milano (Italy); Bellini, A.; Costantini, H.; Corvisiero, P.; Lemut, A.; Prati, P. [Universita di Genova (Italy); INFN, Sezione di Genova, Dipartimento di Fisica, Genova (Italy); Aliotta, M.; Davinson, T.; Scott, D. [University of Edinburgh, SUPA, School of Physics and Astronomy, Edinburgh (United Kingdom); Broggini, C.; Caciolli, A.; Erhard, M.; Menegazzo, R.; Rossi Alvarez, C. [INFN, Sezione di Padova, Padova (Italy); Formicola, A.; Junker, M. [Laboratori Nazionali del Gran Sasso, INFN, Assergi (Italy); Fueloep, Zs.; Gyuerky, G.; Somorjai, E.; Szuecs, T. [Institute of Nuclear Research (ATOMKI), Debrecen (Hungary); Gervino, G. [Universita di Torino (Italy); INFN, Dipartimento di Fisica Sperimentale, Torino (Italy); Guglielmetti, A. [INFN, Sezione di Milano, Milano (Italy); Universita degli Studi di Milano, Milano (Italy); Gustavino, C. [INFN, Sezione di Roma ' ' La Sapienza' ' , Roma (Italy); Straniero, O. [INFN, Sezione di Napoli, Napoli (Italy); Osservatorio Astronomico di Collurania, Teramo (Italy); Collaboration: LUNA Collaboration

    2013-02-15

    The production of the stable isotope {sup 6}Li in standard Big Bang nucleosynthesis has recently attracted much interest. Recent observations in metal-poor stars suggest that a cosmological {sup 6}Li plateau may exist. If true, this plateau would come in addition to the well-known Spite plateau of {sup 7}Li abundances and would point to a predominantly primordial origin of {sup 6}Li, contrary to the results of standard Big Bang nucleosynthesis calculations. Therefore, the nuclear physics underlying Big Bang {sup 6}Li production must be revisited. The main production channel for {sup 6}Li in the Big Bang is the {sup 2}H({alpha},{gamma}){sup 6}Li reaction. The present work reports on neutron-induced effects in a high-purity germanium detector that were encountered in a new study of this reaction. In the experiment, an {alpha}-beam from the underground accelerator LUNA in Gran Sasso, Italy, and a windowless deuterium gas target are used. A low neutron flux is induced by energetic deuterons from elastic scattering and, subsequently, the {sup 2}H(d,n){sup 3}He reaction. Due to the ultra-low laboratory neutron background at LUNA, the effect of this weak flux of 2-3 MeV neutrons on well-shielded high-purity germanium detectors has been studied in detail. Data have been taken at 280 and 400keV {alpha}-beam energy and for comparison also using an americium-beryllium neutron source. (orig.)

  6. Nightside studies of coherent HF Radar spectral width behaviour

    Directory of Open Access Journals (Sweden)

    E. E. Woodfield

    Full Text Available A previous case study found a relationship between high spectral width measured by the CUTLASS Finland HF radar and elevated electron temperatures observed by the EISCAT and ESR incoherent scatter radars in the post-midnight sector of magnetic local time. This paper expands that work by briefly re-examining that interval and looking in depth at two further case studies. In all three cases a region of high HF spectral width (>200 ms-1 exists poleward of a region of low HF spectral width (<200 ms-1. Each case, however, occurs under quite different geomagnetic conditions. The original case study occurred during an interval with no observed electrojet activity, the second study during a transition from quiet to active conditions with a clear band of ion frictional heating indicating the location of the flow reversal boundary, and the third during an isolated sub-storm. These case studies indicate that the relationship between elevated electron temperature and high HF radar spectral width appears on closed field lines after 03:00 magnetic local time (MLT on the nightside. It is not clear whether the same relationship would hold on open field lines, since our analysis of this relationship is restricted in latitude. We find two important properties of high spectral width data on the nightside. Firstly the high spectral width values occur on both open and closed field lines, and secondly that the power spectra which exhibit high widths are both single-peak and multiple-peak. In general the regions of high spectral width (>200 ms-1 have more multiple-peak spectra than the regions of low spectral widths whilst still maintaining a majority of single-peak spectra. We also find that the region of ion frictional heating is collocated with many multiple-peak HF spectra. Several mechanisms for the generation of high spectral width have been proposed which would produce multiple-peak spectra, these are discussed in relation to the data presented here. Since the regions of high spectral width are observed both on closed and open field lines the use of the boundary between low and high spectral width as an ionospheric proxy for the open/closed field line boundary is not a simple matter, if indeed it is possible at all.

    Key words. Ionosphere (auroral ionosphere; ionospheric irregularities

  7. Equivalent Hamiltonian for Lee Model

    CERN Document Server

    Jones, H F

    2007-01-01

    Using the techniques of quasi-Hermitian quantum mechanics and quantum field theory we use a similarity transformation to construct an equivalent Hermitian Hamiltonian for the Lee model. In the field theory confined to the $V/N\\theta$ sector it effectively decouples $V$, replacing the three-point interaction of the original Lee model by an additional mass term for the $V$ particle and a four-point interaction between $N$ and $\\theta$. While the construction is originally motivated by the regime where the bare coupling becomes imaginary, leading to a ghost, it applies equally to the standard Hermitian regime where the bare coupling is real. In that case the similarity transformation becomes a unitary transformation.

  8. Symmetries of dynamically equivalent theories

    CERN Document Server

    Gitman, D M

    2005-01-01

    A natural and very important development of constrained system theory is a detail study of the relation between the constraint structure in the Hamiltonian formulation with specific features of the theory in the Lagrangian formulation, especially the relation between the constraint structure with the symmetries of the Lagrangian action. An important preliminary step in this direction is a strict demonstration, and this is the aim of the present article, that the symmetry structures of the Hamiltonian action and of the Lagrangian action are the same. This proved, it is sufficient to consider the symmetry structure of the Hamiltonian action. The latter problem is, in some sense, simpler because the Hamiltonian action is a first-order action. At the same time, the study of the symmetry of the Hamiltonian action naturally involves Hamiltonian constraints as basic objects. One can see that the Lagrangian and Hamiltonian actions are dynamically equivalent. This is why, in the present article, we consider from the v...

  9. Einstein's equivalence principle in cosmology

    CERN Document Server

    Kopeikin, Sergei M

    2013-01-01

    We study physical consequences of the Einstein equivalence principle (EEP) for a Hubble observer in FLRW universe. We introduce the local inertial coordinates with the help of a special conformal transformation. The local inertial metric is Minkowski flat and materialized by a congruence of time-like geodesics of static observers. The static observers are equipped with the ideal clocks measuring the proper time that is synchronized with the clocks of the Hubble observer. The local inertial metric is used for physical measurements of spacetime intervals with the ideal clocks and rulers. The special conformal transformation preserves null geodesics but does not keep invariant time-like geodesics. Moreover, it makes the rate of the local time coordinate dependent on velocity of the particle which makes impossible to rich the uniform parameterization of the world lines of static observers and light geodesics with a single parameter - they differ by the conformal factor of FLRW metric. The most convenient way to s...

  10. Expanding the Interaction Equivalency Theorem

    Directory of Open Access Journals (Sweden)

    Brenda Cecilia Padilla Rodriguez

    2015-06-01

    Full Text Available Although interaction is recognised as a key element for learning, its incorporation in online courses can be challenging. The interaction equivalency theorem provides guidelines: Meaningful learning can be supported as long as one of three types of interactions (learner-content, learner-teacher and learner-learner is present at a high level. This study sought to apply this theorem to the corporate sector, and to expand it to include other indicators of course effectiveness: satisfaction, knowledge transfer, business results and return on expectations. A large Mexican organisation participated in this research, with 146 learners, 30 teachers and 3 academic assistants. Three versions of an online course were designed, each emphasising a different type of interaction. Data were collected through surveys, exams, observations, activity logs, think aloud protocols and sales records. All course versions yielded high levels of effectiveness, in terms of satisfaction, learning and return on expectations. Yet, course design did not dictate the types of interactions in which students engaged within the courses. Findings suggest that the interaction equivalency theorem can be reformulated as follows: In corporate settings, an online course can be effective in terms of satisfaction, learning, knowledge transfer, business results and return on expectations, as long as (a at least one of three types of interaction (learner-content, learner-teacher or learner-learner features prominently in the design of the course, and (b course delivery is consistent with the chosen type of interaction. Focusing on only one type of interaction carries a high risk of confusion, disengagement or missed learning opportunities, which can be managed by incorporating other forms of interactions.

  11. Equivalent Simplification Method of Micro-Grid

    Directory of Open Access Journals (Sweden)

    Cai Changchun

    2013-09-01

    Full Text Available The paper concentrates on the equivalent simplification method for the micro-grid system connection into distributed network. The equivalent simplification method proposed for interaction study between micro-grid and distributed network. Micro-grid network, composite load, gas turbine synchronous generation, wind generation are equivalent simplification and parallel connect into the point of common coupling. A micro-grid system is built and three phase and single phase grounded faults are performed for the test of the equivalent model of micro-grid. The simulation results show that the equivalent model of micro-grid is effective, and the dynamic of equivalent model is similar with the detailed model of micro-grid. The equivalent simplification method for the micro-grid network and distributed components is suitable for the study of micro-grid.  

  12. The width of the Z boson in composite models

    International Nuclear Information System (INIS)

    It is shown that in simple composite models in which the Z is bound by hypercolour forces with a compositeness scale of the same order as its mass, then the decay width will almost certainly exceed current experimental limits. (author)

  13. Leptonic widths of high excitations in heavy quarkonia

    International Nuclear Information System (INIS)

    Agreement with the measured electronic widths of the resonances ?(4040), ?(4415) and ?(11 019) is shown to be obtained if two effects are taken into account: (i) a flattening of the confining potential at distances r ?> 1.2 fm, which gives a drop in the leptonic widths of high excitations of about 10-20%, but does not affect low-lying states, and (ii) switching off the gluon-exchange (GE) interaction for those nS states which have a rms radius rn ?> 1.4 fm. We also show that an exponential type of screening of the GE interaction barely changes the leptonic widths, ?(nS), for n ? 5. The leptonic widths of ?e+e-(?(7S))=0.11 keV and ?(?(5S)) ? 0.54 keV are predicted

  14. The effect of buffer zone width on biodiversity

    DEFF Research Database (Denmark)

    Navntoft, SØren; Sigsgaard, Lene

    2012-01-01

    Field margin management for conservation purposes is a way to protect both functional biodiversity and biodiversity per se without considerable economical loss as field margins are less productive. However, the effect of width of the buffer zone on achievable biodiversity gains has received little attention in previous studies. In this paper we report on finding for syrphids, spiders and carabids, three taxonomic groups with different mobility, all important for conservation biological control. For all groups we found an effect of buffer zone width on their density. A buffer width of 6m was the narrowest that consistently promoted a higher abundance or activity of arthropods within the field area (outside the hedge bottom). However, a further increase in buffer width always increased the abundance and activity of arthropods a little more.

  15. Evaluation of spectral line width of atoms in liquid helium

    International Nuclear Information System (INIS)

    Laser induced fluorescence experiments indicate change of spectral line profiles of atoms and molecules compared to the free system when embedded under liquid helium. Based on relativistic density functional approach a model has been proposed here to estimate the width of the spectral lines embedded under liquid helium in which the central atom resides within a cluster of helium atoms. The model assumes an overall floppy motion of the liquid helium atoms due to finite temperature and subsequent determination of the width from the ab initio estimated potential energy diagram. Calculated width of the resonance lines of Rb and Cs show good agreement with available laser spectroscopic data. -- Highlights: ? We study the change of the resonant transitions of Alkali atoms in liquid Helium. ? Our model allows fully relativistic ab initio calculations of the line width of such a transition. ? Comparison with experiment for Rb and Cs is nearly complete.

  16. Influence of chemical binding on the neutron width ?n

    International Nuclear Information System (INIS)

    Highlights: ? In this paper, we calculate the mean value of the resolvent of the Schrodinger equation to derive a formal expression of the neutron width ?n which shows that the neutron width depends on the initial and intermediate states of the lattice after formation of the compound nucleus. ? An application is made to harmonic oscillator targets. - Abstract: In the studies of the broadening of neutron resonance reactions, it has always been assumed that one can neglect the dependence of the neutron width ?n on the initial and intermediate state of the lattice when the capturing atom is bound in a crystal. In this paper, we calculate the mean value of the resolvent of the Schrodinger equation to derive a formal expression of ?n that shows that the neutron width depends on the initial and intermediate state of the lattice after formation of the compound nucleus. An application is made to harmonic oscillators targets.

  17. Unprecedented grain size effect on stacking fault width

    Directory of Open Access Journals (Sweden)

    A. Hunter

    2013-09-01

    Full Text Available Using an atomistic-phase field dislocation dynamics model, we isolate and investigate grain size and stress effects on the stacking fault width created by partial dislocation emission from a boundary. We show that the nucleation stress for a Shockley partial is governed by size of the boundary defect and insensitive to grain size. We reveal a grain size regime in which the maximum value the stacking fault width attains increases with grain size.

  18. The width of the giant dipole resonance at finite temperature

    International Nuclear Information System (INIS)

    A method is proposed to evaluate the effect of the change of the Fermi sea on the width of the giant dipole resonance at finite temperature. In a schematic model it is found that, indeed, in 208Pb the width increases very sharply up to about T=4 MeV but shows a much weaker variation for higher temperature. (author) 26 refs., 7 figs., 2 tabs

  19. A direct measurement of W boson decay width

    CERN Document Server

    Abazov, V M; Abdesselam, A; Abolins, M; Abramov, V; Acharya, B S; Adams, D L; Adams, M; Ahmed, S N; Alexeev, G D; Alton, A; Alves, G A; Anderson, E W; Arnoud, Y; Avila, C; Baarmand, M M; Babintsev, V V; Babukhadia, L; Bacon, Trevor C; Baden, A; Baldin, B Yu; Balm, P W; Banerjee, S; Barberis, E; Baringer, P; Barreto, J; Bartlett, J F; Bassler, U; Bauer, D; Bean, A; Beaudette, F; Begel, M; Belyaev, A; Beri, S B; Bernardi, G; Bertram, I; Besson, A; Beuselinck, R; Bezzubov, V A; Bhat, P C; Bhatnagar, V; Bhattacharjee, M; Blazey, G; Blekman, F; Blessing, S; Böhnlein, A; Bozhko, N; Bolton, T A; Borcherding, F; Bos, K; Bose, T; Brandt, A; Breedon, R; Briskin, G; Brock, R; Brooijmans, G; Bross, A; Buchholz, D; Bühler, M; Büscher, V; Burtovoi, V S; Butler, J M; Canelli, F; Carvalho, W; Casey, D; Casilum, Z; Castilla-Valdez, H; Chakraborty, D; Chan, K M; Chekulaev, S V; Cho, D K; Choi, S; Chopra, S; Christenson, J H; Chung, M; Claes, D; Clark, A R; Coney, L; Connolly, B; Cooper, W E; Coppage, D; Crepe-Renaudin, S; Cummings, M A C; Cutts, D; Davis, G A; De, K; De Jong, S J; Demarteau, M; Demina, R; Demine, P; Denisov, D; Denisov, S P; Desai, S; Diehl, H T; Diesburg, M; Doulas, S; Ducros, Y; Dudko, L V; Duensing, S; Duflot, L; Dugad, S R; Duperrin, A; Dyshkant, A; Edmunds, D; Ellison, J; Eltzroth, J T; Elvira, V D; Engelmann, R; Eno, S; Eppley, G; Ermolov, P; Eroshin, O V; Estrada, J; Evans, H; Evdokimov, V N; Fahland, T; Fein, D; Ferbel, T; Filthaut, Frank; Fisk, H E; Fisyak, Yu; Flattum, E; Fleuret, F; Fortner, M; Fox, H; Frame, K C; Fu, S; Fuess, S; Gallas, E; Galjaev, A N; Gao, M; Gavrilov, V; Genik, R J; Genser, K; Gerber, C E; Gershtein, Yu; Gilmartin, R; Ginther, G; Gómez, B; Goncharov, P I; Gordon, H; Goss, L T; Gounder, K; Goussiou, A; Graf, N; Grannis, P D; Green, J A; Greenlee, H; Greenwood, Z D; Grinstein, S; Groer, L; Grünendahl, S; Sen-Gupta, A; Gurzhev, S N; Gutíerrez, G; Gutíerrez, P; Hadley, N J; Haggerty, H; Hagopian, S; Hagopian, V; Hall, R E; Hansen, S; Hauptman, J M; Hays, C; Hebert, C; Hedin, D; Heinmiller, J M; Heinson, A P; Heintz, U; Hildreth, M D; Hirosky, R; Hobbs, J D; Hoeneisen, B; Huang, Y; Iashvili, I; Illingworth, R; Ito, A S; Jaffré, M; Jain, S; Jesik, R; Johns, K; Johnson, M; Jonckheere, A; Jöstlein, H; Juste, A; Kahl, W; Kahn, S; Kajfasz, E; Kalinin, A M; Karmanov, D; Karmgard, D; Kehoe, R; Khanov, A; Kharchilava, A I; Kim, S K; Klima, B; Knuteson, B; Ko, W; Kohli, J M; Kostritskii, A V; Kotcher, J; Kothari, B; Kotwal, A V; Kozelov, A V; Kozlovskii, E A; Krane, J; Krishnaswamy, M R; Krivkova, P; Krzywdzinski, S; Kubantsev, M A; Kuleshov, S; Kulik, Y; Kunori, S; Kupco, A; Kuznetsov, V E; Landsberg, G L; Lee, W M; Leflat, A; Leggett, C; Lehner, F; Leonidopoulos, C; Li, J; Li, Q Z; Lima, J G R; Lincoln, D; Linn, S L; Linnemann, J; Lipton, R; Lucotte, A; Lueking, L; Lundstedt, C; Luo, C; Maciel, A K A; Madaras, R J; Malyshev, V L; Manankov, V; Mao, H S; Marshall, T; Martin, M I; Mayorov, A A; McCarthy, R; McMahon, T; Melanson, H L; Merkin, M; Merritt, K W; Miao, C; Miettinen, H; Mihalcea, D; Mishra, C S; Mokhov, N V; Mondal, N K; Montgomery, H E; Moore, R W; Mostafa, M; Da Motta, H; Mutaf, Y; Nagy, E; Nang, F; Narain, M; Narasimham, V S; Naumann, N A; Neal, H A; Negret, J P; Nomerotski, A; Nunnemann, T; O'Neil, D; Oguri, V; Olivier, B; Oshima, N; Padley, P; Pan, L J; Papageorgiou, K; Parashar, N; Partridge, R; Parua, N; Paterno, M; Patwa, A; Pawlik, B; Peters, O; Petroff, P; Piegaia, R; Pope, B G; Popkov, E; Prosper, H B; Protopopescu, S D; Przybycien, M B; Qian, J; Raja, R; Rajagopalan, S; Ramberg, E; Rapidis, P A; Reay, N W; Reucroft, S; Ridel, M; Rijssenbeek, M; Rizatdinova, F K; Rockwell, T; Roco, M T; Royon, C; Rubinov, P; Ruchti, R; Rutherfoord, J; Sabirov, B M; Sajot, G; Santoro, A F S; Sawyer, L; Schamberger, R D; Schellman, H; Schwartzman, A; Sen, N; Shabalina, E; Shivpuri, R K; Shpakov, D; Shupe, M; Sidwell, R A; Simák, V; Singh, H; Sirotenko, V I; Slattery, P F; Smith, E; Smith, R P; Snihur, R; Snow, G R; Snow, J; Snyder, S; Solomon, J; Song, Y; Sorin, V; Sosebee, M; Sotnikova, N; Soustruznik, K; Souza, M; Stanton, N R; Steinbruck, G; Stephens, R W; Stoker, D; Stolin, V; Stone, A; Stoyanova, D A; Strang, M A; Strauss, M; Strovink, M; Stutte, L; Sznajder, A; Talby, M; Taylor, W; Tentindo-Repond, S; Tripathi, S M; Trippe, T G; Turcot, A S; Tuts, P M; Vaniev, V; Van Kooten, R; Varelas, N; Vertogradov, L S; Villeneuve-Séguier, F; Volkov, A A; Vorobev, A P; Wahl, H D; Wang, H; Wang, Z M; Warchol, J; Watts, G; Wayne, M; Weerts, H; White, A; White, J T; Whiteson, D; Wijngaarden, D A; Willis, S; Wimpenny, S J; Womersley, J; Wood, D R; Xu, Q; Yamada, R; Yamin, P; Yasuda, T; Yatsunenko, Y A; Yip, K; Youssef, S; Yu, J; Zanabria, M; Zhang, X; Zheng, H; Zhou, B; Zhou, Z; Zielinski, M; Zieminska, D; Zieminski, A; Zutshi, V; Zverev, E G; Zylberstejn, A

    2002-01-01

    Based on 85 pb$^{-1}$ data of \\ppbar collisions at $\\sqrt{s}=1.8$ \\tev\\ collected using the D{\\O}detector at Fermilab during the 1994-1995 run of the Tevatron, we present a direct measurement of the total decay width of the \\wb\\ boson, $\\Gamma_W$. The width is determined from the transverse mass spectrum in the $W \\to e+\

  20. Quantifying River Widths of North America from Satellite Imagery

    Science.gov (United States)

    Allen, G. H.; Pavelsky, T.; Miller, Z.

    2013-12-01

    River width is a fundamental predictor variable in many hydrologic, geomorphic, and biogeochemical models, yet current large-scale models rely on theoretical hydraulic geometry relationships that do not fully capture natural variability in river form. Here we present the first high-resolution dataset of long-term mean width of North American rivers wider than 30 m. The dataset contains 7.93 million georeferenced width measurements derived from Landsat TM and ETM+ imagery that were acquired when rivers were most likely to be at mean discharge. We built the dataset by developing an automated procedure that selects and downloads raw imagery, creates cloud-free normalized difference water index images, histogram balances and mosaics them together, and produces a water mask using a dynamic water-land threshold technique. We then visually inspected and corrected the mask for errors and used RivWidth software to calculate river width at each river centerline pixel. We validated our dataset using >1000 United States Geological Survey and Water Survey of Canada in situ gauge station measurements. Error analysis shows a robust relationship between the remotely sensed widths and in situ gauge measurements with an r 2 = 0.86 (Spearman's = 0.81) and a mean absolute error of 27.5 m. We find that North American river widths lie on logarithmic frequency curve with some notable exceptions at widths models. Our results also allow for the characterization of the extent of rivers likely to be observable by the planned Surface Water and Ocean Topography (SWOT) satellite mission.

  1. SM Higgs decay branching ratios and total Higgs width

    CERN Multimedia

    Daniel Denegri

    2001-01-01

    Upper: Higgs decay ratios as a function of Higgs mass. The largest branching ratio is not necessarily the most usefull one. The most usefull ones are gamma gamma bbar ZZ and WW as in those modes latter signal to background ratios can be achieved. Lower: Total Higgs decay width versus Higgs mass. At low masses the natural width is extremely small, thus observability depends on instrumental resolution primarily.

  2. Echo width of foam supports used in scattering measurements

    DEFF Research Database (Denmark)

    Appel-Hansen, JØrgen; Solodukhov, V. V.

    1979-01-01

    Theoretically and experimentally determined echo widths of dielectric cylinders having circular, triangular, and quadratic cross sections have been compared. The cylinders were made of foam material having a relative dielectric constant of about 1.035. The purpose of the investigation was to find a cross section with a small echo width. The result can be used in selecting a proper support for test objects in backscattering measurement studies.

  3. Comprehensive intermaxillary tooth width proportion of Bangkok residents

    Directory of Open Access Journals (Sweden)

    Somchai Manopatanakul

    2011-04-01

    Full Text Available Proper occlusion depends on the correct width ratio between upper and lower teeth, known as Bolton's ratio. In fact, this ratio can be calculated for each pair of teeth from the central incisor to the first permanent molar. This set of ratios, known as comprehensive cumulative percentage ratios (CPRs, can be used not only to determine which tooth or teeth have a tooth width discrepancy, but can also enable the partial graphical analysis of tooth width discrepancy when there is agenesis of certain permanent teeth. Although CPRs have been calculated for Caucasians, tooth width is known to vary depending on racial origin. Therefore, a test of differences between racial groups should be carried out. If these ratios of the Caucasians and Bangkokians are significantly different, the ratio of the Bangkokians is recommended. The objective of this study was to measure tooth size disproportion for Thai patients and to calculate a corresponding set of CPRs. Thirty-seven pairs of dental models were made from a group of Bangkok residents with normal occlusion. Mesiodistal tooth width was measured for each model. The intra- and inter-examiner measurement errors were ascertained as insignificant (p > 0.05. CPRs were then calculated and compared to those derived from other studies. Ten of thirteen CPRs were significantly different from corresponding values derived from Caucasians. We conclude that tooth width ratios vary between different racial groups, and therefore that these should be calculated specifically for each patient racial group.

  4. Comprehensive intermaxillary tooth width proportion of Bangkok residents

    Scientific Electronic Library Online (English)

    Somchai, Manopatanakul; Narumon, Watanawirun.

    2011-04-01

    Full Text Available Proper occlusion depends on the correct width ratio between upper and lower teeth, known as Bolton's ratio. In fact, this ratio can be calculated for each pair of teeth from the central incisor to the first permanent molar. This set of ratios, known as comprehensive cumulative percentage ratios (CPR [...] s), can be used not only to determine which tooth or teeth have a tooth width discrepancy, but can also enable the partial graphical analysis of tooth width discrepancy when there is agenesis of certain permanent teeth. Although CPRs have been calculated for Caucasians, tooth width is known to vary depending on racial origin. Therefore, a test of differences between racial groups should be carried out. If these ratios of the Caucasians and Bangkokians are significantly different, the ratio of the Bangkokians is recommended. The objective of this study was to measure tooth size disproportion for Thai patients and to calculate a corresponding set of CPRs. Thirty-seven pairs of dental models were made from a group of Bangkok residents with normal occlusion. Mesiodistal tooth width was measured for each model. The intra- and inter-examiner measurement errors were ascertained as insignificant (p > 0.05). CPRs were then calculated and compared to those derived from other studies. Ten of thirteen CPRs were significantly different from corresponding values derived from Caucasians. We conclude that tooth width ratios vary between different racial groups, and therefore that these should be calculated specifically for each patient racial group.

  5. Crack width monitoring of concrete structures based on smart film

    Science.gov (United States)

    Zhang, Benniu; Wang, Shuliang; Li, Xingxing; Zhang, Xu; Yang, Guang; Qiu, Minfeng

    2014-04-01

    Due to its direct link to structural security, crack width is thought to be one of the most important parameters reflecting damage conditions of concrete structures. However, the width problem is difficult to solve with the existing structural health monitoring methods. In this paper, crack width monitoring by means of adhering enameled copper wires with different ultimate strains on the surface of structures is proposed, based on smart film crack monitoring put forward by the present authors. The basic idea of the proposed method is related to a proportional relationship between the crack width and ultimate strain of the broken wire. Namely, when a certain width of crack passes through the wire, some low ultimate strain wires will be broken and higher ultimate strain wires may stay non-broken until the crack extends to a larger scale. Detection of the copper wire condition as broken or non-broken may indicate the width of the structural crack. Thereafter, a multi-layered stress transfer model and specimen experiment are performed to quantify the relationship. A practical smart film is then redesigned with this idea and applied to Chongqing Jiangjin Yangtze River Bridge.

  6. Violation of the gauge equivalence

    CERN Document Server

    Khrapko, R I

    2001-01-01

    F. V. Gubarev et al. (``On the significance of the vector potential squared'', Phys. Rev. Lett. 86, 2220) have argued that the minimum value of the volume integral of the vector potential squared may have physical meaning, in defiance of the gauge equivalence of potentials. Earlier, R. I. Khrapko proposed a gauge noninvariant electrodynamics spin tensor (``Spin density of electromagnetic waves'', [1]). The standard electrodynamics spin tensor is zero. Here we point out that the Biot-Savarat formula uniquely results in a preferred, "true" vector potential field which is generated from a given magnetic field. A similar integral formula uniquely permits to find a "true" scalar potential field generated from a given electric field even in the case of a nonpotential electric field. We say that an exterior derivative of a differential form is the boundary of this form and the integration of a form results in a new form named the generation. Generating from a generation yields zero. A boundary is closed. A generatio...

  7. A Measurement of the Total Width, the Electronic Width and the Mass of the Upsilon(10580) Resonance

    CERN Document Server

    Aubert, Bernard; Abe, T; Abrams, G S; Adye, T; Ahmed, S; Alam, M S; Albert, J; Aleksan, Roy; Allison, J; Altenburg, D; Andreotti, M; Angelini, C; Anulli, F; Aston, D; Azzolini, V; Baak, M A; Back, J J; Bailey, S; Baldini-Ferroli, R; Band, H R; Banerjee, Sw; Barate, R; Barlow, N R; Barlow, R J; Bartoldus, R; Batignani, G; Bauer, J M; Beck, T W; Behera, P K; Bellini, F; Benayoun, M; Berger, N; Beringer, J; Bernard, D; Berryhill, J W; Best, D; Bettarini, S; Bettoni, D; Bevan, A J; Bhimji, W; Bianchi, F; Biasini, M; Blanc, F; Blaylock, G; Blinov, V E; Bloom, P; Bondioli, M; Bonneaud, G R; Borean, C; Borgland, A W; Bosisio, L; Boutigny, D; Bowerman, D A; Boyarski, A M; Boyd, J T; Bozzi, C; Brandt, T; Brau, B; Brau, J E; Breon, A B; Briand, H; Brigljevic, V; Brochard, F; Brose, J; Brown, C L; Brown, C M; Brown, D; Brown, D N; Bruinsma, M; Brunet, S; Bucci, F; Buchanan, C; Buchmüller, O L; Bugg, W; Bukin, A D; Burchat, Patricia R; Button-Shafer, J; Buzzo, A; Bóna, M; Cahn, R N; Calabrese, R; Calcaterra, A; Calderini, G; Campagnari, C; Capra, R; Carpinelli, M; Cartaro, C; Cavallo, N; Cavoto, G; Chao, M; Charles, E; Chauveau, J; Chen, E; Chen, J C; Chen, S; Cheng, C H; Chevalier, N; Christ, S; Cibinetto, G; Clark, P J; Cochran, J; Cohen-Tanugi, J; Colberg, T; Colecchia, F; Coleman, J P; Contri, R; Convery, M R; Cote-Ahern, D; Cottingham, W N; Coupal, D P; Cowan, G; Cowan, R; Crawley, H B; Cremaldi, L M; Crosetti, G; Dahmes, B; Dallapiccola, C; Danielson, N; Dasu, S; Datta, M; Dauncey, P D; David, P; Davier, M; Davis, C L; Day, C T; De Groot, N; De Nardo, Gallieno; De Sangro, R; Del Buono, L; Del Gamba, V; Del Re, D; Della Ricca, G; Di Lodovico, F; Dickopp, M; Dittongo, S; Donald, M; Dong, D; Dorfan, J; Dorigo, A; Dubitzky, R S; Dubois-Felsmann, G P; Dujmic, D; Dunwoodie, W M; Dvoretskii, A; Eckmann, R; Edwards, A J; Egede, U; Eichenbaum, A M; Eigen, G; Eisner, A M; Elmer, P; Emery, S; Ernst, J A; Eschenburg, V; Eschrich, I; Fabozzi, F; Faccini, R; Falciai, D; Farbin, A; Ferrarotto, F; Ferroni, F; Field, R C; Finocchiaro, G; Fisher, A; Flack, R L; Flächer, H U; Flood, K T; Ford, K; Ford, W T; Forti, A C; Forti, F; Fortin, D; Franek, B J; Frey, R; Fry, J R; Gabathuler, Erwin; Gabriel, T A; Gaidot, A; Gaillard, J M; Gaillard, J R; Galeazzi, F; Gallo, F; Gamba, D; Gamet, R; Gan, K K; Ganzhur, S F; Gaspero, M; Gatto, C; Geddes, N I; George, S; Gill, M S; Giorgi, M A; Giraud, P F; Gladney, L; Glanzman, T; Godang, R; Goetzen, K; Golubev, V B; Gopal, G P; Gowdy, S J; Grancagnolo, S; Graugès-Pous, E; Green, M G; Grenier, G J; Grenier, P; Gritsan, A V; Grosdidier, G; Groysman, Y; Guo, Q H; Hadavand, H K; Hadig, T; Haire, M; Halyo, V; Hamel de Monchenault, G; Hamon, O; Harrison, P F; Harrison, T J; Hart, P A; Hartfiel, B L; Harton, J L; Hast, C; Hauke, A; Hawkes, C M; Hearty, C; Held, T; Hertzbach, S S; Heusch, C A; Hicheur, A; Hill, E J; Hitlin, D G; Hodgkinson, M C; Honscheid, K; Hrynóva, T; Hu, T; Hufnagel, D; Höcker, A; Innes, W R; Ivanchenko, V N; Izen, J M; Jackson, F; Jackson, P D; Jacobsen, R G; Jawahery, A; Jayatilleke, S M; Jessop, C P; John, M J J; Johnson, J R; Judd, D; Kadel, R W; Kadyk, J; Kagan, H; Karyotakis, Yu; Kass, R; Kay, M; Kelly, M P; Kelsey, M H; Kerth, L T; Khan, A; Kim, H; Kim, P; Kirkby, D; Kitayama, I; Knowles, D J; Koch, H; Kocian, M L; Kofler, R; Kolomensky, Yu G; Koptchev, V B; Kovalskyi, D; Kowalewski, R V; Kozanecki, Witold; Kral, J F; Kravchenko, E A; Krishnamurthy, M; Kroeger, R; Kukartsev, G; Kurup, A; Kutter, P E; Kuznetsova, N; Kyberd, P; La Vaissière, C de; Lacker, H M; Lae, C K; Lafferty, G D; Lamsa, J; Lanceri, L; Lange, D J; Langenegger, U; Langer, M; Lankford, A J; Laplace, S; Latham, T E; Lavin, D; Lazzaro, A; Le Clerc, C; Le Diberder, F R; Lee, S J; Lees, J P; Legendre, M; Leith, D W G S; Lepeltier, V; Leruste, P; Levesque, J A; Levi, M E; Levy, S L; Lewandowski, B; Li, H; Lillard, V; Lista, L; Liu, R; Lo Vetere, M; LoSecco, J M; Lockman, W S; London, G W; Long, O; Lou, X C; Lu, A; Luitz, S; Luppi, E; Lusiani, A; Lutz, A M; Lynch, G; Lynch, H L; Lyon, A J; Lü, C; Lüth, V; MacFarlane, D B; MacKay, C; Macri, M; Mallik, U; Maly, E; Mancinelli, G; Mandelkern, M A; Manfredi, P F; Mangeol, D J J; Marchiori, G; Margoni, M; Marker, C E; Marsiske, H; Martínez-Vidal, F; Mattison, T S; Mayer, B; Mazur, M A; Mazzoni, M A; McKemey, A K; McKenna, J A; McMahon, T R; Meadows, B T; Messner, R; Meyer, T I; Meyer, W T; Miftakov, V; Mihályi, A; Mir, L M; Mohapatra, A K; Mommsen, R K; Monge, M R; Moore, T B; Morandin, M; Morgan, S E; Morganti, M; Morganti, S; Morii, M; Morton, G W; Muheim, F; Müller, D R; Müller-Pfefferkorn, R; Narsky, I; Nash, J A; Nauenberg, U; Neal, H; Negrini, M; Neri, N; Nicholson, H; Nogowski, R; O'Grady, C P; Ocariz, J; Oddone, P J; Ofte, I; Olaiya, E O; Olivas, A; Olsen, J; Onuchin, A P; Orimoto, T J; Otto, S; Ozcan, V E; Paar, H P

    2003-01-01

    We present a preliminary measurement of the resonance parameters of the Upsilon(10580) resonance with the BABAR detector at the SLAC PEP-II asymmetric B factory. We measure the total decay width to be (20.7 +- 1.6 +- 2.5) MeV, the partial electronic width to be (0.321 +- 0.017 +- 0.029) kev and the mass to be (10.5793 +- 0.0004 +- 0.0012) GeV.

  8. ??????–???????Kolmogorov??????????????? The Beam-Width Spread and Directionality of Partially Coherent Hermite-Ganssian Beams Propagating through Non-Kolmogorov Atmospheric Turbulence*

    Directory of Open Access Journals (Sweden)

    ???

    2013-05-01

    Full Text Available ???????–???????Kolmogorov????????????–??(H-G?????Kolmogorov????????????????????????????H-G??????????????????????????????????????????????????????0???????m?n???????H-G???????????????????????0????????????z??????????????????0???????H-G?????????????????????H-G???????Kolmogorov???????????????????????????????H-G?????????H-G???????–????(GSM????????????????Kolmogorov?????????????????????????????????? Based on the extended Huygens-Fresnel principle and non-Kolmogorov spectrum, analytical expressions for the beam-width spread of partially coherent Hermite-Ganssian (H-G beams propagating through non-Kolmogorov atmospheric turbulence are derived, and used to study the beam-width spreading and directionality of partially coherent H-G beams propagating through non-Kolmogorov atmospheric turbulence. The relative width is introduced to quantitatively describe the resistance of a beam to atmospheric turbulence. It is shown that the smaller the spatial correlation length ?0, and the larger the beam order m, n, and the less the beam-width spreading of partially coherent H-G beams is affected by non-Kolmogorov atmospheric turbulence. The influence of turbulence on beam-width spreading depends on the waist width ?0 and propagation distance z, when the propagation distance is sufficiently long, the smaller the waist width ?0, the less the beam-width spreading of partially coherent H-G beams is affected by non-Kolmogorov atmospheric turbulence. The beam width of partially coherent H-G beams through non-Kolmogorov atmospheric turbulence increase with the increasing exponent parameter ?, then decrease with increasing ?. There exist equivalent partially coherent and fully coherent H-G beams, GSM beams, which have the same directionality as a fully coherent Gaussian laser beam in free space and in non-Kolmogorov atmospheric turbulence. The results are interpreted physically.  

  9. Qualitative Logics and Equivalences for Probabilistic Systems

    CERN Document Server

    Chatterjee, Krishnendu; Faella, Marco; Legay, Axel

    2009-01-01

    We investigate logics and equivalence relations that capture the qualitative behavior of Markov Decision Processes (MDPs). We present Qualitative Randomized CTL (QRCTL): formulas of this logic can express the fact that certain temporal properties hold over all paths, or with probability 0 or 1, but they do not distinguish among intermediate probability values. We present a symbolic, polynomial time model-checking algorithm for QRCTL on MDPs. The logic QRCTL induces an equivalence relation over states of an MDP that we call qualitative equivalence: informally, two states are qualitatively equivalent if the sets of formulas that hold with probability 0 or 1 at the two states are the same. We show that for finite alternating MDPs, where nondeterministic and probabilistic choices occur in different states, qualitative equivalence coincides with alternating bisimulation, and can thus be computed via efficient partition-refinement algorithms. On the other hand, in non-alternating MDPs the equivalence relations cann...

  10. Monitoring the width of hydraulic fractures with acoustic waves

    Energy Technology Data Exchange (ETDEWEB)

    Groenenboom, J.; Fokkema, J.T. [Delft Univ. of Technology (Netherlands)

    1998-01-01

    For a direct determination of the width, the resolution of the signal is required to distinguish the reflections that are related with two distinct fluid/solid interfaces delimiting the hydraulic fracture from its solid embedding. To make this distinction, the solid/fluid interfaces must be separated at least one eighth of a wavelength and represent sufficient impedance contrast. The applicability of the indirect dispersion measurement method however, extends to a fracture width that is in the order of 1% of the incident wavelength. The time-lapse ultrasonic measurements allow one to relate the small difference in arrival time and amplitude between two measurements solely to the small changes in the width of the fracture. Additional experimental data show that shear waves are completely shadowed by hydraulic fractures, indicating that there is no acoustic contact mechanism at the fracture interface. Therefore the authors think it is appropriate to use a thin fluid-filled layer model for these hydraulic fractures instead of the standard empirically oriented linear slip model. Nevertheless, the thin layer model is consistent with the linear-slip model, if interpreted correctly. A comparison of width measurements inside the well-bore and width estimates by means of dispersion measurements close to the wellbore shows that the method can be successfully applied, at least under laboratory conditions, and that small changes in the width of the fracture are directly expressed in the dispersion of the transmitted signal. This opens the way for the important new application of width monitoring of hydraulic fractures.

  11. Equivalent Simplification Method of Micro-Grid

    OpenAIRE

    Cai Changchun; Cao Xiangqin

    2013-01-01

    The paper concentrates on the equivalent simplification method for the micro-grid system connection into distributed network. The equivalent simplification method proposed for interaction study between micro-grid and distributed network. Micro-grid network, composite load, gas turbine synchronous generation, wind generation are equivalent simplification and parallel connect into the point of common coupling. A micro-grid system is built and three phase and single phase grounded faults are per...

  12. Bisimulation Equivalence of First-Order Grammars

    OpenAIRE

    Jancar, Petr

    2014-01-01

    A decidability proof for bisimulation equivalence of first-order grammars (finite sets of labelled rules for rewriting roots of first-order terms) is presented. The equivalence generalizes the DPDA (deterministic pushdown automata) equivalence, and the result corresponds to the result achieved by Senizergues (1998, 2005) in the framework of equational graphs, or of PDA with restricted epsilon-steps. The framework of classical first-order terms seems particularly useful for p...

  13. Perverse Equivalences and Brou\\'e's Conjecture

    CERN Document Server

    Craven, David A

    2010-01-01

    We give a new approach to the construction of derived equivalences between blocks of finite groups, based on perverse equivalences, in the setting of Brou\\'e's conjecture. We provide in particular local and global perversity data describing the principal blocks and the derived equivalences for a number of finite simple groups with Sylow subgroups C3xC3. We also examine extensions to automorphism groups in a general setting.

  14. About Orientifold Planar Equivalence on the Lattice

    CERN Document Server

    Patella, A

    2006-01-01

    The orientifold planar equivalence is the equivalence in the large-N limit of the bosonic sectors of the super Yang-Mills and the QCD with a quark in the antisymmetric representation. I give a sketch of the proof of the orientifold planar equivalence in the strong-coupling and large-mass phase on the lattice. It is still matter of discussion, if its validity extends also in the continuum limit.

  15. Behavioural equivalence for infinite systems - Partially decidable!

    DEFF Research Database (Denmark)

    Sunesen, Kim; Nielsen, Mogens

    1996-01-01

    For finite-state systems non-interleaving equivalences are computationally at least as hard as interleaving equivalences. In this paper we show that when moving to infinite-state systems, this situation may change dramatically. We compare standard language equivalence for process description languages with two generalizations based on traditional approaches capturing non-interleaving behaviour, pomsets representing global causal dependency, and locality representing spatial distribution of events. We first study equivalences on Basic Parallel Processes, BPP, a process calculus equivalent to communication free Petri nets. For this simple process language our two notions of non-interleaving equivalences agree. More interestingly, we show that they are decidable, contrasting a result of Hirshfeld that standard interleaving language equivalence is undecidable. Our result is inspired by a recent result of Esparza and Kiehn, showing the same phenomenon in the setting of model checking. We follow up investigating towhich extent the result extends to larger subsets of CCS and TCSP. We discover a significant difference between our non-interleaving equivalences. We show that for a certain non-trivial subclass of processes between BPP and TCSP, not only are the two equivalences different, but one (locality) is decidable whereas the other (pomsets) is not. The decidability result for locality is proved by a reduction to the reachability problem for Petri nets.

  16. Capacitor charging FET switcher with controller to adjust pulse width

    Science.gov (United States)

    Mihalka, Alex M. (Livermore, CA)

    1986-01-01

    A switching power supply includes an FET full bridge, a controller to drive the FETs, a programmable controller to dynamically control final output current by adjusting pulse width, and a variety of protective systems, including an overcurrent latch for current control. Power MOSFETS are switched at a variable frequency from 20-50 kHz to charge a capacitor load from 0 to 6 kV. A ferrite transformer steps up the DC input. The transformer primary is a full bridge configuration with the FET switches and the secondary is fed into a high voltage full wave rectifier whose output is connected directly to the energy storage capacitor. The peak current is held constant by varying the pulse width using predetermined timing resistors and counting pulses. The pulse width is increased as the capacitor charges to maintain peak current. A digital ripple counter counts pulses, and after the desired number is reached, an up-counter is clocked. The up-counter output is decoded to choose among different resistors used to discharge a timing capacitor, thereby determining the pulse width. A current latch shuts down the supply on overcurrent due to either excessive pulse width causing transformer saturation or a major bridge fault, i.e., FET or transformer failure, or failure of the drive circuitry.

  17. The dosimetric impact of leaf interdigitation and leaf width on VMAT treatment planning in Pinnacle: comparing Pareto fronts

    International Nuclear Information System (INIS)

    To evaluate in an objective way the effect of leaf interdigitation and leaf width on volumetric modulated arc therapy plans in Pinnacle. Three multileaf collimators (MLCs) were modeled: two 10 mm leaf width MLCs, with and without interdigitating leafs, and a 5 mm leaf width MLC with interdigitating leafs. Three rectum patients and three prostate patients were used for the planning study. In order to compare treatment techniques in an objective way, a Pareto front comparison was carried out. 200 plans were generated in an automated way, per patient per MLC model, resulting in a total of 3600 plans. From these plans, Pareto-optimal plans were selected which were evaluated for various dosimetric variables. The capability of leaf interdigitation showed little dosimetric impact on the treatment plans, when comparing the 10 mm leaf width MLC with and without leaf interdigitation. When comparing the 10 mm leaf width MLC with the 5 mm leaf width MLC, both with interdigitating leafs, improvement in plan quality was observed. For both patient groups, the integral dose was reduced by 0.6 J for the thin MLC. For the prostate patients, the mean dose to the anal sphincter was reduced by 1.8 Gy and the conformity of the V95% was reduced by 0.02 using the thin MLC. The V65% of the rectum was reduced by 0.1% and the dose homogeneity with 1.5%. For rectum patients, the mean dose to the bowel was reduced by 1.4 Gy and the mean dose to the bladder with 0.8 Gy for thean dose to the bladder with 0.8 Gy for the thin MLC. The conformity of the V95% was equivalent for the 10 and 5 mm leaf width MLCs for the rectum patients. We have objectively compared three types of MLCs in a planning study for prostate and rectum patients by analyzing Pareto-optimal plans which were generated in an automated way. Interdigitation of MLC leafs does not generate better plans using the SmartArc algorithm in Pinnacle. Changing the MLC leaf width from 10 to 5 mm generates better treatment plans although the clinical relevance remains to be proven. (paper)

  18. Local tree-width, excluded minors and approximation algorithms

    CERN Document Server

    Grohe, M

    2000-01-01

    The local tree-width of a graph G=(V,E) is the function ltw^G: N -> N that associates with every natural number r the maximal tree-width of an r-neighborhood in G. Our main graph theoretic result is a decomposition theorem for graphs with excluded minors that essentially says that such graphs can be decomposed into trees of graphs of bounded local tree-width. As an application of this theorem, we show that a number of combinatorial optimization problems, such as Minimum Vertex Cover, Minimum Dominating Set, and Maximum Independent Set have a polynomial time approximation scheme when restricted to a class of graphs with an excluded minor.

  19. Fast Width Detection in Corridor Using Hough Transform

    Directory of Open Access Journals (Sweden)

    Mehrdad Javadi

    2012-11-01

    Full Text Available For many robotics and smart car applications it is vitally important to calculate the width. The present paper proposes a new approach for finding the width of a corridor within a constructed image frame that would keep a robot on a safe track away from walls. The main advantage of this approach is less computation time and hence faster response for path recognition. In this new approach, the Hugh Transform technique is also used as the basis of the provided algorithm. Within the determination of corridor width, in order to avoid the accident in the future researches, some approaches such as identify open space, modeling and reconstruction of three-dimensional space, can also be used.

  20. Modelling the widths of fission observables in GEF

    Directory of Open Access Journals (Sweden)

    Schmidt K.-H.

    2013-03-01

    Full Text Available The widths of the mass distributions of the different fission channels are traced back to the probability distributions of the corresponding quantum oscillators that are coupled to the heat bath, which is formed by the intrinsic degrees of freedom of the fissioning system under the influence of pairing correlations and shell effects. Following conclusion from stochastic calculations of Adeev and Pashkevich, an early freezing due to dynamical effects is assumed. It is shown that the mass width of the fission channels in low-energy fission is strongly influenced by the zero-point motion of the corresponding quantum oscillator. The observed variation of the mass widths of the asymmetric fission channels with excitation energy is attributed to the energy-dependent properties of the heat bath and not to the population of excited states of the corresponding quantum oscillator.

  1. Tau-Equivalence and Equipercentile Equating.

    Science.gov (United States)

    Yen, Wendy M.

    1983-01-01

    Tau-equivalence means that two tests produce equal true scores for individuals but that the distribution of errors for the tests could be different. This paper examines the effect of performing equipercentile equating techniques on tau-equivalent tests. (JKS)

  2. Bisimulations Meet PCTL Equivalences for Probabilistic Automata

    OpenAIRE

    Song, Lei; Zhang, Lijun; Godskesen, Jens Chr.; Nielson, Flemming

    2011-01-01

    Probabilistic automata (PAs) have been successfully applied in formal verification of concurrent and stochastic systems. Efficient model checking algorithms have been studied, where the most often used logics for expressing properties are based on probabilistic computation tree logic (PCTL) and its extension PCTL^*. Various behavioral equivalences are proposed, as a powerful tool for abstraction and compositional minimization for PAs. Unfortunately, the equivalences are well...

  3. Shift adn width of HeII lines

    International Nuclear Information System (INIS)

    Based on a quantum statistical many-particle theory, the shift and the width of some He II lines have been evaluated. Ion dynamics have been treated within the model microfield method. Furthermore, fine structure splitting has been taken into account in order to check whether this effect is the cause for the existing large discrepancies between theoretical and experimental line widths. Besides the electronic contributions to the line shift, the shift due to the inhomogeneities of the ionic microfield as well as that due to the quadratic Stark effect has been included. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  4. Fjords in viscous fingering: selection of width and opening angle

    CERN Document Server

    Ristroph, L; Mineev-Weinstein, M B; Swinney, H L; Ristroph, Leif; Thrasher, Matthew; Mineev-Weinstein, Mark B.; Swinney, Harry L.

    2005-01-01

    Our experiments on viscous fingering of air into oil contained between closely spaced plates reveal two selection rules for the fjords of oil that separate fingers of air. (Fjords are the building blocks of solutions of the zero surface tension Laplacian growth equation.) Experiments in rectangular and circular geometries yield fjords with base widths 1/2 lambda_c, where lambda_c is the most unstable wavelength from a linear stability analysis. Further, fjords open at an angle of 8.0 degrees plus or minus 1.0 degree. These selection rules hold for a wide range of pumping rates and fjord lengths, widths, and directions.

  5. On collisional emission line widths in electron channeling

    International Nuclear Information System (INIS)

    Expression for collisional widths of cross section energy levels are obtained withing the frames of study of relativistic electron emission characteristics diring plane channeling. Attention is paid to the necessity of summarizing by finite states and averaging by initial ones. The necessity of potential modification by application of the Doyle-Terner approximation for low r during calculations is shown. The data on emission line widths by axial channeling with an account of influence of crystal atom heat shift correlations and detector response function are presented Numerical calculations and comparison with experimental results are carried out. Fair agreement with the experimental data is achieved

  6. Widths of the isobaric analog state of 208Pb

    International Nuclear Information System (INIS)

    Both escape and spreading widths are evaluated microscopically in a consistent framework for the isobaric analog of the 206Pb ground state. A TDA Green function is obtained within the space of discretized J=0+ proton-particle neutron-hole configurations using the Skyrme interaction. Couplings of these configurations with continuum and more complicated configurations are included into TDA matrix elements with a form of energy dependent terms. The energy and the widths of the isobaric analog resonance are obtained as a result of the matrix diagonalization. Comparison is made of the results with the former theoretical calculations as well as experimental data. (orig.)

  7. Direct measurement of the W boson decay width

    Science.gov (United States)

    Abazov, V. M.; Abbott, B.; Abdesselam, A.; Abolins, M.; Abramov, V.; Acharya, B. S.; Adams, D. L.; Adams, M.; Ahmed, S. N.; Alexeev, G. D.; Alton, A.; Alves, G. A.; Anderson, E. W.; Arnoud, Y.; Avila, C.; Baarmand, M. M.; Babintsev, V. V.; Babukhadia, L.; Bacon, T. C.; Baden, A.; Baldin, B.; Balm, P. W.; Banerjee, S.; Barberis, E.; Baringer, P.; Barreto, J.; Bartlett, J. F.; Bassler, U.; Bauer, D.; Bean, A.; Beaudette, F.; Begel, M.; Belyaev, A.; Beri, S. B.; Bernardi, G.; Bertram, I.; Besson, A.; Beuselinck, R.; Bezzubov, V. A.; Bhat, P. C.; Bhatnagar, V.; Bhattacharjee, M.; Blazey, G.; Blekman, F.; Blessing, S.; Boehnlein, A.; Bojko, N. I.; Bolton, T. A.; Borcherding, F.; Bos, K.; Bose, T.; Brandt, A.; Breedon, R.; Briskin, G.; Brock, R.; Brooijmans, G.; Bross, A.; Buchholz, D.; Buehler, M.; Buescher, V.; Burtovoi, V. S.; Butler, J. M.; Canelli, F.; Carvalho, W.; Casey, D.; Casilum, Z.; Castilla-Valdez, H.; Chakraborty, D.; Chan, K. M.; Chekulaev, S. V.; Cho, D. K.; Choi, S.; Chopra, S.; Christenson, J. H.; Chung, M.; Claes, D.; Clark, A. R.; Coney, L.; Connolly, B.; Cooper, W. E.; Coppage, D.; Crépé-Renaudin, S.; Cummings, M. A.; Cutts, D.; Davis, G. A.; de, K.; de Jong, S. J.; Demarteau, M.; Demina, R.; Demine, P.; Denisov, D.; Denisov, S. P.; Desai, S.; Diehl, H. T.; Diesburg, M.; Doulas, S.; Ducros, Y.; Dudko, L. V.; Duensing, S.; Duflot, L.; Dugad, S. R.; Duperrin, A.; Dyshkant, A.; Edmunds, D.; Ellison, J.; Eltzroth, J. T.; Elvira, V. D.; Engelmann, R.; Eno, S.; Eppley, G.; Ermolov, P.; Eroshin, O. V.; Estrada, J.; Evans, H.; Evdokimov, V. N.; Fahland, T.; Fein, D.; Ferbel, T.; Filthaut, F.; Fisk, H. E.; Fisyak, Y.; Flattum, E.; Fleuret, F.; Fortner, M.; Fox, H.; Frame, K. C.; Fu, S.; Fuess, S.; Gallas, E.; Galyaev, A. N.; Gao, M.; Gavrilov, V.; Genik, R. J.; Genser, K.; Gerber, C. E.; Gershtein, Y.; Gilmartin, R.; Ginther, G.; Gómez, B.; Goncharov, P. I.; González Solís, J. L.; Gordon, H.; Goss, L. T.; Gounder, K.; Goussiou, A.; Graf, N.; Grannis, P. D.; Green, J. A.; Greenlee, H.; Greenwood, Z. D.; Grinstein, S.; Groer, L.; Grünendahl, S.; Gupta, A.; Gurzhiev, S. N.; Gutierrez, G.; Gutierrez, P.; Hadley, N. J.; Haggerty, H.; Hagopian, S.; Hagopian, V.; Hall, R. E.; Hansen, S.; Hauptman, J. M.; Hays, C.; Hebert, C.; Hedin, D.; Heinmiller, J. M.; Heinson, A. P.; Heintz, U.; Hildreth, M. D.; Hirosky, R.; Hobbs, J. D.; Hoeneisen, B.; Huang, Y.; Iashvili, I.; Illingworth, R.; Ito, A. S.; Jaffré, M.; Jain, S.; Jesik, R.; Johns, K.; Johnson, M.; Jonckheere, A.; Jöstlein, H.; Juste, A.; Kahl, W.; Kahn, S.; Kajfasz, E.; Kalinin, A. M.; Karmanov, D.; Karmgard, D.; Kehoe, R.; Khanov, A.; Kharchilava, A.; Kim, S. K.; Klima, B.; Knuteson, B.; Ko, W.; Kohli, J. M.; Kostritskiy, A. V.; Kotcher, J.; Kothari, B.; Kotwal, A. V.; Kozelov, A. V.; Kozlovsky, E. A.; Krane, J.; Krishnaswamy, M. R.; Krivkova, P.; Krzywdzinski, S.; Kubantsev, M.; Kuleshov, S.; Kulik, Y.; Kunori, S.; Kupco, A.; Kuznetsov, V. E.; Landsberg, G.; Lee, W. M.; Leflat, A.; Leggett, C.; Lehner, F.; Leonidopoulos, C.; Li, J.; Li, Q. Z.; Lima, J. G.; Lincoln, D.; Linn, S. L.; Linnemann, J.; Lipton, R.; Lucotte, A.; Lueking, L.; Lundstedt, C.; Luo, C.; Maciel, A. K.; Madaras, R. J.; Malyshev, V. L.; Manankov, V.; Mao, H. S.; Marshall, T.; Martin, M. I.; Mayorov, A. A.; McCarthy, R.; McMahon, T.; Melanson, H. L.; Merkin, M.; Merritt, K. W.; Miao, C.; Miettinen, H.; Mihalcea, D.; Mishra, C. S.; Mokhov, N.; Mondal, N. K.; Montgomery, H. E.; Moore, R. W.; Mostafa, M.; da Motta, H.; Mutaf, Y.; Nagy, E.; Nang, F.; Narain, M.; Narasimham, V. S.; Naumann, N. A.; Neal, H. A.; Negret, J. P.; Nomerotski, A.; Nunnemann, T.; O'Neil, D.; Oguri, V.; Olivier, B.; Oshima, N.; Padley, P.; Pan, L. J.; Papageorgiou, K.; Parashar, N.; Partridge, R.; Parua, N.; Paterno, M.; Patwa, A.; Pawlik, B.; Peters, O.; Pétroff, P.; Piegaia, R.; Pope, B. G.; Popkov, E.; Prosper, H. B.; Protopopescu, S.; Przybycien, M. B.; Qian, J.; Raja, R.; Rajagopalan, S.; Ramberg, E.; Rapidis, P. A.; Reay, N. W.; Reucroft, S.; Ridel, M.; Rijssenbeek, M.; Rizatdinova, F.; Rockwell, T.; Roco, M.; Royon, C.; Rubinov, P.; Ruchti, R.; Rutherfoord, J.; Sabirov, B. M.; Sajot, G.; Santoro, A.; Sawyer, L.; Schamberger, R. D.; Schellman, H.; Schwartzman, A.; Sen, N.; Shabalina, E.; Shivpuri, R. K.; Shpakov, D.; Shupe, M.; Sidwell, R. A.; Simak, V.; Singh, H.; Sirotenko, V.; Slattery, P.; Smith, E.; Smith, R. P.; Snihur, R.; Snow, G. R.; Snow, J.; Snyder, S.; Solomon, J.; Song, Y.; Sorín, V.; Sosebee, M.; Sotnikova, N.; Soustruznik, K.; Souza, M.; Stanton, N. R.; Steinbrück, G.; Stephens, R. W.; Stoker, D.; Stolin, V.; Stone, A.; Stoyanova, D. A.; Strang, M. A.; Strauss, M.; Strovink, M.; Stutte, L.; Sznajder, A.; Talby, M.; Taylor, W.; Tentindo-Repond, S.; Tripathi, S. M.; Trippe, T. G.

    2002-08-01

    Based on 85 pb-1 data of pp¯ collisions at (s)=1.8 TeV collected using the DØ detector at Fermilab during the 1994-1995 run of the Tevatron, we present a direct measurement of the total decay width of the W boson ?W. The width is determined from the transverse mass spectrum in the W-->e+?e decay channel and found to be ?W=2.23+0.15- 0.14(stat)+/-0.10(syst) GeV, consistent with the expectation from the standard model.

  8. Infinite time decidable equivalence relation theory

    CERN Document Server

    Coskey, Samuel

    2009-01-01

    We introduce an analog of the theory of Borel equivalence relations in which we study equivalence relations that are decidable by an infinite time Turing machine. The Borel reductions are replaced by the more general class of infinite time computable functions. Many basic aspects of the classical theory remain intact, with the added bonus that it becomes sensible to study some special equivalence relations whose complexity is beyond Borel or even analytic. We also introduce an infinite time generalization of the countable Borel equivalence relations, a key subclass of the Borel equivalence relations, and again show that several key properties carry over to the larger class. Lastly, we collect together several results from the literature regarding Borel reducibility which apply also to absolutely Delta_1^2 reductions, and hence to the infinite time computable reductions.

  9. Bisimulations meet PCTL equivalences for probabilistic automata

    DEFF Research Database (Denmark)

    Song, Lei; Zhang, Lijun

    2013-01-01

    Probabilistic automata (PAs) have been successfully applied in formal verification of concurrent and stochastic systems. Efficient model checking algorithms have been studied, where the most often used logics for expressing properties are based on probabilistic computation tree logic (PCTL) and its extension PCTL*. Various behavioral equivalences are proposed, as a powerful tool for abstraction and compositional minimization for PAs. Unfortunately, the equivalences are well-known to be sound, but not complete with respect to the logical equivalences induced by PCTL or PCTL*. The desire of a both sound and complete behavioral equivalence has been pointed out by Segala in [34], but remains open throughout the years. In this paper we introduce novel notions of strong bisimulation relations, which characterize PCTL and PCTL* exactly. We extend weak bisimulations that characterize PCTL and PCTL* without next operator, respectively. Further, we also extend the framework to simulation preorders. Thus, our paper bridges the gap between logical and behavioral equivalences and preorders in this setting.

  10. Beyond Language Equivalence on Visibly Pushdown Automata

    DEFF Research Database (Denmark)

    Srba, Jiri

    2009-01-01

    We study (bi)simulation-like preorder/equivalence checking on the class of visibly pushdown automata and its natural subclasses visibly BPA (Basic Process Algebra) and visibly one-counter automata. We describe generic methods for proving complexity upper and lower bounds for a number of studied preorders and equivalences like simulation, completed simulation, ready simulation, 2-nested simulation preorders/equivalences and bisimulation equivalence. Our main results are that all the mentioned equivalences and preorders are EXPTIME-complete on visibly pushdown automata, PSPACE-complete on visibly one-counter automata and P-complete on visibly BPA. Our PSPACE lower bound for visibly one-counter automata improves also the previously known DP-hardness results for ordinary one-counter automata and one-counter nets. Finally, we study regularity checking problems for visibly pushdown automata and show that they can be decided in polynomial time.

  11. Equivalence in Ventilation and Indoor Air Quality

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, Max; Walker, Iain; Logue, Jennifer

    2011-08-01

    We ventilate buildings to provide acceptable indoor air quality (IAQ). Ventilation standards (such as American Society of Heating, Refrigerating, and Air-Conditioning Enginners [ASHRAE] Standard 62) specify minimum ventilation rates without taking into account the impact of those rates on IAQ. Innovative ventilation management is often a desirable element of reducing energy consumption or improving IAQ or comfort. Variable ventilation is one innovative strategy. To use variable ventilation in a way that meets standards, it is necessary to have a method for determining equivalence in terms of either ventilation or indoor air quality. This study develops methods to calculate either equivalent ventilation or equivalent IAQ. We demonstrate that equivalent ventilation can be used as the basis for dynamic ventilation control, reducing peak load and infiltration of outdoor contaminants. We also show that equivalent IAQ could allow some contaminants to exceed current standards if other contaminants are more stringently controlled.

  12. Modified model of neutron resonances widths distributions. Results of reduced neutron widths approximation for mass region 35 ? A ? 249

    International Nuclear Information System (INIS)

    The distributions of the reduced neutron widths of s-, p- and d-resonances of nuclei of any type from nuclear mass region 35 ? A ? 249 were approximated with maximal precision by the model which presents experimental data set as a superposition of a maximum of four independent neutron amplitudes. Under the assumption that each of these amplitudes has the Gauss distribution with the unique maximum there were determined the most probable values of contribution of each amplitude in summary width distribution, their most probable mean values and dispersions. Comparison of the obtained ?2 values with value ?2 at description of the experimental data by one distribution of neutron amplitudes with best fitted parameters shows that all widths from more than 157 analyzed data sets can have different types of wave functions

  13. Scaling of divertor power footprint width in RF-heated type-III ELMy H-mode on the EAST superconducting tokamak

    International Nuclear Information System (INIS)

    Dedicated experiments for the scaling of divertor power footprint width have been performed in the ITER-relevant radio-frequency (RF)-heated H-mode scheme under the lower single null, double null and upper single null divertor configurations in the Experimental Advanced Superconducting Tokamak (EAST) under lithium wall coating conditioning. A strong inverse scaling of the edge localized mode (ELM)-averaged power fall-off width with the plasma current (equivalently the poloidal field) has been demonstrated for the attached type-III ELMy H-mode as ?q?Ip?1.05 by various heat flux diagnostics including the divertor Langmuir probes (LPs), infra-red (IR) thermograph and reciprocating LPs on the low-field side. The IR camera and divertor LP measurements show that ?q,IR??q,div-LPs/1.3=1.15Bp,omp?1.25, in good agreement with the multi-machine scaling trend during the inter-ELM phase between type-I ELMs or ELM-free enhanced D? (EDA). H-mode. However, the magnitude is nearly doubled, which may be attributed to the different operation scenarios or heating schemes in EAST, i.e., dominated by electron heating. It is also shown that the type-III ELMs only broaden the power fall-off width slightly, and the ELM-averaged width is representative for the inter-ELM period. Furthermore, the inverse Ip (Bp) scaling appears to be independent of the divertor configurations in EAST. The divertor power footprint integral width, fall-off width and dissipation width derived from EAST IR camera measurements follow the relation, ?int ? ?q + 1.64S, yielding ?intEAST=(1.39±0.03)?qEAST+(0.97±0.35) mm. Detailed analysis of these three characteristic widths was carried out to shed more light on their extrapolation to ITER. (paper)

  14. A Measurement of the Total Width, the Electronic Width, and the Mass of the Upsilon(10580) Resonance

    CERN Document Server

    Aubert, B; Boutigny, D; Couderc, F; Gaillard, J M; Hicheur, A; Karyotakis, Yu; Lees, J P; Tisserand, V; Zghiche, A; Palano, A; Pompili, A; Chen, J C; Qi, N D; Rong, G; Wang, P; Zhu, Y S; Eigen, G; Ofte, I; Stugu, B; Abrams, G S; Borgland, A W; Breon, A B; Brown, D N; Button-Shafer, J; Cahn, R N; Charles, E; Day, C T; Gill, M S; Gritsan, A V; Groysman, Y; Jacobsen, R G; Kadel, R W; Kadyk, J; Kerth, L T; Kolomensky, Yu G; Kukartsev, G; Le Clerc, C; Lynch, G; Merchant, A M; Mir, L M; Oddone, P J; Orimoto, T J; Pripstein, M; Roe, N A; Ronan, Michael T; Shelkov, V G; Telnov, A V; Wenzel, W A; Ford, K; Harrison, T J; Hawkes, C M; Morgan, S E; Watson, A T; Fritsch, M; Goetzen, K; Held, T; Koch, H; Lewandowski, B; Pelizaeus, M; Steinke, M; Boyd, J T; Chevalier, N; Cottingham, W N; Kelly, M P; Latham, T E; Wilson, F F; Çuhadar-Dönszelmann, T; Hearty, C; Mattison, T S; McKenna, J A; Thiessen, D; Kyberd, P; Teodorescu, L; Blinov, V E; Bukin, A D; Druzhinin, V P; Golubev, V B; Ivanchenko, V N; Kravchenko, E A; Onuchin, A P; Serednyakov, S I; Skovpen, Yu I; Solodov, E P; Yushkov, A N; Best, D; Bruinsma, M; Chao, M; Eschrich, I; Kirkby, D; Lankford, A J; Mandelkern, M A; Mommsen, R K; Röthel, W; Stoker, D P; Buchanan, C; Hartfiel, B L; Gary, J W; Shen, B C; Wang, K; Del Re, D; Hadavand, H K; Hill, E J; MacFarlane, D B; Paar, H P; Rahatlou, S; Sharma, V; Berryhill, J W; Campagnari, C; Dahmes, B; Levy, S L; Long, O; Lu, A; Mazur, M A; Richman, J D; Verkerke, W; Beck, T W; Eisner, A M; Heusch, C A; Lockman, W S; Schalk, T; Schmitz, R E; Schumm, B A; Seiden, A; Spradlin, P; Williams, D C; Wilson, M G; Albert, J; Chen, E; Dubois-Felsmann, G P; Dvoretskii, A; Hitlin, D G; Narsky, I; Piatenko, T; Porter, F C; Ryd, A; Samuel, A; Yang, S; Jayatilleke, S M; Mancinelli, G; Meadows, B T; Sokoloff, M D; Abe, T; Blanc, F; Bloom, P; Chen, S; Clark, P J; Ford, W T; Nauenberg, U; Olivas, A; Rankin, P; Smith, J G; Zhang, L; Chen, A; Harton, J L; Soffer, A; Toki, W H; Wilson, R J; Zeng, Q L; Altenburg, D; Brandt, T; Brose, J; Colberg, T; Dickopp, M; Feltresi, E; Hauke, A; Lacker, H M; Maly, E; Müller-Pfefferkorn, R; Nogowski, R; Otto, S; Petzold, A; Schubert, J; Schubert, Klaus R; Schwierz, R; Spaan, B; Sundermann, J E; Bernard, D; Bonneaud, G R; Brochard, F; Grenier, P; Schrenk, S; Thiebaux, C; Vasileiadis, G; Verderi, M; Bard, D J; Khan, A; Lavin, D; Muheim, F; Playfer, S; Andreotti, M; Azzolini, V; Bettoni, D; Bozzi, C; Calabrese, R; Cibinetto, G; Luppi, E; Negrini, M; Piemontese, L; Sarti, A; Treadwell, E; Baldini-Ferroli, R; Calcaterra, A; De Sangro, R; Finocchiaro, G; Patteri, P; Piccolo, M; Zallo, A; Buzzo, A; Capra, R; Contri, R; Crosetti, G; Lo Vetere, M; Macri, M; Monge, M R; Passaggio, S; Patrignani, C; Robutti, E; Santroni, A; Tosi, S; Bailey, S; Brandenburg, G; Morii, M; Won, E; Dubitzky, R S; Langenegger, U; Bhimji, W; Bowerman, D A; Dauncey, P D; Egede, U; Gaillard, J R; Morton, G W; Nash, J A; Taylor, G P; Grenier, G J; Mallik, U; Cochran, J; Crawley, H B; Lamsa, J; Meyer, W T; Prell, S; Rosenberg, E I; Yi, J; Davier, M; Grosdidier, G; Höcker, A; Laplace, S; Le Diberder, F R; Lepeltier, V; Lutz, A M; Petersen, T C; Plaszczynski, S; Schune, M H; Tantot, L; Wormser, G; Cheng, C H; Lange, D J; Simani, M C; Wright, D M; Bevan, A J; Coleman, J P; Fry, J R; Gabathuler, Erwin; Gamet, R; Parry, R J; Payne, D J; Sloane, R J; Touramanis, C; Back, J J; Cormack, C M; Harrison, P F; Mohanty, G B; Brown, C L; Cowan, G; Flack, R L; Flächer, H U; Green, M G; Marker, C E; McMahon, T R; Ricciardi, S; Salvatore, F; Vaitsas, G; Winter, M A; Brown, D; Davis, C L; Allison, J; Barlow, N R; Barlow, R J; Hart, P A; Hodgkinson, M C; Lafferty, G D; Lyon, A J; Williams, J C; Farbin, A; Hulsbergen, W D; Jawahery, A; Kovalskyi, D; Lae, C K; Lillard, V; Roberts, D A; Blaylock, G; Dallapiccola, C; Flood, K T; Hertzbach, S S; Kofler, R; Koptchev, V B; Moore, T B; Saremi, S; Stängle, H; Willocq, S; Cowan, R; Sciolla, G; Taylor, F; Yamamoto, R K; Mangeol, D J J; Patel, P M; Robertson, S H; Lazzaro, A; Palombo, F; Bauer, J M; Cremaldi, L M; Eschenburg, V; Godang, R; Kroeger, R; Reidy, J; Sanders, D A; Summers, D J; Zhao, H W; Brunet, S; Côté, D; Taras, P; Nicholson, H; Cavallo, N; Fabozzi, F; Gatto, C; Lista, L; Monorchio, D; Paolucci, P; Piccolo, D; Sciacca, C; Baak, M; Bulten, H; Raven, G; Wilden, L; Jessop, C P; LoSecco, J M; Gabriel, T A; Allmendinger, T; Brau, B; Gan, K K; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pulliam, T; Rahimi, A M; Ter-Antonian, R; Wong, Q K; Brau, J E; Frey, R; Igonkina, O; Potter, C T; Sinev, N B; Strom, D; Torrence, E; Colecchia, F; Dorigo, A; Galeazzi, F; Margoni, M; Morandin, M; Posocco, M; Rotondo, M; Simonetto, F; Stroili, R; Tiozzo, G; Voci, C; Benayoun, M; Briand, H; Chauveau, J; David, P; La Vaissière, C de; Del Buono, L; Hamon, O; John, M J J; Leruste, P; Ocariz, J; Pivk, M

    2004-01-01

    We present a measurement of the parameters of the $\\Upsilon(10580)$ resonance based on a dataset collected with the BABAR detector at the SLAC PEP-II asymmetric $B$ factory. We measure the total width $\\Gamma_{\\rm tot}$ to be $(20.7\\pm1.6\\pm2.5) {\\rm MeV}$, the electronic partial width $\\Gamma_{ee} = (0.321\\pm0.017\\pm0.029) {\\rm keV}$ and the mass $M = (10579.3\\pm0.4\\pm1.2) {\\rm MeV/c^2}$.

  15. Pulse-width-modulated servo valve for autopilot system

    Science.gov (United States)

    Garner, H. D.

    1974-01-01

    Valve was developed for autopilot wing-lever system and is to be used in light, single-engine aircraft. Valve is controlled by electronic circuit which feeds pulse-width-modulated correction signals to two solenoids. Valve housing is cast from plastic, making it very economical to fabricate.

  16. Dielectron widths of the S-, D-vector bottomonium states

    International Nuclear Information System (INIS)

    The dielectron widths of ?(nS)(n = 1, ..., 7) and vector decay constants are calculated using the relativistic string Hamiltonian with a universal interaction. For ?(nS) (n = 1, 2, 3) the dielectron widths and their ratios are obtained in full agreement with the latest CLEO data. For ?(10580) and ?(11020) a good agreement with experiment is reached only if the 4S-3D mixing (with a mixing angle ? = 27o± 4o) and 6S-5D mixing (with ? = 40o±5o) are taken into account. The possibility to observe higher 'mixed D-wave' resonances, tilde ? (n3D1) with n = 3, 4, 5 is discussed. In particular, tilde ? (?11120), originating from the pure 53D1 state, can acquire a rather large dielectron width, ?130 eV, so that this resonance may become manifest in the e+e- experiments. On the contrary, the widths of pure D-wave states are very small, ?ee(n3D1)? 2 eV.

  17. Widths of the atomic K-N7 levels

    CERN Document Server

    Campbell, J L

    2001-01-01

    Atomic level widths obtained from experimental measurements are collected in Table I, along with the corresponding theoretical widths derived from the Evaluated Atomic Data Library (EADL) of Lawrence Livermore National Laboratory; these EADL values are based upon the Dirac-Hartree-Slater version of the independent-particle model. In a minority of cases, many-body theory predictions are also provided. A brief discussion of the manner in which the experimental widths were deduced from spectroscopic data is included. The bulk of the data are for elements in the solid state, but a few data for gases and simple compounds are included. For the K, L2, L3, and M5 levels, where Coster-Kronig contributions do not contribute or contribute only to a small extent to the overall widths, the EADL predictions appear satisfactory for elements in the solid state. For other levels, where Coster-Kronig and super-Coster-Kronig transitions have large probabilities within the independent-particle model, this model is not satisfacto...

  18. Improved determination of the width of the top quark

    Energy Technology Data Exchange (ETDEWEB)

    Abazov V. M.; Abbott B.; Acharya B. S.; Adams M.; Adams T.; Alexeev G. D.; Alkhazov G.; Alton A.; Alverson G.; Aoki M.; Askew A.; Asman B.; Atkins S.; Atramentov O.; Augsten K.; Avila C.; BackusMayes J.; Badaud F.; Bagby L.; Baldin B.; Bandurin D. V.; Banerjee S.; Barberis E.; Baringer P.; Barreto J.; Bartlett J. F.; Bassler U.; Bazterra V.; Bean A.; Begalli M.; Belanger-Champagne C.; Bellantoni L.; Beri S. B.; Bernardi G.; Bernhard R.; Bertram I.; Besancon M.; Beuselinck R.; Bezzubov V. A.; Bhat P. C.; Bhatia S.; Bhatnagar V.; Blazey G.; Blessing S.; Bloom K.; Boehnlein A.; Boline D.; Boos E. E.; Borissov G.; Bose T.; Brandt A.; Brandt O.; Brock R.; Brooijmans G.; Bross A.; Brown D.; Brown J.; Bu X. B.; Buehler M.; Buescher V.; Bunichev V.; Burdin S.; Burnett T. H.; Buszello C. P.; Calpas B.; Camacho-Perez E.; Carrasco-Lizarraga M. A.; Casey C. K.; Castilla-Valdez H.; Chakrabarti S.; Chakraborty D.; Chan M.; Chandra A.; Chapon E.; Chen G.; Chevalier-Thery S.; Cho D. K.; Cho S. W.; Choi S.; Choudhary B.; Cihangir S.; Claes D.; Clutter J.; Cooke M.; Cooper W. E.; Corcoran M.; Couderc F.; Cousinou M. -C.; Croc A.; Cutts D.; Das A.; Davies G.; de Jong S. J.; De La Cruz-Burelo E.; Deliot F.; Demina R.; Denisov D.; Denisov S. P.; Desai S.; Deterre C.; DeVaughan K.; Diehl H. T.; Diesburg M.; Ding P. F.; Dominguez A.; Dorland T.; Dubey A.; Dudko L. V.; Duggan D.; Duperrin A.; Dutt S.; Dyshkant A.; Eads M.; Edmunds D.; Ellison J.; Elvira V. D.; Enari Y.; Evans H.; Evdokimov A.; Evdokimov V. N.; Facini G.; Ferbel T.; Fiedler F.; Filthaut F.; Fisher W.; Fisk H. E.; Fortner M.; Fox H.; Fuess S.; Garcia-Bellido A.; Garcia-Guerra G. A.; Gavrilov V.; Gay P.; Geng W.; Gerbaudo D.; Gerber C. E.; Gershtein Y.; Ginther G.; Golovanov G.; Goussiou A.; Graf C. P.; Grannis P. D.; Greder S.; Greenlee H.; Greenwood Z. D.; Gregores E. M.; Grenier G.; Gris Ph.; Grivaz J. -F.; Grohsjean A.; Gruenendahl S.; Gruenewald M. W.; Guillemin T.; Gutierrez G.; Gutierrez P.; Haas A.; Hagopian S.; Haley J.; Han L.; Harder K.; Harel A.; Hauptman J. M.; Hays J.; Head T.; Hebbeker T.; Hedin D.; Hegab H.; Heinson A. P.; Heintz U.; Hensel C.; La Cruz I. Heredia-De; Herner K.; Hesketh G.; Hildreth M. D.; Hirosky R.; Hoang T.; Hobbs J. D.; Hoeneisen B.; Hohlfeld M.; Hubacek Z.; Hynek V.; Iashvili I.; Ilchenko Y.; Illingworth R.; Ito A. S.; Jabeen S.; Jaffre M.; Jamin D.; Jayasinghe A.; Jesik R.; Johns K.; Johnson M.; Jonckheere A.; Jonsson P.; Joshi J.; Jung A. W.; Juste A.; Kaadze K.; Kajfasz E.; Karmanov D.; Kasper P. A.; Katsanos I.; Kehoe R.; Kermiche S.; Khalatyan N.; Khanov A.; Kharchilava A.; Kharzheev Y. N.; Kohli J. M.; Kozelov A. V.; Kraus J.; Kulikov S.; Kumar A.; Kupco A.; Kurca T.; Kuzmin V. A.; Lammers S.; Landsberg G.; Lebrun P.; Lee H. S.; Lee S. W.; Lee W. M.; Lellouch J.; Li H.; Li L.; Li Q. Z.; Lietti S. M.; Lim J. K.; Lincoln D.; Linnemann J.; Lipaev V. V.; Lipton R.; Liu Y.; Lobodenko A.; Lokajicek M.; de Sa R. Lopes; Lubatti H. J.; Luna-Garcia R.; Lyon A. L.; Maciel A. K. A.; Mackin D.; Madar R.; Magana-Villalba R.; Malik S.; Malyshev V. L.; Maravin Y.; Martinez-Ortega J.; McCarthy R.; McGivern C. L.; Meijer M. M.; Melnitchouk A.; Menezes D.; Mercadante P. G.; Merkin M.; et al.

    2012-05-04

    We present an improved determination of the total width of the top quark, {Gamma}{sub t}, using 5.4 fb{sup -1} of integrated luminosity collected by the D0 Collaboration at the Tevatron p{bar p} Collider. The total width {Gamma}{sub t} is extracted from the partial decay width {Gamma}(t {yields} Wb) and the branching fraction {Beta}(t {yields} Wb). {Gamma}(t {yields} Wb) is obtained from the t-channel single top-quark production cross section and {Beta}(t {yields} Wb) is measured in t{bar t} events. For a top mass of 172.5 GeV, the resulting width is {Gamma}{sub t} = 2.00{sub -0.43}{sup +0.47} GeV. This translates to a top-quark lifetime of {tau}{sub t} = (3.29{sub -0.63}{sup +0.90}) x 10{sup -25} s. We also extract an improved direct limit on the Cabibbo-Kobayashi-Maskawa quark-mixing matrix element 0.81 < |V{sub tb}| {le} 1 at 95% C.L. and a limit of |V{sub tb}| < 0.59 for a high-mass fourth-generation bottom quark assuming unitarity of the fourth-generation quark-mixing matrix.

  19. Distribution of resonance widths in localized tight-binding models

    Science.gov (United States)

    Terraneo, M.; Guarneri, I.

    2000-11-01

    We numerically analyze the distribution of scattering resonance widths in one- and quasi-one dimensional tight binding models, in the localized regime. We detect and discuss an algebraic decay of the distribution, similar, though not identical, to recent theoretical predictions.

  20. Distribution of resonance widths in localized tight-binding models

    CERN Document Server

    Terraneo, M

    2000-01-01

    We numerically analyze the distribution of scattering resonance widths in one- and quasi-one dimensional tight binding models, in the localized regime. We detect and discuss an algebraic decay of the distribution, similar, though not identical, to recent theoretical predictions.

  1. K emission line widths in the Sun and the stars

    International Nuclear Information System (INIS)

    K emission line widths measured with a micrometer on integrated spectra of the Sun have a mean value of 38.2 km/s. A definition is proposed whereby the width is a measure in km/s at the e-1 value of the difference between the intensity of the brighter K2 peak over the K1 background, reckoned from this latter level. Averaged spectra over different parts of the solar disc show the very appreciable contribution by rotation to the emission line width, making it imperative for any calibration of width with absolute magntiude to use a solar value derived from an integrated spectrum. Arguments are presented showing that the K emission profile observed in other stars is the profile of the typical bright mottle that should enable the derivation of chromospheric parameters. From measures of Doppler displacements of both K2 and K3 'dark condensations' as seen on the Sun are at play in the atmospheres of stars with K emission. (author)

  2. Spreading width of Gamow-Teller resonances in 208Bi

    International Nuclear Information System (INIS)

    The spreading width of the Gamow-Teller resonance in 208Bi is studied in the self-consistent TDA with the Skyrme interaction. Coupling between 1p1h states and 2p2h states are included in the TDA linear response function. (orig.)

  3. Optical line width in quantum dot or nanotransistor.

    Czech Academy of Sciences Publication Activity Database

    Král, Karel; Menšík, Miroslav

    2010-01-01

    Ro?. 8, - (2010), s. 136-140. ISSN 1348-0391 R&D Projects: GA MŠk ME 866; GA ?R GA202/07/0643 Institutional research plan: CEZ:AV0Z10100520; CEZ:AV0Z40500505 Keywords : quantum dot s * line width * optical spectra * nanotransistor Subject RIV: BM - Solid Matter Physics ; Magnetism

  4. Hadron resonances, large Nc, and the half-width rule

    OpenAIRE

    Arriola, Enrique Ruiz; Broniowski, Wojciech; Masjuan, Pere

    2012-01-01

    We suggest using the half-width rule to make an estimate of the 1/Nc errors in hadronic models containing resonances. We show simple consequences ranging from the analysis of meson Regge trajectories, the hadron resonance gas at finite temperature and generalized hadronic form factors.

  5. Sinusoidal and Space Vector Pulse Width Modulation for Inverter

    Directory of Open Access Journals (Sweden)

    K. Mounika#1 , B. Kiran Babu

    2013-04-01

    Full Text Available Inverters inherently have the property of controlling output frequency but the output voltage can’t be varied. Usually to vary output voltage we have to vary supply voltage which is not always possible for this reason PWM techniques gained momentum. Basic aim of PWM technique is to control output voltage and harmonic reduction. Pulse-width modulation (PWM, or pulseduration modulation (PDM, is a commonly used technique for controlling power to inertial electrical devices, made practical by modern electronic power switches. Here we apply PWM techniques like Sinusoidal pulse width modulation (SPWM and Space Vector Pulse width Modulation (SVPWM to inverter and study its performance. In Sinusoidal Pulse width modulation (SPWM we generate the gating signals by comparing a sinusoidal reference signal with a triangular carrier wave. In Space vector Modulation (SVPWM we consider a rotating phased which is obtained by adding all the three voltages. Modulation is accomplished by switching state of an inverter. Thus by comparing these two techniques we study the performance of our inverter.

  6. Overtraining increases the strength of equivalence relations

    Directory of Open Access Journals (Sweden)

    Renato Bortoloti

    2014-07-01

    Full Text Available The present study investigated whether overtraining of the conditional discriminations that are the prerequisites of equivalence class formation strengthens the relations among stimuli in an equivalence class. Two groups of college students formed equivalence classes that consisted of faces that expressed emotions (A and arbitrary stimuli (B, C, D, and E. The overtraining group had twice as many training trials as the regular training group. For participants who formed equivalence classes, relational strength was evaluated by the generalization of expressed emotions from the A to the D stimuli, which was measured using a semantic differential. An untrained control group showed semantic differential scores that were positive for happy faces, negative for angry faces, and neutral for the D stimuli. For the experimental groups, the D stimuli, when included in equivalence classes, produced scores that were similar to those produced by the equivalent faces. The overtraining group, however, had average values closer to the values of the faces than the regular training group. These results indicate that the amount of training is an experimental parameter that influences the strength of relations between stimuli that are found to be equivalent in matching-tosample tests.

  7. Overtraining increases the strength of equivalence relations

    Scientific Electronic Library Online (English)

    Renato, Bortoloti; Naomi Cristina, Rodrigues; Mariéle Diniz, Cortez; Naiene, Pimentel; Julio C. de, Rose.

    2013-12-01

    Full Text Available The present study investigated whether overtraining of the conditional discriminations that are the prerequisites of equivalence class formation strengthens the relations among stimuli in an equivalence class. Two groups of college students formed equivalence classes that consisted of faces that exp [...] ressed emotions (A) and arbitrary stimuli (B, C, D, and E). The overtraining group had twice as many training trials as the regular training group. For participants who formed equivalence classes, relational strength was evaluated by the generalization of expressed emotions from the A to the D stimuli, which was measured using a semantic differential. An untrained control group showed semantic differential scores that were positive for happy faces, negative for angry faces, and neutral for the D stimuli. For the experimental groups, the D stimuli, when included in equivalence classes, produced scores that were similar to those produced by the equivalent faces. The overtraining group, however, had average values closer to the values of the faces than the regular training group. These results indicate that the amount of training is an experimental parameter that influences the strength of relations between stimuli that are found to be equivalent in matching-to-sample tests.

  8. Relating equivalence relations to equivalence relations: A relational framing model of complex human functioning

    OpenAIRE

    Barnes, Dermot; Hegarty, Neil; Smeets, Paul M.

    1997-01-01

    The current study aimed to develop a behavior-analytic model of analogical reasoning. In Experiments 1 and 2 subjects (adults and children) were trained and tested for the formation of four, three-member equivalence relations using a delayed matching-to-sample procedure. All subjects (Experiments 1 and 2) were exposed to tests that examined relations between equivalence and non-equivalence relations. For example, on an equivalence-equivalence relation test, the complex sample B1/C1 and the tw...

  9. FREQUENCY DEPENDENCE OF PULSE WIDTH FOR 150 RADIO NORMAL PULSARS

    Energy Technology Data Exchange (ETDEWEB)

    Chen, J. L. [Department of Physics and Electronic Engineering, Yuncheng University, 044000, Yuncheng, Shanxi (China); Wang, H. G., E-mail: hgwang.gz@gmail.com [Center for Astrophysics, Guangzhou University, 510006, Guangzhou (China)

    2014-11-01

    The frequency dependence of the pulse width is studied for 150 normal pulsars, mostly selected from the European Pulsar Network, for which the 10% multifrequency pulse widths can be well fit with the Thorsett relationship W {sub 10} = A?{sup ?} + W {sub 10,} {sub min}. The relative fraction of pulse width change between 0.4 GHz and 4.85 GHz, ? = (W {sub 4.85} – W {sub 0.4})/W {sub 0.4}, is calculated in terms of the best-fit relationship for each pulsar. It is found that 81 pulsars (54%) have ? < –10% (group A), showing considerable profile narrowing at high frequencies, 40 pulsars (27%) have –10% ?? ? 10% (group B), meaning a marginal change in pulse width, and 29 pulsars (19%) have ? > 10% (group C), showing a remarkable profile broadening at high frequencies. The fractions of the group-A and group-C pulsars suggest that the profile narrowing phenomenon at high frequencies is more common than the profile broadening phenomenon, but a large fraction of the group-B and group-C pulsars (a total of 46%) is also revealed. The group-C pulsars, together with a portion of group-B pulsars with slight pulse broadening, can hardly be explained using the conventional radius-to-frequency mapping, which only applies to the profile narrowing phenomenon. Based on a recent version of the fan beam model, a type of broadband emission model, we propose that the diverse frequency dependence of pulse width is a consequence of different types of distribution of emission spectra across the emission region. The geometrical effect predicting a link between the emission beam shrinkage and spectrum steepening is tested but disfavored.

  10. FREQUENCY DEPENDENCE OF PULSE WIDTH FOR 150 RADIO NORMAL PULSARS

    International Nuclear Information System (INIS)

    The frequency dependence of the pulse width is studied for 150 normal pulsars, mostly selected from the European Pulsar Network, for which the 10% multifrequency pulse widths can be well fit with the Thorsett relationship W 10 = A?? + W 10, min. The relative fraction of pulse width change between 0.4 GHz and 4.85 GHz, ? = (W 4.85 – W 0.4)/W 0.4, is calculated in terms of the best-fit relationship for each pulsar. It is found that 81 pulsars (54%) have ? < –10% (group A), showing considerable profile narrowing at high frequencies, 40 pulsars (27%) have –10% ?? ? 10% (group B), meaning a marginal change in pulse width, and 29 pulsars (19%) have ? > 10% (group C), showing a remarkable profile broadening at high frequencies. The fractions of the group-A and group-C pulsars suggest that the profile narrowing phenomenon at high frequencies is more common than the profile broadening phenomenon, but a large fraction of the group-B and group-C pulsars (a total of 46%) is also revealed. The group-C pulsars, together with a portion of group-B pulsars with slight pulse broadening, can hardly be explained using the conventional radius-to-frequency mapping, which only applies to the profile narrowing phenomenon. Based on a recent version of the fan beam model, a type of broadband emission model, we propose that the diverse frequency dependence of pulse width is a consequence of different types of distribution of emission spectra across the emission region. The geometrical effect predicting a link between the emission beam shrinkage and spectrum steepening is tested but disfavored

  11. On the equivalence of dual theories

    CERN Document Server

    Subbotin, A V

    1995-01-01

    We discuss the equivalence of two dual scalar field theories in 2 dimensions. The models are derived though the elimination of different fields in the same Freedman--Townsend model. It is shown that tree S-matrices of these models do not coincide. The 2-loop counterterms are calculated. It turns out that while one of these models is single-charged, the other theory is multi-charged. Thus the dual models considered are non-equivalent on classical and quantum levels. It indicates the possibility of the anomaly leading to non-equivalence of dual models.

  12. Conformal transformations and the conformal equivalence principle

    CERN Document Server

    Quiros, Israel; Aguilar, Jose Edgar Madriz

    2011-01-01

    It is demonstrated that, unless the meaning of conformal transformations for the underlying geometrical structure is discussed on a same footing as it is done for the relevant equations of the given gravity theory, the notion of "conformal equivalence", as it has been mostly used in the bibliography to date, lacks physical and mathematical content. A principle of conformal equivalence is then formulated and its consequences are investigated within a conformally invariant modification of Brans-Dicke (BD) theory of gravity. It is also demonstrated that standard vacuum BD theory is not conformally invariant and, consequently, the different conformal frames in which the theory can be formulated are neither physically nor mathematically equivalent.

  13. Intensity modulated radiation therapy with multileaf collimators of different leaf widths: a comparison of achievable dose distributions

    International Nuclear Information System (INIS)

    Purpose: A planning study to analyze the impact of different leaf widths on the achievable dose distributions with intensity modulated radiation therapy (IMRT). Methods: Five patients (3 intra- and 2 extra-cranial) with projected planning target volume (PTV) sizes smaller than 10 cm by 10 cm were re-planned with four different multileaf collimators (MLC). Two internal collimators with an isocentric leaf width of 4 and 10 mm and two add-on collimators with an isocentric leaf width of 2.75 and 4 mm were evaluated. The inverse treatment planning system KonRad (Siemens Medical Solutions) was used to create IMRT 'step and shoot' plans. For each patient the same arrangement of beams and the same parameters for the optimization were used for all MLCs. The beamlet size for all treatment plans was chosen to coincide with the leaf width of the respective MLC. To evaluate the treatment plans 3D dose distributions and dose volume histograms were analyzed. As indicators for the quality of the PTV dose distribution the minimum dose, maximum dose and the standard deviation were used. For the organs at risk (OAR) the equivalent uniform dose (EUD) was calculated. To measure the dose coverage of the PTV the volume (V 90) that received doses higher than 90% of the prescribed dose was calculated where for the conformity the dose conformity index given by Baltas et al. was determined. Results: The MLC with the smallest leaf width yields the best mean value of all five patients the best mean value of all five patients for the PTV coverage and for the conformity. For the MLCs with the same leaf width, the add-on MLC leads to superior treatment plans than the internal MLC. This is due to the sharper penumbra of the add-on MLC. The number of IMRT field segments to deliver increased by approximately a factor of two if 2.75 mm MLC leafs are used instead of the standard 10 mm leafs. In case of the para-spinal patients the EUD value for the spinal cord is only reduced slightly by using MLCs with leaf widths smaller than 5 mm. For the intra-cranial the EUD value for some organs improved with reduced leaf widths while for some organs the 10 mm MLC leafs give comparable values. Conclusion: As expected the MLC with the smallest leaf width always yields the best PTV coverage. Reducing the leaf width from 4 to 2.75 mm results in a slight enhancement of the PTV coverage. With the selected organ parameters no significant improvement for most OAR was found. The disadvantage of the reduction of the leaf width is the increasing number of segments due to the more complex fluence patterns and therefore an increased delivery time

  14. Integral equivalence of multidimensional differential systems

    OpenAIRE

    Gorbuzov, V. N.

    2009-01-01

    The bases of the theory of integrals for multidimensional differential systems are stated. The integral equivalence of total differential systems, linear homogeneous systems of partial differential equations, and Pfaff systems of equations is established.

  15. The Field Of Equivalent Some Numeral Methods

    Directory of Open Access Journals (Sweden)

    I. S. Kashirsky

    2008-05-01

    Full Text Available This paper describes some properties of methods for numeral solving partial differential equations. A number of identities are proved to show there are regions of equivalency for finite differences methods and finite elements Ritz-method.

  16. Topological equivalence in families of complex polynomials

    CERN Document Server

    Bodin, A; Bodin, Arnaud; Tibar, Mihai

    2003-01-01

    We show that two polynomials, joined by a continuous family of polynomial functions $f_s \\colon \\mathbb{C}^n \\to \\mathbb{C}$ of constant degree and with isolated singularities, are topologically equivalent if $n\

  17. 7 CFR 1007.54 - Equivalent price.

    Science.gov (United States)

    2010-01-01

    ... true Equivalent price. 1007.54 Section...Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders...MILK IN THE SOUTHEAST MARKETING AREA Order Regulating Handling Class Prices § 1007.54...

  18. 7 CFR 1030.54 - Equivalent price.

    Science.gov (United States)

    2010-01-01

    ... true Equivalent price. 1030.54 Section...Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders...IN THE UPPER MIDWEST MARKETING AREA Order Regulating Handling Class Prices § 1030.54...

  19. 7 CFR 1124.54 - Equivalent price.

    Science.gov (United States)

    2010-01-01

    ... true Equivalent price. 1124.54 Section...Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders...THE PACIFIC NORTHWEST MARKETING AREA Order Regulating Handling Class Prices § 1124.54...

  20. 7 CFR 1005.54 - Equivalent price.

    Science.gov (United States)

    2010-01-01

    ... true Equivalent price. 1005.54 Section...Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders...MILK IN THE APPALACHIAN MARKETING AREA Order Regulating Handling Class Prices § 1005.54...

  1. 7 CFR 1032.54 - Equivalent price.

    Science.gov (United States)

    2010-01-01

    ... true Equivalent price. 1032.54 Section...Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders... MILK IN THE CENTRAL MARKETING AREA Order Regulating Handling Class Prices § 1032.54...

  2. 7 CFR 1131.54 - Equivalent price.

    Science.gov (United States)

    2010-01-01

    ... true Equivalent price. 1131.54 Section...Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders... MILK IN THE ARIZONA MARKETING AREA Order Regulating Handling Class Prices § 1131.54...

  3. 7 CFR 1126.54 - Equivalent price.

    Science.gov (United States)

    2010-01-01

    ... true Equivalent price. 1126.54 Section...Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders...MILK IN THE SOUTHWEST MARKETING AREA Order Regulating Handling Class Prices § 1126.54...

  4. 7 CFR 1001.54 - Equivalent price.

    Science.gov (United States)

    2010-01-01

    ... true Equivalent price. 1001.54 Section...Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders...MILK IN THE NORTHEAST MARKETING AREA Order Regulating Handling Class Prices § 1001.54...

  5. 7 CFR 1033.54 - Equivalent price.

    Science.gov (United States)

    2010-01-01

    ... true Equivalent price. 1033.54 Section...Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders... MILK IN THE MIDEAST MARKETING AREA Order Regulating Handling Class Prices § 1033.54...

  6. 7 CFR 1006.54 - Equivalent price.

    Science.gov (United States)

    2010-01-01

    ... true Equivalent price. 1006.54 Section...Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders... MILK IN THE FLORIDA MARKETING AREA Order Regulating Handling Class Prices § 1006.54...

  7. Equivalence Principle, Higgs Boson and Cosmology

    Directory of Open Access Journals (Sweden)

    Mauro Francaviglia

    2013-05-01

    Full Text Available We discuss here possible tests for Palatini f(R-theories together with their implications for different formulations of the Equivalence Principle. We shall show that Palatini f(R-theories obey the Weak Equivalence Principle and violate the Strong Equivalence Principle. The violations of the Strong Equivalence Principle vanish in vacuum (and purely electromagnetic solutions as well as on short time scales with respect to the age of the universe. However, we suggest that a framework based on Palatini f(R-theories is more general than standard General Relativity (GR and it sheds light on the interpretation of data and results in a way which is more model independent than standard GR itself.

  8. Bisimulations Meet PCTL Equivalences for Probabilistic Automata

    CERN Document Server

    Song, Lei; Godskesen, Jens Chr

    2011-01-01

    Probabilistic automata (PA) have been successfully applied in the formal verification of concurrent and stochastic systems. Efficient model checking algorithms have been studied, where the most often used logics for expressing properties are based on PCTL and its extension PCTL*. Various behavioral equivalences are proposed for PAs, as a powerful tool for abstraction and compositional minimization for PAs. Unfortunately, the behavioral equivalences are well-known to be strictly stronger than the logical equivalences induced by PCTL or PCTL*. This paper introduces novel notions of strong bisimulation relations, which characterizes PCTL and PCTL* exactly. We also extend weak bisimulations characterizing PCTL and PCTL* without next operator, respectively. Thus, our paper bridges the gap between logical and behavioral equivalences in this setting.

  9. Equivalence in Translation Theories: A Critical Evaluation

    Directory of Open Access Journals (Sweden)

    Despoina Panou

    2013-01-01

    Full Text Available The concept of equivalence can be said to hold a central position in translation studies. Nevertheless, it has been a rather controversial one, causing many heated debates among translators as to its nature, definition and applicability. The aim of the present paper is to provide a critical evaluation of the most influential equivalence theories that have been proposed by scholars in the field, such as Vinay and Darbelnet (1958, Jakobson (1959, Nida and Taber (1969, Catford (1965, House (1997, Koller (1979, Newmark (1981, Baker (1992, and finally, Pym (2010. These theories are presented  so as to provide a better understanding of how the concept evolved. It is concluded that the usefulness or not of the concept of equivalence to the translation process varies according to the stance of the translators concerned on what they regard are the virtues of equivalence itself.

  10. Multiresolution weighted norm equivalences and applications

    OpenAIRE

    Beuchler, Sven; Schneider, Reinhold; Schwab, Christoph

    2006-01-01

    We establish multiresolution norm equivalences in weighted spaces L2w((0,1)) with possibly singular weight functions w(x)?0 in (0,1). Our analysis exploits the locality of the biorthogonal wavelet basis and its dual basis functions. The discrete norms are sums of wavelet coefficients which are weighted with respect to the collocated weight function w(x) within each scale. Since norm equivalences for Sobolev norms are by now well-known, our result can...

  11. Equivalent Hermitian operator from supersymmetric quantum mechanics

    International Nuclear Information System (INIS)

    Full text: (author)The metric operator ?, which is the basic ingredient for studying a quantum system described by a pseudo-Hermitian Hamiltonian H, provides the necessary means for obtaining an equivalent description of the system using a Hermitian Hamiltonian h. In the framework of supersymmetric quantum mechanics, we propose a method of constructing the metric operators ? and ?? to obtain the Hermitian Hamiltonians h and h? equivalent to the pseudo-Hermitian H and H+

  12. Quantum Mechanics from an Equivalence Principle

    OpenAIRE

    Faraggi, Alon E.; Matone, Marco

    1997-01-01

    We postulate that physical states are equivalent under coordinate transformations. We then implement this equivalence principle first in the case of one-dimensional stationary systems showing that it leads to the quantum analogue of the Hamilton-Jacobi equation which in turn implies the Schroedinger equation. In this context the Planck constant plays the role of covariantizing parameter. The construction is deeply related to the GL(2,C)-symmetry of the second-order different...

  13. Explicit Homotopy Equivalences Between Some Operads

    CERN Document Server

    Hoefel, Eduardo

    2011-01-01

    In this work we present an explicit operad morphism that is also a homotopy equivalence between the operad given by the real Fulton MacPherson compactification of configuration spaces and the little $n$-disks operad. In particular, the construction gives an operadic homotopy equivalence between the associahedra and the little intervals explicitly. It can also be extended to the case of Kontsevich compactification and Voronov swiss-cheese operad.

  14. Refining the Proof of Planar Equivalence

    CERN Document Server

    Armoni, A; Veneziano, Gabriele

    2005-01-01

    We outline a full non-perturbative proof of planar (large-N) equivalence between bosonic correlators in a theory with Majorana fermions in the adjoint representation and one with Dirac fermions in the two-index (anti)symmetric representation. In a particular case (one flavor), this reduces to our previous result - planar equivalence between super-Yang--Mills theory and a non-supersymmetric ``orientifold field theory.'' The latter theory becomes one-flavor massless QCD at N=3.

  15. The Physical Mirror Equivalence for the Local

    Science.gov (United States)

    Cacciatori, Sergio Luigi; Compagnoni, Marco; Guerra, Stefano

    2015-01-01

    In this paper we consider the total space of the canonical bundle of and we use a proposal by Hosono, together with results of Seidel and Auroux-Katzarkov-Orlov, to deduce the physical mirror equivalence between and the derived Fukaya category of its mirror which assigns the expected central charge to BPS states. By construction, our equivalence is compatible with the mirror map relating the complex and the Kähler moduli spaces and with the computation of Gromov-Witten invariants.

  16. Equivalence Theory Applied to Anisotropic Thin Plates

    OpenAIRE

    Madjid Haddad; Yves Gourinat; Miguel Charlotte

    2011-01-01

    We extend the Equivalence Theory (ET) formulated by Absi [1] for the statics of isotropic materials to the statics and dynamics of orthotropic materials. That theory relies on the assumption that any real body mod- eling may be substituted by another one that, even though it may possibly have material constitutive laws and geometric properties with no physical sense (like negative cross sections or Young modulus), is intended to be more advantageous for calculus. In our approach, the equivale...

  17. Equivalent Scale on Food Consumption in Turkey

    OpenAIRE

    Haydar Sengul

    2006-01-01

    This study investigates effect of household composition and size on food consumption in the rural and urban areas of Turkey through equivalence scales that vary by household member age. Food consumption studies on Turkey have tended to ignore the impact of household composition in consumption traditionally analyses of food consumption are conducted on a per capita basis. Equivalence scales were estimated by Engel method using Household Consumption Expenditure Survey (HCES) data of the State I...

  18. Wilf Equivalence for the Charge Statistic

    OpenAIRE

    Killpatrick, Kendra

    2012-01-01

    Savage and Sagan have recently defined a notion of st-Wilf equivalence for any permutation statistic st and any two sets of permutations $\\Pi$ and $\\Pi'$. In this paper we give a thorough investigation of st-Wilf equivalence for the charge statistic on permutations and use a bijection between the charge statistic and the major index to prove a conjecture of Dokos, Dwyer, Johnson, Sagan and Selsor regarding powers of 2 and the major index.

  19. Equivalence relations and the reinforcement contingency.

    OpenAIRE

    Sidman, M.

    2000-01-01

    Where do equivalence relations come from? One possible answer is that they arise directly from the reinforcement contingency. That is to say, a reinforcement contingency produces two types of outcome: (a) 2-, 3-, 4-, 5-, or n-term units of analysis that are known, respectively, as operant reinforcement, simple discrimination, conditional discrimination, second-order conditional discrimination, and so on; and (b) equivalence relations that consist of ordered pairs of all positive elements that...

  20. Dark matter and the equivalence principle

    Science.gov (United States)

    Frieman, Joshua A.; Gradwohl, Ben-Ami

    1993-01-01

    A survey is presented of the current understanding of dark matter invoked by astrophysical theory and cosmology. Einstein's equivalence principle asserts that local measurements cannot distinguish a system at rest in a gravitational field from one that is in uniform acceleration in empty space. Recent test-methods for the equivalence principle are presently discussed as bases for testing of dark matter scenarios involving the long-range forces between either baryonic or nonbaryonic dark matter and ordinary matter.

  1. On the generation of equivalent hamiltonians

    International Nuclear Information System (INIS)

    A new approach to the equivalence problem (in phase space) is presented. Given a Hamiltonian describing a system of particles with two degrees of freedom (and the corresponding Hamilton-Jacobi equation), it is shown how to find the most general family of Hamiltonian functions that generates new Hamilton-Jacobi equation with the following (and essential) characteristic, here defined as equivalence: every new solution is also a solution of the original Hamilton-Jacobi equation and vice-versa. (Author)

  2. Equivalent circuit model of radiative heat transfer

    OpenAIRE

    Maslovski, Stanislav I.; Simovski, Constantin R.; Tretyakov, Sergei A.

    2012-01-01

    Here, we develop a theory of radiative heat transfer based on an equivalent electrical network representation for the hot material slabs in an arbitrary multilayered environment with arbitrary distribution of temperatures and electromagnetic properties among the layers. Our approach is fully equivalent to the known theories operating with the fluctuating current density, while being significantly simpler in analysis and applications. A practical example of the near-infrared ...

  3. Bisimulations Meet PCTL Equivalences for Probabilistic Automata

    OpenAIRE

    Song, Lei; Zhang, Lijun; Godskesen, Jens Chr.

    2011-01-01

    Probabilistic automata (PA) [20] have been successfully applied in the formal verification of concurrent and stochastic systems. Efficient model checking algorithms have been studied, where the most often used logics for expressing properties are based on PCTL [11] and its extension PCTL? [4]. Various behavioral equivalences are proposed for PAs, as a powerful tool for abstraction and compositional minimization for PAs. Unfortunately, the behavioral equivalences are well-k...

  4. The endotopism semigroups of an equivalence relation

    International Nuclear Information System (INIS)

    In this work we investigate six types of endotopism semigroups for a given equivalence relation. Necessary and sufficient conditions for the existence of all such endotopisms are presented. Conditions for the regularity and coregularity of each of the endotopism semigroups of a given type are established. The notion of the endotype of a binary relation with respect to its endotopisms is introduced and the endotype of an arbitrary equivalence relation is calculated. Bibliography: 26 titles

  5. Fiscal adjustments in Europe and Ricardian equivalence

    OpenAIRE

    Bonis, V.; Paladini, R.

    1998-01-01

    According to the ‘Ricardian’ equivalence hypothesis, consumption is dependent on permanent disposable income and current deficits are equivalent to future tax payments. This hypothesis is tested on 14 European countries in the 1990s. The relationships between private sector savings and general government deficit, and the GDP growth rate and the unemployment rate are determined. The results show the change in consumers' behaviour with respect to government deficit, and that expectations of...

  6. Equivalence in Translation Theories: A Critical Evaluation

    OpenAIRE

    Despoina Panou

    2013-01-01

    The concept of equivalence can be said to hold a central position in translation studies. Nevertheless, it has been a rather controversial one, causing many heated debates among translators as to its nature, definition and applicability. The aim of the present paper is to provide a critical evaluation of the most influential equivalence theories that have been proposed by scholars in the field, such as Vinay and Darbelnet (1958), Jakobson (1959), Nida and Taber (1969), Catford (1965), House (...

  7. The effective theory of Borel equivalence relations

    DEFF Research Database (Denmark)

    Fokina, E.B.; Friedman, S.-D.

    2010-01-01

    The study of Borel equivalence relations under Borel reducibility has developed into an important area of descriptive set theory. The dichotomies of Silver [20] and Harrington, Kechris and Louveau [6] show that with respect to Borel reducibility, any Borel equivalence relation strictly above equality on ? is above equality on P (?), the power set of ?, and any Borel equivalence relation strictly above equality on the reals is above equality modulo finite on P (?). In this article we examine the effective content of these and related results by studying effectively Borel equivalence relations under effectively Borel reducibility. The resulting structure is complex, even for equivalence relations with finitely many equivalence classes. However use of Kleene's O as a parameter is sufficient to restore the picture from the noneffective setting. A key lemma is that of the existence of two effectively Borel sets of reals, neither of which contains the range of the other under any effectively Borel function; the proof of this result applies Barwise compactness to a deep theorem of Harrington (see [5,16]) establishing for any recursive ordinal ? the existence of ? singletons whose ?-jumps are Turing incomparable. © 2009 Elsevier B.V. All rights reserved.

  8. Stark widths and oscillator strengths of Xe III lines

    International Nuclear Information System (INIS)

    In order to test the reliability of the configuration interaction (CI) method to predict the atomic parameters viz oscillator strengths of complex ions, we measured the profiles of forty (40) strong 6s-6p transitions of Xe III emitted by a pulsed capillary discharge. After deconvoluting the experimental shapes, Stark widths and relative oscillator strengths were obtained. When least square fitted (LSF) parameters were used in addition to extensive CI (CI + LSF), the agreement between theory and experiment for the gf's is within a factor two for the whole of the lines. Concerning the widths, the semiempirical approach provides values also within a factor two when the Gaunt factor is taken to be g(x) ? 0.30. (orig.)

  9. Width and finite extinction time of Ricci flow

    CERN Document Server

    Colding, Tobias H

    2007-01-01

    This is an expository article with complete proofs intended for a general non-specialist audience. The results are two-fold. First, we discuss a geometric invariant, that we call the width, of a manifold and show how it can be realized as the sum of areas of minimal 2-spheres. For instance, when $M$ is a homotopy 3-sphere, the width is loosely speaking the area of the smallest 2-sphere needed to ``pull over'' $M$. Second, we use this to conclude that Hamilton's Ricci flow becomes extinct in finite time on any homotopy 3-sphere. We have chosen to write this since the results and ideas given here are quite useful and seem to be of interest to a wide audience.

  10. The excision width in surgical treatment of basal cell carcinoma

    Directory of Open Access Journals (Sweden)

    Mališ M.

    2006-01-01

    Full Text Available Basal cell carcinoma originates from pluripotent cells of basal layer of epiderm, external covering of hair follicles, sebaceous glands or other skin adnexa. It is characterized by local infiltrating and sometimes destructive growth. There are several types of basal cell carcinomas that may be manifested in over 12 clinical forms. Surgical treatment depends to a large extent on the histological type, localization and its clinical manifestation. The analysis included 250 patients of both gender and different age, operated for basal cell carcinoma. Clinical characteristics of basal cell carcinoma and the width of the excision were described. It was concluded that the width of the excision of basal cell cancer was in relation to histological type. .

  11. Dual Amplitude-Width PPM for Free Space Optical Systems

    Directory of Open Access Journals (Sweden)

    Mehdi Rouissat

    2012-04-01

    Full Text Available The PPM (Pulse Position Modulation is commonly used in Free Space Optic (FSO systems owing to its power efficiency, but it shows a rapid decline in spectral efficiency with increase in the power efficiency and moderate data rate. In order to improve these two parameters, we present a modified modulation scheme of the existing PPM, on the basis of PPM, PAM (Pulse Amplitude Modulation and PWM (Pulse Width Modulation. This modified version called DAWPPM (Dual Amplitude-Width PPM.The average power requirements, bandwidth efficiency and normalized data rate are studied after introducing symbol structure. The proposed scheme shows an improvement in terms of data rate and bandwidth efficiency, and when in come to power efficiency it shows lower efficiency compared to PPM. We present theoretical expressions of data rate, spectral efficiency, and normalized power requirements, and we present comparison results to PPM modulation scheme.

  12. Width of Sunspot Generating Zone and Reconstruction of Butterfly Diagram

    CERN Document Server

    Ivanov, V G; 10.1007/s11207-010-9665-6

    2010-01-01

    Based on the extended Greenwich-NOAA/USAF catalogue of sunspot groups it is demonstrated that the parameters describing the latitudinal width of the sunspot generating zone (SGZ) are closely related to the current level of solar activity, and the growth of the activity leads to the expansion of SGZ. The ratio of the sunspot number to the width of SGZ shows saturation at a certain level of the sunspot number, and above this level the increase of the activity takes place mostly due to the expansion of SGZ. It is shown that the mean latitudes of sunspots can be reconstructed from the amplitudes of solar activity. Using the obtained relations and the group sunspot numbers by Hoyt and Schatten (1998), the latitude distribution of sunspot groups ("the Maunder butterfly diagram") for the 18th and the first half of the 19th centuries is reconstructed and compared with historical sunspot observations.

  13. Widths of some L X-ray lines of thorium

    International Nuclear Information System (INIS)

    X-ray L?1, L?2, L?1, L?2, L?3, L?1 line widths of thorium have been measured using a curved crystal spectrometer with a quartz crystal bent to a cylinder of 50 cm radius and a NaI(Tl) scintillation counter. The thorium L X-ray spectra were analysed by means of computational techniques and the experimental results obtained are compared with the theoretical predictions. (orig.)

  14. The modified decay width of the radioactive nucleus

    International Nuclear Information System (INIS)

    It is reported that the width of the first excited state ((7+)/(2),37.133 keV) of 121 51Sb embedded in a ZnSb alloy can be modified by reabsorption of ? -rays scattered backward on the platinum (gold) reflector. Its dependence on the reflector shape is also investigated. The decay rate is reduced about 4.5% at a temperature of 4.2 K by a platinum spherical reflector of 5 mm radius. (orig.)

  15. Perturbative QCD corrections to the Z boson width

    International Nuclear Information System (INIS)

    Radiative QCD corrections significantly influence the theoretical predictions for the decay rates of the Z. The status of the QCD calculations to the hadronic Z width is reviewed. The role of mass corrections from bottom quark final states is emphasized. An estimate of the theoretical uncertainties is given. New results for quartic mass terms of order O(?s2) are presented. The impact of secondary radiation of bottom quarks on the determination of ?(Z?bb) is discussed. ((orig.))

  16. Energy detection UWB system based on pulse width modulation

    OpenAIRE

    Song Cui; Fuqin Xiong

    2014-01-01

    A new energy detection ultra-wideband system based on pulse width modulation is proposed. The bit error rate (BER) performance of this new system is slightly worst than that of a pulse position modulation (PPM) system in additive white Gaussian noise channels. In multipath channels, this system does not suffer from cross-modulation interference as PPM, so it can achieve better BER performance than PPM when cross-modulation interference occurs. In addition, when synchronisation errors occur, t...

  17. Sinusoidal and Space Vector Pulse Width Modulation for Inverter

    OpenAIRE

    K Mounika, B. Kiran Babu

    2013-01-01

    Inverters inherently have the property of controlling output frequency but the output voltage can’t be varied. Usually to vary output voltage we have to vary supply voltage which is not always possible for this reason PWM techniques gained momentum. Basic aim of PWM technique is to control output voltage and harmonic reduction. Pulse-width modulation (PWM), or pulseduration modulation (PDM), is a commonly used technique for controlling power to inertial electrical devices, made practical by...

  18. Temperature dependence of spreading width of giant dipole resonance

    International Nuclear Information System (INIS)

    The Quasiparticle-Phonon Nuclear Model extended to finite temperature within the framework of Thermo Field Dynamics is applied to calculate a temperature dependence of the spreading width ?? of a giant dipole resonance. Numerical calculations are made for 120Sn and 208Pb nuclei. It is found that ?? increases with T. The reason of this effect is discussed as well as a relation of the present approach to other ones, existing in the literature

  19. Neutron Resonance Widths and the Porter-Thomas Distribution

    CERN Document Server

    Volya, Alexander; Zelevinsky, Vladimir

    2015-01-01

    Experimental evidence has recently put the validity of the Porter-Thomas distribution (PTD) for partial neutron widths into question. We identify two terms in the effective Hamiltonian that violate orthogonal invariance (the basis for the PTD). Both are due to the coupling to the decay channels. We show that realistic estimates for the coupling to the neutron channel and for non-statistical gamma decays yield significant modifications of the PTD.

  20. Support functions and mean width for {\\alpha}-concave functions

    OpenAIRE

    Rotem, Liran

    2012-01-01

    In this paper we extend some notions, previously defined for log-concave functions, to the larger domain of so-called {\\alpha}-concave functions. We begin with a detailed discussion of support functions - first for log-concave functions, and then for general {\\alpha}-concave functions. We continue by defining mean width, and proving some basic results such as an Urysohn type inequality. Finally, we demonstrate how such geometric results can imply Poincar\\'e type inequalities.

  1. Porous Alumina Films with Width-Controllable Alumina Stripes

    OpenAIRE

    Huang Shi-Ming; Pu Lin; Shi Yi; Huang Kai; Wu Zhi-Ming; Ji Li; Kang Jun-Yong

    2010-01-01

    Abstract Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure o...

  2. Porous Alumina Films with Width-Controllable Alumina Stripes

    Directory of Open Access Journals (Sweden)

    Huang Shi-Ming

    2010-01-01

    Full Text Available Abstract Porous alumina films had been fabricated by anodizing from aluminum films after an electropolishing procedure. Alumina stripes without pores can be distinguished on the surface of the porous alumina films. The width of the alumina stripes increases proportionally with the anodizing voltage. And the pores tend to be initiated close to the alumina stripes. These phenomena can be ascribed to the electric field distribution in the alumina barrier layer caused by the geometric structure of the aluminum surface.

  3. The Width of Galton- Watson Trees Conditioned by the Size

    OpenAIRE

    Michael Drmota; Bernhard Gittenberger

    2004-01-01

    It is proved that the moments of the width of Galton-Watson trees of size n and with offspring variance ? 2 are asymptotically given by (?? n) p m p where m p are the moments of the maximum of the local time of a standard scaled Brownian excursion. This is done by combining a weak limit theorem and a tightness estimate. The method is quite general and we state some further applications.

  4. Total Width of 125 GeV Higgs Boson

    OpenAIRE

    Barger, Vernon(Department of Physics, University of Wisconsin, Madison, WI, 53706, USA); Ishida, Muneyuki; Keung, Wai-Yee

    2012-01-01

    By using the LHC and Tevatron measurements of the cross sections to various decay channels relative to the standard model Higgs boson, the total width of the putative 125 GeV Higgs boson is determined as 6.1 +7.7-2.9 MeV. We describe a way to estimate the branching fraction for Higgs decay to dark matter. We also discuss a No-Go theorem for the gammagamma signal of the Higgs boson at the LHC.

  5. Beam Width Robustness of a 670 GHz Imaging Radar

    Science.gov (United States)

    Cooper, K. B.; Llombart, N.; Dengler, R. J.; Siegel, P. H.

    2009-01-01

    Detection of a replica bomb belt concealed on a mannequin at 4 m standoff range is achieved using a 670 GHz imaging radar. At a somewhat larger standoff range of 4.6 m, the radar's beam width increases substantially, but the through-shirt image quality remains good. This suggests that a relatively modest increase in aperture size over the current design will be sufficient to detect person-borne concealed weapons at ranges exceeding 25 meters.

  6. Characterization of the optical line width in individual quantum dots.

    Czech Academy of Sciences Publication Activity Database

    Král, Karel; Menšík, Miroslav

    2010-01-01

    Ro?. 7, ?. 3 (2010), s. 73-78. ISSN 1708-5284 R&D Projects: GA MŠk ME 866; GA ?R GA202/07/0643 Institutional research plan: CEZ:AV0Z10100520; CEZ:AV0Z40500505 Keywords : quantum dot s * line width * optical spectra Subject RIV: BM - Solid Matter Physics ; Magnetism http://wjoe.hebeu.edu.cn/2010.3/12.pdf

  7. Measuring crack width and spacing in reinforced concrete members

    OpenAIRE

    Alam, Syed Yasir; Lenormand, Thibault; Loukili, Ahmed; Regoin, J.P.

    2010-01-01

    Cracking behavior of reinforced concrete is usually understood by the cracking of a concrete prism reinforced with a central bar subjected to tension. Bending, which is majority of the real cases, is dealt in the Eurocode by an empirical adjustment of the coefficients. In this paper an experimental program is devised to study the structural size effect of reinforced concrete members on crack width and spacing. Bending tests are performed on three different sizes of beams which are geometrical...

  8. Equivalence of the categories of modules over Lie algebroids

    OpenAIRE

    Hirota, Yuji

    2013-01-01

    We study geometric representation theory of Lie algebroids. A new equivalence relation for integrable Lie algebroids is introduced and investigated. It is shown that two equivalent Lie algebroids have equivalent categories of infinitesimal actions of Lie algebroids. As an application, it is also shown that the Hamiltonian categories for gauge equivalent Dirac structures are equivalent as categories.

  9. Two-pion decay widths of excited charm mesons

    International Nuclear Information System (INIS)

    The widths for ?? decay of the L=1 charm mesons are calculated by describing the pion coupling to light constituents quarks by the lowest-order chiral interaction. The wavefunctions of the charm mesons are obtained as solutions to the covariant Blankenbecler-Sugar equation. These solutions correspond to an interaction Hamiltonian modeled as the sum of a linear scalar confining and a screened one-gluon exchange (OGE) interaction. This interaction induces a two-quark contribution to the amplitude for two-pion decay, which is found to interfere destructively with the single-quark amplitude. For the currently known L=1 D mesons, the total ??-decay widths are found to be ?1 MeV for the D1(2420) and ?3 MeV for the D*2(2460) if the axial coupling of the constituent quark is taken to be gAq=1. The as yet undiscovered spin-singlet D1* state is predicted to have a larger width of 7-10 MeV for ?? decay

  10. The width of gamma-ray burst spectra

    Science.gov (United States)

    Axelsson, Magnus; Borgonovo, Luis

    2015-03-01

    The emission processes active in the highly relativistic jets of gamma-ray bursts (GRBs) remain unknown. In this paper, we propose a new measure to describe spectra: the width of the EFE spectrum, a quantity dependent only on finding a good fit to the data. We apply this to the full sample of GRBs observed by Fermi/Gamma-ray Burst Monitor (GBM) and Compton Gamma-ray Observatory/Burst and Transient Source Experiment (BATSE). The results from the two instruments are fully consistent. We find that the median widths of spectra from long and short GRBs are significantly different (chance probability radiation - the results indicate that a large fraction of GRB spectra are too narrow to be explained by synchrotron radiation from a distribution of electron energies: for example, 78 per cent of long GRBs and 85 per cent of short GRBs are incompatible with the minimum width of standard slow cooling synchrotron emission from a Maxwellian distribution of electrons, with fast cooling spectra predicting even wider spectra. Photospheric emission can explain the spectra if mechanisms are invoked to give a spectrum much broader than a blackbody.

  11. The ?? cloud contribution to the ? width in nuclear matter

    International Nuclear Information System (INIS)

    The width of the ? meson in cold nuclear matter is computed in a hadronic many-body approach, focusing on a detailed treatment of the medium modifications of intermediate ?? states. The ? and ? propagators are dressed by their self-energies in nuclear matter taken from previously constrained many-body calculations. The pion self-energy includes Nh and ?h excitations with short-range correlations, while the ? self-energy incorporates the same dressing of its 2? cloud with a full 3-momentum dependence and vertex corrections, as well as direct resonance-hole excitations; both contributions were quantitatively fit to total photo-absorption spectra and ?N??N scattering. Our calculations account for in-medium decays of type ?N??N(?),??N(?), and 2-body absorptions ?NN?NN(?),?NN. This causes deviations of the in-medium ? width from a linear behavior in density, with important contributions from spacelike ? propagators. The ? width from the ?? cloud may reach up to 200 MeV at normal nuclear matter density, with a moderate 3-momentum dependence. This largely resolves the discrepancy of linear T–? approximations with the values deduced from nuclear photoproduction measurements

  12. Measurement of the mass and width of the W boson

    CERN Document Server

    Abbiendi, G; Åkesson, P F; Alexander, G; Allison, J; Amaral, P; Anagnostou, G; Anderson, K J; Asai, S; Axen, D A; Bailey, I; Barberio, E; Barillari, T; Barlow, R J; Batley, J Richard; Bechtle, P; Behnke, T; Bell, K W; Bell, P J; Bella, G; Bellerive, A; Benelli, G; Bethke, Siegfried; Biebel, O; Boeriu, O; Bock, P; Boutemeur, M; Braibant, S; Brown, R M; Burckhart, H J; Campana, S; Carnegie, R K; Carter, A A; Carter, J R; Chang, C Y; Charlton, D G; Ciocca, C; Csilling, A; Cuffiani, M; Dado, S; de Roeck, A; De Wolf, E A; Desch, Klaus; Dienes, B; Donkers, M; Dubbert, J; Duchovni, E; Duckeck, G; Duerdoth, I P; Etzion, E; Fabbri, Franco Luigi; Fanfani, A; Ferrari, P; Fiedler, F; Fleck, I; Ford, M; Frey, A; Gagnon, P; Gary, J W; Geich-Gimbel, C; Giacomelli, G; Giacomelli, P; Giunta, M; Goldberg, J; Gross, E; Grunhaus, Jacob; Gruwé, M; Günther, P O; Sen-Gupta, A; Hajdu, C; Hamann, M; Hanson, G G; Harel, A; Hauschild, M; Hawkes, C M; Hawkings, R; Hemingway, R J; Herten, G; Heuer, R D; Hill, J C; Hoffman, K; Horváth, D; Igo-Kemenes, P; Ishii, K; Jeremie, H; Jovanovic, P; Junk, T R; Kanzaki, J; Karlen, Dean A; Kawagoe, K; Kawamoto, T; Keeler, R K; Kellogg, R G; Kennedy, B W; Kluth, S; Kobayashi, T; Kobel, M; Komamiya, S; Kramer, T; Krieger, P; Von Krogh, J; Kühl, T; Kupper, M; Lafferty, G D; Landsman, Hagar Yaël; Lanske, D; Lellouch, D; Letts, J; Levinson, L; Lillich, J; Lloyd, S L; Loebinger, F K; Lü, J; Ludwig, A; Ludwig, J; Mader, W; Marcellini, S; Martin, A J; Masetti, G; Mashimo, T; Mättig, P; McKenna, J A; McPherson, R A; Meijers, F; Menges, W; Merritt, F S; Mes, H; Meyer, N; Michelini, A; Mihara, S; Mikenberg, G; Miller, D J; Mohr, W; Montanari, A; Mori, T; Mutter, A; Nagai, K; Nakamura, I; Nanjo, H; Neal, H A; Nisius, R; O'Neale, S W; Oh, A; Oreglia, M J; Orito, S; Pahl, C; Pásztor, G; Pater, J R; Pilcher, J E; Pinfold, J L; Plane, D E; Pooth, O; Przybycien, M B; Quadt, A; Rabbertz, K; Rembser, C; Renkel, P; Roney, J M; Rozen, Y; Runge, K; Sachs, K; Saeki, T; Sarkisyan-Grinbaum, E; Schaile, A D; Schaile, O; Scharff-Hansen, P; Schieck, J; Schörner-Sadenius, T; Schröder, M; Schumacher, M; Seuster, R; Shears, T G; Shen, B C; Sherwood, P; Skuja, A; Smith, A M; Sobie, R J; Söldner-Rembold, S; Spanó, F; Stahl, A; Strom, D; Ströhmer, R; Tarem, S; Tasevsky, M; Teuscher, R; Thomson, M A; Torrence, E; Toya, D; Tran, P; Trigger, I; Trócsányi, Z L; Tsur, E; Turner-Watson, M F; Ueda, I; Ujvári, B; Vollmer, C F; Vannerem, P; Vertesi, R; Verzocchi, M; Voss, H; Vossebeld, Joost Herman; Ward, C P; Ward, D R; Watkins, P M; Watson, A T; Watson, N K; Wells, P S; Wengler, T; Wermes, N; Wilson, G W; Wilson, J A; Wolf, G; Wyatt, T R; Yamashita, S; Zer-Zion, D; Zivkovic, L

    2006-01-01

    The mass and width of the W boson are measured using e+e- -> W+W- events from the data sample collected by the OPAL experiment at LEP at centre-of-mass energies between 170 GeV and 209 GeV. The mass (mw) and width (gw) are determined using direct reconstruction of the kinematics of W+W- -> qqbarlv and W+W- -> qqbarqqbar events. When combined with previous OPAL measurements using W+W- -> lvlv events and the dependence on mw of the WW production cross-section at threshold, the results are determined to be mw = 80.415 +- 0.042 +- 0.030 +- 0.009 GeV gw = 1.996 +- 0.096 +- 0.102 +- 0.003 GeV where the first error is statistical, the second systematic and the third due to uncertainties in the value of the LEP beam energy. By measuring mw with several different jet algorithms in the qqbarqqbar channel, a limit is also obtained on possible final-state interactions due to colour reconnection effects in W+W- -> qqbarqqbar events. The consistency of the results for the W mass and width with those inferred from other ele...

  13. The width of the {omega} meson in the nuclear medium

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, A. [Universitat de Barcelona, Departament d' Estructura i Constituents de la Materia and Institut de Ciencies del Cosmos, Barcelona (Spain); Tolos, L. [Facultat de Ciencies, Instituto de Ciencias del Espacio (IEEC/CSIC) Campus Universitat Autonoma de Barcelona, Barcelona (Spain); Johann Wolfgang Goethe University, Frankfurt Institute for Advanced Studies (FIAS), Frankfurt am Main (Germany); Molina, R. [Research Center for Nuclear Physics (RCNP), Ibaraki (Japan); Oset, E. [Centro Mixto Universidad de Valencia-CSIC, Institutos de Investigacion de Paterna, Departamento de Fisica Teorica and IFIC, Aptdo. 22085, Valencia (Spain)

    2013-11-15

    We evaluate the width of the {omega} meson in nuclear matter. We consider the free decay mode of the {omega} into three pions, which is dominated by {rho}{pi} decay, and replace the {rho} and {pi} propagators by their medium-modified ones. We also take into account the quasielastic and inelastic processes induced by a vector-baryon interaction dominated by vector meson exchange, as well as the contributions coming from the {omega}{yields}K anti K mechanism with medium-modified K, anti K propagators. We obtain a substantial increase of the {omega} width in the medium, reaching a value of 121 {+-} 10 MeV at normal nuclear matter density for an {omega} at rest, which comes mainly from {omega}N {yields} {pi}{pi}N, {omega}NN {yields} {pi}NN processes associated to the dominant {omega} {yields} {rho}{pi} decay mode. The value of the width increases moderately with momentum, reaching values of around 200MeV at 600MeV/c. (orig.)

  14. Analysis Of The Effect Of Flow Channel Width On The Performance Of PEMFC

    Directory of Open Access Journals (Sweden)

    Elif Eker

    2013-08-01

    Full Text Available In this work, it was analysed the effect of different channel width on performance of PEM fuel cell. Current density were measured on the single cells of parallel flow fields that has 25 cm² active layer, using three different kinds of channel width. The cell width and the channel height remain constant.The results show that increasing the channel width while the cell width remains constant decreases the current density.

  15. Equivalent diffusion coefficient and equivalent diffusion accessible porosity of a stratified porous medium

    OpenAIRE

    Huysmans, Marijke; Dassargues, Alain

    2007-01-01

    Diffusion is an important transport process in low permeability media, which play an important role in contamination and remediation of natural environments. The calculation of equivalent diffusion parameters has however not been extensively explored. In this paper, expressions of the equivalent diffusion coefficient and the equivalent diffusion accessible porosity normal to the layering in a layered porous medium are derived based on analytical solutions of the diffusion equation. The expres...

  16. Comparing Fixed and Variable-Width Gaussian Networks.

    Czech Academy of Sciences Publication Activity Database

    K?rková, V?ra; Kainen, P.C.

    2014-01-01

    Ro?. 57, September (2014), s. 23-28. ISSN 0893-6080 R&D Projects: GA MŠk(CZ) LD13002 Institutional support: RVO:67985807 Keywords : Gaussian radial and kernel networks * Functionally equivalent networks * Universal approximators * Stabilizers defined by Gaussian kernels * Argminima of error functionals Subject RIV: IN - Informatics, Computer Science Impact factor: 2.076, year: 2013

  17. Measurements of the Mass, Total Width and Two-Photon Partial Width of the $\\eta_{c}$ Meson

    CERN Document Server

    Brandenburg, G; Gao, Y S; Kim, D Y J; Wilson, R; Browder, T E; Li, Y; Rodríguez, J L; Yamamoto, H; Bergfeld, T; Eisenstein, B I; Ernst, J; Gladding, G E; Gollin, G D; Hans, R M; Johnson, E; Karliner, I; Marsh, M A; Palmer, M; Plager, C; Sedlack, C; Selen, M; Thaler, J J; Williams, J; Edwards, K W; Janicek, R; Patel, P M; Sadoff, A J; Ammar, R; Bean, A; Besson, D; Davis, R; Kwak, N; Zhao, X; Anderson, S; Frolov, V V; Kubota, Y; Lee, S J; Mahapatra, R; O'Neill, J J; Poling, R A; Riehle, T; Smith, A; Stepaniak, C J; Urheim, J; Ahmed, S; Alam, M S; Athar, S B; Jian, L; Ling, L; Saleem, M; Timm, S; Wappler, F; Anastassov, A; Duboscq, J E; Eckhart, E; Gan, K K; Gwon, C; Hart, T; Honscheid, K; Hufnagel, D; Kagan, H; Kass, R; Pedlar, T K; Schwarthoff, H; Thayer, J B; Von Törne, E; Zoeller, M M; Richichi, S J; Severini, H; Skubic, P L; Undrus, A; Chen, S; Fast, J; Hinson, J W; Lee, J; Miller, D H; Shibata, E I; Shipsey, I P J; Pavlunin, V; Cronin-Hennessy, D; Lyon, A L; Thorndike, E H; Jessop, C P; Marsiske, H; Perl, Martin Lewis; Savinov, V; Ugolini, D W; Zhou, X; Coan, T E; Fadeev, V; Maravin, Y; Narsky, I; Stroynowski, R; Ye, J; Wlodek, T; Artuso, M; Ayad, R; Boulahouache, C; Bukin, K; Dambasuren, E; Karamov, S; Majumder, G; Moneti, G C; Mountain, R; Schuh, S; Skwarnicki, T; Stone, S; Viehhauser, G; Wang, J C; Wolf, A; Wu, J; Kopp, S E; Mahmood, A H; Csorna, S E; Danko, I; McLean, K W; Marka, S; Xu, Z; Godang, R; Kinoshita, K; Lai, I C; Schrenk, S; Bonvicini, G; Cinabro, D; McGee, S; Perera, L P; Zhou, G J; Lipeles, E; Pappas, S P; Schmidtler, M; Shapiro, A; Sun, W M; Weinstein, A J; Würthwein, F; Jaffe, D E; Masek, G E; Paar, H P; Potter, E M; Prell, S; Sharma, V; Asner, D M; Eppich, A; Hill, T S; Morrison, R J; Briere, R A; Ferguson, T; Vogel, H; Behrens, B H; Ford, W T; Gritsan, A; Roy, J D; Smith, J G; Alexander, J P; Baker, R; Bebek, C; Berger, B E; Berkelman, K; Blanc, F; Boisvert, V; Cassel, David G; Dickson, M; Drell, P S; Ecklund, K M; Ehrlich, R; Foland, A D; Gaidarev, P B; Galik, R S; Gibbons, L K; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Hopman, P I; Jones, C D; Kreinick, D L; Lohner, M; Magerkurth, A; Meyer, T O; Mistry, N B; Nordberg, E; Patterson, J R; Peterson, D; Riley, D; Thayer, J G; Thies, P G; Urner, D; Valant-Spaight, B L; Warburton, A; Avery, P; Prescott, C; Rubiera, A I; Yelton, J; Zheng, J

    2000-01-01

    Using 13.4 $fb^{-1}$ of data collected with the CLEO detector at the Cornell Electron Storage Ring, we have observed 300 events for the two-photon production of ground-state pseudo-scalar charmonium in the decay $\\eta_c$ -> $K_S K^{\\mp} \\pi^{\\pm}$. We have measured the $\\eta_c$ mass to be (2980.4 +- 2.3 (stat) +- 0.6 (sys)) MeV and its full width as (27.0 +- 5.8 (stat) +- 1.4 (sys)) MeV. We have determined the two-photon partial width of the $\\eta_c$ meson to be (7.6 +- 0.8 (stat) +- 0.4 (sys) +- 2.3 (br)) keV, with the last uncertainty associated with the decay branching fraction.

  18. What Shape is a Landslide? Statistical Patterns in Landslide Length to Width Ratio

    Science.gov (United States)

    Taylor, Faith E.; Malamud, Bruce D.; Witt, Annette

    2015-04-01

    We present a variety of methods to approximate landslide shapes by ellipses, to test the goodness of fit of an elliptical approximation to each landslide shape and to examine the probability distribution of the length-to-width ratio (L/W) of the corresponding ellipses in two substantially complete landslide inventories. The planimetric shape of an individual landslide area is controlled by factors such as terrain morphology, material involved and speed, with landslide shapes varying in total area (AL), type of shape, and their length-to-width ratios. Here, we use mapped polygons from two substantially complete inventories: (i) 11,111 landslides triggered by the 1994 (M = 6.7) Northridge Earthquake, USA (ii) 9,594 landslides triggered by heavy rain during the 1998 Hurricane Mitch in Guatemala. For each landslide polygon, various methods of approximating an elliptical shape were tested. The best method found was fitting a convex hull (CH) to each landslide polygon, approximating an ellipse with equivalent area (ACH) and Perimeter (PCH) of the convex hull and then scaling this ellipse to match the area of the original landslide (AL). The goodness-of-fit (e) of elliptical approximations was tested using a measure of the area of intersection (AI) between the original landslide polygon area (AL) and the elliptical approximation: e = 1 - (2(AL - AI)/AL) =-1+2 AI/AL. The goodness-of-fit e ranges from -1 for an imperfect fit and +1 for a perfect fit. We found that the percentage of landslides having a 'good fit' (e ? 0.5) of the ellipse to the inventory landslide polygons were 99% of landslides from the Northridge inventory and 84% of landslides from the Guatemala inventory. For these landslides, the non-dimensional value of the ratio of the ellipse length-to-width (L/W) was calculated. For the Guatemala landslides, 50 % of landslide ellipse L/W values are ? 2.17, and 90 % of values are ? 3.6. For the Northridge landslides, 50 % of landslide ellipse L/W values are ? 2.5, and 90 % of values are ? 4.4. We find that the probability of the length-to width ratio (L/W) follows a three-parameter inverse gamma distribution, which has an inverse power-law decay for medium and large L/W values (values of L/W > ~2) and exponential rollover for small L/W values. The 'rollover' value where p(L/W) is at its maximum occurs at L/W = 2.1 and L/W = 1.8 for Northridge and Guatemala respectively. There is generally good agreement between the two inventories' statistical distributions in spite of differences in location, triggering mechanism and geology. This work will aid in stochastic modelling of triggered landslide event inventories where it may not be feasible to deterministically define each landside shape. Using these trends, landslide shape can be approximated as an ellipse, and the length to width ratio of that ellipse selected from a general statistical distribution.

  19. Analytic equivalence relations and bi-embedability

    CERN Document Server

    Friedman, Sy-David

    2011-01-01

    Louveau and Rosendal [5] have shown that the relation of bi-embeddability for countable graphs as well as for many other natural classes of countable structures is complete under Borel reducibility for analytic equivalence relations. This is in strong contrast to the case of the isomorphism relation, which as an equivalence relation on graphs (or on any class of countable structures consisting of the models of a sentence of L_{\\omega_1 \\omega}) is far from complete (see [5, 2]). In this article we strengthen the results of [5] by showing that not only does bi-embeddability give rise to analytic equivalence relations which are complete under Borel reducibility, but in fact any analytic equivalence relation is Borel equivalent to such a relation. This result and the techniques introduced answer questions raised in [5] about the comparison between isomorphism and bi-embeddability. Finally, as in [5] our results apply not only to classes of countable structures defined by sentences of L_{\\omega_1 \\omega}, but als...

  20. Ideals and Formal Morita Equivalence of Algebras

    CERN Document Server

    Bursztyn, H; Bursztyn, Henrique; Waldmann, Stefan

    2000-01-01

    Motivated by deformation quantization, we introduced in an earlier work the notion of formal Morita equivalence in the category of $^*$-algebras over a ring $\\ring C$ which is the quadratic extension by $\\im$ of an ordered ring $\\ring R$. The goal of the present paper is twofold. First, we clarify the relationship between formal Morita equivalence, Ara's notion of Morita $^*$-equivalence of rings with involution, and strong Morita equivalence of $C^*$-algebras. Second, in the general setting of $^*$-algebras over $\\ring C$, we define `closed' $^*$-ideals as the ones occuring as kernels of $^*$-representations of these algebras on pre-Hilbert spaces. These ideals form a lattice which we show is invariant under formal Morita equivalence. This result, when applied to Pedersen ideals of $C^*$-algebras, recovers the so-called Rieffel correspondence theorem. The triviality of the minimal element in the lattice of closed ideals, called the `minimal ideal', is also a formal Morita invariant and this fact can be used ...

  1. Nondeterministic automata: equivalence, bisimulations, and uniform relations

    CERN Document Server

    ?iri?, Miroslav; Baši?, Milan; Jan?i?, Ivana

    2011-01-01

    In this paper we study the equivalence of nondeterministic automata pairing the concept of a bisimulation with the recently introduced concept of a uniform relation. In this symbiosis, uniform relations serve as equivalence relations which relate states of two possibly different nondeterministic automata, and bisimulations ensure compatibility with the transitions, initial and terminal states of these automata. We define six types of bisimulations, but due to the duality we discuss three of them: forward, backward-forward, and weak forward bisimulations. For each od these three types of bisimulations we provide a procedure which decides whether there is a bisimulation of this type between two automata, and when it exists, the same procedure computes the greatest one. We also show that there is a uniform forward bisimulation between two automata if and only if the factor automata with respect to the greatest forward bisimulation equivalences on these automata are isomorphic. We prove a similar theorem for weak...

  2. Quantum formulation of the Einstein Equivalence Principle

    CERN Document Server

    Zych, Magdalena

    2015-01-01

    Validity of just a few physical conditions comprising the Einstein Equivalence Principle (EEP) suffices to ensure that gravity can be understood as space-time geometry. EEP is therefore subject to an ongoing experimental verification, with present day tests reaching the regime where quantum mechanics becomes relevant. Here we show that the classical formulation of the EEP does not apply in such a regime. The EEP requires equivalence between the total rest mass-energy of a system, the mass-energy that constitutes its inertia, and the mass-energy that constitutes its weight. In quantum mechanics internal energy is given by a Hamiltonian operator describing dynamics of internal degrees of freedom. We therefore introduce a quantum formulation of the EEP -- equivalence between the rest, inertial and gravitational internal energy operators. We show that the validity of the classical EEP does not imply the validity of its quantum formulation, which thus requires an independent experimental verification. We reanalyse...

  3. System Equivalent for Real Time Digital Simulator

    Science.gov (United States)

    Lin, Xi

    2011-07-01

    The purpose of this research is to develop a method of making system equivalents for the Real Time Digital Simulator (RTDS), which should enhance its capability of simulating large power systems. The proposed equivalent combines a Frequency Dependent Network Equivalent (FDNE) for the high frequency electromagnetic transients and a Transient Stability Analysis (TSA) type simulation block for the electromechanical transients. The frequency dependent characteristic for FDNE is obtained by curve-fitting frequency domain admittance characteristics using the Vector Fitting method. An approach for approximating the frequency dependent characteristic of large power networks from readily available typical power-flow data is also introduced. A new scheme of incorporating TSA solution in RTDS is proposed. This report shows how the TSA algorithm can be adapted to a real time platform. The validity of this method is confirmed with examples, including the study of a multi in-feed HVDC system based network.

  4. Bisimulations Meet PCTL Equivalences for Probabilistic Automata

    DEFF Research Database (Denmark)

    Song, Lei; Zhang, Lijun

    2011-01-01

    Probabilistic automata (PA) have beensuccessfully applied in the formal verification of concurrent andstochastic systems. Efficient model checking algorithms have beenstudied, where the most often used logics for expressing propertiesare based on PCTL and its extensionPCTL*. Variousbehavioral equivalences are proposed for PAs, asa powerful tool for abstraction and compositional minimization forPAs. Unfortunately, the behavioral equivalencesare well-known to be strictly stronger than the logical equivalences inducedby PCTL or PCTL*. This paper introduces novel notions of strongbisimulation relations, which characterizes PCTL and PCTL*exactly. We also extend weak bisimulations characterizingPCTL and PCTL* without next operator, respectively. Thus, ourpaper bridges the gap between logical and behavioral equivalences inthis setting.

  5. Fiscal adjustments in Europe and Ricardian equivalence

    Directory of Open Access Journals (Sweden)

    V. DE BONIS

    1998-09-01

    Full Text Available According to the ‘Ricardian’ equivalence hypothesis, consumption is dependent on permanent disposable income and current deficits are equivalent to future tax payments. This hypothesis is tested on 14 European countries in the 1990s. The relationships between private sector savings and general government deficit, and the GDP growth rate and the unemployment rate are determined. The results show the change in consumers' behaviour with respect to government deficit, and that expectations of an increase in future wealth are no longer associated with a decrease in deficit.

  6. On the Equivalence of Dual Theories

    OpenAIRE

    Subbotin, A.; Tyutin, I. V.

    1995-01-01

    We discuss the equivalence of two dual scalar field theories in 2 dimensions. The models are derived though the elimination of different fields in the same Freedman--Townsend model. It is shown that tree $S$-matrices of these models do not coincide. The 2-loop counterterms are calculated. It turns out that while one of these models is single-charged, the other theory is multi-charged. Thus the dual models considered are non-equivalent on classical and quantum levels. It indi...

  7. Equivalent crossed products and cross product bialgebras

    CERN Document Server

    Panaite, Florin

    2012-01-01

    In a previous paper we proved a result of the type "invariance under twisting" for Brzezinski's crossed products. In this paper we prove a converse of this result, obtaining thus a characterization of what we call equivalent crossed products. As an application, we characterize cross product bialgebras (in the sense of Bespalov and Drabant) that are equivalent (in a certain sense) to a given cross product bialgebra in which one of the factors is a bialgebra and whose coalgebra structure is a tensor product coalgebra.

  8. Poisson Equivalence over a Symplectic Leaf

    CERN Document Server

    Vorobjev, Y

    2005-01-01

    We study the equivalence of Poisson structures around a given symplectic leaf of nonzero dimension. Some criteria of Poisson equivalence are derived from a homotopy argument for coupling Poisson structures. In the case when the transverse Lie algebra of the symplectic leaf is semisimple of compact type, we show that an obstruction to the linearizability is the cohomology class of a Casimir 2-cocycle. This allows us to obtain a semilocal analog of the Conn linearization theorem and to clarify examples of nonlinearizable Poisson structures due to \\cite{DW}.

  9. Continuous orbit equivalence, flow equivalence of Markov shifts and torus actions on Cuntz--Krieger algebras

    OpenAIRE

    Matsumoto, Kengo

    2015-01-01

    We will study torus actions on Cuntz--Krieger algebras trivially acting on its canonical maximal abelian $C^*$-subalgebras from the view points of continuous orbit equivalence of one-sided topological Markov shifts and flow equivalence of two-sided topological Markov shifts.

  10. Strong-interaction shifts and widths of kaonic helium isotopes

    Science.gov (United States)

    Ishiwatari, T.; Bazzi, M.; Beer, G.; Bombelli, L.; Bragadireanu, A.M.; Cargnelli, M.; Curceanu (Petrascu), C.; d?Uffizi, A.; Fiorini, C.; Frizzi, T.; Ghio, F.; Guaraldo, C.; Hayano, R.S.; Iliescu, M.; Iwasaki, M.; Kienle, P.; Levi Sandri, P.; Longoni, A.; Marton, J.; Okada, S.; Pietreanu, D.; Ponta, T.; Rizzo, A.; Romero Vidal, A.; Sbardella, E.; Scordo, A.; Shi, H.; Sirghi, D.L.; Sirghi, F.; Tatsuno, H.; Tudorache, A.; Tudorache, V.; Vazquez Doce, O.; Widmann, E.; Wünschek, B.; Zmeskal, J.

    2013-01-01

    The kaonic 3He and 4He 3d?2p transitions in gaseous targets were observed by the SIDDHARTA experiment. The X-ray energies of these transitions were measured with large-area silicon-drift detectors using the timing information of the K+K? pairs produced by the DA?NE e+e? collider. The strong-interaction shifts and widths both of the kaonic 3He and 4He 2p states were determined, which are much smaller than the results obtained by the previous experiments. The “kaonic helium puzzle” (a discrepancy between theory and experiment) was now resolved. PMID:24068854

  11. Decay widths and total cross sections in perturbative QCD

    Science.gov (United States)

    Surguladze, Levan R.; Samuel, Mark A.

    1996-01-01

    The current status of analytic higher-order perturbative computations of total cross sections and decay widths in Quantum Chromodynamics is reviewed. Important issues are the methodology of renormalization-group evaluations, the ambiguities of the renormalization scheme and its scale, and the technical challenge of calculating many-loop diagrams. As examples, the authors consider the quantities ?tot(e+e--->hadrons) and ?(?--->??+hadrons) up to O(?3s) as well as ?(H-->hadrons) up to O(?2s). The evaluation of the four-loop QED beta function is also described. The problem of theoretical uncertainty estimates in perturbative calculations is briefly discussed.

  12. Decay widths and total cross sections in perturbative QCD

    International Nuclear Information System (INIS)

    The current status of analytic higher-order perturbative computations of total cross sections and decay widths in Quantum Chromodynamics is reviewed. Important issues are the methodology of renormalization-group evaluations, the ambiguities of the renormalization scheme and its scale, and the technical challenge of calculating many-loop diagrams. As examples, the authors consider the quantities ?tot(e+e-?hadrons) and ?(?-???+hadrons) up to O(?3s) as well as ?(H?hadrons) up to O(?2s). The evaluation of the four-loop QED beta function is also described. The problem of theoretical uncertainty estimates in perturbative calculations is briefly discussed. copyright 1996 The American Physical Society

  13. Orbit width scaling of TAE instability growth rate

    International Nuclear Information System (INIS)

    The growth rate of Toroidal Alfven Eigenmodes (TAE) driven unstable by resonant coupling of energetic charged particles is evaluated in the ballooning limit over a wide range of parameters. All damping effects are ignored. Variations in orbit width, aspect ratio, and the ratio of alfven velocity to energetic particle birth velocity, are explored. The relative contribution of passing and trapped particles, and finite Larmor radius effects, are also examined. The phase space location of resonant particles with interact strongly with the modes is described. The accuracy of the analytic results with respect to growth rate magnitude and parametric dependence is investigated by comparison with numerical results

  14. Orbit width scaling of TAE instability growth rate

    International Nuclear Information System (INIS)

    The growth rate of toroidal Alfven eigenmodes (TAEs) driven unstable by resonant coupling of energetic charged particles is evaluated in the 'ballooning' limit over a wide range of parameters. All damping effects are ignored. Variations in orbit width, aspect ratio and the ratio of Alfven velocity to energetic particle 'birth' velocity are explored. The relative contribution of passing and trapped particles, and finite Larmor radius effects, are also examined. The phase space location of resonant particles that interact strongly with the modes is described. The accuracy of the analytic results with respect to growth rate magnitude and parametric dependence is investigated by comparison with numerical results. (author). 16 refs, 8 figs

  15. Total width of 125 GeV Higgs boson.

    Science.gov (United States)

    Barger, Vernon; Ishida, Muneyuki; Keung, Wai-Yee

    2012-06-29

    By using the LHC and Tevatron measurements of the cross sections to various decay channels relative to the standard model Higgs boson, the total width of the putative 125 GeV Higgs boson is determined as 6.1(-2.9)(+7.7) MeV. We describe a way to estimate the branching fraction for the Higgs-boson decay to dark matter. We also discuss a no-go theorem for the ?? signal of the Higgs boson at the LHC. PMID:23004962

  16. Pulse-width modulated DC-DC power converters

    CERN Document Server

    Kazimierczuk, Marian K

    2008-01-01

    This book studies switch-mode power supplies (SMPS) in great detail. This type of converter changes an unregulated DC voltage into a high-frequency pulse-width modulated (PWM) voltage controlled by varying the duty cycle, then changes the PWM AC voltage to a regulated DC voltage at a high efficiency by rectification and filtering. Used to supply electronic circuits, this converter saves energy and space in the overall system. With concept-orientated explanations, this book offers state-of-the-art SMPS technology and promotes an understanding of the principle operations of PWM converters,

  17. Energy detection UWB system based on pulse width modulation

    Directory of Open Access Journals (Sweden)

    Song Cui

    2014-05-01

    Full Text Available A new energy detection ultra-wideband system based on pulse width modulation is proposed. The bit error rate (BER performance of this new system is slightly worst than that of a pulse position modulation (PPM system in additive white Gaussian noise channels. In multipath channels, this system does not suffer from cross-modulation interference as PPM, so it can achieve better BER performance than PPM when cross-modulation interference occurs. In addition, when synchronisation errors occur, this system is more robust than PPM.

  18. Measured Stark widths of several spectral lines of Pb III

    OpenAIRE

    Alonso Medina, Aurelia

    2011-01-01

    The Stark full widths at half of the maximal line intensity (FWHM, ?) have been measured for 25 spectrallines of PbIII (15 measured for the first time) arising from the 5d106s8s, 5d106s7p, 5d106s5f and 5d106s5g electronic configurations, in a lead plasma produced by ablation with a Nd:YAG laser. The optical emission spectroscopy from a laser-induced plasma generated by a 10 640 Å radiation, with an irradiance of 2 × 1010 W cm? 2 on a lead target (99.99% purity) in an atmosphere of argon was a...

  19. Nonlinear Magneto-optic Effects with Ultranarrow Widths

    International Nuclear Information System (INIS)

    Several dispersionlike features in the magnetic field dependence of the nonlinear magneto-optic effect were observed in an experiment performed on rubidium atoms contained in a vapor cell with antirelaxation coating. The narrowest feature has effective resonance width ?=g??Bz?2?x1. 3 Hz , where ?Bz?2.8 ?G is the peak-to-peak separation. The observed nontrivial dependence of the magneto-optic effect on transverse magnetic fields is discussed. The results of this work may be applied to low-field magnetometry, to parity and time reversal invariance violation experiments, etc. copyright 1998 The American Physical Society

  20. Using pulse width modulation for wireless transmission of neural signals in multichannel neural recording systems.

    Science.gov (United States)

    Yin, Ming; Ghovanloo, Maysam

    2009-08-01

    We have used a well-known technique in wireless communication, pulse width modulation (PWM) of time division multiplexed (TDM) signals, within the architecture of a novel wireless integrated neural recording (WINeR) system. We have evaluated the performance of the PWM-based architecture and indicated its accuracy and potential sources of error through detailed theoretical analysis, simulations, and measurements on a setup consisting of a 15-channel WINeR prototype as the transmitter and two types of receivers; an Agilent 89600 vector signal analyzer and a custom wideband receiver, with 36 and 75 MHz of maximum bandwidth, respectively. Furthermore, we present simulation results from a realistic MATLAB-Simulink model of the entire WINeR system to observe the system behavior in response to changes in various parameters. We have concluded that the 15-ch WINeR prototype, which is fabricated in a 0.5- mum standard CMOS process and consumes 4.5 mW from +/-1.5 V supplies, can acquire and wirelessly transmit up to 320 k-samples/s to a 75-MHz receiver with 8.4 bits of resolution, which is equivalent to a wireless data rate of approximately 2.56 Mb/s. PMID:19497823

  1. Equivalent physical models and formulation of equivalent source layer in high-resolution EEG imaging

    International Nuclear Information System (INIS)

    In high-resolution EEG imaging, both equivalent dipole layer (EDL) and equivalent charge layer (ECL) assumed to be located just above the cortical surface have been proposed as high-resolution imaging modalities or as intermediate steps to estimate the epicortical potential. Presented here are the equivalent physical models of these two equivalent source layers (ESL) which show that the strength of EDL is proportional to the surface potential of the layer when the outside of the layer is filled with an insulator, and that the strength of ECL is the normal current of the layer when the outside is filled with a perfect conductor. Based on these equivalent physical models, closed solutions of ECL and EDL corresponding to a dipole enclosed by a spherical layer are given. These results provide the theoretical basis of ESL applications in high-resolution EEG mapping

  2. Derived equivalence of holomorphic symplectic manifolds

    OpenAIRE

    SAWON, Justin

    2004-01-01

    We use twisted Fourier-Mukai transforms to study the relation between an abelian fibration on a holomorphic symplectic manifold and its dual fibration. Our reasoning leads to an equivalence between the derived category of coherent sheaves on one space and the derived category of twisted sheaves on the other space.

  3. Cycle equivalence of graph dynamical systems

    International Nuclear Information System (INIS)

    Graph dynamical systems (GDSs) generalize concepts such as cellular automata and Boolean networks and can describe a wide range of distributed, nonlinear phenomena. Two GDSs are cycle equivalent if their periodic orbits are isomorphic as directed graphs, which captures the notion of having comparable long-term dynamics. In this paper, we study cycle equivalence of GDSs in which the vertex functions are applied sequentially through an update sequence. The main result is a general characterization of cycle equivalence based on the underlying graph Y and the update sequences. We construct and analyse two graphs C(Y) and D(Y) whose connected components contain update sequences that induce cycle equivalent dynamical system maps. The number of components in these graphs, denoted ?(Y) and ?(Y), bound the number of possible long-term behaviour that can be generated by varying the update sequence. We give a recursion relation for ?(Y) which in turn allows us to enumerate ?(Y). The components of C(Y) and D(Y) characterize dynamical neutrality, their sizes represent structural stability of periodic orbits and the number of components can be viewed as a system complexity measure. We conclude with a computational result demonstrating the impact on complexity that results when passing from radius-1 to radius-2 rules in asynchronous cellular automata

  4. Neutron Attenuation Through Borated Tissue Equivalent Material

    International Nuclear Information System (INIS)

    Neutron capture process in biological tissues occurs at low energies and account for a very significant fraction of the tissue dose for very low energy neutrons (thermal and epithermal). Study the behaviour of slow, thermal and epithermal neutron flux emerged through different layers of both water and tissue equivalent material (TEM) was carried out using the transmission method. The water, as reference material, was chosen for all intents and can be considered to be tissue equivalent when corrected for density while tissue equivalent material in the present study was prepared from glycerol, urea, sucrose and water with density of 1.12 g/cm3. In order to enhance the linear energy transfer in the biological tissue, boric acid of different concentrations (up to 3%) was added to the tissue equivalent material. The results show a pronounced peak of flux (consequently the dose) at depth 40 mm followed by an exponential decrease in both water and TEM for slow and thermal neutrons flux without any appearance of this peak in case of epithermal neutrons. Results also show that the maximum values of macroscopic cross sections were appeared at epithermal neutrons for both un borated TEM and all values of boric acid concentrations through TEM.

  5. Equivalent weight of humic acid from peat

    Science.gov (United States)

    Pommer, A.M.; Breger, I.A.

    1960-01-01

    By means of discontinuous titration, the equivalent weight of humic acid isolated from a peat was found to increase from 144 to 183 between the third and fifty-second day after the humic acid was dissolved. Infra-red studies showed that the material had probably condensed with loss of carbonyl groups. ?? 1960.

  6. On the equivalence of multiparameter Gaussian processes

    OpenAIRE

    Sottinen, Tommi; Tudor, Ciprian

    2006-01-01

    Our purpose is to characterize the multiparameter Gaussian processes, that is Gaussian sheets, that are equivalent in law to the Brownian sheet and to the fractional Brownian sheet. We survey multiparameter analogues of the Hitsuda, Girsanov and Shepp representations. As an application, we study a special type of stochastic equation with linear noise.

  7. Reading adn Auditory-Visual Equivalences

    Science.gov (United States)

    Sidman, Murray

    1971-01-01

    A retarded boy, unable to read orally or with comprehension, was taught to match spoken to printed words and was then capable of reading comprehension (matching printed words to picture) and oral reading (naming printed words aloud), demonstrating that certain learned auditory-visual equivalences are sufficient prerequisites for reading…

  8. Are Letter Detection and Proofreading Tasks Equivalent?

    Science.gov (United States)

    Saint-Aubin, Jean; Losier, Marie-Claire; Roy, Macha; Lawrence, Mike

    2015-01-01

    When readers search for misspellings in a proofreading task or for a letter in a letter detection task, they are more likely to omit function words than content words. However, with misspelled words, previous findings for the letter detection task were mixed. In two experiments, the authors tested the functional equivalence of both tasks. Results…

  9. Classification and equivalence in estimation theory

    Science.gov (United States)

    Brockett, R. W.

    1979-01-01

    A method is proposed for classifying estimation problems based on the Lie algebra generated by the operators which appear in the conditional density equation. A natural class of automorphisms of this algebra is examined and a systematic method of generating equivalent problems is developed. Finally, a new class of nonlinear filtering problems with essentially nonlinear filtering equations are presented.

  10. Combining LEP and LHC to bound the Higgs Width

    CERN Document Server

    Englert, Christoph; Spannowsky, Michael

    2015-01-01

    The correlation of on- and off-shell Higgs boson production at the LHC in $gg \\to h^* \\to ZZ$ to bound the Higgs width, under specific model-dependent assumptions, has recently received a lot of attention. As off-shell cross section measurements in this channel suffer from a small signal yield, large backgrounds, and theoretical uncertainties, we propose an alternative complementary constraint which is only possible through the combination of LEP and LHC measurements. Previous precision electroweak measurements at LEP allow for the determination of indirect constraints on Higgs couplings to vector bosons by considering one-loop processes involving virtual Higgs exchange. As the Higgs is off-shell in these diagrams we venture that LEP can be interpreted as an off-shell `Higgs Factory'. By combining these LEP constraints with current LHC 8 TeV Higgs measurements a stronger limit on the Higgs width can be achieved than with LHC data alone for models with rescaled Higgs couplings. Looking to the future, avoiding ...

  11. Dibaryon mass and width calculation with tensor interaction

    International Nuclear Information System (INIS)

    The effect of tensor interaction due to gluon and Goldstone boson exchange on the dibaryon mass and decay width has been studied in the framework of the quark delocalization and colour screening model. The effective S-D wave transition interactions induced by gluon and Goldstone boson exchanges decrease quickly with the increasing channel strangeness, and there is no six-quark state in the light flavour world, which can become a bound one by the help of these tensor interactions, except for the deuteron. The K and ? meson exchange effect has been show to be negligible after a short-range truncation in this model approach. The partial D-wave decay widths, from the N? state to the ?? final states of spins 0 and 1, are 20.7 keV and 63.1 keV respectively. This is a very narrow dibaryon resonance, that might be detected in the relativistic heavy ion reaction by the existing RHIC detectors through the reconstruction of the ?? vertex mass and by the future COMPAS detector at CERN and the FAIR project in Germany

  12. Two-photon partial widths of tensor mesons

    International Nuclear Information System (INIS)

    Partial widths of the ?? decay of the tensor qq-bar quark-antiquark states ?2(1320), f2(1270), f2(1525), their radial excitations ?2(1660), f2(1640), f2(1800), as well as 3F2qq-bar states, are calculated. Calculations are performed in the framework of the same approach which was used before for the study of radiative decays f0(980) ? ??, ?0(980) ? ??, and ?(1020) ? ?f0(980): the assumption made is that of qq-bar quark-antiquark structure of f0(980) and ?0(980). The description of the decay partial widths for ?2(1320), f2(1270), f2(1525) and f0(980), ?0(980) is reached with the approximately equal radial wave functions, thus giving a strong argument in favor of the fact that these scalar and tensor mesons are to be classified as members of the same P-wave qq-bar quark-antiquark multiplet

  13. Fractal Reference Signals in Pulse-Width Modulation

    Science.gov (United States)

    Lurie, Boris; Lurie, Helen

    2005-01-01

    A report proposes the use of waveforms having fractal shapes reminiscent of sawteeth (in contradistinction to conventional regular sawtooth waveforms) as reference signals for pulse-width modulation in control systems for thrusters of spacecraft flying in formation. Fractal reference signals may also be attractive in some terrestrial control systems - especially those in which pulse-width modulation is used for precise control of electric motors. The report asserts that the use of fractal reference signals would enable the synchronous control of several variables of a spacecraft formation, such that consumption of propellant would be minimized, intervals between thruster firings would be long (as preferred for performing scientific observations), and delays in controlling large-thrust maneuvers for retargeting would be minimized. The report further asserts that whereas different controllers would be needed for different modes of operation if conventional pulsewidth modulation were used, the use of fractal reference signals would enable the same controller to function nearly optimally in all regimes of operation, so that only this one controller would be needed.

  14. Varying Vector Pulse Width Modulation for Three Phase Inverter

    Directory of Open Access Journals (Sweden)

    Raju J

    2014-06-01

    Full Text Available This paper mainly deals with designing a control scheme to eliminate the OFF STATE (T0 state present in a Space Vector Pulse-Width Modulation; this has been achieved by redesigning the equations for calculating the reference vector of modulating signal (Vref. In widely used Space Vector Pulse Width Modulation Vmax of carrier signal is greater than Vref of modulating signal (except when Vref = Vmax. Thus during this state the drive goes into the OFF STATE (T0 state. T0 States are similar mirror image states; hence they have no good or bad effect on the system. But there is an amount of switching loss occurring when the switch executes the T0 state. The new equations for reference vector resulted in reducing the switching losses to half the actual value. Also it has various other advantages like. Increase in DC-Link utilization from 15.47 to 21.14 at 2 KHz carrier frequency and Reduction in THD of the system compared to widely used SVPWM.

  15. Determination of the width of the top quark

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, Victor Mukhamedovich; /Dubna, JINR; Abbott, Braden Keim; /Oklahoma U.; Abolins, Maris A.; /Michigan State U.; Acharya, Bannanje Sripath; /Tata Inst.; Adams, Mark Raymond; /Illinois U., Chicago; Adams, Todd; /Florida State U.; Alexeev, Guennadi D.; /Dubna, JINR; Alkhazov, Georgiy D.; /St. Petersburg, INP; Alton, Andrew K.; /Michigan U. /Augustana Coll., Sioux Falls; Alverson, George O.; /Northeastern U.; Alves, Gilvan Augusto; /Rio de Janeiro, CBPF /Nijmegen U.

    2010-09-01

    We extract the total width of the top quark, {Lambda}{sub t}, from the partial decay width {Lambda}(t {yields} Wb) measured using the t-channel cross section for single top quark production and from the branching fraction B(t {yields} Wb) measured in t{bar t} events using up to 2.3 fb{sup -1} of integrated luminosity collected by the D0 Collaboration at the Tevatron p{bar p} Collider. The result is {Lambda}{sub t} = 1.99{sub -0.55}{sup +0.69} GeV, which translates to a top-quark lifetime of {tau}{sub t} = (3.3{sub -0.9}{sup +1.3}) x 10{sup -25} s. Assuming a high mass fourth generation b{prime} quark and unitarity of the four-generation quark-mixing matrix, we set the first upper limit on |V{sub tb{prime}}| < 0.63 at 95% C.L.

  16. Possible problem with neutron widths from decay-in-flight experiments

    International Nuclear Information System (INIS)

    Recently, several papers have reported neutron widths obtained from decay-in-flight experiments. Many of these widths are larger than they are reasonably expected to be. This paper discusses the results and possible reasons for the discrepancies.

  17. Representing Identity and Equivalence for Scientific Data

    Science.gov (United States)

    Wickett, K. M.; Sacchi, S.; Dubin, D.; Renear, A. H.

    2012-12-01

    Matters of equivalence and identity are central to the stewardship of scientific data. In order to properly prepare for and manage the curation, preservation and sharing of digitally-encoded data, data stewards must be able to characterize and assess the relationships holding between data-carrying digital resources. However, identity-related questions about resources and their information content may not be straightforward to answer: for example, what exactly does it mean to say that two files contain the same data, but in different formats? Information content is frequently distinguished from particular representations, but there is no adequately developed shared understanding of what this really means and how the relationship between content and its representations hold. The Data Concepts group at the Center for Informatics Research in Science and Scholarship (CIRSS), University of Illinois at Urbana Champaign, is developing a logic-based framework of fundamental concepts related to scientific data to support curation and integration. One project goal is to develop precise accounts of information resources carrying the same data. We present two complementary conceptual models for information representation: the Basic Representation Model (BRM) and the Systematic Assertion Model (SAM). We show how these models provide an analytical account of digitally-encoded scientific data and a precise understanding of identity and equivalence. The Basic Representation Model identifies the core entities and relationships involved in representing information carried by digital objects. In BRM, digital objects are symbol structures that express propositional content, and stand in layered encoding relationships. For example, an RDF description may be serialized as either XML or N3, and those expressions in turn may be encoded as either UTF-8 or UTF-16 sequences. Defining this encoding stack reveals distinctions necessary for a precise account of identity and equivalence relationships. The Systematic Assertion Model focuses on key provenance events through which propositional content and symbol structures acquire the status of data content and data, respectively. Attention is on events such as a selection of symbols to express propositional content, or an appeal to observational evidence to advance a claim. SAM explicitly identifies data as the primary form of expression the one directly expressing content for a systematic assertion, an assertion where claims are warranted by an observation or a computation event. Under these models, equivalence relationships may hold between different data expressing the same content, or between different encodings of the same data. Equivalence relationships also hold among different data supporting the same claim and when contrasting claims are based on the same observations. SAM and BRM support a fine-grained characterization of scientific equivalence relationships that can be documented through ordinary data stewardship practices.

  18. Library of high and mid-resolution spectra in the CaII H & K, H$\\alpha$, H$\\beta$, NaI D$_1$, D$_2$, and HeI D$_3$ line regions of F, G, K and M field stars

    CERN Document Server

    Montes, D; Fernández-Figueroa, M J; Cornide, M; De Castro, E

    1996-01-01

    In this work we present spectroscopic observations centered in the spectral lines most widely used as optical indicators of chromospheric activity (H{alpha}, H{beta}, Ca II H & K, and He I D{3}) in a sample of F, G, K and M chromospherically inactive stars. The spectra have been obtained with the aim of providing a library of high and mid-resolution spectra to be used in the application of the spectral subtraction technique to obtain the active-chromosphere contribution to these lines in chromospherically active single and binary stars. This library can also be used for spectral classification purposes. A digital version with all the spectra is available via ftp and the World Wide Web (WWW) in both ASCII and FITS formats

  19. Gaussian Radial and Kernel Networks with Varying and Fixed Widths.

    Czech Academy of Sciences Publication Activity Database

    K?rková, V?ra

    Vol. 2. Prague : Institute of Computer Science AS CR, 2013 - (van Emde Boas, P.; Groen, F.; Italiano , G.; Nawrocki, J.; Sack, H.), s. 95-102 ISBN 978-80-87136-15-7. [SOFSEM 2013. Conference on Current Trends in Theory and Practice of Computer Science /39./. Špindler?v Mlýn (CZ), 26.01.2013-31.01.2013] R&D Projects: GA ?R GAP202/11/1368 Institutional support: RVO:67985807 Keywords : Gaussian radial and kernel networks * functionally equivalent networks * universal approximators * stabilizers defined by Gaussian kernels Subject RIV: IN - Informatics, Computer Science

  20. Failure of ad valorem and specific tax equivalence under uncertainty

    OpenAIRE

    Goerke, Laszlo; Herzberg, Frederik; Upmann, Thorsten

    2012-01-01

    Applying a framework of perfect competition under uncertainty, we contribute to the discussion of whether or not ad valorem taxes and specific taxes are equivalent. While this equivalence holds without price uncertainty, we show that ad valorem taxes and specific taxes are almost never equivalent in the presence of uncertainty if we demand equivalence to hold pathwise. Since we obtain this result under perfect competition, our analysis also provides a further rationale for why the equivalence...