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Sample records for cosmic origins spectrograph

  1. Status and Performance Updates for the Cosmic Origins Spectrograph

    Science.gov (United States)

    Snyder, Elaine M.; De Rosa, Gisella; Fischer, William J.; Fix, Mees; Fox, Andrew; Indriolo, Nick; James, Bethan; Oliveira, Cristina M.; Penton, Steven V.; Plesha, Rachel; Rafelski, Marc; Roman-Duval, Julia; Sahnow, David J.; Sankrit, Ravi; Taylor, Joanna M.; White, James

    2018-01-01

    The Hubble Space Telescope's Cosmic Origins Spectrograph (COS) moved the spectra on the FUV detector from Lifetime Position 3 (LP3) to a new pristine location, LP4, in October 2017. The spectra were shifted in the cross-dispersion direction by -2.5" (roughly -31 pixels) from LP3, or -5" (roughly -62 pixels) from the original LP1. This move mitigates the adverse effects of gain sag on the spectral quality and accuracy of COS FUV observations. Here, we present updates regarding the calibration of FUV data at LP4, including the flat fields, flux calibrations, and spectral resolution. We also present updates on the time-dependent sensitivities and dark rates of both the NUV and FUV detectors.

  2. Cosmic Origins Spectrograph: On-Orbit Performance of Target Acquisitions

    Science.gov (United States)

    Penton, Steven V.

    2010-07-01

    COS is a slit-less spectrograph with a very small aperture (R=1.2500). To achieve the desired wavelength accuracies, HST+COS must center the target to within 0.100 of the center of the aperture for the FUV channel, and 0.0400 for NUV. During SMOV and early Cycle 17 we fine-tuned the COS target acquisition (TA) procedures to exceed this accuracy for all three COS TA modes; NUV imaging, NUV spectroscopic, and FUV spectroscopic. In Cycle 17, we also adjusted the COSto- FGS offsets in the SIAF file. This allows us to recommend skipping the time consuming ACQ/SEARCH in cases where the target coordinates are well known. Here we will compare the on-orbit performance of all COS TA modes in terms of centering accuracy, efficiency, and required signal-to-noise (S/N).

  3. COSMIC ORIGINS SPECTROGRAPH OBSERVATIONS OF TRANSLUCENT CLOUDS: Cyg OB2 8A

    International Nuclear Information System (INIS)

    Snow, Theodore P.; Destree, Joshua D.; Burgh, Eric B.; Ferguson, Ryan M.; Danforth, Charles W.; Cordiner, Martin

    2010-01-01

    Data from the Cosmic Origins Spectrograph (COS) are presented for the first highly reddened target (Cyg OB2 8A) under the COS Science Team's guaranteed time allocation. Column densities of ionic, atomic, and molecular species are reported and implications are discussed. Data from Cyg OB2 8A demonstrate the ability to analyze highly reddened interstellar sight lines with the COS that were unavailable to previous UV instruments. Measured column densities indicate that the Cyg OB2 8A line of sight contains multiple diffuse clouds rather than a dominant translucent cloud.

  4. Investigating the Lyman photon escape in local starburst galaxies with the Cosmic Origins Spectrograph

    Science.gov (United States)

    Hernandez, Svea; Leitherer, Claus; Boquien, Médéric; Buat, Véronique; Burgarella, Denis; Calzetti, Daniela; Noll, Stefan

    2018-04-01

    We present a study of 7 star-forming galaxies from the Cosmic Evolution Survey (COSMOS) observed with the Cosmic Origins Spectrograph (COS) on board the Hubble Space Telescope (HST). The galaxies are located at relatively low redshifts, z ˜0.3, with morphologies ranging from extended and disturbed to compact and smooth. To complement the HST observations we also analyze observations taken with the VIMOS spectrograph on the Very Large Telescope (VLT). In our galaxy sample we identify three objects with double peak Lyman-α profiles similar to those seen in Green Pea compact galaxies and measure peak separations of 655, 374, and 275 km s-1. We measure Lyman-α escape fractions with values ranging between 5-13%. Given the low flux levels in the individual COS exposures we apply a weighted stacking approach to obtain a single spectrum. From this COS combined spectrum we infer upper limits for the absolute and relative Lyman continuum escape fractions of f_abs(LyC) = 0.4^{+10.1}_{-0.4}% and f_res(LyC) = 1.7^{+15.2}_{-1.7}%, respectively. Finally, we find that most of these galaxies have moderate UV and optical SFRs (SFRs ≲ 10 M⊙ yr-1).

  5. A SEARCH FOR SHORT-PERIOD ROCKY PLANETS AROUND WDs WITH THE COSMIC ORIGINS SPECTROGRAPH (COS)

    Energy Technology Data Exchange (ETDEWEB)

    Sandhaus, Phoebe H.; Debes, John H.; Ely, Justin; Hines, Dean C.; Bourque, Matthew [Space Telescope Science Institute, 3700 San Martin Dr., Baltimore, MD 21218 (United States)

    2016-05-20

    The search for transiting habitable exoplanets has broadened to include several types of stars that are smaller than the Sun in an attempt to increase the observed transit depth and hence the atmospheric signal of the planet. Of all spectral types, white dwarfs (WDs) are the most favorable for this type of investigation. The fraction of WDs that possess close-in rocky planets is unknown, but several large angle stellar surveys have the photometric precision and cadence to discover at least one if they are common. Ultraviolet observations of WDs may allow for detection of molecular oxygen or ozone in the atmosphere of a terrestrial planet. We use archival Hubble Space Telescope data from the Cosmic Origins Spectrograph to search for transiting rocky planets around UV-bright WDs. In the process, we discovered unusual variability in the pulsating WD GD 133, which shows slow sinusoidal variations in the UV. While we detect no planets around our small sample of targets, we do place stringent limits on the possibility of transiting planets, down to sub-lunar radii. We also point out that non-transiting small planets in thermal equilibrium are detectable around hotter WDs through infrared excesses, and identify two candidates.

  6. COS2025: Extending the Lifetime of the FUV channel of the Cosmic Origins Spectrograph to 2025

    Science.gov (United States)

    Rafelski, Marc; De Rosa, Gisella; Fischer, William J.; Fix, Mees; Fox, Andrew; Indriolo, Nick; James, Bethan; Magness, Camellia; Oliveira, Cristina M.; Penton, Steven V.; Plesha, Rachel; Roman-Duval, Julia; Sahnow, David J.; Sankrit, Ravi; Snyder, Elaine M.; Taylor, Joanna M.; White, James

    2018-01-01

    The Hubble Space Telescope's Cosmic Origins Spectrograph (COS) Far-Ultraviolet (FUV) microchannel plate detector's efficiency at converting incoming photons into detectable events decreases with usage. This depletion of the detector's gain (i.e. gain sag) results in unusable regions of the COS/FUV detector. In order to mitigate this gain sag, a number of strategies have been employed over the past 8 years of operations, ranging from moving to different lifetime positions, to managing the high voltage to extract a smaller amount of charge, to re-distributing the cenwave usage so that Ly-alpha does not produce a gain-sag hole in a given location. We are now at a point where none of the strategies above will, without any other changes, allow us to continue operating the COS/FUV detector to 2025. To address this a new COS2025 policy was developed, with the goal of retaining full science capability of COS/FUV to 2025. We present an overview of the COS2025 policy, which places restrictions on the G130M cenwaves allowed at Lifetime Position 4 (LP4). We also present a tool which allows users to visualize the COS/FUV wavelength ranges to help users prepare their proposals in the light of the restrictions on the G130M cenwaves.

  7. Far-ultraviolet Spectroscopy of Recent Comets with the Cosmic Origins Spectrograph on the Hubble Space Telescope

    Science.gov (United States)

    Feldman, Paul D.; Weaver, Harold A.; A’Hearn, Michael F.; Combi, Michael R.; Dello Russo, Neil

    2018-05-01

    Since its launch in 1990, the Hubble Space Telescope (HST) has served as a platform with unique capabilities for remote observations of comets in the far-ultraviolet region of the spectrum. Successive generations of imagers and spectrographs have seen large advances in sensitivity and spectral resolution enabling observations of the diverse properties of a representative number of comets during the past 25 years. To date, four comets have been observed in the far-ultraviolet by the Cosmic Origins Spectrograph (COS), the last spectrograph to be installed in HST, in 2009: 103P/Hartley 2, C/2009 P1 (Garradd), C/2012 S1 (ISON), and C/2014 Q2 (Lovejoy). COS has unprecedented sensitivity, but limited spatial information in its 2.″5 diameter circular aperture, and our objective was to determine the CO production rates from measurements of the CO Fourth Positive system in the spectral range of 1400–1700 Å. In the two brightest comets, 19 bands of this system were clearly identified. The water production rates were derived from nearly concurrent observations of the OH (0,0) band at 3085 Å by the Space Telescope Imaging Spectrograph. The derived CO/{{{H}}}2{{O}} production rate ratio ranged from ∼0.3% for Hartley 2 to ∼22% for Garradd. In addition, strong partially resolved emission features due to multiplets of S I, centered at 1429 Å and 1479 Å, and of C I at 1561 Å and 1657 Å, were observed in all four comets. Weak emission from several lines of the {{{H}}}2 Lyman band system, excited by solar Lyα and Lyβ pumped fluorescence, were detected in comet Lovejoy.

  8. Space Telescope and Optical Reverberation Mapping Project.I. Ultraviolet Observations of the Seyfert 1 Galaxy NGC 5548 with the Cosmic Origins Spectrograph on Hubble Space Telescope

    NARCIS (Netherlands)

    De Rosa, G.; Peterson, B.M.; Ely, J.; Kriss, G.A.; Crenshaw, D.M.; Horne, K.; Korista, K.T.; Netzer, H.; Pogge, R.W.; Arévalo, P.; Barth, A.J.; Bentz, M.C.; Brandt, W.N.; Breeveld, A.A.; Brewer, B.J.; Dalla Bontà, E.; De Lorenzo-Cáceres, A.; Denney, K.D.; Dietrich, M.; Edelson, R.; Evans, P.A.; Fausnaugh, M.M.; Gehrels, N.; Gelbord, J.M.; Goad, M.R.; Grier, C.J.; Grupe, D.; Hall, P.B.; Kaastra, J.; Kelly, B.C.; Kennea, J.A.; Kochanek, C.S.; Lira, P.; Mathur, S.; McHardy, I.M.; Nousek, J.A.; Pancoast, A.; Papadakis, I.; Pei, L.; Schimoia, J.S.; Siegel, M.; Starkey, D.; Treu, T.; Uttley, P.; Vaughan, S.; Vestergaard, M.; Villforth, C.; Yan, H.; Young, S.; Zu, Y.

    2015-01-01

    We describe the first results from a six-month long reverberation-mapping experiment in the ultraviolet based on 171 observations of the Seyfert 1 galaxy NGC 5548 with the Cosmic Origins Spectrograph on the Hubble Space Telescope. Significant correlated variability is found in the continuum and

  9. Search for trans-iron elements in hot, helium-rich white dwarfs with the HST Cosmic Origins Spectrograph

    Science.gov (United States)

    Hoyer, D.; Rauch, T.; Werner, K.; Kruk, J. W.

    2018-04-01

    The metal abundances in the atmospheres of hot white dwarfs (WDs) entering the cooling sequence are determined by the preceding Asymptotic Giant Branch (AGB) evolutionary phase and, subsequently, by the onset of gravitational settling and radiative levitation. In this paper, we investigate three hot He-rich WDs, which are believed to result from a late He-shell flash. During such a flash, the He-rich intershell matter is dredged up and dominates the surface chemistry. Hence, in contrast to the usual H-rich WDs, their spectra allow direct access to s-process element abundances in the intershell that were synthesized during the AGB stage. In order to look for trans-iron group elements (atomic number Z > 29), we performed a non-local thermodynamic equilibrium model atmosphere analysis of new ultraviolet spectra taken with the Cosmic Origins Spectrograph aboard the Hubble Space Telescope. One of our program stars is of PG 1159 spectral type; this star, PG 1707+427, has effective temperature Teff = 85 000 K, and surface gravity logg = 7.5. The two other stars are DO white dwarfs: WD 0111+002 has Teff = 58 000 K and log g = 7.7, and PG 0109+111 has Teff = 70 000 K and log g = 8.0. These stars trace the onset of element diffusion during early WD evolution. While zinc is the only trans-iron element we could detect in the PG 1159 star, both DOs exhibit lines from Zn, Ga, Ge, Se; one additionally exhibits lines from Sr, Sn, Te, and I and the other from As. Generally, the trans-iron elements are very abundant in the DOs, meaning that radiative levitation must be acting. Most extreme is the almost six orders of magnitude oversolar abundance of tellurium in PG 0109+111. In terms of mass fraction, it is the most abundant metal in the atmosphere. The two DOs join the hitherto unique hot DO RE 0503-289, in which 14 trans-iron elements had even been identified. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which

  10. GALACTIC-SCALE ABSORPTION OUTFLOW IN THE LOW-LUMINOSITY QUASAR IRAS F04250-5718: HUBBLE SPACE TELESCOPE/COSMIC ORIGINS SPECTROGRAPH OBSERVATIONS

    International Nuclear Information System (INIS)

    Edmonds, Doug; Borguet, Benoit; Arav, Nahum; Dunn, Jay P.; Penton, Steve; Kriss, Gerard A.; Korista, Kirk; Bautista, Manuel; Costantini, Elisa; Kaastra, Jelle; Steenbrugge, Katrien; Ignacio Gonzalez-Serrano, J.; Benn, Chris; Aoki, Kentaro; Behar, Ehud; Micheal Crenshaw, D.; Everett, John; Gabel, Jack; Moe, Maxwell; Scott, Jennifer

    2011-01-01

    We present absorption line analysis of the outflow in the quasar IRAS F04250-5718. Far-ultraviolet data from the Cosmic Origins Spectrograph on board the Hubble Space Telescope reveal intrinsic narrow absorption lines from high ionization ions (e.g., C IV, N V, and O VI) as well as low ionization ions (e.g., C II and Si III). We identify three kinematic components with central velocities ranging from ∼-50 to ∼-230 km s -1 . Velocity-dependent, non-black saturation is evident from the line profiles of the high ionization ions. From the non-detection of absorption from a metastable level of C II, we are able to determine that the electron number density in the main component of the outflow is ∼ -3 . Photoionization analysis yields an ionization parameter log U H ∼ -1.6 ± 0.2, which accounts for changes in the metallicity of the outflow and the shape of the incident spectrum. We also consider solutions with two ionization parameters. If the ionization structure of the outflow is due to photoionization by the active galactic nucleus, we determine that the distance to this component from the central source is ∼>3 kpc. Due to the large distance determined for the main kinematic component, we discuss the possibility that this outflow is part of a galactic wind.

  11. Spectrographical method for determining temperature variations of cosmic rays

    International Nuclear Information System (INIS)

    Dorman, L.I.; Krest'yannikov, Yu.Ya.; AN SSSR, Irkutsk. Sibirskij Inst. Zemnogo Magnetizma Ionosfery i Rasprostraneniya Radiovoln)

    1977-01-01

    A spectrographic method for determining [sigmaJsup(μ)/Jsup(μ)]sub(T) temperature variations in cosmic rays is proposed. The value of (sigmaJsup(μ)/Jsup(μ)]sub(T) is determined from three equations for neutron supermonitors and the equation for the muon component of cosmic rays. It is assumed that all the observation data include corrections for the barometric effect. No temperature effect is observed in the neutron component. To improve the reliability and accuracy of the results obtained the surface area of the existing devices and the number of spectrographic equations should be increased as compared with that of the unknown values. The value of [sigmaJsup(μ)/Jsup(μ)]sub(T) for time instants when the aerological probing was carried out, was determined from the data of observations of cosmic rays with the aid of a spectrographic complex of devices of Sib IZMIR. The r.m.s. dispersion of the difference is about 0.2%, which agrees with the expected dispersion. The agreement obtained can be regarded as an independent proof of the correctness of the theory of meteorological effects of cosmic rays. With the existing detection accuracy the spectrographic method can be used for determining the hourly values of temperature corrections for the muon component

  12. Cosmic ray: Studying the origin

    International Nuclear Information System (INIS)

    Szabelski, J.

    1997-01-01

    Investigations of the origin of cosmic rays are presented. Different methods are discussed: studies of cosmic gamma rays of energy from 30 MeV to about 10 15 eV (since photons point to their places of origin), studies of the mass composition of cosmic rays (because it reflects source morphology), and studies of cosmic rays with energy above 1O 19 eV (for these are the highest energies observed in nature). (author)

  13. Cosmic ray: Studying the origin

    Energy Technology Data Exchange (ETDEWEB)

    Szabelski, J. [Cosmic Ray Laboratory, Soltan Institute for Nuclear Studies, Lodz (Poland)

    1997-12-31

    Investigations of the origin of cosmic rays are presented. Different methods are discussed: studies of cosmic gamma rays of energy from 30 MeV to about 10{sup 15} eV (since photons point to their places of origin), studies of the mass composition of cosmic rays (because it reflects source morphology), and studies of cosmic rays with energy above 1O{sup 19} eV (for these are the highest energies observed in nature). (author) 101 refs, 19 figs, 7 tabs

  14. Cosmic ray origin: the way ahead

    International Nuclear Information System (INIS)

    Wolfendale, A W

    2003-01-01

    Despite their discovery being 90 years ago cosmic rays are still characterised by their uncertain masses at high energy and their uncertain origin. This paper deals with the origin problem. The case is put for the majority of the particles being of galactic origin - a generally accepted result. Specific models are put forward for the galactic mechanism and that for the minority extragalactic component

  15. The Keck Cosmic Web Imager (KCWI): A Powerful New Integral Field Spectrograph for the Keck Observatory

    Science.gov (United States)

    Morrissey, Patrick; KCWI Team

    2013-01-01

    The Keck Cosmic Web Imager (KCWI) is a new facility instrument being developed for the W. M. Keck Observatory and funded for construction by the Telescope System Instrumentation Program (TSIP) of the National Science Foundation (NSF). KCWI is a bench-mounted spectrograph for the Keck II right Nasmyth focal station, providing integral field spectroscopy over a seeing-limited field up to 20"x33" in extent. Selectable Volume Phase Holographic (VPH) gratings provide high efficiency and spectral resolution in the range of 1000 to 20000. The dual-beam design of KCWI passed a Preliminary Design Review in summer 2011. The detailed design of the KCWI blue channel (350 to 700 nm) is now nearly complete, with the red channel (530 to 1050 nm) planned for a phased implementation contingent upon additional funding. KCWI builds on the experience of the Caltech team in implementing the Cosmic Web Imager (CWI), in operation since 2009 at Palomar Observatory. KCWI adds considerable flexibility to the CWI design, and will take full advantage of the excellent seeing and dark sky above Mauna Kea with a selectable nod-and-shuffle observing mode. The KCWI team is lead by Caltech (project management, design and implementation) in partnership with the University of California at Santa Cruz (camera optical and mechanical design) and the W. M. Keck Observatory (program oversight and observatory interfaces).

  16. Cosmic Origins Program Annual Technology Report

    Science.gov (United States)

    Pham, Bruce Thai; Neff, Susan Gale

    2016-01-01

    What is the Cosmic Origins (COR) Program? From ancient times, humans have looked up at the night sky and wondered: Are we alone? How did the universe come to be? How does the universe work? COR focuses on the second question. Scientists investigating this broad theme seek to understand the origin and evolution of the universe from the Big Bang to the present day, determining how the expanding universe grew into a grand cosmic web of dark matter enmeshed with galaxies and pristine gas, forming, merging, and evolving over time.

  17. The origin of large scale cosmic structure

    International Nuclear Information System (INIS)

    Jones, B.J.T.; Palmer, P.L.

    1985-01-01

    The paper concerns the origin of large scale cosmic structure. The evolution of density perturbations, the nonlinear regime (Zel'dovich's solution and others), the Gott and Rees clustering hierarchy, the spectrum of condensations, and biassed galaxy formation, are all discussed. (UK)

  18. Astronomers Unveiling Life's Cosmic Origins

    Science.gov (United States)

    2009-02-01

    Processes that laid the foundation for life on Earth -- star and planet formation and the production of complex organic molecules in interstellar space -- are yielding their secrets to astronomers armed with powerful new research tools, and even better tools soon will be available. Astronomers described three important developments at a symposium on the "Cosmic Cradle of Life" at the annual meeting of the American Association for the Advancement of Science in Chicago, IL. Chemistry Cycle The Cosmic Chemistry Cycle CREDIT: Bill Saxton, NRAO/AUI/NSF Full Size Image Files Chemical Cycle Graphic (above image, JPEG, 129K) Graphic With Text Blocks (JPEG, 165K) High-Res TIFF (44.2M) High-Res TIFF With Text Blocks (44.2M) In one development, a team of astrochemists released a major new resource for seeking complex interstellar molecules that are the precursors to life. The chemical data released by Anthony Remijan of the National Radio Astronomy Observatory (NRAO) and his university colleagues is part of the Prebiotic Interstellar Molecule Survey, or PRIMOS, a project studying a star-forming region near the center of our Milky Way Galaxy. PRIMOS is an effort of the National Science Foundation's Center for Chemistry of the Universe, started at the University of Virginia (UVa) in October 2008, and led by UVa Professor Brooks H. Pate. The data, produced by the NSF's Robert C. Byrd Green Bank Telescope (GBT) in West Virginia, came from more than 45 individual observations totalling more than nine GigaBytes of data and over 1.4 million individual frequency channels. Scientists can search the GBT data for specific radio frequencies, called spectral lines -- telltale "fingerprints" -- naturally emitted by molecules in interstellar space. "We've identified more than 720 spectral lines in this collection, and about 240 of those are from unknown molecules," Remijan said. He added, "We're making available to all scientists the best collection of data below 50 GHz ever produced for

  19. The Probe of Inflation and Cosmic Origins

    Science.gov (United States)

    Hanany, Shaul; Inflation Probe Mission Study Team

    2018-01-01

    The Probe of Inflation and Cosmic Origins will map the polarization of the cosmic microwave background over the entire sky with unprecedented sensitivity. It will search for gravity wave signals from the inflationary epoch, thus probing quantum gravity and constraining the energy scale of inflation; it will test the standard model of particle physics by measuring the number of light particles in the Universe and the mass of the neutrino; it will elucidate the nature of dark matter and search for new forms of matter in the early Universe; it will constrain star formation history over cosmic time; and it will determine the mechanisms of structure formation from galaxy cluster to stellar scales. I will review the status of design of this probe-scale mission.

  20. Gamma-ray astronomy and cosmic-ray origin theory

    International Nuclear Information System (INIS)

    Ginzburg, V.L.

    1973-01-01

    A theory of the origin of cosmic radiation is discussed in light of the advances made in gamma-ray astronomy. Arguments against metagalactic models for the origin of cosmic rays are emphasized. (U.S.)

  1. Cosmic Origins Program Annual Technology Report

    Science.gov (United States)

    Pham, Bruce Thai; Neff, Susan Gale

    2015-01-01

    What is the Cosmic Origins (COR) Program? From ancient times, humans have looked up at the night sky and wondered: Are we alone? How did the universe come to be? How does the universe work? COR focuses on the second question. Scientists investigating this broad theme seek to understand the origin and evolution of the universe from the Big Bang to the present day, determining how the expanding universe grew into a grand cosmic web of dark matter enmeshed with galaxies and pristine gas, forming, merging, and evolving over time. COR also seeks to understand how stars and planets form from clouds in these galaxies to create the heavy elements that are essential to life starting with the first generation of stars to seed the universe, and continuing through the birth and eventual death of all subsequent generations of stars. The COR Programs purview includes the majority of the field known as astronomy, from antiquity to the present.

  2. Origins fourteen billion years of cosmic evolution

    CERN Document Server

    Tyson, Neil deGrasse

    2004-01-01

    Origins explores cosmic science's stunning new insights into the formation and evolution of our universe--of the cosmos, of galaxies and galaxy clusters, of stars within galaxies, of planets that orbit those stars, and of different forms of life that take us back to the first three seconds and forward through three billion years of life on Earth to today's search for life on other planets. Drawing on the current cross-pollination of geology, biology and astrophysics, Origins explains the thrilling daily breakthroughs in our knowledge of the universe from dark energy to life on Mars to the mysteries of space and time. Distilling complex science in clear and lively prose, co-authors Neil deGrasse Tyson and Donald Goldsmith conduct a galvanising tour of the cosmos revealing what the universe has been up to while turning part of itself into us.

  3. Exploring cosmic origins with CORE: Inflation

    Science.gov (United States)

    Finelli, F.; Bucher, M.; Achúcarro, A.; Ballardini, M.; Bartolo, N.; Baumann, D.; Clesse, S.; Errard, J.; Handley, W.; Hindmarsh, M.; Kiiveri, K.; Kunz, M.; Lasenby, A.; Liguori, M.; Paoletti, D.; Ringeval, C.; Väliviita, J.; van Tent, B.; Vennin, V.; Ade, P.; Allison, R.; Arroja, F.; Ashdown, M.; Banday, A. J.; Banerji, R.; Bartlett, J. G.; Basak, S.; de Bernardis, P.; Bersanelli, M.; Bonaldi, A.; Borril, J.; Bouchet, F. R.; Boulanger, F.; Brinckmann, T.; Burigana, C.; Buzzelli, A.; Cai, Z.-Y.; Calvo, M.; Carvalho, C. S.; Castellano, G.; Challinor, A.; Chluba, J.; Colantoni, I.; Coppolecchia, A.; Crook, M.; D'Alessandro, G.; D'Amico, G.; Delabrouille, J.; Desjacques, V.; De Zotti, G.; Diego, J. M.; Di Valentino, E.; Feeney, S.; Fergusson, J. R.; Fernandez-Cobos, R.; Ferraro, S.; Forastieri, F.; Galli, S.; García-Bellido, J.; de Gasperis, G.; Génova-Santos, R. T.; Gerbino, M.; González-Nuevo, J.; Grandis, S.; Greenslade, J.; Hagstotz, S.; Hanany, S.; Hazra, D. K.; Hernández-Monteagudo, C.; Hervias-Caimapo, C.; Hills, M.; Hivon, E.; Hu, B.; Kisner, T.; Kitching, T.; Kovetz, E. D.; Kurki-Suonio, H.; Lamagna, L.; Lattanzi, M.; Lesgourgues, J.; Lewis, A.; Lindholm, V.; Lizarraga, J.; López-Caniego, M.; Luzzi, G.; Maffei, B.; Mandolesi, N.; Martínez-González, E.; Martins, C. J. A. P.; Masi, S.; McCarthy, D.; Matarrese, S.; Melchiorri, A.; Melin, J.-B.; Molinari, D.; Monfardini, A.; Natoli, P.; Negrello, M.; Notari, A.; Oppizzi, F.; Paiella, A.; Pajer, E.; Patanchon, G.; Patil, S. P.; Piat, M.; Pisano, G.; Polastri, L.; Polenta, G.; Pollo, A.; Poulin, V.; Quartin, M.; Ravenni, A.; Remazeilles, M.; Renzi, A.; Roest, D.; Roman, M.; Rubiño-Martin, J. A.; Salvati, L.; Starobinsky, A. A.; Tartari, A.; Tasinato, G.; Tomasi, M.; Torrado, J.; Trappe, N.; Trombetti, T.; Tucci, M.; Tucker, C.; Urrestilla, J.; van de Weygaert, R.; Vielva, P.; Vittorio, N.; Young, K.; Zannoni, M.

    2018-04-01

    We forecast the scientific capabilities to improve our understanding of cosmic inflation of CORE, a proposed CMB space satellite submitted in response to the ESA fifth call for a medium-size mission opportunity. The CORE satellite will map the CMB anisotropies in temperature and polarization in 19 frequency channels spanning the range 60–600 GHz. CORE will have an aggregate noise sensitivity of 1.7 μKṡ arcmin and an angular resolution of 5' at 200 GHz. We explore the impact of telescope size and noise sensitivity on the inflation science return by making forecasts for several instrumental configurations. This study assumes that the lower and higher frequency channels suffice to remove foreground contaminations and complements other related studies of component separation and systematic effects, which will be reported in other papers of the series "Exploring Cosmic Origins with CORE." We forecast the capability to determine key inflationary parameters, to lower the detection limit for the tensor-to-scalar ratio down to the 10‑3 level, to chart the landscape of single field slow-roll inflationary models, to constrain the epoch of reheating, thus connecting inflation to the standard radiation-matter dominated Big Bang era, to reconstruct the primordial power spectrum, to constrain the contribution from isocurvature perturbations to the 10‑3 level, to improve constraints on the cosmic string tension to a level below the presumptive GUT scale, and to improve the current measurements of primordial non-Gaussianities down to the fNLlocal inflation. Its capabilities will be further enhanced by combining with complementary future cosmological observations.

  4. On the origin of cosmic magnetic fields

    Science.gov (United States)

    Kulsrud, Russell M.; Zweibel, Ellen G.

    2008-04-01

    We review the extensive and controversial literature concerning how the cosmic magnetic fields pervading nearly all galaxies and clusters of galaxies actually got started. Some observational evidence supports a hypothesis that the field is already moderately strong at the beginning of the life of a galaxy and its disc. One argument involves the chemical abundance of the light elements Be and B, while a second one is based on the detection of strong magnetic fields in very young high red shift galaxies. Since this problem of initial amplification of cosmic magnetic fields involves important plasma problems it is obvious that one must know the plasma in which the amplification occurs. Most of this review is devoted to this basic problem and for this it is necessary to devote ourselves to reviewing studies that take place in environments in which the plasma properties are most clearly understood. For this reason the authors have chosen to restrict themselves almost completely to studies of dynamos in our Galaxy. It is true that one can get a much better idea of the grand scope of galactic fields in extragalactic systems. However, most mature galaxies share the same dilemma as ours of overcoming important plasma problems. Since the authors are both trained in plasma physics we may be biased in pursuing this approach, but we feel it is justified by the above argument. In addition we feel we can produce a better review by staying close to that which we know best. In addition we have chosen not to consider the saturation problem of the galactic magnetic field since if the original dynamo amplification fails the saturation question does not arise. It is generally accepted that seed fields, whose strength is of order 10-20 G, easily spring up in the era preceding galaxy formation. Several mechanisms have been proposed to amplify these seed magnetic fields to a coherent structure with the microgauss strengths of the currently observed galactic magnetic fields. The standard

  5. On the origin of cosmic magnetic fields

    International Nuclear Information System (INIS)

    Kulsrud, Russell M; Zweibel, Ellen G

    2008-01-01

    We review the extensive and controversial literature concerning how the cosmic magnetic fields pervading nearly all galaxies and clusters of galaxies actually got started. Some observational evidence supports a hypothesis that the field is already moderately strong at the beginning of the life of a galaxy and its disc. One argument involves the chemical abundance of the light elements Be and B, while a second one is based on the detection of strong magnetic fields in very young high red shift galaxies. Since this problem of initial amplification of cosmic magnetic fields involves important plasma problems it is obvious that one must know the plasma in which the amplification occurs. Most of this review is devoted to this basic problem and for this it is necessary to devote ourselves to reviewing studies that take place in environments in which the plasma properties are most clearly understood. For this reason the authors have chosen to restrict themselves almost completely to studies of dynamos in our Galaxy. It is true that one can get a much better idea of the grand scope of galactic fields in extragalactic systems. However, most mature galaxies share the same dilemma as ours of overcoming important plasma problems. Since the authors are both trained in plasma physics we may be biased in pursuing this approach, but we feel it is justified by the above argument. In addition we feel we can produce a better review by staying close to that which we know best. In addition we have chosen not to consider the saturation problem of the galactic magnetic field since if the original dynamo amplification fails the saturation question does not arise. It is generally accepted that seed fields, whose strength is of order 10 -20 G, easily spring up in the era preceding galaxy formation. Several mechanisms have been proposed to amplify these seed magnetic fields to a coherent structure with the microgauss strengths of the currently observed galactic magnetic fields. The standard

  6. Cosmic-ray antimatter - A primary origin hypothesis

    Science.gov (United States)

    Stecker, F. W.; Protheroe, R. J.; Kazanas, D.

    1983-01-01

    The present investigation is concerned with the possibility that the observed cosmic-ray protons are of primary extragalactic origin, taking into account the significance of the current antiproton data. Attention is given to questions regarding primary antiprotons, antihelium fluxes, and the propagation of extragalactic cosmic rays. It is concluded that the primary origin hypothesis should be considered as a serious alternative explanation for the cosmic-ray antiproton fluxes. Such extragalactic primary origin can be considered in the context of a baryon symmetric domain cosmology. The fluxes and propagation characteristics suggested are found to be in rough agreement with the present antiproton data.

  7. Cosmic-ray exposure records and origins of meteorites

    International Nuclear Information System (INIS)

    Reedy, R.C.

    1985-01-01

    The cosmic-ray records of meteorites can be used to infer much about their origins and recent histories. Some meteorites had simple cosmic-ray exposure histories, while others had complex exposure histories with their cosmogenic products made both before and after a collision in space. The methods used to interpret meteorites' cosmic-ray records, especially identifying simple or complex exposure histories, often are inadequate. Besides spallogenic radionuclides and stable nuclides, measurements of products that have location-sensitive production rates, such as the tracks of heavy cosmic-ray nuclei or neutron-capture nuclides, are very useful in accurately determining a meteorite's history. Samples from different, known locations of a meteorite help in studying the cosmic-ray record. Such extensive sets of meteorite measurements, plus theoretical modeling of complex histories, will improve our ability to predict the production of cosmogenic nuclides in meteorites, to distinguish simple and complex exposure histories, and to better determine exposure ages

  8. Origin of transient cosmic ray intensity variations

    International Nuclear Information System (INIS)

    Duggal, S.P.; Pomerantz, M.A.

    1977-01-01

    A new approach to determining the solar progenitor of transient cosmic ray intensity variations has revealed that in a statistical sense, solar flares, heretofore regarded as the predominant source of the modulation, actually do not precede the reduction in flux observed at earth. Superposed epoch analysis of the cosmic ray data with respect to the time of occurrence of all 379 solar flares of importance (Imp) < or =2 observed during solar cycle 20 (1964-1974 inclusive) shows that the onset of a decrease in the composite nucleonic intensity at polar stations occurs prior to the zero day (i.e., time of the flare) well before the arrival in the vicinity of earth of the associated solar plasma. The statistical significance of this result is confirmed by comparing the pooled variance determined from Chree analysis of an equal number of random epochs with that of the curve representing the flare epochs. Subdivision of the latter into three groups according to the heliographic longitude of the flares shows that whereas eastern flares might be associated with cosmic ray decreases, central (30degree to -30degree) and western flares cannot be thus related. A similar analysis of all flares of Imp< or =2 that occurred in a selected set of 24 extraordinary flare-rich active centers during 1964--1974 confirms these results and shows that the observed cosmic ray intensity decrease is, in fact, associated with the central meridian passage ( +- 1 day) of the active regions. Thus earlier conclusions concerning relationships between the heliolongitude of flares and their apparent effectiveness in producing Forbush decreases require reevaluation. The specific feature associated with solar active centers that is actually the principal source of transient modulations remanins to be identified

  9. ORIGIN: metal creation and evolution from the cosmic dawn

    NARCIS (Netherlands)

    den Herder, J.W.; Piro, L.; Ohashi, T.; Kouveliotou, C.; Hartmann, D.H.; Kaastra, J.S.; Amati, L.; Andersen, M.I.; Arnaud, M.; Atteia, J.-L.; Bandler, S.; Barbera, M.; Barcons, X.; Barthelmy, S.; Basa, S.; Basso, S.; de Boer, M.; Branchini, E.; Branduardi-Raymont, G.; Borgani, S.; Boyarsky, A.; Brunetti, G.; Budtz-Jorgensen, C.; Burrows, D.; Butler, N.; Campana, S.; Caroli, E.; Ceballos, M.; Christensen, F.; Churazov, E.; Comastri, A.; Colasanti, L.; Cole, R.; Content, R.; Corsi, A.; Costantini, E.; Conconi, P.; Cusumano, G.; de Plaa, J.; De Rosa, A.; Del Santo, M.; Di Cosimo, S.; De Pasquale, M.; Doriese, R.; Ettori, S.; Evans, P.; Ezoe, Y.; Ferrari, L.; Finger, H.; Figueroa-Feliciano, T.; Friedrich, P.; Fujimoto, R.; Furuzawa, A.; Fynbo, J.; Gatti, F.; Galeazzi, M.; Gehrels, N.; Gendre, B.; Ghirlanda, G.; Ghisellini, G.; Gilfanov, M.; Giommi, P.; Girardi, M.; Grindlay, J.; Cocchi, M.; Godet, O.; Guedel, M.; Haardt, F.; Hartog, R.; Hepburn, I.; Hermsen, W.; Hjorth, J.; Hoekstra, H.; Holland, A.; Hornstrup, A.; van der Horst, A.; Hoshino, A.; in 't Zand, J.; Irwin, K.; Ishisaki, Y.; Jonker, P.; Kitayama, T.; Kawahara, H.; Kawai, N.; Kelley, R.; Kilbourne, C.; de Korte, P.; Kusenko, A.; Kuvvetli, I.; Labanti, M.; Macculi, C.; Maiolino, R.; Mas Hesse, M.; Matsushita, K.; Mazzotta, P.; McCammon, D.; Méndez, M.; Mignani, R.; Mineo, T.; Mitsuda, K.; Mushotzky, R.; Molendi, S.; Moscardini, L.; Natalucci, L.; Nicastro, F.; O'Brien, P.; Osborne, J.; Paerels, F.; Page, M.; Paltani, S.; Pedersen, K.; Perinati, E.; Ponman, T.; Pointecouteau, E.; Predehl, P.; Porter, S.; Rasmussen, A.; Rauw, G.; Röttgering, H.; Roncarelli, M.; Rosati, P.; Quadrini, E.; Ruchayskiy, O.; Salvaterra, R.; Sasaki, S.; Sato, K.; Savaglio, S.; Schaye, J.; Sciortino, S.; Shaposhnikov, M.; Sharples, R.; Shinozaki, K.; Spiga, D.; Sunyaev, R.; Suto, Y.; Takei, Y.; Tanvir, N.; Tashiro, M.; Tamura, T.; Tawara, Y.; Troja, E.; Tsujimoto, M.; Tsuru, T.; Ubertini, P.; Ullom, J.; Ursino, E.; Verbunt, F.; van de Voort, F.; Viel, M.; Wachter, S.; Watson, D.; Weisskopf, M.; Werner, N.; White, N.; Willingale, R.; Wijers, R.; Yamasaki, N.; Yoshikawa, K.; Zane, S.

    2012-01-01

    ORIGIN is a proposal for the M3 mission call of ESA aimed at the study of metal creation from the epoch of cosmic dawn. Using high-spectral resolution in the soft X-ray band, ORIGIN will be able to identify the physical conditions of all abundant elements between C and Ni to red-shifts of z = 10,

  10. ORIGIN : Metal creation and evolution from the cosmic dawn

    NARCIS (Netherlands)

    den Herder, Jan-Willem; Piro, Luigi; Ohashi, Takaya; Kouveliotou, Chryssa; Hartmann, Dieter H.; Kaastra, Jelle S.; Amati, L.; Andersen, M. I.; Arnaud, M.; Attéia, J.-L.; Bandler, S.; Barbera, M.; Barcons, X.; Barthelmy, S.; Basa, S.; Basso, S.; Boer, M.; Branchini, E.; Branduardi-Raymont, G.; Borgani, S.; Boyarsky, A.; Brunetti, G.; Budtz-Jorgensen, C.; Burrows, D.; Butler, N.; Campana, S.; Caroli, E.; Ceballos, M.; Christensen, F.; Churazov, E.; Comastri, A.; Colasanti, L.; Cole, R.; Content, R.; Corsi, A.; Costantini, E.; Conconi, P.; Cusumano, G.; de Plaa, J.; De Rosa, A.; Del Santo, M.; Di Cosimo, S.; De Pasquale, M.; Doriese, R.; Ettori, S.; Evans, P.; Ezoe, Y.; Ferrari, L.; Finger, H.; Figueroa-Feliciano, T.; Friedrich, P.; Fujimoto, R.; Furuzawa, A.; Fynbo, J.; Gatti, F.; Galeazzi, M.; Gehrels, N.; Gendre, B.; Ghirlanda, G.; Ghisellini, G.; Gilfanov, M.; Giommi, P.; Girardi, M.; Grindlay, J.; Cocchi, M.; Godet, O.; Guedel, M.; Haardt, F.; den Hartog, R.; Hepburn, I.; Hermsen, W.; Hjorth, J.; Hoekstra, H.; Holland, A.; Hornstrup, A.; van der Horst, A.; Hoshino, A.; in't Zand, J.; Irwin, K.; Ishisaki, Y.; Jonker, P.; Kitayama, T.; Kawahara, H.; Kawai, N.; Kelley, R.; Kilbourne, C.; de Korte, P.; Kusenko, A.; Kuvvetli, I.; Labanti, M.; Macculi, C.; Maiolino, R.; Hesse, M. Mas; Matsushita, K.; Mazzotta, P.; McCammon, D.; Méndez, M.; Mignani, R.; Mineo, T.; Mitsuda, K.; Mushotzky, R.; Molendi, S.; Moscardini, L.; Natalucci, L.; Nicastro, F.; O'Brien, P.; Osborne, J.; Paerels, F.; Page, M.; Paltani, S.; Pedersen, K.; Perinati, E.; Ponman, T.; Pointecouteau, E.; Predehl, P.; Porter, S.; Rasmussen, A.; Rauw, G.; Röttgering, H.; Roncarelli, M.; Rosati, P.; Quadrini, E.; Ruchayskiy, O.; Salvaterra, R.; Sasaki, S.; Sato, K.; Savaglio, S.; Schaye, J.; Sciortino, S.; Shaposhnikov, M.; Sharples, R.; Shinozaki, K.; Spiga, D.; Sunyaev, R.; Suto, Y.; Takei, Y.; Tanvir, N.; Tashiro, M.; Tamura, T.; Tawara, Y.; Troja, E.; Tsujimoto, M.; Tsuru, T.; Ubertini, P.; Ullom, J.; Ursino, E.; Verbunt, F.; van de Voort, F.; Viel, M.; Wachter, S.; Watson, D.; Weisskopf, M.; Werner, N.; White, N.; Willingale, R.; Wijers, R.; Yamasaki, N.; Yoshikawa, K.; Zane, S.

    2012-01-01

    ORIGIN is a proposal for the M3 mission call of ESA aimed at the study of metal creation from the epoch of cosmic dawn. Using high-spectral resolution in the soft X-ray band, ORIGIN will be able to identify the physical conditions of all abundant elements between C and Ni to red-shifts of z = 10,

  11. Origin and propagation of galactic cosmic rays

    Science.gov (United States)

    Cesarsky, Catherine J.; Ormes, Jonathan F.

    1987-01-01

    The study of systematic trends in elemental abundances is important for unfolding the nuclear and/or atomic effects that should govern the shaping of source abundances and in constraining the parameters of cosmic ray acceleration models. In principle, much can be learned about the large-scale distributions of cosmic rays in the galaxy from all-sky gamma ray surveys such as COS-B and SAS-2. Because of the uncertainties in the matter distribution which come from the inability to measure the abundance of molecular hydrogen, the results are somewhat controversial. The leaky-box model accounts for a surprising amount of the data on heavy nuclei. However, a growing body of data indicates that the simple picture may have to be abandoned in favor of more complex models which contain additional parameters. Future experiments on the Spacelab and space station will hopefully be made of the spectra of individual nuclei at high energy. Antiprotons must be studied in the background free environment above the atmosphere with much higher reliability and presion to obtain spectral information.

  12. Identifying Galactic Cosmic Ray Origins With Super-TIGER

    Science.gov (United States)

    deNolfo, Georgia; Binns, W. R.; Israel, M. H.; Christian, E. R.; Mitchell, J. W.; Hams, T.; Link, J. T.; Sasaki, M.; Labrador, A. W.; Mewaldt, R. A.; hide

    2009-01-01

    Super-TIGER (Super Trans-Iron Galactic Element Recorder) is a new long-duration balloon-borne instrument designed to test and clarify an emerging model of cosmic-ray origins and models for atomic processes by which nuclei are selected for acceleration. A sensitive test of the origin of cosmic rays is the measurement of ultra heavy elemental abundances (Z > or equal 30). Super-TIGER is a large-area (5 sq m) instrument designed to measure the elements in the interval 30 TIGER builds on the heritage of the smaller TIGER, which produced the first well-resolved measurements of elemental abundances of the elements Ga-31, Ge-32, and Se-34. We present the Super-TIGER design, schedule, and progress to date, and discuss the relevance of UH measurements to cosmic-ray origins.

  13. Gamma ray astronomy and the origin of galactic cosmic rays

    International Nuclear Information System (INIS)

    Gabici, Stefano

    2011-01-01

    Diffusive shock acceleration operating at expanding supernova remnant shells is by far the most popular model for the origin of galactic cosmic rays. Despite the general consensus received by the model, an unambiguous and conclusive proof of the supernova remnant hypothesis is still missing. In this context, the recent developments in gamma ray astronomy provide us with precious insights into the problem of the origin of galactic cosmic rays, since production of gamma rays is expected both during the acceleration of cosmic rays at supernova remnant shocks and during their subsequent propagation in the interstellar medium. In particular, the recent detection of a number of supernova remnants at TeV energies nicely fits with the model, but it still does not constitute a conclusive proof of it, mainly due to the difficulty of disentangling the hadronic and leptonic contributions to the observed gamma ray emission. The main goal of my research is to search for an unambiguous and conclusive observational test for proving (or disproving) the idea that supernova remnants are the sources of galactic cosmic rays with energies up to (at least) the cosmic ray knee. Our present comprehension of the mechanisms of particle acceleration at shocks and of the propagation of cosmic rays in turbulent magnetic fields encourages beliefs that such a conclusive test might come from future observations of supernova remnants and of the Galaxy in the almost unexplored domain of multi-TeV gamma rays. (author)

  14. The origin of very high cosmic rays

    International Nuclear Information System (INIS)

    Colgate, S.A.

    1975-01-01

    There are now two arguments that indicate that the whole cosmic ray spectrum is created in every galaxy, primarily Sc galaxies, and furthermore, that the source(s) should be occuring randomly such as supernova approximately = 1 per 50 years. The canonical source must produce a flatter spectrum by E +1 for E > 10 15 eV so that galactic leakage approximately E**-1 gives the observed slope, E 18 eV. For E > 3 x 10 18 eV all galaxies contribute to the extragalactic flux which equals approximately the galactic flux. Anisotropy occurs because of the statistical probability that several sources (supernovae) occur in this galaxy in the time and position such as to give rise to a flux greater than the extragalactic flux. (orig./BJ) [de

  15. Origin of the highest energy cosmic rays

    Energy Technology Data Exchange (ETDEWEB)

    Biermann, Peter L.; Ahn, Eun-Joo; Medina-Tanco, Gustavo; Stanev, Todor

    2000-06-01

    Introducing a simple Galactic wind model patterned after the solar wind we show that back-tracing the orbits of the highest energy cosmic events suggests that they may all come from the Virgo cluster, and so probably from the active radio galaxy M87. This confirms a long standing expectation. Those powerful radio galaxies that have their relativistic jets stuck in the interstellar medium of the host galaxy, such as 3C147, will then enable us to derive limits on the production of any new kind of particle, expected in some extensions of the standard model in particle physics. New data from HIRES will be crucial in testing the model proposed here.

  16. Cosmic-ray exposure records and origins of meteorites

    International Nuclear Information System (INIS)

    Reedy, R.C.

    1985-01-01

    The cosmic-ray records of meteorites are used to infer much about their origins and recent histories. The methods used to interpret meteorites cosmic-ray records, especially identifying simple or complex exposure histories, often are inadequate. Spallogenic radionuclides, stable nuclides, and measurements of products that have location-sensitive production rates, such as the tracks of heavy cosmic-ray nuclei or neutron-capture nuclides, are very useful in accurately determining a meteorite's history. Samples from different, known locations of a meteorite help in studying the cosmic-ray record. Such extensive sets of meteorite measuremetns, plus theoretical modeling of complex histories, improves the ability to predict the production of cosmogenic nuclides in meteorites, to distinguish simple and complex exposure histories, and to better determine exposure ages

  17. Exploring cosmic origins with CORE: Cosmological parameters

    Science.gov (United States)

    Di Valentino, E.; Brinckmann, T.; Gerbino, M.; Poulin, V.; Bouchet, F. R.; Lesgourgues, J.; Melchiorri, A.; Chluba, J.; Clesse, S.; Delabrouille, J.; Dvorkin, C.; Forastieri, F.; Galli, S.; Hooper, D. C.; Lattanzi, M.; Martins, C. J. A. P.; Salvati, L.; Cabass, G.; Caputo, A.; Giusarma, E.; Hivon, E.; Natoli, P.; Pagano, L.; Paradiso, S.; Rubiño-Martin, J. A.; Achúcarro, A.; Ade, P.; Allison, R.; Arroja, F.; Ashdown, M.; Ballardini, M.; Banday, A. J.; Banerji, R.; Bartolo, N.; Bartlett, J. G.; Basak, S.; Baumann, D.; de Bernardis, P.; Bersanelli, M.; Bonaldi, A.; Bonato, M.; Borrill, J.; Boulanger, F.; Bucher, M.; Burigana, C.; Buzzelli, A.; Cai, Z.-Y.; Calvo, M.; Carvalho, C. S.; Castellano, G.; Challinor, A.; Charles, I.; Colantoni, I.; Coppolecchia, A.; Crook, M.; D'Alessandro, G.; De Petris, M.; De Zotti, G.; Diego, J. M.; Errard, J.; Feeney, S.; Fernandez-Cobos, R.; Ferraro, S.; Finelli, F.; de Gasperis, G.; Génova-Santos, R. T.; González-Nuevo, J.; Grandis, S.; Greenslade, J.; Hagstotz, S.; Hanany, S.; Handley, W.; Hazra, D. K.; Hernández-Monteagudo, C.; Hervias-Caimapo, C.; Hills, M.; Kiiveri, K.; Kisner, T.; Kitching, T.; Kunz, M.; Kurki-Suonio, H.; Lamagna, L.; Lasenby, A.; Lewis, A.; Liguori, M.; Lindholm, V.; Lopez-Caniego, M.; Luzzi, G.; Maffei, B.; Martin, S.; Martinez-Gonzalez, E.; Masi, S.; Matarrese, S.; McCarthy, D.; Melin, J.-B.; Mohr, J. J.; Molinari, D.; Monfardini, A.; Negrello, M.; Notari, A.; Paiella, A.; Paoletti, D.; Patanchon, G.; Piacentini, F.; Piat, M.; Pisano, G.; Polastri, L.; Polenta, G.; Pollo, A.; Quartin, M.; Remazeilles, M.; Roman, M.; Ringeval, C.; Tartari, A.; Tomasi, M.; Tramonte, D.; Trappe, N.; Trombetti, T.; Tucker, C.; Väliviita, J.; van de Weygaert, R.; Van Tent, B.; Vennin, V.; Vermeulen, G.; Vielva, P.; Vittorio, N.; Young, K.; Zannoni, M.

    2018-04-01

    We forecast the main cosmological parameter constraints achievable with the CORE space mission which is dedicated to mapping the polarisation of the Cosmic Microwave Background (CMB). CORE was recently submitted in response to ESA's fifth call for medium-sized mission proposals (M5). Here we report the results from our pre-submission study of the impact of various instrumental options, in particular the telescope size and sensitivity level, and review the great, transformative potential of the mission as proposed. Specifically, we assess the impact on a broad range of fundamental parameters of our Universe as a function of the expected CMB characteristics, with other papers in the series focusing on controlling astrophysical and instrumental residual systematics. In this paper, we assume that only a few central CORE frequency channels are usable for our purpose, all others being devoted to the cleaning of astrophysical contaminants. On the theoretical side, we assume ΛCDM as our general framework and quantify the improvement provided by CORE over the current constraints from the Planck 2015 release. We also study the joint sensitivity of CORE and of future Baryon Acoustic Oscillation and Large Scale Structure experiments like DESI and Euclid. Specific constraints on the physics of inflation are presented in another paper of the series. In addition to the six parameters of the base ΛCDM, which describe the matter content of a spatially flat universe with adiabatic and scalar primordial fluctuations from inflation, we derive the precision achievable on parameters like those describing curvature, neutrino physics, extra light relics, primordial helium abundance, dark matter annihilation, recombination physics, variation of fundamental constants, dark energy, modified gravity, reionization and cosmic birefringence. In addition to assessing the improvement on the precision of individual parameters, we also forecast the post-CORE overall reduction of the allowed

  18. THE ORIGIN OF COSMIC RAYS: WHAT CAN GLAST SAY?

    Energy Technology Data Exchange (ETDEWEB)

    Bloom, Elliott

    2000-10-10

    Gamma rays in the band from 30 MeV to 300 GeV, used in combination with direct measurements and with data from radio and X-ray bands, provide a powerful tool for studying the origin of Galactic cosmic rays. Gamma-ray Large Area Space Telescope (GLAST) with its fine 10-20 arcmin angular resolution will be able to map the sites of acceleration of cosmic rays and their interactions with interstellar matter. It will provide information that is necessary to study the acceleration of energetic particles in supernova shocks, their transport in the interstellar medium and penetration into molecular clouds.

  19. Exploring cosmic origins with CORE: Cluster science

    Science.gov (United States)

    Melin, J.-B.; Bonaldi, A.; Remazeilles, M.; Hagstotz, S.; Diego, J. M.; Hernández-Monteagudo, C.; Génova-Santos, R. T.; Luzzi, G.; Martins, C. J. A. P.; Grandis, S.; Mohr, J. J.; Bartlett, J. G.; Delabrouille, J.; Ferraro, S.; Tramonte, D.; Rubiño-Martín, J. A.; Macìas-Pérez, J. F.; Achúcarro, A.; Ade, P.; Allison, R.; Ashdown, M.; Ballardini, M.; Banday, A. J.; Banerji, R.; Bartolo, N.; Basak, S.; Basu, K.; Battye, R. A.; Baumann, D.; Bersanelli, M.; Bonato, M.; Borrill, J.; Bouchet, F.; Boulanger, F.; Brinckmann, T.; Bucher, M.; Burigana, C.; Buzzelli, A.; Cai, Z.-Y.; Calvo, M.; Carvalho, C. S.; Castellano, M. G.; Challinor, A.; Chluba, J.; Clesse, S.; Colafrancesco, S.; Colantoni, I.; Coppolecchia, A.; Crook, M.; D'Alessandro, G.; de Bernardis, P.; de Gasperis, G.; De Petris, M.; De Zotti, G.; Di Valentino, E.; Errard, J.; Feeney, S. M.; Fernández-Cobos, R.; Finelli, F.; Forastieri, F.; Galli, S.; Gerbino, M.; González-Nuevo, J.; Greenslade, J.; Hanany, S.; Handley, W.; Hervias-Caimapo, C.; Hills, M.; Hivon, E.; Kiiveri, K.; Kisner, T.; Kitching, T.; Kunz, M.; Kurki-Suonio, H.; Lamagna, L.; Lasenby, A.; Lattanzi, M.; Le Brun, A. M. C.; Lesgourgues, J.; Lewis, A.; Liguori, M.; Lindholm, V.; Lopez-Caniego, M.; Maffei, B.; Martinez-Gonzalez, E.; Masi, S.; Mazzotta, P.; McCarthy, D.; Melchiorri, A.; Molinari, D.; Monfardini, A.; Natoli, P.; Negrello, M.; Notari, A.; Paiella, A.; Paoletti, D.; Patanchon, G.; Piat, M.; Pisano, G.; Polastri, L.; Polenta, G.; Pollo, A.; Poulin, V.; Quartin, M.; Roman, M.; Salvati, L.; Tartari, A.; Tomasi, M.; Trappe, N.; Triqueneaux, S.; Trombetti, T.; Tucker, C.; Väliviita, J.; van de Weygaert, R.; Van Tent, B.; Vennin, V.; Vielva, P.; Vittorio, N.; Weller, J.; Young, K.; Zannoni, M.

    2018-04-01

    We examine the cosmological constraints that can be achieved with a galaxy cluster survey with the future CORE space mission. Using realistic simulations of the millimeter sky, produced with the latest version of the Planck Sky Model, we characterize the CORE cluster catalogues as a function of the main mission performance parameters. We pay particular attention to telescope size, key to improved angular resolution, and discuss the comparison and the complementarity of CORE with ambitious future ground-based CMB experiments that could be deployed in the next decade. A possible CORE mission concept with a 150 cm diameter primary mirror can detect of the order of 50,000 clusters through the thermal Sunyaev-Zeldovich effect (SZE). The total yield increases (decreases) by 25% when increasing (decreasing) the mirror diameter by 30 cm. The 150 cm telescope configuration will detect the most massive clusters (>1014 Msolar) at redshift z>1.5 over the whole sky, although the exact number above this redshift is tied to the uncertain evolution of the cluster SZE flux-mass relation; assuming self-similar evolution, CORE will detect 0~ 50 clusters at redshift z>1.5. This changes to 800 (200) when increasing (decreasing) the mirror size by 30 cm. CORE will be able to measure individual cluster halo masses through lensing of the cosmic microwave background anisotropies with a 1-σ sensitivity of 4×1014 Msolar, for a 120 cm aperture telescope, and 1014 Msolar for a 180 cm one. From the ground, we estimate that, for example, a survey with about 150,000 detectors at the focus of 350 cm telescopes observing 65% of the sky would be shallower than CORE and detect about 11,000 clusters, while a survey with the same number of detectors observing 25% of sky with a 10 m telescope is expected to be deeper and to detect about 70,000 clusters. When combined with the latter, CORE would reach a limiting mass of M500 ~ 2‑3 × 1013 Msolar and detect 220,000 clusters (5 sigma detection limit

  20. ORIGIN: Metal Creation and Evolution from the Cosmic Dawn

    DEFF Research Database (Denmark)

    Herder, J. W. den; Piro, L.; Ohashi, T.

    2011-01-01

    , and beyond. The mission will answer questions such as: When were the first metals created? How does the cosmic metal content evolve? Where do most of the metals reside in the Universe? What is the role of metals in structure formation and evolution? To reach out to the early Universe ORIGIN will use Gamma......ORIGIN is a proposal for the M3 mission call of ESA aimed at the study of metal creation from the epoch of cosmic dawn. Using high-spectral resolution in the soft X-ray band, ORIGIN will be able to identify the physical conditions of all abundant elements between C and Ni to red-shifts of z=10...

  1. Synthesis of ideas on cosmic ray origin and propagation

    International Nuclear Information System (INIS)

    Wolfendale, A.W.

    1986-01-01

    An attempt is made, based largely on ideas reported at this Advanced Studies Institute, to synthesise ideas which have been put forward on cosmic ray origin and propagation. The conclusions drawn are as follows. The bulk of cosmic rays detected at earth appear to be of Galactic origin, many probably having come from supernova remnants, at least at the lowest energies. Only above 10/sup 19/ eV does an extragalactic origin appear likely and here the VIRGO cluster at the centre of our Supercluster is a likely source. Although extragalactic cosmic rays are not present to a large extent their energy density could well be significant and the case is made for its being about 10/sup -4/ eV cm/sup -3/. Concerning the controversy about continuous or ''quick'' particle acceleration, it appears necessary to separate origin and acceleration. The interesting model put forward by Schlickeiser involving what might be called pseudo-continuous acceleration appears to require that the bulk of the particle acceleration occurs in a very large Galactic halo, the secondaries being produced only in the gas disk. Problems are likely, however, with the expected fluxes of X-rays and radio synchrotron radiation

  2. Program Annual Technology Report: Cosmic Origins Program Office

    Science.gov (United States)

    Pham, Thai; Neff, Susan

    2017-01-01

    What is the Cosmic Origins (COR) Program? From ancient times, humans have looked up at the night sky and wondered: Are we alone? How did the universe come to be? How does the universe work? COR focuses on the second question. Scientists investigating this broad theme seek to understand the origin and evolution of the universe from the Big Bang to the present day, determining how the expanding universe grew into a grand cosmic web of dark matter enmeshed with galaxies and pristine gas, forming, merging, and evolving over time. COR also seeks to understand how stars and planets form from clouds in these galaxies to create the heavy elements that are essential to life, starting with the first generation of stars to seed the universe, and continuing through the birth and eventual death of all subsequent generations of stars. The COR Programs purview includes the majority of the field known as astronomy.

  3. Shocked molecular gas and the origin of cosmic rays

    Science.gov (United States)

    Reach, William; Gusdorf, Antoine; Richter, Matthew

    2018-06-01

    When massive stars reach the end of their ability to remain stable with core nuclear fusion, they explode in supernovae that drive powerful shocks into their surroundings. Because massive stars form in and remain close to molecular clouds they often drive shocks into dense gas, which is now believed to be the origin of a significant fraction of galactic cosmic rays. The nature of the supernova-molecular cloud interaction is not well understood, though observations are gradually elucidating their nature. The range of interstellar densities, and the inclusion of circumstellar matter from the late-phase mass-loss of the stars before their explosions, leads to a wide range of possible appearances and outcomes. In particular, it is not even clear what speed or physical type of shocks are present: are they dense, magnetically-mediated shocks where H2 is not dissociated, or are they faster shocks that dissociate molecules and destroy some of the grains? SOFIA is observing some of the most significant (in terms of cosmic ray production potential and infrared energy output) supernova-molecular cloud interactions for measurement of the line widths of key molecular shocks tracers: H2, [OI], and CO. The presence of gas at speeds 100 km/s or greater would indicate dissociative shocks, while speeds 30 km/s and slower retain most molecules. The shock velocity is a key ingredient in modeling the interaction between supernovae and molecular clouds including the potential for formation of cosmic rays.

  4. ORIGIN: Metal Creation and Evolution from the Cosmic Dawn

    CERN Document Server

    Herder, Jan-Willem den; Ohashi, Takaya; Kouveliotou, Chryssa; Hartmann, Dieter H.; Kaastra, Jelle S.; Amati, L.; Andersen, M.I.; Arnaud, M.; Attéia, J.-L.; Bandler, S.; Barbera, M.; Barcons, X.; Barthelmy, S.; Basa, S.; Basso, S.; Boer, M.; Branchini, E.; Branduardi-Raymont, G.; Borgani, S.; Boyarsky, A.; Brunetti, G.; Budtz-Jorgensen, C.; Burrows, D.; Butler, N.; Campana, S.; Caroli, E.; Ceballos, M.; Christensen, F.; Churazov, E.; Comastri, A.; Colasanti, L.; Cole, R.; Content, R.; Corsi, A.; Costantini, E.; Conconi, P.; Cusumano, G.; de Plaa, J.; De Rosa, A.; Del Santo, M.; Di Cosimo, S.; De Pasquale, M.; Doriese, R.; Ettori, S.; Evans, P.; Ezoe, Y.; Ferrari, L.; Finger, H.; Figueroa-Feliciano, T.; Friedrich, P.; Fujimoto, R.; Furuzawa, A.; Fynbo, J.; Gatti, F.; Galeazzi, M.; Gehrels, N.; Gendre, B.; Ghirlanda, G.; Ghisellini, G.; Gilfanov, M.; Giommi, P.; Girardi, M.; Grindlay, J.; Cocchi, M.; Godet, O.; Guedel, M.; Haardt, F.; den Hartog, R.; Hepburn, I.; Hermsen, W.; Hjorth, J.; Hoekstra, H.; Holland, A.; Hornstrup, A.; van der Horst, A.; Hoshino, A.; in 't Zand, J.; Irwin, K.; Ishisaki, Y.; Jonker, P.; Kitayama, T.; Kawahara, H.; Kawai, N.; Kelley, R.; Kilbourne, C.; de Korte, P.; Kusenko, A.; Kuvvetli, I.; Labanti, M.; Macculi, C.; Maiolino, R.; Hesse, M. Mas; Matsushita, K.; Mazzotta, P.; McCammon, D.; Méndez, M.; Mignani, R.; Mineo, T.; Mitsuda, K.; Mushotzky, R.; Molendi, S.; Moscardini, L.; Natalucci, L.; Nicastro, F.; O'Brien, P.; Osborne, J.; Paerels, F.; Page, M.; Paltani, S.; Pedersen, K.; Perinati, E.; Ponman, T.; Pointecouteau, E.; Predehl, P.; Porter, S.; Rasmussen, A.; Rauw, G.; Röttgering, H.; Roncarelli, M.; Rosati, P.; Quadrini, E.; Ruchayskiy, O.; Salvaterra, R.; Sasaki, S.; Sato, K.; Savaglio, S.; Schaye, J.; Sciortino, S.; Shaposhnikov, M.; Sharples, R.; Shinozaki, K.; Spiga, D.; Sunyaev, R.; Suto, Y.; Takei, Y.; Tanvir, N.; Tashiro, M.; Tamura, T.; Tawara, Y.; Troja, E.; Tsujimoto, M.; Tsuru, T.; Ubertini, P.; Ullom, J.; Ursino, E.; Verbunt, F.; van de Voort, F.; Viel, M.; Wachter, S.; Watson, D.; Weisskopf, M.; Werner, N.; White, N.; Willingale, R.; Wijers, R.; Yamasaki, N.; Yoshikawa, K.; Zane, S.

    2011-01-01

    ORIGIN is a proposal for the M3 mission call of ESA aimed at the study of metal creation from the epoch of cosmic dawn. Using high-spectral resolution in the soft X-ray band, ORIGIN will be able to identify the physical conditions of all abundant elements between C and Ni to red-shifts of z=10, and beyond. The mission will answer questions such as: When were the first metals created? How does the cosmic metal content evolve? Where do most of the metals reside in the Universe? What is the role of metals in structure formation and evolution? To reach out to the early Universe ORIGIN will use Gamma-Ray Bursts (GRBs) to study their local environments in their host galaxies. This requires the capability to slew the satellite in less than a minute to the GRB location. By studying the chemical composition and properties of clusters of galaxies we can extend the range of exploration to lower redshifts (z ~ 0.2). For this task we need a high-resolution spectral imaging instrument with a large field of view. Using the ...

  5. Exploring cosmic origins with CORE: Effects of observer peculiar motion

    Science.gov (United States)

    Burigana, C.; Carvalho, C. S.; Trombetti, T.; Notari, A.; Quartin, M.; Gasperis, G. D.; Buzzelli, A.; Vittorio, N.; De Zotti, G.; de Bernardis, P.; Chluba, J.; Bilicki, M.; Danese, L.; Delabrouille, J.; Toffolatti, L.; Lapi, A.; Negrello, M.; Mazzotta, P.; Scott, D.; Contreras, D.; Achúcarro, A.; Ade, P.; Allison, R.; Ashdown, M.; Ballardini, M.; Banday, A. J.; Banerji, R.; Bartlett, J.; Bartolo, N.; Basak, S.; Bersanelli, M.; Bonaldi, A.; Bonato, M.; Borrill, J.; Bouchet, F.; Boulanger, F.; Brinckmann, T.; Bucher, M.; Cabella, P.; Cai, Z.-Y.; Calvo, M.; Castellano, M. G.; Challinor, A.; Clesse, S.; Colantoni, I.; Coppolecchia, A.; Crook, M.; D'Alessandro, G.; Diego, J.-M.; Di Marco, A.; Di Valentino, E.; Errard, J.; Feeney, S.; Fernández-Cobos, R.; Ferraro, S.; Finelli, F.; Forastieri, F.; Galli, S.; Génova-Santos, R.; Gerbino, M.; González-Nuevo, J.; Grandis, S.; Greenslade, J.; Hagstotz, S.; Hanany, S.; Handley, W.; Hernández-Monteagudo, C.; Hervias-Caimapo, C.; Hills, M.; Hivon, E.; Kiiveri, K.; Kisner, T.; Kitching, T.; Kunz, M.; Kurki-Suonio, H.; Lamagna, L.; Lasenby, A.; Lattanzi, M.; Lesgourgues, J.; Liguori, M.; Lindholm, V.; Lopez-Caniego, M.; Luzzi, G.; Maffei, B.; Mandolesi, N.; Martinez-Gonzalez, E.; Martins, C. J. A. P.; Masi, S.; Matarrese, S.; McCarthy, D.; Melchiorri, A.; Melin, J.-B.; Molinari, D.; Monfardini, A.; Natoli, P.; Paiella, A.; Paoletti, D.; Patanchon, G.; Piat, M.; Pisano, G.; Polastri, L.; Polenta, G.; Pollo, A.; Poulin, V.; Remazeilles, M.; Roman, M.; Rubiño-Martín, J.-A.; Salvati, L.; Tartari, A.; Tomasi, M.; Tramonte, D.; Trappe, N.; Tucker, C.; Väliviita, J.; Van de Weijgaert, R.; van Tent, B.; Vennin, V.; Vielva, P.; Young, K.; Zannoni, M.

    2018-04-01

    We discuss the effects on the cosmic microwave background (CMB), cosmic infrared background (CIB), and thermal Sunyaev-Zeldovich effect due to the peculiar motion of an observer with respect to the CMB rest frame, which induces boosting effects. After a brief review of the current observational and theoretical status, we investigate the scientific perspectives opened by future CMB space missions, focussing on the Cosmic Origins Explorer (CORE) proposal. The improvements in sensitivity offered by a mission like CORE, together with its high resolution over a wide frequency range, will provide a more accurate estimate of the CMB dipole. The extension of boosting effects to polarization and cross-correlations will enable a more robust determination of purely velocity-driven effects that are not degenerate with the intrinsic CMB dipole, allowing us to achieve an overall signal-to-noise ratio of 13; this improves on the Planck detection and essentially equals that of an ideal cosmic-variance-limited experiment up to a multipole lsimeq2000. Precise inter-frequency calibration will offer the opportunity to constrain or even detect CMB spectral distortions, particularly from the cosmological reionization epoch, because of the frequency dependence of the dipole spectrum, without resorting to precise absolute calibration. The expected improvement with respect to COBE-FIRAS in the recovery of distortion parameters (which could in principle be a factor of several hundred for an ideal experiment with the CORE configuration) ranges from a factor of several up to about 50, depending on the quality of foreground removal and relative calibration. Even in the case of simeq1 % accuracy in both foreground removal and relative calibration at an angular scale of 1o, we find that dipole analyses for a mission like CORE will be able to improve the recovery of the CIB spectrum amplitude by a factor simeq 17 in comparison with current results based on COBE-FIRAS. In addition to the

  6. ORIGIN: Metal Creation and Evolution from the Cosmic Dawn

    Science.gov (United States)

    Kouveliotou, C.; vanderHorst, A.; Weisskopf, M.; White, N.; denHerder, J. W.; Costantini, E.; denHartog, R.; Hermsen, W.; in'tZhand, J.; Kaastra, J.; hide

    2012-01-01

    ORIGIN is a proposal for the M3 mission call of ESA aimed at the study of metal creation from the epoch of cosmic dawn. Using high-spectral resolution in the soft X-ray band, ORIGIN will be able to identify the physical conditions of all abundant elements between C and Ni to red-shifts of z=10, and beyond. The mission will answer questions such as: When were the first metals created? How does the cosmic metal content evolve? Where do most of the metals reside in the Universe? What is the role of metals in structure formation and evolution? To reach out to the early Universe ORIGIN will use Gamma-Ray Bursts (GRBs) to study their local environments in their host galaxies. This requires the capability to slew the satellite in less than a minute to the GRB location. By studying the chemical composition and properties of clusters of galaxies we can extend the range of exploration to lower redshifts (z approx. 0.2). For this task we need a high-resolution spectral imaging instrument with a large field of view. Using the same instrument, we can also study the so far only partially detected baryons in the Warm-Hot Intergalactic Medium (WHIM). The less dense part of the WHIM will be studied using absorption lines at low redshift in the spectra for GRBs. The ORIGIN mission includes a Transient Event Detector (coded mask with a sensitivity of 0.4 photon/sq cm/s in 10 s in the 5-150 keV band) to identify and localize 2000 GRBs over a five year mission, of which approx.65 GRBs have a redshift >7. The Cryogenic Imaging Spectrometer, with a spectral resolution of 2.5 eV, a field of view of 30 arcmin and large effective area below 1 keV has the sensitivity to study clusters up to a significant fraction of the virial radius and to map the denser parts of the WHIM (factor 30 higher than achievable with current instruments). The payload is complemented by a Burst InfraRed Telescope to enable onboard red-shift determination of GRBs (hence securing proper follow up of high-z bursts

  7. Exploring cosmic origins with CORE: Survey requirements and mission design

    Science.gov (United States)

    Delabrouille, J.; de Bernardis, P.; Bouchet, F. R.; Achúcarro, A.; Ade, P. A. R.; Allison, R.; Arroja, F.; Artal, E.; Ashdown, M.; Baccigalupi, C.; Ballardini, M.; Banday, A. J.; Banerji, R.; Barbosa, D.; Bartlett, J.; Bartolo, N.; Basak, S.; Baselmans, J. J. A.; Basu, K.; Battistelli, E. S.; Battye, R.; Baumann, D.; Benoít, A.; Bersanelli, M.; Bideaud, A.; Biesiada, M.; Bilicki, M.; Bonaldi, A.; Bonato, M.; Borrill, J.; Boulanger, F.; Brinckmann, T.; Brown, M. L.; Bucher, M.; Burigana, C.; Buzzelli, A.; Cabass, G.; Cai, Z.-Y.; Calvo, M.; Caputo, A.; Carvalho, C.-S.; Casas, F. J.; Castellano, G.; Catalano, A.; Challinor, A.; Charles, I.; Chluba, J.; Clements, D. L.; Clesse, S.; Colafrancesco, S.; Colantoni, I.; Contreras, D.; Coppolecchia, A.; Crook, M.; D'Alessandro, G.; D'Amico, G.; da Silva, A.; de Avillez, M.; de Gasperis, G.; De Petris, M.; de Zotti, G.; Danese, L.; Désert, F.-X.; Desjacques, V.; Di Valentino, E.; Dickinson, C.; Diego, J. M.; Doyle, S.; Durrer, R.; Dvorkin, C.; Eriksen, H. K.; Errard, J.; Feeney, S.; Fernández-Cobos, R.; Finelli, F.; Forastieri, F.; Franceschet, C.; Fuskeland, U.; Galli, S.; Génova-Santos, R. T.; Gerbino, M.; Giusarma, E.; Gomez, A.; González-Nuevo, J.; Grandis, S.; Greenslade, J.; Goupy, J.; Hagstotz, S.; Hanany, S.; Handley, W.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Hervias-Caimapo, C.; Hills, M.; Hindmarsh, M.; Hivon, E.; Hoang, D. T.; Hooper, D. C.; Hu, B.; Keihänen, E.; Keskitalo, R.; Kiiveri, K.; Kisner, T.; Kitching, T.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lamagna, L.; Lapi, A.; Lasenby, A.; Lattanzi, M.; Le Brun, A. M. C.; Lesgourgues, J.; Liguori, M.; Lindholm, V.; Lizarraga, J.; Luzzi, G.; Macìas-P{érez, J. F.; Maffei, B.; Mandolesi, N.; Martin, S.; Martinez-Gonzalez, E.; Martins, C. J. A. P.; Masi, S.; Massardi, M.; Matarrese, S.; Mazzotta, P.; McCarthy, D.; Melchiorri, A.; Melin, J.-B.; Mennella, A.; Mohr, J.; Molinari, D.; Monfardini, A.; Montier, L.; Natoli, P.; Negrello, M.; Notari, A.; Noviello, F.; Oppizzi, F.; O'Sullivan, C.; Pagano, L.; Paiella, A.; Pajer, E.; Paoletti, D.; Paradiso, S.; Partridge, R. B.; Patanchon, G.; Patil, S. P.; Perdereau, O.; Piacentini, F.; Piat, M.; Pisano, G.; Polastri, L.; Polenta, G.; Pollo, A.; Ponthieu, N.; Poulin, V.; Prêle, D.; Quartin, M.; Ravenni, A.; Remazeilles, M.; Renzi, A.; Ringeval, C.; Roest, D.; Roman, M.; Roukema, B. F.; Rubiño-Martin, J.-A.; Salvati, L.; Scott, D.; Serjeant, S.; Signorelli, G.; Starobinsky, A. A.; Sunyaev, R.; Tan, C. Y.; Tartari, A.; Tasinato, G.; Toffolatti, L.; Tomasi, M.; Torrado, J.; Tramonte, D.; Trappe, N.; Triqueneaux, S.; Tristram, M.; Trombetti, T.; Tucci, M.; Tucker, C.; Urrestilla, J.; Väliviita, J.; Van de Weygaert, R.; Van Tent, B.; Vennin, V.; Verde, L.; Vermeulen, G.; Vielva, P.; Vittorio, N.; Voisin, F.; Wallis, C.; Wandelt, B.; Wehus, I. K.; Weller, J.; Young, K.; Zannoni, M.

    2018-04-01

    Future observations of cosmic microwave background (CMB) polarisation have the potential to answer some of the most fundamental questions of modern physics and cosmology, including: what physical process gave birth to the Universe we see today? What are the dark matter and dark energy that seem to constitute 95% of the energy density of the Universe? Do we need extensions to the standard model of particle physics and fundamental interactions? Is the ΛCDM cosmological scenario correct, or are we missing an essential piece of the puzzle? In this paper, we list the requirements for a future CMB polarisation survey addressing these scientific objectives, and discuss the design drivers of the COREmfive space mission proposed to ESA in answer to the "M5" call for a medium-sized mission. The rationale and options, and the methodologies used to assess the mission's performance, are of interest to other future CMB mission design studies. COREmfive has 19 frequency channels, distributed over a broad frequency range, spanning the 60–600 GHz interval, to control astrophysical foreground emission. The angular resolution ranges from 2' to 18', and the aggregate CMB sensitivity is about 2 μKṡarcmin. The observations are made with a single integrated focal-plane instrument, consisting of an array of 2100 cryogenically-cooled, linearly-polarised detectors at the focus of a 1.2-m aperture cross-Dragone telescope. The mission is designed to minimise all sources of systematic effects, which must be controlled so that no more than 10‑4 of the intensity leaks into polarisation maps, and no more than about 1% of E-type polarisation leaks into B-type modes. COREmfive observes the sky from a large Lissajous orbit around the Sun-Earth L2 point on an orbit that offers stable observing conditions and avoids contamination from sidelobe pick-up of stray radiation originating from the Sun, Earth, and Moon. The entire sky is observed repeatedly during four years of continuous scanning

  8. Stellar origin of the 22Ne excess in cosmic rays

    International Nuclear Information System (INIS)

    Casse, M.; Paul, J.A.

    1982-01-01

    The 22 Ne excess at the cosmic-ray source is discussed in terms of a 22 Ne-rich component injected and accelerated by carbon-rich Wolf-Rayet stars. The overabundance of 22 Ne relative to 20 Ne predicted at the surface of these stars is estimated to a factor approx.120 with respect to solar system abundances. In order to give rise to a 22 Ne excess of about 3 at the cosmic-ray sources as inferred from observations, the carbon-rich Wolf-Rayet contribution to the primary cosmic-ray flux is to be at maximum 1/60. This component would be energized by strong stellar winds producing quasi-standing shocks around the Wolf-Rayet stars

  9. The origins of cosmic rays and quantum effects on gravity

    Science.gov (United States)

    Tomozawa, Y.

    1985-01-01

    The energy spectrum of primary cosmic rays is explained by particles emitted during a thermal expansion of explosive objects inside and near the galaxy, remnants of which may be supernova and/or active talaxies, or even stars or galaxies that disappeared from our sight after the explosion. A power law energy spectrum for cosmic rays, E to the (-alpha -1, is obtained from an expansion rate T is proportional to R to the alpha. Using the solution of the Einstein equation, we obtain a spectrum which agrees very well with experimental data. The implication of an inflationary early universe on the cosmic ray spectrum is also discussed. It is also suggested that the conflict between this model and the singularity theorem in classical general relativity may be eliminated by quantum effects.

  10. Cosmic gamma radiation of ultra high energy of primordial origin

    International Nuclear Information System (INIS)

    Aquino Filho, F.G. de.

    1984-01-01

    The quantum mechanical effects near a collapsing black hole as shown by Stephen W.Hawking in 1974 to produce streaming particles through tunneling effect was explored in the context of cosmic gamma ray production. In this thesis, we show the possible production of gamma rays of high energies (ν approx 10 41 Hz) in the initial stages of the formation of the Universe by the explosion of primordial mini black holes. These mini black hole explosions happening at 10 -43 s to 10 -37 s after the start perhaps may account for the existing universal cosmic background radiation of 2.7 0 K. (Author) [pt

  11. Spectrographic analysis

    International Nuclear Information System (INIS)

    Quinn, C.A.

    1983-01-01

    The article deals with spectrographic analysis and the analytical methods based on it. The theory of spectrographic analysis is discussed as well as the layout of a spectrometer system. The infrared absorption spectrum of a compound is probably its most unique property. The absorption of infrared radiation depends on increasing the energy of vibration and rotation associated with a covalent bond. The infrared region is intrinsically low in energy thus the design of infrared spectrometers is always directed toward maximising energy throughput. The article also considers atomic absorption - flame atomizers, non-flame atomizers and the source of radiation. Under the section an emission spectroscopy non-electrical energy sources, electrical energy sources and electrical flames are discussed. Digital computers form a part of the development on spectrographic instrumentation

  12. Supernova remnants and the origin of cosmic rays

    NARCIS (Netherlands)

    Vink, J.

    2014-01-01

    Supernova remnants have long been considered to be the dominant sources of Galactic cosmic rays. For a long time the prime evidence consisted of radio synchrotron radiation from supernova remnants, indicating the presence of electrons with energies of several GeV. However, in order to explain the

  13. On the Origin of Ultra High Energy Cosmic Rays II

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, T K; Colgate, S; Li, H; Bulmer, R H; Pino, J

    2011-03-08

    We show that accretion disks around Active Galactic Nuclei (AGNs) could account for the enormous power in observed ultra high energy cosmic rays {approx}10{sup 20} eV (UHEs). In our model, cosmic rays are produced by quasi-steady acceleration of ions in magnetic structures previously proposed to explain jets around Active Galactic Nuclei with supermassive black holes. Steady acceleration requires that an AGN accretion disk act as a dynamo, which we show to follow from a modified Standard Model in which the magnetic torque of the dynamo replaces viscosity as the dominant mechanism accounting for angular momentum conservation during accretion. A black hole of mass M{sub BH} produces a steady dynamo voltage V {proportional_to} {radical}M{sub BH} giving V {approx} 10{sup 20} volts for M{sub BH} {approx} 10{sup 8} solar masses. The voltage V reappears as an inductive electric field at the advancing nose of a dynamo-driven jet, where plasma instability inherent in collisionless runaway acceleration allows ions to be steadily accelerated to energies {approx} V, finally ejected as cosmic rays. Transient events can produce much higher energies. The predicted disk radiation is similar to the Standard Model. Unique predictions concern the remarkable collimation of jets and emissions from the jet/radiolobe structure. Given MBH and the accretion rate, the model makes 7 predictions roughly consistent with data: (1) the jet length; (2) the jet radius; (3) the steady-state cosmic ray energy spectrum; (4) the maximum energy in this spectrum; (5) the UHE cosmic ray intensity on Earth; (6) electron synchrotron wavelengths; and (7) the power in synchrotron radiation. These qualitative successes motivate new computer simulations, experiments and data analysis to provide a quantitative verification of the model.

  14. Regge in the sky: Origin of the cosmic rotation

    International Nuclear Information System (INIS)

    Muradian, R.

    1994-06-01

    Observed universal spin and mass relationship for a wide range of astronomical objects are described by two extended Regge trajectories: disc-trajectory for stars and planets, and ball-trajectory for galaxies and their clusters. The cosmic Chew-Frautschi plot is presented and two fundamental points are revealed on it: Eddington and Chandrasekhar points with coordinates expressed via combinations of the fundamental constants. (author). 17 refs, 3 figs

  15. Origin of the Cosmic Network: Nature vs Nurture

    OpenAIRE

    Shandarin, Sergei; Habib, Salman; Heitmann, Katrin

    2009-01-01

    The large-scale structure of the Universe, as traced by the distribution of galaxies, is now being revealed by large-volume cosmological surveys. The structure is characterized by galaxies distributed along filaments, the filaments connecting in turn to form a percolating network. Our objective here is to quantitatively specify the underlying mechanisms that drive the formation of the cosmic network: By combining percolation-based analyses with N-body simulations of gravitational structure fo...

  16. Next generation redshift surveys and the origin of cosmic acceleration

    International Nuclear Information System (INIS)

    Acquaviva, Viviana; Hajian, Amir; Spergel, David N.; Das, Sudeep

    2008-01-01

    Cosmologists are exploring two possible sets of explanations for the remarkable observation of cosmic acceleration: dark energy fills space or general relativity fails on cosmological scales. We define a null test parameter ε(k,a)≡Ω m -γ dlnD/dlna-1, where a is the scale factor, D is the growth rate of structure, Ω m (a) is the matter density parameter, and γ is a simple function of redshift. We show that it can be expressed entirely in terms of the bias factor, b(a), measured from cross correlations with cosmic microwave background (CMB) lensing, and the amplitude of redshift-space distortions, β(k,a). Measurements of the CMB power spectrum determine Ω m0 H 0 2 . If dark energy within general relativity is the solution to the cosmic acceleration problem, then the logarithmic growth rate of structure dlnD/dlna=Ω m γ . Thus, ε(k,a)=0 on linear scales to better than 1%. We show that in the class of modified gravity models known as f(R), the growth rate has a different dependence on scale and redshift. By combining measurements of the amplitude of β and of the bias, b, redshift surveys will be able to determine the logarithmic growth rate as a function of scale and redshift. We estimate the predicted sensitivity of the proposed SDSS III (BOSS) survey and the proposed ADEPT mission and find that they will test structure growth in general relativity to the percent level.

  17. Improved Emission Spectrographic Facility

    International Nuclear Information System (INIS)

    Goergen, C.R.; Lethco, A.J.; Hosken, G.B.; Geckeler, D.R.

    1980-10-01

    The Savannah River Plant's original Emission Spectrographic Laboratory for radioactive samples had been in operation for 25 years. Due to the deteriorated condition and the fire hazard posed by the wooden glove box trains, a project to update the facility was funded. The new laboratory improved efficiency of operation and incorporated numerous safety and contamination control features

  18. Cosmic Ray Origin: Lessons from Ultra-High-Energy Cosmic Rays and the Galactic/Extragalactic Transition

    Energy Technology Data Exchange (ETDEWEB)

    Parizot, Etienne

    2014-11-15

    We examine the question of the origin of the Galactic cosmic-rays (GCRs) in the light of the data available at the highest energy end of the spectrum. We argue that the data of the Pierre Auger Observatory and of the KASCADE-Grande experiment suggest that the transition between the Galactic and the extragalactic components takes place at the energy of the ankle in the all-particle cosmic-ray spectrum, and at an energy of the order of 10{sup 17} eV for protons. Such a high energy for Galactic protons appears difficult to reconcile with the general view that GCRs are accelerated by the standard diffusive shock acceleration process at the forward shock of individual supernova remnants (SNRs). We also review various difficulties of the standard SNR-GCR connection, related to the evolution of the light element abundances and to significant isotopic anomalies. We point out that most of the power injected by the supernovæ in the Galaxy is actually released inside superbubbles, which may thus play an important role in the origin of cosmic-rays, and could solve some persistent problems of the standard SNR-GCR scenario in a rather natural way.

  19. New look on the origin of cosmic rays

    Directory of Open Access Journals (Sweden)

    Istomin Ya.N.

    2017-01-01

    Full Text Available From the analysis of the flux of high energy particles, E > 3 · 1018 eV, it is shown that the distribution of the power density of extragalactic rays over energy is of the power law, q̅(E ∝ E−2.7, with the same index of 2.7 that has the distribution of Galactic cosmic rays before the so called ‘knee', E 3 · 1015 eV, from the Galaxy because of the dependence of the coefficient of diffusion of cosmic rays on energy, D∝E0.7. The obtained index of the density distribution of particles over energy, N(E∝E−2.7−0.7/2=E−3.05, for E > 3 · 1015 eV agrees well with the observed one, N(E∝E−3.1. The estimated time of the termination of the jet in the Galaxy is 4.2 · 104 years ago.

  20. Exploring cosmic origins with CORE: Gravitational lensing of the CMB

    Science.gov (United States)

    Challinor, A.; Allison, R.; Carron, J.; Errard, J.; Feeney, S.; Kitching, T.; Lesgourgues, J.; Lewis, A.; Zubeldía, Í.; Achucarro, A.; Ade, P.; Ashdown, M.; Ballardini, M.; Banday, A. J.; Banerji, R.; Bartlett, J.; Bartolo, N.; Basak, S.; Baumann, D.; Bersanelli, M.; Bonaldi, A.; Bonato, M.; Borrill, J.; Bouchet, F.; Boulanger, F.; Brinckmann, T.; Bucher, M.; Burigana, C.; Buzzelli, A.; Cai, Z.-Y.; Calvo, M.; Carvalho, C.-S.; Castellano, G.; Chluba, J.; Clesse, S.; Colantoni, I.; Coppolecchia, A.; Crook, M.; d'Alessandro, G.; de Bernardis, P.; de Gasperis, G.; De Zotti, G.; Delabrouille, J.; Di Valentino, E.; Diego, J.-M.; Fernandez-Cobos, R.; Ferraro, S.; Finelli, F.; Forastieri, F.; Galli, S.; Genova-Santos, R.; Gerbino, M.; González-Nuevo, J.; Grandis, S.; Greenslade, J.; Hagstotz, S.; Hanany, S.; Handley, W.; Hernandez-Monteagudo, C.; Hervías-Caimapo, C.; Hills, M.; Hivon, E.; Kiiveri, K.; Kisner, T.; Kunz, M.; Kurki-Suonio, H.; Lamagna, L.; Lasenby, A.; Lattanzi, M.; Liguori, M.; Lindholm, V.; López-Caniego, M.; Luzzi, G.; Maffei, B.; Martinez-González, E.; Martins, C. J. A. P.; Masi, S.; Matarrese, S.; McCarthy, D.; Melchiorri, A.; Melin, J.-B.; Molinari, D.; Monfardini, A.; Natoli, P.; Negrello, M.; Notari, A.; Paiella, A.; Paoletti, D.; Patanchon, G.; Piat, M.; Pisano, G.; Polastri, L.; Polenta, G.; Pollo, A.; Poulin, V.; Quartin, M.; Remazeilles, M.; Roman, M.; Rubino-Martin, J.-A.; Salvati, L.; Tartari, A.; Tomasi, M.; Tramonte, D.; Trappe, N.; Trombetti, T.; Tucker, C.; Valiviita, J.; Van de Weijgaert, R.; van Tent, B.; Vennin, V.; Vielva, P.; Vittorio, N.; Young, K.; Zannoni, M.

    2018-04-01

    Lensing of the cosmic microwave background (CMB) is now a well-developed probe of the clustering of the large-scale mass distribution over a broad range of redshifts. By exploiting the non-Gaussian imprints of lensing in the polarization of the CMB, the CORE mission will allow production of a clean map of the lensing deflections over nearly the full-sky. The number of high-S/N modes in this map will exceed current CMB lensing maps by a factor of 40, and the measurement will be sample-variance limited on all scales where linear theory is valid. Here, we summarise this mission product and discuss the science that will follow from its power spectrum and the cross-correlation with other clustering data. For example, the summed mass of neutrinos will be determined to an accuracy of 17 meV combining CORE lensing and CMB two-point information with contemporaneous measurements of the baryon acoustic oscillation feature in the clustering of galaxies, three times smaller than the minimum total mass allowed by neutrino oscillation measurements. Lensing has applications across many other science goals of CORE, including the search for B-mode polarization from primordial gravitational waves. Here, lens-induced B-modes will dominate over instrument noise, limiting constraints on the power spectrum amplitude of primordial gravitational waves. With lensing reconstructed by CORE, one can "delens" the observed polarization internally, reducing the lensing B-mode power by 60 %. This can be improved to 70 % by combining lensing and measurements of the cosmic infrared background from CORE, leading to an improvement of a factor of 2.5 in the error on the amplitude of primordial gravitational waves compared to no delensing (in the null hypothesis of no primordial B-modes). Lensing measurements from CORE will allow calibration of the halo masses of the tens of thousands of galaxy clusters that it will find, with constraints dominated by the clean polarization-based estimators. The 19

  1. Exploring cosmic origins with CORE: B-mode component separation

    Science.gov (United States)

    Remazeilles, M.; Banday, A. J.; Baccigalupi, C.; Basak, S.; Bonaldi, A.; De Zotti, G.; Delabrouille, J.; Dickinson, C.; Eriksen, H. K.; Errard, J.; Fernandez-Cobos, R.; Fuskeland, U.; Hervías-Caimapo, C.; López-Caniego, M.; Martinez-González, E.; Roman, M.; Vielva, P.; Wehus, I.; Achucarro, A.; Ade, P.; Allison, R.; Ashdown, M.; Ballardini, M.; Banerji, R.; Bartlett, J.; Bartolo, N.; Baumann, D.; Bersanelli, M.; Bonato, M.; Borrill, J.; Bouchet, F.; Boulanger, F.; Brinckmann, T.; Bucher, M.; Burigana, C.; Buzzelli, A.; Cai, Z.-Y.; Calvo, M.; Carvalho, C.-S.; Castellano, G.; Challinor, A.; Chluba, J.; Clesse, S.; Colantoni, I.; Coppolecchia, A.; Crook, M.; D'Alessandro, G.; de Bernardis, P.; de Gasperis, G.; Diego, J.-M.; Di Valentino, E.; Feeney, S.; Ferraro, S.; Finelli, F.; Forastieri, F.; Galli, S.; Genova-Santos, R.; Gerbino, M.; González-Nuevo, J.; Grandis, S.; Greenslade, J.; Hagstotz, S.; Hanany, S.; Handley, W.; Hernandez-Monteagudo, C.; Hills, M.; Hivon, E.; Kiiveri, K.; Kisner, T.; Kitching, T.; Kunz, M.; Kurki-Suonio, H.; Lamagna, L.; Lasenby, A.; Lattanzi, M.; Lesgourgues, J.; Lewis, A.; Liguori, M.; Lindholm, V.; Luzzi, G.; Maffei, B.; Martins, C. J. A. P.; Masi, S.; Matarrese, S.; McCarthy, D.; Melin, J.-B.; Melchiorri, A.; Molinari, D.; Monfardini, A.; Natoli, P.; Negrello, M.; Notari, A.; Paiella, A.; Paoletti, D.; Patanchon, G.; Piat, M.; Pisano, G.; Polastri, L.; Polenta, G.; Pollo, A.; Poulin, V.; Quartin, M.; Rubino-Martin, J.-A.; Salvati, L.; Tartari, A.; Tomasi, M.; Tramonte, D.; Trappe, N.; Trombetti, T.; Tucker, C.; Valiviita, J.; Van de Weijgaert, R.; van Tent, B.; Vennin, V.; Vittorio, N.; Young, K.; Zannoni, M.

    2018-04-01

    We demonstrate that, for the baseline design of the CORE satellite mission, the polarized foregrounds can be controlled at the level required to allow the detection of the primordial cosmic microwave background (CMB) B-mode polarization with the desired accuracy at both reionization and recombination scales, for tensor-to-scalar ratio values of rgtrsim 5× 10‑3. We consider detailed sky simulations based on state-of-the-art CMB observations that consist of CMB polarization with τ=0.055 and tensor-to-scalar values ranging from r=10‑2 to 10‑3, Galactic synchrotron, and thermal dust polarization with variable spectral indices over the sky, polarized anomalous microwave emission, polarized infrared and radio sources, and gravitational lensing effects. Using both parametric and blind approaches, we perform full component separation and likelihood analysis of the simulations, allowing us to quantify both uncertainties and biases on the reconstructed primordial B-modes. Under the assumption of perfect control of lensing effects, CORE would measure an unbiased estimate of r=(5 ± 0.4)× 10‑3 after foreground cleaning. In the presence of both gravitational lensing effects and astrophysical foregrounds, the significance of the detection is lowered, with CORE achieving a 4σ-measurement of r=5× 10‑3 after foreground cleaning and 60% delensing. For lower tensor-to-scalar ratios (r=10‑3) the overall uncertainty on r is dominated by foreground residuals, not by the 40% residual of lensing cosmic variance. Moreover, the residual contribution of unprocessed polarized point-sources can be the dominant foreground contamination to primordial B-modes at this r level, even on relatively large angular scales, l ~ 50. Finally, we report two sources of potential bias for the detection of the primordial B-modes by future CMB experiments: (i) the use of incorrect foreground models, e.g. a modelling error of Δβs = 0.02 on the synchrotron spectral indices may result in an

  2. Cosmic strings and the origin of structure in the universe

    International Nuclear Information System (INIS)

    Eardley, D.M.

    1987-01-01

    The observed universe is homogeneous and isotropic on the largest observable scales. The best evidence for this comes from observations of the cosmic background radiation (CBR). On smaller scales, a striking amount of structure can be seen - galaxies, clusters of galaxies, and the large scale structure in the form of possible filaments, bubbles, sheets or voids. The best proximate explanation for this structure is small amplitude perturbations in the early universe, which grew by gravitational instability into the observed large scale structure during the expansion of the universe. At some time in the future when we have a complete theory of the universe and its initial conditions - see James Hartle's lectures in this volume for some promising ideas toward such a theory - both the overall homogeneity and the structure should be a calculable consequence of the theory. Until then, people have made partial progress toward understanding the genesis of structure on a homogeneous background, based on the laws of fundamental physics as currently known. At this time we have at least two possible fundamental mechanisms for generation of the conjectural initial perturbations, namely quantum fluctuations, or thermodynamic fluctuations of a particular sort. The authors purpose in these lectures is to review and outline the basic physical nature of these two mechanisms, leaving out the details. Both mechanisms are well reviewed in the literature, and the reader will be referred both to more comprehensive reviews and to the primary literature throughout these lectures. 35 references, 2 tables

  3. Stellar black holes and the origin of cosmic acceleration

    International Nuclear Information System (INIS)

    Prescod-Weinstein, Chanda; Afshordi, Niayesh; Balogh, Michael L.

    2009-01-01

    The discovery of cosmic acceleration has presented a unique challenge for cosmologists. As observational cosmology forges ahead, theorists have struggled to make sense of a standard model that requires extreme fine-tuning. This challenge is known as the cosmological constant problem. The theory of gravitational aether is an alternative to general relativity that does not suffer from this fine-tuning problem, as it decouples the quantum field theory vacuum from geometry, while remaining consistent with other tests of gravity. In this paper, we study static black hole solutions in this theory and show that it manifests a UV-IR coupling: Aether couples the space-time metric close to the black hole horizon, to metric at infinity. We then show that using the trans-Planckian ansatz (as a quantum gravity effect) close to the black hole horizon, leads to an accelerating cosmological solution, far from the horizon. Interestingly, this acceleration matches current observations for stellar-mass black holes. Based on our current understanding of the black hole accretion history in the Universe, we then make a prediction for how the effective dark energy density should evolve with redshift, which can be tested with future dark energy probes.

  4. Origin of the cosmic x-ray background

    International Nuclear Information System (INIS)

    Margon, B.

    1983-01-01

    Since 1962, it has been known that every part of the sky emits a uniform glow of x-rays. After two decades of intense study the origin of this diffuse x-ray background is still a subject of controversy. The near perfect isotropy of the x-ray background is clearly a vital clue to its origin. A second clue to the origin of the x-ray background arises from the fact that it is x-radiation tha is generated, rather than some longer wavelength radiation. Two hypotheses of the origin of this x-ray background are discussed. One hypothesis is that the x-ray background can be attributed to bremsstrahlung from a hot intergalactic medium. The second hypothesis is that the x-ray background originates from a large number of quasars. Because there is no estimate independent of the intensity of the x-ray background of how much hot intergalactic medium exists (if any), there is a real possibility that both sources contribute to the observed x-rays. (SC)

  5. NASA's Chandra Reveals Origin of Key Cosmic Explosions

    Science.gov (United States)

    2010-02-01

    WASHINGTON -- New findings from NASA's Chandra X-ray Observatory have provided a major advance in understanding a type of supernova critical for studying the dark energy that astronomers think pervades the universe. The results show mergers of two dense stellar remnants are the likely cause of many of the supernovae that have been used to measure the accelerated expansion of the universe. These supernovae, called Type Ia, serve as cosmic mile markers to measure expansion of the universe because they can be seen at large distances, and they follow a reliable pattern of brightness. However, until now, scientists have been unsure what actually causes the explosions. "These are such critical objects in understanding the universe," said Marat Gilfanov of the Max Planck Institute for Astrophysics in Germany and lead author of the study that appears in the Feb. 18 edition of the journal Nature. "It was a major embarrassment that we did not know how they worked. Now we are beginning to understand what lights the fuse of these explosions." Most scientists agree a Type Ia supernova occurs when a white dwarf star -- a collapsed remnant of an elderly star -- exceeds its weight limit, becomes unstable and explodes. Scientists have identified two main possibilities for pushing the white dwarf over the edge: two white dwarfs merging or accretion, a process in which the white dwarf pulls material from a sun-like companion star until it exceeds its weight limit. "Our results suggest the supernovae in the galaxies we studied almost all come from two white dwarfs merging," said co-author Akos Bogdan, also of Max Planck. "This is probably not what many astronomers would expect." The difference between these two scenarios may have implications for how these supernovae can be used as "standard candles" -- objects of a known brightness -- to track vast cosmic distances. Because white dwarfs can come in a range of masses, the merger of two could result in explosions that vary somewhat in

  6. The origin of the universe as revealed through the polarization of the cosmic microwave background

    NARCIS (Netherlands)

    Dodelson, S.; et al., [Unknown; Meerburg, P.

    2009-01-01

    Modern cosmology has sharpened questions posed for millennia about the origin of our cosmic habitat. The age-old questions have been transformed into two pressing issues primed for attack in the coming decade: How did the Universe begin? and what physical laws govern the Universe at the highest

  7. Exploring cosmic origins with CORE: Extragalactic sources in cosmic microwave background maps

    Science.gov (United States)

    De Zotti, G.; González-Nuevo, J.; Lopez-Caniego, M.; Negrello, M.; Greenslade, J.; Hernández-Monteagudo, C.; Delabrouille, J.; Cai, Z.-Y.; Bonato, M.; Achúcarro, A.; Ade, P.; Allison, R.; Ashdown, M.; Ballardini, M.; Banday, A. J.; Banerji, R.; Bartlett, J. G.; Bartolo, N.; Basak, S.; Bersanelli, M.; Biesiada, M.; Bilicki, M.; Bonaldi, A.; Bonavera, L.; Borrill, J.; Bouchet, F.; Boulanger, F.; Brinckmann, T.; Bucher, M.; Burigana, C.; Buzzelli, A.; Calvo, M.; Carvalho, C. S.; Castellano, M. G.; Challinor, A.; Chluba, J.; Clements, D. L.; Clesse, S.; Colafrancesco, S.; Colantoni, I.; Coppolecchia, A.; Crook, M.; D'Alessandro, G.; de Bernardis, P.; de Gasperis, G.; Diego, J. M.; Di Valentino, E.; Errard, J.; Feeney, S. M.; Fernández-Cobos, R.; Ferraro, S.; Finelli, F.; Forastieri, F.; Galli, S.; Génova-Santos, R. T.; Gerbino, M.; Grandis, S.; Hagstotz, S.; Hanany, S.; Handley, W.; Hervias-Caimapo, C.; Hills, M.; Hivon, E.; Kiiveri, K.; Kisner, T.; Kitching, T.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lamagna, L.; Lasenby, A.; Lattanzi, M.; Le Brun, A.; Lesgourgues, J.; Lewis, A.; Liguori, M.; Lindholm, V.; Luzzi, G.; Maffei, B.; Mandolesi, N.; Martinez-Gonzalez, E.; Martins, C. J. A. P.; Masi, S.; Massardi, M.; Matarrese, S.; McCarthy, D.; Melchiorri, A.; Melin, J.-B.; Molinari, D.; Monfardini, A.; Natoli, P.; Notari, A.; Paiella, A.; Paoletti, D.; Partridge, R. B.; Patanchon, G.; Piat, M.; Pisano, G.; Polastri, L.; Polenta, G.; Pollo, A.; Poulin, V.; Quartin, M.; Remazeilles, M.; Roman, M.; Rossi, G.; Roukema, B. F.; Rubiño-Martín, J.-A.; Salvati, L.; Scott, D.; Serjeant, S.; Tartari, A.; Toffolatti, L.; Tomasi, M.; Trappe, N.; Triqueneaux, S.; Trombetti, T.; Tucci, M.; Tucker, C.; Väliviita, J.; van de Weygaert, R.; Van Tent, B.; Vennin, V.; Vielva, P.; Vittorio, N.; Young, K.; Zannoni, M.

    2018-04-01

    We discuss the potential of a next generation space-borne Cosmic Microwave Background (CMB) experiment for studies of extragalactic sources. Our analysis has particular bearing on the definition of the future space project, CORE, that has been submitted in response to ESA's call for a Medium-size mission opportunity as the successor of the Planck satellite. Even though the effective telescope size will be somewhat smaller than that of Planck, CORE will have a considerably better angular resolution at its highest frequencies, since, in contrast with Planck, it will be diffraction limited at all frequencies. The improved resolution implies a considerable decrease of the source confusion, i.e. substantially fainter detection limits. In particular, CORE will detect thousands of strongly lensed high-z galaxies distributed over the full sky. The extreme brightness of these galaxies will make it possible to study them, via follow-up observations, in extraordinary detail. Also, the CORE resolution matches the typical sizes of high-z galaxy proto-clusters much better than the Planck resolution, resulting in a much higher detection efficiency; these objects will be caught in an evolutionary phase beyond the reach of surveys in other wavebands. Furthermore, CORE will provide unique information on the evolution of the star formation in virialized groups and clusters of galaxies up to the highest possible redshifts. Finally, thanks to its very high sensitivity, CORE will detect the polarized emission of thousands of radio sources and, for the first time, of dusty galaxies, at mm and sub-mm wavelengths, respectively.

  8. The origin of cosmic gamma-ray bursts

    International Nuclear Information System (INIS)

    Van den Bergh, S.

    1983-01-01

    The positions of 46 γ-ray burst sources on the sky are used to show that the majority of these objects either originate in very distant regions with redshifts > or approx. 30 000 km s -1 or within < or approx. 0.5β of the Sun; where β is the scale-height of the parent population perpendicular to the galactic disc. An origin of the majority of γ-ray bursts in the more distant parts of the galactic disc, the galactic nuclear bulge, the Virgo supercluster, in galaxies with msub(pg) < 18 and rich in Abell clusters of distance classes 0 to 4 is excluded by the data. (orig.)

  9. A common origin of all the species of high energy cosmic rays?

    CERN Document Server

    Dar, Arnon; Antoniou, Nikos; Dar, Arnon; Antoniou, Nikos

    2000-01-01

    The cosmic ray nuclei with energy above a few GeV, the cosmic ray electrons of energy above a few MeV and the diffuse gamma-ray background above a few MeV, could all predominantly originate from our galaxy {\\it and its halo}. The mechanism accelerating hadrons and electrons is the same, the electron spectrum is modulated by inverse Compton scattering on the microwave background radiation, and the $\\gamma$-rays are the resulting recoiling photons. The spectra calculated on this basis agree with observations.

  10. The origin of life in a cosmic context

    Science.gov (United States)

    Sagan, C.

    1974-01-01

    It is shown that there is at present no aspect of contemporary biology where the contingent can be distinguished from the necessary, or the evolutionary accident from the biological sine qua non; and no amount of terrestrial experimentation alone is likely to make such distinctions possible. Hence, biology suffers from a deadening parochialism, much like the physics of falling bodies before Newton showed that the same laws applied to the motion of apples in England and to the planets about the sun. The deparochialization of biology can only come in the same way and must therefore await the search for extraterrestrial life. It is in this sense that the significance of explorations of the planets and their satellites, asteroids, comets, and the interplanetary medium for the origin of life is assessed.

  11. New component of cosmic rays of unknown origin at a few MeV per nucleon

    International Nuclear Information System (INIS)

    Gloecker, G.

    1974-04-01

    Recently discovered anomalies in the abundances and energy spectra of quiet time, extraterrestrial hydrogen, helium, carbon, nitrogen, and oxygen require serious revisions of origin theories to account for this new component of cosmic radiation. Abnormally large O/C and N/C ratios, long term intensity variations with time, and radial gradient measurements indicate a nonsolar origin for these 2 to 30 MeV/nucleon particles. Ideas suggested to explain these measurements range from acceleration of galactic source material having an unusual composition to local acceleration of particles within the solar cavity. Observations are at present insufficient to choose between these alternate origin models. (U.S.)

  12. Track-etched detectors for the dosimetry of the radiation of cosmic origin

    International Nuclear Information System (INIS)

    Spurny, F.; Turek, K.

    2004-01-01

    Cosmic rays contribute to the exposure on the Earth's surface as well as in its surroundings. At the surface and/or at aviation altitudes, there are mostly secondary particles created through the cosmic rays interaction in the atmosphere, which contribute to this type of exposure. Onboard a spacecraft, the exposure comes mostly from primary cosmic rays. Track-etched detectors (TED) are able to characterise both these types of exposure. The contribution of neutrons, of cosmic origin, on the Earth's surface was studied at altitudes from few hundreds to 3000 m using TED in a moderator sphere. The results obtained are compared with other data on this type of natural radiation background. The results of studies performed onboard aircraft and/or spacecraft are presented afterwards. We used TED-based neutron dosemeter, as well as a spectrometer of linear energy transfer based on a chemically etched TED. The results of studies performed onboard aircraft, as well as spacecraft, are presented and discussed, including an attempt to estimate a neutron component onboard the spacecraft. It was found that they correlate with the results of other independent investigations. (authors)

  13. Search for Cosmic-Ray Antiproton Origins and for Cosmological Antimatter with BESS

    Science.gov (United States)

    Yamamoto, A.; Mitchell, J. W.; Yoshimura, K.; Abe, K.; Fuke, H.; Haino, S.; Hams, T.; Hasegawa, M.; Horikoshi, A.; Itazaki, A.; hide

    2011-01-01

    The balloon-borne experiment with a superconducting spectrometer (BESS) has performed cosmic-ray observations as a US-Japan cooperative space science program, and has provided fundamental data on cosmic rays to study elementary particle phenomena in the early Universe. The BESS experiment has measured the energy spectra of cosmic-ray antiprotons to investigate signatures of possible exotic origins such as dark matter candidates or primordial black holes. and searched for heavier antinuclei that might reach Earth from antimatter domains formed in the early Universe. The apex of the BESS program was reached with the Antarctic flight of BESS-Polar II, during the 2007- 2008 Austral Summer, that obtained over 4.7 billion cosmic-ray events from 24.5 days of observation. The flight took place at the expected solar minimum, when the sensitivity of the low-energy antiproton measurements to a primary source is greatest. Here, we report the scientific restults, focusing on the long-duration flights of BESS-Polar I (2004) and BESS-Polar II (2007-2008).

  14. Origin of the cosmic network in ΛCDM: Nature vs nurture

    International Nuclear Information System (INIS)

    Shandarin, Sergei; Habib, Salman; Heitmann, Katrin

    2010-01-01

    The large-scale structure of the Universe, as traced by the distribution of galaxies, is now being revealed by large-volume cosmological surveys. The structure is characterized by galaxies distributed along filaments, the filaments connecting in turn to form a percolating network. Our objective here is to quantitatively specify the underlying mechanisms that drive the formation of the cosmic network: By combining percolation-based analyses with N-body simulations of gravitational structure formation, we elucidate how the network has its origin in the properties of the initial density field (nature) and how its contrast is then amplified by the nonlinear mapping induced by the gravitational instability (nurture).

  15. Origin of the cosmic network in ΛCDM: Nature vs nurture

    Science.gov (United States)

    Shandarin, Sergei; Habib, Salman; Heitmann, Katrin

    2010-05-01

    The large-scale structure of the Universe, as traced by the distribution of galaxies, is now being revealed by large-volume cosmological surveys. The structure is characterized by galaxies distributed along filaments, the filaments connecting in turn to form a percolating network. Our objective here is to quantitatively specify the underlying mechanisms that drive the formation of the cosmic network: By combining percolation-based analyses with N-body simulations of gravitational structure formation, we elucidate how the network has its origin in the properties of the initial density field (nature) and how its contrast is then amplified by the nonlinear mapping induced by the gravitational instability (nurture).

  16. Experimental techniques for the detection of the high energy gamma rays of cosmic origin

    International Nuclear Information System (INIS)

    Dumitrescu, Gh.; Angelescu, T.; Radu, A.A.

    2002-01-01

    The observation of high energy gamma rays of cosmic origin in the early 90 by Volcano Ranch experiment opened a new direction of study in astrophysics. The very high energy and the very low flux of these gamma rays, posed numerous detection problems which in turn were the object of a very intense research activity. The present article tries to review the detection techniques for the high energy gamma rays of cosmic origin. In the 'Introduction' we summarize the specific problems involved in the detection of this type of radiation. 'Chapter 1' presents the classic technique based on the use of scintillation detectors. 'Chapter 2' includes the imaging atmospheric Cherenkov technique (IACT) and the sampling wavefront technique. 'Chapter 3' is dedicated to the detection of the atmospheric nitrogen. 'Chapter 4' describes issues related to the calibration of the detectors, the cross checking of the experimental data, the use of the Monte Carlo simulations and the use of the density observed at a distance of 600 m S(600), in order to estimate the primary energy. The characteristics of some future developments of the above presented techniques are included in the last chapter. (authors)

  17. Simulations of ultra-high energy cosmic rays in the local Universe and the origin of cosmic magnetic fields

    Science.gov (United States)

    Hackstein, S.; Vazza, F.; Brüggen, M.; Sorce, J. G.; Gottlöber, S.

    2018-04-01

    We simulate the propagation of cosmic rays at ultra-high energies, ≳1018 eV, in models of extragalactic magnetic fields in constrained simulations of the local Universe. We use constrained initial conditions with the cosmological magnetohydrodynamics code ENZO. The resulting models of the distribution of magnetic fields in the local Universe are used in the CRPROPA code to simulate the propagation of ultra-high energy cosmic rays. We investigate the impact of six different magneto-genesis scenarios, both primordial and astrophysical, on the propagation of cosmic rays over cosmological distances. Moreover, we study the influence of different source distributions around the Milky Way. Our study shows that different scenarios of magneto-genesis do not have a large impact on the anisotropy measurements of ultra-high energy cosmic rays. However, at high energies above the Greisen-Zatsepin-Kuzmin (GZK)-limit, there is anisotropy caused by the distribution of nearby sources, independent of the magnetic field model. This provides a chance to identify cosmic ray sources with future full-sky measurements and high number statistics at the highest energies. Finally, we compare our results to the dipole signal measured by the Pierre Auger Observatory. All our source models and magnetic field models could reproduce the observed dipole amplitude with a pure iron injection composition. Our results indicate that the dipole is observed due to clustering of secondary nuclei in direction of nearby sources of heavy nuclei. A light injection composition is disfavoured, since the increase in dipole angular power from 4 to 8 EeV is too slow compared to observation by the Pierre Auger Observatory.

  18. The Super-TIGER Instrument to Probe Galactic Cosmic Ray Origins

    Science.gov (United States)

    Mitchell, John W.; Binns, W. R.; Bose, R, G.; Braun, D. L.; Christian, E. R.; Daniels, W. M; DeNolfo, G. A.; Dowkontt, P. F.; Hahne, D. J.; Hams, T.; hide

    2011-01-01

    Super-TIGER (Super Trans-Iron Galactic Element Recorder) is under construction for the first of two planned Antarctic long-duration balloon flights in December 2012. This new instrument will measure the abundances of ultra-heavy elements (30Zn and heavier), with individual element resolution, to provide sensitive tests of the emerging model of cosmic-ray origins in OB associations and models of the mechanism for selection of nuclei for acceleration. Super-TIGER builds on the techniques of TIGER, which produced the first well-resolved measurements of elemental abundances of the elements 31Ga, 32Ge, and 34Se. Plastic scintillators together with acrylic and silica-aerogel Cherenkov detectors measure particle charge. Scintillating-fiber hodoscopes track particle trajectories. Super-TIGER has an active area of 5.4 sq m, divided into two independent modules. With reduced material thickness to decrease interactions, its effective geometry factor is approx.6.4 times larger than TIGER, allowing it to measure elements up to 42Mo with high statistical precision, and make exploratory measurements up to 56Ba. Super-TIGER will also accurately determine the energy spectra of the more abundant elements from l0Ne to 28Ni between 0.8 and 10 GeV/nucleon to test the hypothesis that microquasars or other sources could superpose spectral features. We will discuss the implications of Super-TIGER measurements for the study of cosmic-ray origins and will present the measurement technique, design, status, and expected performance, including numbers of events and resolution. Details of the hodoscopes, scintillators, and Cherenkov detectors will be given in other presentations at this conference.

  19. Probing the origin of cosmic-rays with extremely high energy neutrinos using the IceCube Observatory

    DEFF Research Database (Denmark)

    Aartsen, M.G.; Abbasi, R.; Ackermann, M.

    2013-01-01

    originate from cosmogenic neutrinos produced in the interactions of ultrahigh energy cosmic rays with ambient photons while propagating through intergalactic space. Exploiting IceCube’s large exposure for extremely high energy neutrinos and the lack of observed events above 100 PeV, we can rule out...

  20. Origin of Spectral Band Patterns in the Cosmic Unidentified Infrared Emission

    Science.gov (United States)

    Álvaro Galué, Héctor; Díaz Leines, Grisell

    2017-10-01

    The cosmic unidentified infrared emission (UIE) band phenomenon is generally considered as indicative of free-flying polycyclic aromatic hydrocarbon molecules in space. However, a coherent explanation of emission spectral band patterns depending on astrophysical source is yet to be resolved under this attribution. Meanwhile astronomers have restored the alternative origin as due to amorphous carbon particles, but assigning spectral patterns to specific structural elements of particles is equally challenging. Here we report a physical principle in which inclusion of nonplanar structural defects in aromatic core molecular structures (π domains) induces spectral patterns typical of the phenomenon. We show that defects in model π domains modulate the electronic-vibration coupling that activates the delocalized π -electron contribution to aromatic vibrational modes. The modulation naturally disperses C =C stretch modes in band patterns that readily resemble the UIE bands in the elusive 6 - 9 μ m range. The electron-vibration interaction mechanics governing the defect-induced band patterns underscores the importance of π delocalization in the emergence of UIE bands. We discuss the global UIE band regularity of this range as compatible with an emission from the delocalized s p2 phase, as π domains, confined in disordered carbon mixed-phase aggregates.

  1. Probing the Extragalactic Cosmic-Ray Origin with Gamma-Ray and Neutrino Backgrounds

    Energy Technology Data Exchange (ETDEWEB)

    Globus, Noemie; Piran, Tsvi [Racah Institute of Physics, The Hebrew University, 91904 Jerusalem (Israel); Allard, Denis; Parizot, Etienne [Laboratoire Astroparticule et Cosmologie, Université Paris Diderot/CNRS, 10 rue A. Domon et L. Duquet, F-75205 Paris Cedex 13 (France)

    2017-04-20

    GeV–TeV gamma-rays and PeV–EeV neutrino backgrounds provide a unique window on the nature of the ultra-high-energy cosmic rays (UHECRs). We discuss the implications of the recent Fermi -LAT data regarding the extragalactic gamma-ray background and related estimates of the contribution of point sources as well as IceCube neutrino data on the origin of the UHECRs. We calculate the diffuse flux of cosmogenic γ -rays and neutrinos produced by the UHECRs and derive constraints on the possible cosmological evolution of UHECR sources. In particular, we show that the mixed-composition scenario considered in Globus et al., which is in agreement with both (i) Auger measurements of the energy spectrum and composition up to the highest energies and (ii) the ankle-like feature in the light component detected by KASCADE-Grande, is compatible with both the Fermi -LAT measurements and with current IceCube limits. We also discuss the possibility for future experiments to detect associated cosmogenic neutrinos and further constrain the UHECR models, including possible subdominant UHECR proton sources.

  2. Technical aspects of the Space Telescope Imaging Spectrograph Repair (STIS-R)

    Science.gov (United States)

    Rinehart, S. A.; Domber, J.; Faulkner, T.; Gull, T.; Kimble, R.; Klappenberger, M.; Leckrone, D.; Niedner, M.; Proffitt, C.; Smith, H.; Woodgate, B.

    2008-07-01

    In August 2004, the Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS) ceased operation due to a failure of the 5V mechanism power converter in the Side 2 Low Voltage Power Supply (LVPS2). The failure precluded movement of any STIS mechanism and, because of the earlier (2001) loss of the Side 1 electronics chain, left the instrument shuttered and in safe mode after 7.5 years of science operations. A team was assembled to analyze the fault and to determine if STIS repair (STIS-R) was feasible. The team conclusively pinpointed the Side 2 failure to the 5V mechanism converter, and began studying EVA techniques for opening STIS during Servicing Mission 4 (SM4) to replace the failed LVPS2 board. The restoration of STIS functionality via surgical repair by astronauts has by now reached a mature and final design state, and will, along with a similar repair procedure for the Advanced Camera for Surveys (ACS), represent a first for Hubble servicing. STIS-R will restore full scientific functionality of the spectrograph on Side 2, while Side 1 will remain inoperative. Because of the high degree of complementarity between STIS and the new Cosmic Origins Spectrograph (COS, to be installed during SM4)), successful repair of the older spectrograph is an important scientific objective. In this presentation, we focus on the technical aspects associated with STIS-R.

  3. NASA's Physics of the Cosmos and Cosmic Origins programs manage Strategic Astrophysics Technology (SAT) development

    Science.gov (United States)

    Pham, Thai; Thronson, Harley; Seery, Bernard; Ganel, Opher

    2016-07-01

    The strategic astrophysics missions of the coming decades will help answer the questions "How did our universe begin and evolve?" "How did galaxies, stars, and planets come to be?" and "Are we alone?" Enabling these missions requires advances in key technologies far beyond the current state of the art. NASA's Physics of the Cosmos2 (PCOS), Cosmic Origins3 (COR), and Exoplanet Exploration Program4 (ExEP) Program Offices manage technology maturation projects funded through the Strategic Astrophysics Technology (SAT) program to accomplish such advances. The PCOS and COR Program Offices, residing at the NASA Goddard Space Flight Center (GSFC), were established in 2011, and serve as the implementation arm for the Astrophysics Division at NASA Headquarters. We present an overview of the Programs' technology development activities and the current technology investment portfolio of 23 technology advancements. We discuss the process for addressing community-provided technology gaps and Technology Management Board (TMB)-vetted prioritization and investment recommendations that inform the SAT program. The process improves the transparency and relevance of our technology investments, provides the community a voice in the process, and promotes targeted external technology investments by defining needs and identifying customers. The Programs' priorities are driven by strategic direction from the Astrophysics Division, which is informed by the National Research Council's (NRC) "New Worlds, New Horizons in Astronomy and Astrophysics" (NWNH) 2010 Decadal Survey report [1], the Astrophysics Implementation Plan (AIP) [2] as updated, and the Astrophysics Roadmap "Enduring Quests, Daring Visions" [3]. These priorities include technology development for missions to study dark energy, gravitational waves, X-ray and inflation probe science, and large far-infrared (IR) and ultraviolet (UV)/optical/IR telescopes to conduct imaging and spectroscopy studies. The SAT program is the

  4. NASA's Physics of the Cosmos and Cosmic Origins Technology Development Programs

    Science.gov (United States)

    Pham, Thai; Seery, Bernard; Ganel, Opher

    2016-01-01

    The strategic astrophysics missions of the coming decades will help answer the questions "How did our universe begin and evolve?" and "How did galaxies, stars, and planets come to be?" Enabling these missions requires advances in key technologies far beyond the current state of the art. NASA's Physics of the Cosmos (PCOS) and Cosmic Origins (COR) Program Offices manage technology maturation projects funded through the Strategic Astrophysics Technology (SAT) program to accomplish such advances. The PCOS and COR Program Offices, residing at the NASA Goddard Space Flight Center (GSFC), were established in 2011, and serve as the implementation arm for the Astrophysics Division at NASA Headquarters. We present an overview of the Programs' technology development activities and the current technology investment portfolio of 23 technology advancements. We discuss the process for addressing community-provided technology gaps and Technology Management Board (TMB)-vetted prioritization and investment recommendations that inform the SAT program. The process improves the transparency and relevance of our technology investments, provides the community a voice in the process, and promotes targeted external technology investments by defining needs and identifying customers. The Programs' priorities are driven by strategic direction from the Astrophysics Division, which is informed by the National Research Council's (NRC) "New Worlds, New Horizons in Astronomy and Astrophysics" (NWNH) 2010 Decadal Survey report [1], the Astrophysics Implementation Plan (AIP) [2] as updated, and the Astrophysics Roadmap "Enduring Quests, Daring Visions" [3]. These priorities include technology development for missions to study dark energy, gravitational waves, X-ray and inflation probe science, and large far-infrared (IR) and ultraviolet (UV)/optical/IR telescopes to conduct imaging and spectroscopy studies. The SAT program is the Astrophysics Division's main investment method to mature technologies

  5. THE MULTI-OBJECT, FIBER-FED SPECTROGRAPHS FOR THE SLOAN DIGITAL SKY SURVEY AND THE BARYON OSCILLATION SPECTROSCOPIC SURVEY

    International Nuclear Information System (INIS)

    Smee, Stephen A.; Barkhouser, Robert H.; Gunn, James E.; Carr, Michael A.; Lupton, Robert H.; Loomis, Craig; Uomoto, Alan; Roe, Natalie; Schlegel, David; Rockosi, Constance M.; Leger, French; Owen, Russell; Anderson, Lauren; Dawson, Kyle S.; Olmstead, Matthew D.; Brinkmann, Jon; Long, Dan; Honscheid, Klaus; Harding, Paul; Annis, James

    2013-01-01

    We present the design and performance of the multi-object fiber spectrographs for the Sloan Digital Sky Survey (SDSS) and their upgrade for the Baryon Oscillation Spectroscopic Survey (BOSS). Originally commissioned in Fall 1999 on the 2.5 m aperture Sloan Telescope at Apache Point Observatory, the spectrographs produced more than 1.5 million spectra for the SDSS and SDSS-II surveys, enabling a wide variety of Galactic and extra-galactic science including the first observation of baryon acoustic oscillations in 2005. The spectrographs were upgraded in 2009 and are currently in use for BOSS, the flagship survey of the third-generation SDSS-III project. BOSS will measure redshifts of 1.35 million massive galaxies to redshift 0.7 and Lyα absorption of 160,000 high redshift quasars over 10,000 deg 2 of sky, making percent level measurements of the absolute cosmic distance scale of the universe and placing tight constraints on the equation of state of dark energy. The twin multi-object fiber spectrographs utilize a simple optical layout with reflective collimators, gratings, all-refractive cameras, and state-of-the-art CCD detectors to produce hundreds of spectra simultaneously in two channels over a bandpass covering the near-ultraviolet to the near-infrared, with a resolving power R = λ/FWHM ∼ 2000. Building on proven heritage, the spectrographs were upgraded for BOSS with volume-phase holographic gratings and modern CCD detectors, improving the peak throughput by nearly a factor of two, extending the bandpass to cover 360 nm < λ < 1000 nm, and increasing the number of fibers from 640 to 1000 per exposure. In this paper we describe the original SDSS spectrograph design and the upgrades implemented for BOSS, and document the predicted and measured performances

  6. THE MULTI-OBJECT, FIBER-FED SPECTROGRAPHS FOR THE SLOAN DIGITAL SKY SURVEY AND THE BARYON OSCILLATION SPECTROSCOPIC SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Smee, Stephen A.; Barkhouser, Robert H. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States); Gunn, James E.; Carr, Michael A.; Lupton, Robert H.; Loomis, Craig [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Uomoto, Alan [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Roe, Natalie; Schlegel, David [Physics Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Rockosi, Constance M. [UC Observatories and Department of Astronomy and Astrophysics, University of California, Santa Cruz, 375 Interdisciplinary Sciences Building (ISB) Santa Cruz, CA 95064 (United States); Leger, French; Owen, Russell; Anderson, Lauren [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 09195 (United States); Dawson, Kyle S.; Olmstead, Matthew D. [Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 (United States); Brinkmann, Jon; Long, Dan [Apache Point Observatory, Sunspot, NM 88349 (United States); Honscheid, Klaus [Department of Physics and Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States); Harding, Paul [Department of Astronomy, Case Western Reserve University, Cleveland, OH 44106 (United States); Annis, James, E-mail: smee@pha.jhu.edu [Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, IL 60510 (United States); and others

    2013-08-01

    We present the design and performance of the multi-object fiber spectrographs for the Sloan Digital Sky Survey (SDSS) and their upgrade for the Baryon Oscillation Spectroscopic Survey (BOSS). Originally commissioned in Fall 1999 on the 2.5 m aperture Sloan Telescope at Apache Point Observatory, the spectrographs produced more than 1.5 million spectra for the SDSS and SDSS-II surveys, enabling a wide variety of Galactic and extra-galactic science including the first observation of baryon acoustic oscillations in 2005. The spectrographs were upgraded in 2009 and are currently in use for BOSS, the flagship survey of the third-generation SDSS-III project. BOSS will measure redshifts of 1.35 million massive galaxies to redshift 0.7 and Ly{alpha} absorption of 160,000 high redshift quasars over 10,000 deg{sup 2} of sky, making percent level measurements of the absolute cosmic distance scale of the universe and placing tight constraints on the equation of state of dark energy. The twin multi-object fiber spectrographs utilize a simple optical layout with reflective collimators, gratings, all-refractive cameras, and state-of-the-art CCD detectors to produce hundreds of spectra simultaneously in two channels over a bandpass covering the near-ultraviolet to the near-infrared, with a resolving power R = {lambda}/FWHM {approx} 2000. Building on proven heritage, the spectrographs were upgraded for BOSS with volume-phase holographic gratings and modern CCD detectors, improving the peak throughput by nearly a factor of two, extending the bandpass to cover 360 nm < {lambda} < 1000 nm, and increasing the number of fibers from 640 to 1000 per exposure. In this paper we describe the original SDSS spectrograph design and the upgrades implemented for BOSS, and document the predicted and measured performances.

  7. THE MULTI-OBJECT, FIBER-FED SPECTROGRAPHS FOR THE SLOAN DIGITAL SKY SURVEY AND THE BARYON OSCILLATION SPECTROSCOPIC SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Smee, Stephen A.; Gunn, James E.; Uomoto, Alan; Roe, Natalie; Schlegel, David; Rockosi, Constance M.; Carr, Michael A.; Leger, French; Dawson, Kyle S.; Olmstead, Matthew D.; Brinkmann, Jon; Owen, Russell; Barkhouser, Robert H.; Honscheid, Klaus; Harding, Paul; Long, Dan; Lupton, Robert H.; Loomis, Craig; Anderson, Lauren; Annis, James; Bernardi, Mariangela; Bhardwaj, Vaishali; Bizyaev, Dmitry; Bolton, Adam S.; Brewington, Howard; Briggs, John W.; Burles, Scott; Burns, James G.; Castander, Francisco Javier; Connolly, Andrew; Davenport, James R. A.; Ebelke, Garrett; Epps, Harland; Feldman, Paul D.; Friedman, Scott D.; Frieman, Joshua; Heckman, Timothy; Hull, Charles L.; Knapp, Gillian R.; Lawrence, David M.; Loveday, Jon; Mannery, Edward J.; Malanushenko, Elena; Malanushenko, Viktor; Merrelli, Aronne James; Muna, Demitri; Newman, Peter R.; Nichol, Robert C.; Oravetz, Daniel; Pan, Kaike; Pope, Adrian C.; Ricketts, Paul G.; Shelden, Alaina; Sandford, Dale; Siegmund, Walter; Simmons, Audrey; Smith, D. Shane; Snedden, Stephanie; Schneider, Donald P.; SubbaRao, Mark; Tremonti, Christy; Waddell, Patrick; York, Donald G.

    2013-07-12

    We present the design and performance of the multi-object fiber spectrographs for the Sloan Digital Sky Survey (SDSS) and their upgrade for the Baryon Oscillation Spectroscopic Survey (BOSS). Originally commissioned in Fall 1999 on the 2.5-m aperture Sloan Telescope at Apache Point Observatory, the spectrographs produced more than 1.5 million spectra for the SDSS and SDSS-II surveys, enabling a wide variety of Galactic and extra-galactic science including the first observation of baryon acoustic oscillations in 2005. The spectrographs were upgraded in 2009 and are currently in use for BOSS, the flagship survey of the third-generation SDSS-III project. BOSS will measure redshifts of 1.35 million massive galaxies to redshift 0.7 and Lyman-alpha absorption of 160,000 high redshift quasars over 10,000 square degrees of sky, making percent level measurements of the absolute cosmic distance scale of the Universe and placing tight constraints on the equation of state of dark energy. The twin multi-object fiber spectrographs utilize a simple optical layout with reflective collimators, gratings, all-refractive cameras, and state-of-the-art CCD detectors to produce hundreds of spectra simultaneously in two channels over a bandpass covering the near ultraviolet to the near infrared, with a resolving power R = \\lambda/FWHM ~ 2000. Building on proven heritage, the spectrographs were upgraded for BOSS with volume-phase holographic gratings and modern CCD detectors, improving the peak throughput by nearly a factor of two, extending the bandpass to cover 360 < \\lambda < 1000 nm, and increasing the number of fibers from 640 to 1000 per exposure. In this paper we describe the original SDSS spectrograph design and the upgrades implemented for BOSS, and document the predicted and measured performances.

  8. Traces of heavy and superheavy cosmic nuclei in olivins of extraterrestial origin

    International Nuclear Information System (INIS)

    Ignatova, R.; Taneva, T.

    1982-01-01

    The paths of traces of WH nuclei from cosmic rays have been measured in olivines from the meteorites Maryalakhti, Eagle Stein, Liposki khutor with radiation ages 175, 45 and 220 million years respectively. 3 cm 3 olivines of these meteorites have been examined and more than 500 traces of nuclei with Z(>=)90 have been found measured including 3 traces 1.5-1.8 times longer than the traces created by the uranium and thorium nuclei. These traces may be left by nuclei with Z(>=)110. The crystals were chosen from localizations situated at 2-7 cm, 8-9 cm and 10-12 cm from the outside atmospheric surface of the meteorite. The abundancy of the Z(>=)50 nuclei in gigantic cosmic rays, averaged for a period of ( =)110 in galactic cosmic rays. It is 1.4 x 10 -9 from that of the iron group nuclei. (authors)

  9. Cosmic radiation

    Energy Technology Data Exchange (ETDEWEB)

    Capdevielle, J N

    1984-01-01

    First, the different instruments and techniques of cosmic particle detection are presented. Then the passage of the cosmic particles through the atmosphere is studied: electrons, photons, muons. The collective behavior of the different categories is also studied, the electromagnetic cascade is distinguished from the hadron cascade. Through the principal physical properties of the radiation and the medium, the ''mean'' aspects of the radiation are then successively dealt with out of the atmosphere, at different altitudes until the sea level, then at great depths. A chapter is devoted to cosmic radiation of more than 10,000 GeV, studied separately. Then solar radiation in universe is studied through their propagation in solar system and their origin. At last, the cosmic radiation effects are studied in environment (cosmic biophysics) and some applications of cosmic radiation are presented.

  10. Studying the high energy cosmic radiation: contributions to its detection and to the exploration of its origin

    International Nuclear Information System (INIS)

    Lamanna, Giovanni

    2009-01-01

    The Astro-particle Physics is a discipline where scientists from both the astrophysics and the particle physics communities meets to investigate the Universe aiming to answer to fundamental questions in the field of physics, cosmology and astrophysics. The high energy astrophysics domain, which explores the extremes sources where the larger collective transfer of energy take place, studies the most energetic cosmic radiation as privileged messengers of the history of the Universe. My research path, summarized in this work, is made of personal contributions in the development of new detection technologies, in the data analysis, perspectives and phenomenological studies about the scientific purposes of large experiments: e.g. AMS, ANTARES, HESS, CTA, POLAR. My contributions are the results of research activities in coherence with two main scientific goals in the context of the astro-particle physics domain: - The implication of the high energy cosmic radiation measurement for the investigation on the nature and distribution of the dark matter; - The investigation of the origin of the galactic cosmic radiation for the understanding of the most energetic processes in the Universe. (author)

  11. Geneva University: Particle Acceleration in supernova remnants and its implications for the origin of galactic cosmic rays

    CERN Multimedia

    Université de Genève

    2012-01-01

    GENEVA UNIVERSITY École de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 Genève 4 Tél.: (022) 379 62 73 Fax: (022) 379 69 92 Wednesday 28 March 2012 SEMINAIRE DE PHYSIQUE CORPUSCULAIRE 11h15 - Science III, Auditoire 1S081 Particle Acceleration in supernova remnants and its implications for the origin of galactic cosmic rays Prof. Pasquale BLASI INAF, Arcetri Observatory, Firenze The process of cosmic ray energization in supernova remnant shocks is described by the theory of non linear diffusive shock acceleration (NLDSA). Such theory is able to describe the acceleration itself, the dynamical reaction of accelerated particles on the shock, and the crucial phenomenon of the magnetic field amplification, the very key to generate high energy cosmic rays. I will illustrate the basic aspects of this theoretical framework, as well as its successes and problems. I will then discuss the observations, in X-rays an...

  12. Track-etched detectors for the dosimetry of the radiation of cosmic origin

    Czech Academy of Sciences Publication Activity Database

    Spurný, František; Turek, Karel

    2004-01-01

    Roč. 109, č. 4 (2004), s. 375-381 ISSN 0144-8420 R&D Projects: GA AV ČR KSK4055109 Grant - others:EC project(XE) FIGM-CT2000-00068 Institutional research plan: CEZ:AV0Z1048901 Keywords : track-etched detectors * cosmic rays * aircraft Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.617, year: 2003

  13. The Bess Investigation of the Origin of Cosmic-ray Antiprotons and Search for Cosmological Antimatter

    Science.gov (United States)

    Mitchell, John; Yamamoto, Akira; Yoshimura, Koji; Makida, Yasuhiro; Matsuda, Shinya; Hasegawa, Masaya; Horikoshi, Atsushi; Tanaka,Ken-ichi; Suzuki, Junichi; Nishimura, Jun; hide

    2008-01-01

    The Balloon-borne Experiment with a Superconducting Spectrometer (BESS) collaboration has made precise measurements of the spectra of cosmic ray antiprotons and light nuclei and conducted a sensitive search for antinuclei. Ten BESS high-latitude flights, eight from Canada and two from Antarctica, span more than a Solar cycle between 1993 and 2007/2008. BESS measurements of low-energy antiprotons constrain candidate models for dark matter including the possible signature of primordial black hole evaporation. The stringent BESS measurements of antiprotons and the elemental and isotopic spectra of H and He provide strong constraints on models of cosmic-ray transport in the Galaxy and Solar System. BESS has also reported the first antideuterium upper limit. BESS employs a superconducting magnetic-rigity spectrometer with time-of-flight and aerogel Cherenkov detectors to identify incident particles by charge, charge sign, mass, and energy. The BESS-Polar long-duration instrument has reduced lower energy limit of 100 MeV (top of the atmosphere) to increase its sensitivity to possible primary antiproton sources. BESS-Polar II was rebuilt with extended magnet lifetime, improved detector and electronic performance, and greater data storage capacity. It was flown fro Antarctica December 2007-January 2008, recording about 4.6 bission events during 24.5 days at float altitude with the magnet on. During the flight the influence of a high-speed stream in the Solar wind was observed. Details of the BESS-Polar II instrument and flight performance are reported elsewhere at this conference. The successful BESS-Polar II flight at Solar minimum is especially important. Most cosmic-ray antiprotons are secondary products of nuclear interactions of primary cosmic-ray nuclei with the interstellar gas, giving a spectrum that peaks at about 2 GeV and falls rapidly to higher and lower energies. However, BESS data taken in the previous Solar minimum show a small excess over secondary

  14. The BESS Search for Cosmic-Ray Antiproton Origins and for Cosmological Antimatter

    Science.gov (United States)

    Mitchell, John; Yamamoto, Akira

    2009-01-01

    The apex of the Balloon-borne Experiment with a Superconducting Spectrometer (BESS) program was reached with the Antarctic flight of BESS-Polar II, during the 2007-2008 Austral Summer, that obtained 24.5 days of data on over 4.7 billion cosmic-ray events. The US-Japan BESS Collaboration uses elementary particle measurements to study the early Universe and provides fundamental data on the spectra of light cosmic-ray elements and isotopes. BESS measures the energy spectra of cosmic-ray antiprotons to investigate signatures of possible exotic sources, such as dark-matter candidates, and searches for heavier antinuclei that might reach Earth from antimatter domains formed during symmetry breaking processes in the early Universe. Since 1993, BESS has carried out eleven high-latitude balloon flights, two of long duration, that together have defined the study of antiprotons below about 4 GeV, provided standard references for light element and isotope spectra, and set the most sensitive limits on the existence of antideuterons and antihelium. The BESS-Polar II flight took place at Solar Minimum, when the sensitivity of the low-energy antiproton measurements to a primary source is greatest. The rich BESS-Polar II dataset more than doubles the combined data from all earlier BESS flights and has 10-20 times the statistics of BESS data from the previous Solar Minimum. Here, we summarize the scientific results of BESS program, focusing on the results obtained using data from the long-duration flights of BESS-Polar I (2004) and BESS-Polar II.

  15. Comment on AMS02 results support the secondary origin of cosmic ray positrons

    OpenAIRE

    Dado, Shlomo; Dar, Arnon

    2015-01-01

    We present a simple calculation of the flux of secondary positrons produced in the ISM that is based only on priors. Our calculated ISM flux agrees very well with that calculated with the elaborate GALPROP code. It confirms that secondary production of positrons in the ISM by the primary cosmic rays cannot explain the observed sub-TeV flux of CR positrons. Moreover, we show that once energy loss of positrons in source and in the ISM are included, secondary production inside the CR sources plu...

  16. High-energy cosmic ray nuclei from tidal disruption events: Origin, survival, and implications

    Science.gov (United States)

    Zhang, B. Theodore; Murase, Kohta; Oikonomou, Foteini; Li, Zhuo

    2017-09-01

    Tidal disruption events (TDEs) by supermassive or intermediate mass black holes have been suggested as candidate sources of ultrahigh-energy cosmic rays (UHECRs) and high-energy neutrinos. Motivated by the recent measurements from the Pierre Auger Observatory, which indicates a metal-rich cosmic-ray composition at ultrahigh energies, we investigate the fate of UHECR nuclei loaded in TDE jets. First, we consider the production and survival of UHECR nuclei at internal shocks, external forward and reverse shocks, and nonrelativistic winds. Based on the observations of Swift J 1644 +57 , we show that the UHECRs can survive for external reverse and forward shocks, and disk winds. On the other hand, UHECR nuclei are significantly disintegrated in internal shocks, although they could survive for low-luminosity TDE jets. Assuming that UHECR nuclei can survive, we consider implications of different composition models of TDEs. We find that the tidal disruption of main sequence stars or carbon-oxygen white dwarfs does not successfully reproduce UHECR observations, namely the observed composition or spectrum. The observed mean depth of the shower maximum and its deviation could be explained by oxygen-neon-magnesium white dwarfs, although they may be too rare to be the sources of UHECRs.

  17. New investigations on the origin of cosmic rays. 1. Hess experiment

    International Nuclear Information System (INIS)

    Degrange, B.

    2005-01-01

    Hess is an international experiment on astrophysics settled in altitude in Namibia and whose aim is the study of cosmic radiation sources through the indirect detection of gamma rays whose energy ranges between 100 GeV and a few TeV. Hess is composed of 4 big telescopes located at the 4 summits of a square whose sides are 120 m long. This pattern of telescopes allows the stereoscopic reconstruction of the particles showers issued from the interaction of a cosmic particle with the atmosphere and enables scientists to tell electromagnetic showers from hadronic showers which are broader and more asymmetrical. These 4 telescopes detect the Cherenkov light. Hess has been operating since december 2003. Hess has detected for the first time a binary system in our galaxy. The center of our galaxy has been examined by Hess. The spectrum measured fits a power law well and the contribution of possible neutralinos cannot be prevailing in the very low-sloped spectrum unless neutralinos have a mass greater than 7.5 TeV which is very unlikely. Hess has enabled us to show the shell pattern in the gamma mapping of the remnants of the super-nova RXJ-1713-3946. (A.C.)

  18. Origins Space Telescope: 3D infrared surveys of star formation and black hole growth in galaxies over cosmic time

    Science.gov (United States)

    Pope, Alexandra; Armus, Lee; bradford, charles; Origins Space Telescope STDT

    2018-01-01

    In the coming decade, new telescope facilities and surveys aim to provide a 3D map of the unobscured Universe over cosmic time. However, much of galaxy formation and evolution occurs behind dust, and is only observable through infrared observations. Previous extragalactic infrared surveys were fundamentally limited to a 2D mapping of the most extreme populations of galaxies due to spatial resolution and sensitivity. The Origins Space Telescope (OST) is the mission concept for the Far-Infrared Surveyor, one of the four science and technology definition studies sponsored by NASA to provide input to the 2020 Astronomy and Astrophysics Decadal survey. OST is planned to be a large aperture, actively-cooled telescope covering a wide span of the mid- to far-infrared spectrum, which will achieve spectral line sensitivities up to 1000 times deeper than previous infrared facilities. With powerful instruments such as the Medium Resolution Survey Spectrometer (MRSS), capable of simultaneous imaging and spectroscopy, the extragalactic infrared sky can finally be surveyed in 3D. In addition to spectroscopic redshifts, the rich suite of lines in the infrared provides unique diagnostics of the ongoing star formation (both obscured and unobscured) and the central supermassive black hole growth. In this poster, we present a simulated extragalactic survey with OST/MRSS which will detect millions of galaxies down to well below the knee of the infrared luminosity function. We demonstrate how this survey can map the coeval star formation and black hole growth in galaxies over cosmic time.

  19. Non-primordial origin of the cosmic background radiation and pregalactic density fluctuations

    International Nuclear Information System (INIS)

    Froehlich, H.E.; Mueller, V.; Oleak, H.

    1984-01-01

    Assumptions of a tepid Universe and a smaller primordial contribution to the 3 K background are made to show that Pop III stars may be responsible for the 3 K background and cosmic ray entropy. The 3 K background would be caused by thermalized stellar radiation produced by metallized intergalactic dust formed in first generation stars. A range of mass scales and amplification factors of density perturbations in the early Universe is examined below the Jeans mass for gravitational instabilities. The density perturbations that could have been present at small enough mass scales could have survived and generated sonic modes that propagated through the plasma era and, when combined with additional gravitationally unstable entropy disturbances after recombination, triggered the formation of Pop III stars. 13 references

  20. The cosmic large-scale structure, dark matter and the origin of galaxies

    CERN Document Server

    Frenk, Carlos S

    1998-01-01

    In this series of lectures, I will review the main events and processes which are thought to have led to the build of structure in the Universe. First, I will provide an overview of some basic ideas such as inflation, Big Bang nucleosynthesis, the microwave background radiation and gravitanional instability. I will then dicuss the evidence for dark matter in the universe and current ideas on the nature and amount of this dark matter, including their consequences for the values of the fundamental cosmological parameters. Next, I will review the processes that give rise to the cosmic large-scale structure, starting with a discussion of the main fluctuation damping mechanisms at early times and finishing with a description of the non-linear phases of evolution. I will discuss how these calculations compare with observations and present the current status of competing cosmological models. Finally I will summarize the most recent and very exciting developments in observational and theoretical studies of gala...

  1. The JEM-EUSO mission: a space observatory to study the origin of Ultra-High Energy Cosmic Rays

    Energy Technology Data Exchange (ETDEWEB)

    Bertaina, M. [Department of Physics, University of Torino and INFN, Torino (Italy); Parizot, E. [APC, Univ Paris Diderot, CNRS/IN2P3, CEA/Irfu, Obs de Paris, Sorbonne Paris Cité (France)

    2014-11-15

    The Extreme Universe Space Observatory (EUSO) onboard the Japanese Experiment Module (JEM-EUSO) of the International Space Station (ISS) is an innovative space-based mission with the aim of detecting Ultra-High Energy Cosmic Rays (UHECRs) from the ISS, by using the Earth's atmosphere as a calorimeter viewed by a fluorescence telescope. An observatory able to produce an arrival direction map with more than several hundreds events above 5 × 10{sup 19} eV would give important information on the origin of the UHECRs and identify structures in the sky map that contain information about the source density and/or distribution. This is likely to lead to an understanding of the acceleration mechanisms with a high potential for producing discoveries in astrophysics and/or fundamental physics. The scientific motivations of the mission as well as the current development status of the instrument and its performance are reviewed.

  2. The JEM-EUSO mission: a space observatory to study the origin of Ultra-High Energy Cosmic Rays

    International Nuclear Information System (INIS)

    Bertaina, M.; Parizot, E.

    2014-01-01

    The Extreme Universe Space Observatory (EUSO) onboard the Japanese Experiment Module (JEM-EUSO) of the International Space Station (ISS) is an innovative space-based mission with the aim of detecting Ultra-High Energy Cosmic Rays (UHECRs) from the ISS, by using the Earth's atmosphere as a calorimeter viewed by a fluorescence telescope. An observatory able to produce an arrival direction map with more than several hundreds events above 5 × 10 19 eV would give important information on the origin of the UHECRs and identify structures in the sky map that contain information about the source density and/or distribution. This is likely to lead to an understanding of the acceleration mechanisms with a high potential for producing discoveries in astrophysics and/or fundamental physics. The scientific motivations of the mission as well as the current development status of the instrument and its performance are reviewed

  3. Divine Emanation As Cosmic Origin: Ibn Sînâ and His Critics

    Directory of Open Access Journals (Sweden)

    Syamsuddin Arif

    2012-11-01

    Full Text Available The question of cosmic beginning has always attracted considerable attention from serious thinkers past and present. Among many contesting theories that have emerged, that of emanation was appropriated by Muslim philosophers like Ibn Sînâ in order to reconcile the Aristotelian doctrine of the eternity of matter with the teaching of al-Qur’ân on the One Creator-God. According to this theory, the universe, which comprises a multitude of  entities, is generated from a transcendent Being, the One, that is unitary, through the medium of  a hierarchy of  immaterial substances. While the ultimate source is undiminished, the beings which are emanated are progressively less perfect as they are further removed from the first principle. The process is conceived as being atemporal and often compared to the efflux of light from a luminous body, or to water flowing from a spring. This metaphysical theory has enabled Ibn Sînâ to solve the vexed problem: given an eternally existing world and one eternally existing God, how can the two necessarily co-exist without having the perfect, simple unity of God destroyed by contact with the multiplicity of material things? The following essay delineates and evaluates both Ibn Sînâ’s arguments as well as the counter-arguments of  his critics.

  4. Origins and early days of the Bristol school of cosmic-ray physics

    International Nuclear Information System (INIS)

    Lock, W.O.

    1990-01-01

    The founder of the Bristol School was Cecil Frank Powell, Nobel Laureate for Physics in 1950 for his discovery of the pi-meson and sometimes called the father of meson physics. The article describes first his early life and his many years of systematic work to perfect the nuclear emulsion technique. This is followed by a brief description of the circumstances of the discovery of the pi-meson and of the so-called 'strange particles'. An attempt is made to give a portrait of Powell and to explain his success in building up one of the first post-war international research teams, which paved the way for large international laboratories such as CERN. The account concludes with some personal memories of the award of the Nobel Prize and of the happy and creative atmosphere which Powell created around him at one of the most exciting times in the physics of cosmic rays since their discovery just after the beginning of the century. (author)

  5. Sagittarius A* as an origin of the Galactic PeV cosmic rays?

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Yutaka [Department of Earth and Space Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043 (Japan); Murase, Kohta; Kimura, Shigeo S., E-mail: fujita@vega.ess.sci.osaka-u.ac.jp, E-mail: murase@psu.edu, E-mail: szk323@psu.edu [Center for Particle and Gravitational Astrophysics, Department of Physics, Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States)

    2017-04-01

    Supernova remnants (SNRs) have commonly been considered as a source of the observed PeV cosmic rays (CRs) or a Galactic PeV particle accelerator ('Pevatron'). In this work, we study Sagittarius A* (Sgr A*), which is the low-luminosity active galactic nucleus of the Milky Way Galaxy, as another possible canditate of the Pevatron, because it sometimes became very active in the past. We assume that a large number of PeV CRs were injected by Sgr A* at the outburst about 10{sup 7} yr ago when the Fermi bubbles were created. We constrain the diffusion coefficient for the CRs in the Galactic halo on the condition that the CRs have arrived on the Earth by now, while a fairly large fraction of them have escaped from the halo. Based on a diffusion-halo model, we solve a diffusion equation for the CRs and compare the results with the CR spectrum on the Earth. The observed small anisotropy of the arrival directions of CRs may be explained if the diffusion coefficient in the Galactic disk is smaller than that in the halo. Our model predicts that a boron-to-carbon ratio should be energy-independent around the knee, where the CRs from Sgr A* become dominant. It is unlikely that the spectrum of the CRs accelerated at the outburst is represented by a power-law similar to the one for those responsible for the gamma-ray emission from the central molecular zone (CMZ) around the Galactic center.

  6. Selected Theoretical Studies Group contributions to the 14th International Cosmic Ray conference. [including studies on galactic molecular hydrogen, interstellar reddening, and on the origin of cosmic rays

    Science.gov (United States)

    1975-01-01

    The galactic distribution of H2 was studied through gamma radiation and through X-ray, optical, and infrared absorption measurements from SAS-2 and other sources. A comparison of the latitude distribution of gamma-ray intensity with reddening data shows reddening data to give the best estimate of interstellar gas in the solar vicinity. The distribution of galactic cosmic ray nucleons was determined and appears to be identical to the supernova remnant distribution. Interactions between ultrahigh energy cosmic-ray nuclei and intergalactic photon radiation fields were calculated, using the Monte Carlo method.

  7. Origins of sharp cosmic-ray electron structures and the DAMPE excess

    Science.gov (United States)

    Huang, Xian-Jun; Wu, Yue-Liang; Zhang, Wei-Hong; Zhou, Yu-Feng

    2018-05-01

    Nearby sources may contribute to cosmic-ray electron (CRE) structures at high energies. Recently, the first DAMPE results on the CRE flux hinted at a narrow excess at energy ˜1.4 TeV . We show that in general a spectral structure with a narrow width appears in two scenarios. The first is spectrum broadening for the continuous sources with a δ -function-like injection spectrum. In this scenario, a finite width can develop after propagation through the Galaxy, which can reveal the distance of the source. Well-motivated sources include minispikes and subhalos formed by dark matter (DM) particles χs which annihilate directly into e+e- pairs. The second is phase-space shrinking for burstlike sources with a power-law-like injection spectrum. The spectrum after propagation can shrink at a cooling-related cutoff energy and form a sharp spectral peak. The peak can be more prominent due to the energy-dependent diffusion. In this scenario, the width of the excess constrains both the power index and the distance of the source. Possible such sources are pulsar wind nebulae (PWNe) and supernova remnants (SNRs). We analysis the DAMPE excess and find that the continuous DM sources should be fairly close within ˜0.3 kpc , and the annihilation cross sections are close to the thermal value. For the burstlike source, the narrow width of the excess suggests that the injection spectrum must be hard with power index significantly less than two, the distance is within ˜(3 - 4 ) kpc , and the age of the source is ˜0.16 Myr . In both scenarios, large anisotropies in the CRE flux are predicted. We identify possible candidates of minispike and PWN sources in the current Fermi-LAT 3FGL and ATNF catalog, respectively. The diffuse γ -rays from these sources can be well below the Galactic diffuse γ -ray backgrounds and less constrained by the Fermi-LAT data, if they are located at the low Galactic latitude regions.

  8. The evolving universe and the origin of life the search for our cosmic roots

    CERN Document Server

    Teerikorpi, Pekka; Lehto, Harry; Chernin, Arthur; Byrd, Gene; Lehto, K

    2008-01-01

    Sir Isaac Newton famously said, regarding his discoveries, "If I have seen further it is by standing upon the shoulders of giants." The Evolving Universe and the Origin of Life describes, complete with fascinating biographical details of the thinkers involved, the ascent to the metaphorical shoulders accomplished by the greatest minds in history. For the first time, a single book can take the reader on a journey through the history of the universe as interpreted by the expanding body of knowledge of humankind. From subatomic particles to the protein chains that form life, and expanding in scale to the entire universe, this book covers the science that explains how we came to be. The Evolving Universe and the Origin of Life contains a great breadth of knowledge, from astronomy to physics, from chemistry to biology. It includes over 350 figures that enhance the comprehension of concepts both basic and advanced, and is a non-technical, easy-to-read text at an introductory college level that is ideal for anyone i...

  9. Using commercial amateur astronomical spectrographs

    CERN Document Server

    Hopkins, Jeffrey L

    2014-01-01

    Amateur astronomers interested in learning more about astronomical spectroscopy now have the guide they need. It provides detailed information about how to get started inexpensively with low-resolution spectroscopy, and then how to move on to more advanced  high-resolution spectroscopy. Uniquely, the instructions concentrate very much on the practical aspects of using commercially-available spectroscopes, rather than simply explaining how spectroscopes work. The book includes a clear explanation of the laboratory theory behind astronomical spectrographs, and goes on to extensively cover the practical application of astronomical spectroscopy in detail. Four popular and reasonably-priced commercially available diffraction grating spectrographs are used as examples. The first is a low-resolution transmission diffraction grating, the Star Analyser spectrograph. The second is an inexpensive fiber optic coupled bench spectrograph that can be used to learn more about spectroscopy. The third is a newcomer, the ALPY ...

  10. Second generation spectrograph for the Hubble Space Telescope

    Science.gov (United States)

    Woodgate, B. E.; Boggess, A.; Gull, T. R.; Heap, S. R.; Krueger, V. L.; Maran, S. P.; Melcher, R. W.; Rebar, F. J.; Vitagliano, H. D.; Green, R. F.; Wolff, S. C.; Hutchings, J. B.; Jenkins, E. B.; Linsky, J. L.; Moos, H. W.; Roesler, F.; Shine, R. A.; Timothy, J. G.; Weistrop, D. E.; Bottema, M.; Meyer, W.

    1986-01-01

    The preliminary design for the Space Telescope Imaging Spectrograph (STIS), which has been selected by NASA for definition study for future flight as a second-generation instrument on the Hubble Space Telescope (HST), is presented. STIS is a two-dimensional spectrograph that will operate from 1050 A to 11,000 A at the limiting HST resolution of 0.05 arcsec FWHM, with spectral resolutions of 100, 1200, 20,000, and 100,000 and a maximum field-of-view of 50 x 50 arcsec. Its basic operating modes include echelle model, long slit mode, slitless spectrograph mode, coronographic spectroscopy, photon time-tagging, and direct imaging. Research objectives are active galactic nuclei, the intergalactic medium, global properties of galaxies, the origin of stellar systems, stelalr spectral variability, and spectrographic mapping of solar system processes.

  11. THE ORIGIN OF THE COSMIC GAMMA-RAY BACKGROUND IN THE MeV RANGE

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz-Lapuente, Pilar [Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, c/. Serrano 121, E-28006, Madrid (Spain); The, Lih-Sin; Hartmann, Dieter H.; Ajello, Marco [Department of Physics and Astronomy, Clemson University, Clemson, SC 29634 (United States); Canal, Ramon [Institut de Ciències del Cosmos (UB-IEEC), c/. Martí i Franqués 1, E-08028, Barcelona (Spain); Röpke, Friedrich K.; Ohlmann, Sebastian T. [Institute of Theoretical Physics and Astrophysics, University of Würzburg, D-97074, Würzburg (Germany); Hillebrandt, Wolfgang [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching bei München (Germany)

    2016-04-01

    There has been much debate about the origin of the diffuse γ-ray background in the MeV range. At lower energies, AGNs and Seyfert galaxies can explain the background, but not above ≃0.3 MeV. Beyond ∼10 MeV blazars appear to account for the flux observed. That leaves an unexplained gap for which different candidates have been proposed, including annihilations of WIMPS. One candidate is Type Ia supernovae (SNe Ia). Early studies concluded that they were able to account for the γ-ray background in the gap, while later work attributed a significantly lower contribution to them. All those estimates were based on SN Ia explosion models that did not reflect the full 3D hydrodynamics of SN Ia explosions. In addition, new measurements obtained since 2010 have provided new, direct estimates of high-z SN Ia rates beyond z ∼ 2. We take into account these new advances to see the predicted contribution to the gamma-ray background. We use here a wide variety of explosion models and a plethora of new measurements of SN Ia rates. SNe Ia still fall short of the observed background. Only for a fit, which would imply ∼150% systematic error in detecting SN Ia events, do the theoretical predictions approach the observed fluxes. This fit is, however, at odds at the highest redshifts with recent SN Ia rate estimates. Other astrophysical sources such as flat-spectrum radio quasars do match the observed flux levels in the MeV regime, while SNe Ia make up to 30%–50% of the observed flux.

  12. THE ORIGIN OF THE COSMIC GAMMA-RAY BACKGROUND IN THE MeV RANGE

    International Nuclear Information System (INIS)

    Ruiz-Lapuente, Pilar; The, Lih-Sin; Hartmann, Dieter H.; Ajello, Marco; Canal, Ramon; Röpke, Friedrich K.; Ohlmann, Sebastian T.; Hillebrandt, Wolfgang

    2016-01-01

    There has been much debate about the origin of the diffuse γ-ray background in the MeV range. At lower energies, AGNs and Seyfert galaxies can explain the background, but not above ≃0.3 MeV. Beyond ∼10 MeV blazars appear to account for the flux observed. That leaves an unexplained gap for which different candidates have been proposed, including annihilations of WIMPS. One candidate is Type Ia supernovae (SNe Ia). Early studies concluded that they were able to account for the γ-ray background in the gap, while later work attributed a significantly lower contribution to them. All those estimates were based on SN Ia explosion models that did not reflect the full 3D hydrodynamics of SN Ia explosions. In addition, new measurements obtained since 2010 have provided new, direct estimates of high-z SN Ia rates beyond z ∼ 2. We take into account these new advances to see the predicted contribution to the gamma-ray background. We use here a wide variety of explosion models and a plethora of new measurements of SN Ia rates. SNe Ia still fall short of the observed background. Only for a fit, which would imply ∼150% systematic error in detecting SN Ia events, do the theoretical predictions approach the observed fluxes. This fit is, however, at odds at the highest redshifts with recent SN Ia rate estimates. Other astrophysical sources such as flat-spectrum radio quasars do match the observed flux levels in the MeV regime, while SNe Ia make up to 30%–50% of the observed flux

  13. Synthetic nebular emission from massive galaxies - I: origin of the cosmic evolution of optical emission-line ratios

    Science.gov (United States)

    Hirschmann, Michaela; Charlot, Stephane; Feltre, Anna; Naab, Thorsten; Choi, Ena; Ostriker, Jeremiah P.; Somerville, Rachel S.

    2017-12-01

    Galaxies occupy different regions of the [O III]λ5007/H β-versus-[N II]λ6584/H α emission-line ratio diagram in the distant and local Universe. We investigate the origin of this intriguing result by modelling self-consistently, for the first time, nebular emission from young stars, accreting black holes (BHs) and older, post-asymptotic giant branch (post-AGB) stellar populations in galaxy formation simulations in a full cosmological context. In post-processing, we couple new-generation nebular-emission models with high-resolution, cosmological zoom-in simulations of massive galaxies to explore which galaxy physical properties drive the redshift evolution of the optical-line ratios [O III]λ5007/H β, [N II]λ6584/H α, [S II]λλ6717, 6731/H α and [O I]λ6300/H α. The line ratios of simulated galaxies agree well with observations of both star-forming and active local Sloan Digital Sky Survey galaxies. Towards higher redshifts, at fixed galaxy stellar mass, the average [O III]/H β is predicted to increase and [N II]/H α, [S II]/H α and [O I]/H α to decrease - widely consistent with observations. At fixed stellar mass, we identify star formation history, which controls nebular emission from young stars via the ionization parameter, as the primary driver of the cosmic evolution of [O III]/H β and [N II]/H α. For [S II]/H α and [O I]/H α, this applies only to redshifts greater than z = 1.5, the evolution at lower redshift being driven in roughly equal parts by nebular emission from active galactic nuclei and post-AGB stellar populations. Instead, changes in the hardness of ionizing radiation, ionized-gas density, the prevalence of BH accretion relative to star formation and the dust-to-metal mass ratio (whose impact on the gas-phase N/O ratio we model at fixed O/H) play at most a minor role in the cosmic evolution of simulated galaxy line ratios.

  14. Cosmic vacuum

    International Nuclear Information System (INIS)

    Chernin, Artur D

    2001-01-01

    Recent observational studies of distant supernovae have suggested the existence of cosmic vacuum whose energy density exceeds the total density of all the other energy components in the Universe. The vacuum produces the field of antigravity that causes the cosmological expansion to accelerate. It is this accelerated expansion that has been discovered in the observations. The discovery of cosmic vacuum radically changes our current understanding of the present state of the Universe. It also poses new challenges to both cosmology and fundamental physics. Why is the density of vacuum what it is? Why do the densities of the cosmic energy components differ in exact value but agree in order of magnitude? On the other hand, the discovery made at large cosmological distances of hundreds and thousands Mpc provides new insights into the dynamics of the nearby Universe, the motions of galaxies in the local volume of 10 - 20 Mpc where the cosmological expansion was originally discovered. (reviews of topical problems)

  15. Cosmic vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Chernin, Artur D [P.K. Shternberg State Astronomical Institute at the M.V. Lomonosov Moscow State University, Moscow (Russian Federation)

    2001-11-30

    Recent observational studies of distant supernovae have suggested the existence of cosmic vacuum whose energy density exceeds the total density of all the other energy components in the Universe. The vacuum produces the field of antigravity that causes the cosmological expansion to accelerate. It is this accelerated expansion that has been discovered in the observations. The discovery of cosmic vacuum radically changes our current understanding of the present state of the Universe. It also poses new challenges to both cosmology and fundamental physics. Why is the density of vacuum what it is? Why do the densities of the cosmic energy components differ in exact value but agree in order of magnitude? On the other hand, the discovery made at large cosmological distances of hundreds and thousands Mpc provides new insights into the dynamics of the nearby Universe, the motions of galaxies in the local volume of 10 - 20 Mpc where the cosmological expansion was originally discovered. (reviews of topical problems)

  16. Cosmic ray variations of solar origin in relation to human physiological state during the December 2006 solar extreme events

    Science.gov (United States)

    Papailiou, M.; Mavromichalaki, H.; Vassilaki, A.; Kelesidis, K. M.; Mertzanos, G. A.; Petropoulos, B.

    2009-02-01

    There is an increasing amount of evidence linking biological effects to solar and geomagnetic disturbances. A series of studies is published referring to the changes in human physiological responses at different levels of geomagnetic activity. In this study, the possible relation between the daily variations of cosmic ray intensity, measured by the Neutron Monitor at the Cosmic Ray Station of the University of Athens (http://cosray.phys.uoa.gr) and the average daily and hourly heart rate variations of persons, with no symptoms or hospital admission, monitored by Holter electrocardiogram, is considered. This work refers to a group of persons admitted to the cardiological clinic of the KAT Hospital in Athens during the time period from 4th to 24th December 2006 that is characterized by extreme solar and geomagnetic activity. A series of Forbush decreases started on 6th December and lasted until the end of the month and a great solar proton event causing a Ground Level Enhancement (GLE) of the cosmic ray intensity on 13th December occurred. A sudden decrease of the cosmic ray intensity on 15th December, when a geomagnetic storm was registered, was also recorded in Athens Neutron Monitor station (cut-off rigidity 8.53 GV) with amplitude of 4%. It is noticed that during geomagnetically quiet days the heart rate and the cosmic ray intensity variations are positively correlated. When intense cosmic ray variations, like Forbush decreases and relativistic proton events produced by strong solar phenomena occur, cosmic ray intensity and heart rate get minimum values and their variations, also, coincide. During these events the correlation coefficient of these two parameters changes and follows the behavior of the cosmic ray intensity variations. This is only a small part of an extended investigation, which has begun using data from the year 2002 and is still in progress.

  17. Particle spectra and mass composition in the ultra-high energy region in the framework of the Galactic origin of cosmic rays

    Directory of Open Access Journals (Sweden)

    Lagutin A.A.

    2017-01-01

    Full Text Available The possibility for a self-consistent description of all the basic features of the observed cosmic ray spectra and primary composition variations in the energy range of 1015 ÷ 1020 eV within the Galactic origin scenario is examined. We assume the existence of Galactic sources that accelerate particles up to ∼ 3 · 1018Z eV and take into account a highly inhomogeneous (fractal-like distribution of matter and magnetic fields in the Galaxy that leads to extremely large free paths of particles (“Lévy flights”, along with an overwhelming contribution to the cosmic ray fluxes observed above ∼1018 eV from particles reaching the Solar System without scattering. Our scenario was refined on the basis of recent experimental results on primary mass composition. Model predictions, which could be verified with the improved high-precision measurements in the nearest future are discussed.

  18. Princeton Cyclotron QDDD spectrograph system

    International Nuclear Information System (INIS)

    Kouzes, R.T.

    1985-01-01

    A review of experiments involving the Princeton Quadrupole-Dipole-Dipole- Dipole (QDDD) spectrograph is given. The QDDD is a high resolution, large solid angle device which is combined with the azymuthally varying field (AVF) cyclotron. Some reactions involving 3 He beams are discussed

  19. Spectrographic analysis of plutonium (1960)

    International Nuclear Information System (INIS)

    Artaud, J.; Chaput, M.; Robichet, J.

    1960-01-01

    Various possibilities for the spectrographic determination of impurities in plutonium are considered. The application of the 'copper spark' method, of sparking on graphite and of fractional distillation in the arc are described and discussed in some detail (apparatus, accessories, results obtained). (author) [fr

  20. Detection Of Alterations In Audio Files Using Spectrograph Analysis

    Directory of Open Access Journals (Sweden)

    Anandha Krishnan G

    2015-08-01

    Full Text Available The corresponding study was carried out to detect changes in audio file using spectrograph. An audio file format is a file format for storing digital audio data on a computer system. A sound spectrograph is a laboratory instrument that displays a graphical representation of the strengths of the various component frequencies of a sound as time passes. The objectives of the study were to find the changes in spectrograph of audio after altering them to compare altering changes with spectrograph of original files and to check for similarity and difference in mp3 and wav. Five different alterations were carried out on each audio file to analyze the differences between the original and the altered file. For altering the audio file MP3 or WAV by cutcopy the file was opened in Audacity. A different audio was then pasted to the audio file. This new file was analyzed to view the differences. By adjusting the necessary parameters the noise was reduced. The differences between the new file and the original file were analyzed. By adjusting the parameters from the dialog box the necessary changes were made. The edited audio file was opened in the software named spek where after analyzing a graph is obtained of that particular file which is saved for further analysis. The original audio graph received was combined with the edited audio file graph to see the alterations.

  1. Cosmic rays around 1018 eV: Implications of contemporary measurements on the origin of the ankle feature

    International Nuclear Information System (INIS)

    Deligny, O.

    2014-01-01

    The impressive power-law decay of the energy spectrum of cosmic rays over more than thirty orders of magnitude in intensity and for energies ranging over eleven decades between 10 9 eV and 10 20 eV is actually dotted with small irregularities. These irregularities are highly valuable for uncovering and understanding the modes of production and propagation of cosmic rays. They manifest themselves through changes in the spectral index characterising the observed power laws. One of these irregularities, known as the ankle, is a hardening of the energy spectrum of cosmic rays in the 10 18 eV energy range. There are many possible interpretations for explaining it. One is to say that the ankle may be the spectral feature marking the transition between Galactic and extragalactic cosmic rays. Another one is to understand the ankle as the natural distortion of a proton-dominated extragalactic spectrum due to e ± pair production in the collisions with the photons of the cosmic microwave background. While the data collected at the Telescope Array supports the second explanation, the data collected at the Pierre Auger Observatory requires a totally different picture in terms of introducing a new component mainly composed of light elements in order to fill the gap of the all-particle energy spectrum between 10 17 eV and 4*10 18 eV, and to reproduce the measurements related to mass composition. If contemporary observations characterising the ankle have shed new lights, they are still far from being able to deliver all the story

  2. Origin of the ankle in the ultrahigh energy cosmic ray spectrum, and of the extragalactic protons below it

    Science.gov (United States)

    Unger, Michael; Farrar, Glennys R.; Anchordoqui, Luis A.

    2015-12-01

    The sharp change in slope of the ultrahigh energy cosmic ray (UHECR) spectrum around 1 018.6 eV (the ankle), combined with evidence of a light but extragalactic component near and below the ankle and intermediate composition above, has proved exceedingly challenging to understand theoretically, without fine-tuning. We propose a mechanism whereby photo-disintegration of ultrahigh energy nuclei in the region surrounding a UHECR accelerator accounts for the observed spectrum and inferred composition at Earth. For suitable source conditions, the model reproduces the spectrum and the composition over the entire extragalactic cosmic ray energy range, i.e. above 1 017.5 eV . Predictions for the spectrum and flavors of neutrinos resulting from this process are also presented.

  3. Deepening Cosmic Education

    Science.gov (United States)

    Leonard, Gerard

    2013-01-01

    This article is a special blend of research, theory, and practice, with clear insight into the origins of Cosmic Education and cosmic task, while recalling memories of student explorations in botany, in particular, episodes from Mr. Leonard's teaching. Mr. Leonard speaks of a storytelling curriculum that eloquently puts perspective into dimensions…

  4. Cosmic Accelerators: An Introduction

    International Nuclear Information System (INIS)

    Kanbach, Gottfried

    2005-01-01

    High energy, relativistic, particles are an essential component of the Universe and play a major role in astrophysics. In a few years we will reach the centennial of the discovery of cosmic rays; all through this century the properties, origin, and effects of this radiation have intrigued researchers in astrophysics and elementary particles alike. We briefly review the history, current status, and future perspectives of cosmic ray research. Emphasis will be placed on the multitude of cosmic accelerators, direct observations of these objects, and the effects of cosmic rays in the Galaxy and beyond

  5. The Behavior of Warm Molecules in Planet-forming Disks and CHESS: a Pathfinder UV Spectrograph for the LUVOIR Surveyor

    Science.gov (United States)

    Hoadley, Keri; France, Kevin

    2017-01-01

    Understanding the evolution of gas over the lifetime of protoplanetary disks provides us with important clues about how planet formation mechanisms drive the diversity of exoplanetary systems observed to date. In the first part of my talk, I will discuss how we use emission line observations of molecular hydrogen (H2) in the far-ultraviolet (far-UV) with the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope to study the warm molecular regions (a CHESS), built as a demonstration of one component of the LUVOIR spectrograph and new technological improvements to UV optical components for the next generation of near- to far-UV astrophysical observatories. CHESS is a far-UV sounding rocket experiment designed to probe the warm and cool atoms and molecules near sites of recent star formation in the local interstellar medium. I will talk about the science goals, design, research and development (R&D) components, and calibration of the CHESS instrument. I will end by presenting the initial data reduction and results of the flight observations taken during the second launch of CHESS.

  6. The LUVOIR Ultraviolet Multi-Object Spectrograph (LUMOS): instrument definition and design

    Science.gov (United States)

    France, Kevin; Fleming, Brian; West, Garrett; McCandliss, Stephan R.; Bolcar, Matthew R.; Harris, Walter; Moustakas, Leonidas; O'Meara, John M.; Pascucci, Ilaria; Rigby, Jane; Schiminovich, David; Tumlinson, Jason

    2017-08-01

    The Large Ultraviolet/Optical/Infrared Surveyor (LUVOIR) is one of four large mission concepts currently undergoing community study for consideration by the 2020 Astronomy and Astrophysics Decadal Survey. LUVOIR is being designed to pursue an ambitious program of exoplanetary discovery and characterization, cosmic origins astrophysics, and planetary science. The LUVOIR study team is investigating two large telescope apertures (9- and 15-meter primary mirror diameters) and a host of science instruments to carry out the primary mission goals. Many of the exoplanet, cosmic origins, and planetary science goals of LUVOIR require high-throughput, imaging spectroscopy at ultraviolet (100 - 400 nm) wavelengths. The LUVOIR Ultraviolet Multi-Object Spectrograph, LUMOS, is being designed to support all of the UV science requirements of LUVOIR, from exoplanet host star characterization to tomography of circumgalactic halos to water plumes on outer solar system satellites. LUMOS offers point source and multi-object spectroscopy across the UV bandpass, with multiple resolution modes to support different science goals. The instrument will provide low (R = 8,000 - 18,000) and medium (R = 30,000 - 65,000) resolution modes across the far-ultraviolet (FUV: 100 - 200 nm) and nearultraviolet (NUV: 200 - 400 nm) windows, and a very low resolution mode (R = 500) for spectroscopic investigations of extremely faint objects in the FUV. Imaging spectroscopy will be accomplished over a 3 × 1.6 arcminute field-of-view by employing holographically-ruled diffraction gratings to control optical aberrations, microshutter arrays (MSA) built on the heritage of the Near Infrared Spectrograph (NIRSpec) on the James Webb Space Telescope (JWST), advanced optical coatings for high-throughput in the FUV, and next generation large-format photon-counting detectors. The spectroscopic capabilities of LUMOS are augmented by an FUV imaging channel (100 - 200nm, 13 milliarcsecond angular resolution, 2 × 2

  7. On the problem of the flux value of cosmic origin radioisotopes on the Earth and their time variations

    International Nuclear Information System (INIS)

    Styro, B.I.; Luyanas, V.Yu.; Zinkyavichyus, P.K.

    1977-01-01

    Cosmogenic radioisotopes flows on the Earth's surface are investigated. Nuclear reactions by the action of slow neutrons (cosmic rays) are analysed. It has been testified that the role of Ne, Kr, Ze and nuclei of the volcanic substance in production of cosmogenic nuclids is insignificant. Radioisotopes can provide by meteorites while passing through the atmosphere as a result of ablation. The evaluations of the meteoritic sustance falling out to the Earth can be used as a base to calculate flows of a number of radioactive isotopes. The flow density of most isotopes which come with the meteoric substance are quite insignificant. However the 26 Al flows can be of the same value as that of the rate of their production in the atmosphere. Changes of the rate of the production of cosmogenic isotopes both due to the flow variations meteoric and as a result of the cosmic ray intensity oscillations first of all effect the stratospheral reservoir. Time oscillations of cosmogenic radioisotope flows to the Earth's surface will occur with some delay because the life time of isotopes in the stratosphere lasts several years. The evaluation is given of the difference of phases between oscillations of the stratospheral rate of the formation of long-living isotopes and the flow density to the Earth's surface. It can approximate to 1-2 years

  8. Spectrographic analysis of stainless steels

    International Nuclear Information System (INIS)

    Sabato, S.F.; Lordello, A.R.

    1984-01-01

    Two spectrogaphyic solution techniques, 'Porous Cup' and 'Vacuum Cup', were investigated in order to determine the minor constituents (Cr, Ni, Mo, Mn, Cu and V) of stainless steels. Iron and cobalt were experimented as internal standards. The precision varied from 4 to 11% for both spectrographic techniques, in which cobalt was used as international standard. Certified standards from National Bureau of Standards and Instituto de Pesquisas Tecnologicas were analysed to verify the accuracy of both techniques. The best accuracy was obtained with the Vacuum Cup techniques. (Author) [pt

  9. The mineralogy and petrology of I-type cosmic spherules: Implications for their sources, origins and identification in sedimentary rocks

    Science.gov (United States)

    Genge, Matthew J.; Davies, Bridie; Suttle, Martin D.; van Ginneken, Matthias; Tomkins, Andrew G.

    2017-12-01

    I-type cosmic spherules are micrometeorites that formed by melting during atmospheric entry and consist mainly of iron oxides and FeNi metal. I-types are important because they can readily be recovered from sedimentary rocks allowing study of solar system events over geological time. We report the results of a study of the mineralogy and petrology of 88 I-type cosmic spherules recovered from Antarctica in order to evaluate how they formed and evolved during atmospheric entry, to constrain the nature of their precursors and to establish rigorous criteria by which they may be conclusively identified within sediments and sedimentary rocks. Two textural types of I-type cosmic spherule are recognised: (1) metal bead-bearing (MET) spherules dominated by Ni-poor (100 and suggest that metal from H-group ordinary, CM, CR and iron meteorites may form the majority of particles. Oxidation during entry heating increases in the series MET 80 wt% Ni comprising a particle mass fraction of exchange of Ni between wüstite and metal, and magnetite and wüstite are suggested as proxies for the rate of oxidation and cooling rate respectively. Variations in magnetite and wüstite crystal sizes are also suggested to relate to cooling rate allowing relative entry angle of particles to be evaluated. The formation of secondary metal in the form of sub-micron Ni-rich or Pt-group nuggets and as symplectite with magnetite was also identified and suggested to occur largely due to the exsolution of metallic alloys during decomposition of non-stoichiometric wüstite. Weathering is restricted to replacement of metal by iron hydroxides. The following criteria are recommended for the conclusive identification of I-type spherules within sediments and sedimentary rocks: (i) spherical particle morphologies, (ii) dendritic crystal morphologies, (iii) the presence of wüstite and magnetite, (iv) Ni-bearing wüstite and magnetite, and (v) the presence of relict FeNi metal.

  10. Spectrographic analysis of waste waters

    International Nuclear Information System (INIS)

    Alvarez Alduan, F.; Capdevila, C.

    1979-01-01

    The Influence of sodium and calcium, up to a maximum concentration of 1000 mg/1 Na and 300 mg/1 Ca, in the spectrographic determination of Cr, Cu, Fe,Mn and Pb in waste waters using graphite spark excitation has been studied. In order to eliminate this influence, each of the elements Ba, Cs, In, La, Li, Sr and Ti, as well as a mixture containing 5% Li-50% Ti, have been tested as spectrochemical buffers. This mixture allows to obtain an accuracy better than 25%. Sodium and calcium enhance the line intensities of impurities, when using graphite or gold electrodes, but they produce an opposite effect if copper or silver electrodes are used. (Author) 1 refs

  11. Spectrographic determination of impurities in uranium tetrafluoride matrices

    International Nuclear Information System (INIS)

    Reino, Luiz Carlos de Paula

    1980-01-01

    A direct spectrographic method for the determination of UF 4 impurities was developed. Investigations using spectrochemical carriers were carried out so to avoid uranium distillation, which as fluoride is much more volatile than the U 3 O 8 refractory matrix. The best results were obtained by using a mixture of MgO and NaCl carriers in the proportion of 20% and 10%, respectively, with respect to UF 4 matrix. An original spectrographic technique was introduced aiming to avoid the projection of sample particles outside the electrode during excitation. This new technique is based on the addition of a small quantity of a 0.5% gelatinous solution on the UF 4 tablet. The precision of the method was studied for each element analysed. The variation coefficients are within the range of 10 of 20%

  12. Spectrographic determination of impurities in uranium tetrafluoride matrices

    International Nuclear Information System (INIS)

    Reino, L.C.P.; Lordello, A.R.

    1980-01-01

    A direct spectrographic method for the determination of UF 4 impurities was developed. Investigations using spectrochemical carriers were carried out so to avoid uranium distillation, which as fluoride is much more volatile than the U 3 O 8 refractory matrix. The best results were obtained by using a mixture of MgO and NaCl carriers in the proportion of 20 and 10%, respectively, with respect to UF 4 matrix. An original spectrographic technique was introduced aiming to avoid the projection of sample particles outside the electrode during excitation. This new technique is based on the addition of a small quantity of a 0.5% gellatinous solution on the UF 4 tablet. The precision of the method was studied for each element analysed. The variation coefficients are within the range of 10 of 20%. (C.L.B.) [pt

  13. Cosmic strings and cosmic structure

    International Nuclear Information System (INIS)

    Albrecht, A.; Brandenberger, R.; Turok, N.

    1987-01-01

    The paper concerns the application of the theory of cosmic strings to explain the structure of the Universe. The formation of cosmic strings in the early Universe is outlined, along with the Big Bang theory, Grand Unified theories, and the first three minutes after the Big Bang. A description is given of the shaping of the Universe by cosmic strings, including the evolution of the string. The possibility for direct observation of cosmic strings is discussed. (U.K.)

  14. Multiradionuclide evidence for the solar origin of the cosmic-ray events of ?? 774/5 and 993/4

    OpenAIRE

    Mekhaldi, Florian; Muscheler, Raimund; Adolphi, Florian; Aldahan, Ala; Beer, J?rg; McConnell, Joseph R.; Possnert, G?ran; Sigl, Michael; Svensson, Anders; Synal, Hans-Arno; Welten, Kees C.; Woodruff, Thomas E.

    2015-01-01

    The origin of two large peaks in the atmospheric radiocarbon (C-14) concentration at AD 774/5 and 993/4 is still debated. There is consensus, however, that these features can only be explained by an increase in the atmospheric C-14 production rate due to an extraterrestrial event. Here we provide evidence that these peaks were most likely produced by extreme solar events, based on several new annually resolved Be-10 measurements from both Arctic and Antarctic ice cores. Using ice core Cl-36 d...

  15. Cosmic strings and galaxy formation

    Science.gov (United States)

    Bertschinger, Edmund

    1989-01-01

    The cosmogonical model proposed by Zel'dovich and Vilenkin (1981), in which superconducting cosmic strings act as seeds for the origin of structure in the universe, is discussed, summarizing the results of recent theoretical investigations. Consideration is given to the formation of cosmic strings, the microscopic structure of strings, gravitational effects, cosmic string evolution, and the formation of galaxies and large-scale structure. Simulation results are presented in graphs, and several outstanding issues are listed and briefly characterized.

  16. NRES: The Network of Robotic Echelle Spectrographs

    Science.gov (United States)

    Siverd, Robert; Brown, Tim; Henderson, Todd; Hygelund, John; Barnes, Stuart; de Vera, Jon; Eastman, Jason; Kirby, Annie; Smith, Cary; Taylor, Brook; Tufts, Joseph; van Eyken, Julian

    2018-01-01

    Las Cumbres Observatory (LCO) is building the Network of Robotic Echelle Spectrographs (NRES), which will consist of four (up to six in the future) identical, optical (390 - 860 nm) high-precision spectrographs, each fiber-fed simultaneously by up to two 1-meter telescopes and a Thorium-Argon calibration source. We plan to install one at up to 6 observatory sites in the Northern and Southern hemispheres, creating a single, globally-distributed, autonomous spectrograph facility using up to ten 1-m telescopes. Simulations suggest we will achieve long-term radial velocity precision of 3 m/s in less than an hour for stars brighter than V = 11 or 12 once the system reaches full capability. Acting in concert, these four spectrographs will provide a new, unique facility for stellar characterization and precise radial velocities.Following a few months of on-sky evaluation at our BPL test facility, the first spectrograph unit was shipped to CTIO in late 2016 and installed in March 2017. After several more months of additional testing and commissioning, regular science operations began with this node in September 2017. The second NRES spectrograph was installed at McDonald Observatory in September 2017 and released to the network after its own brief commissioning period, extending spectroscopic capability to the Northern hemisphere. The third NRES spectrograph was installed at SAAO in November 2017 and released to our science community just before year's end. The fourth NRES unit shipped in October and is currently en route to Wise Observatory in Israel with an expected release to the science community in early 2018.We will briefly overview the LCO telescope network, the NRES spectrograph design, the advantages it provides, and development challenges we encountered along the way. We will further discuss real-world performance from our first three units, initial science results, and the ongoing software development effort needed to automate such a facility for a wide array of

  17. Cosmic rays

    International Nuclear Information System (INIS)

    Tkachev, I.I.

    2014-01-01

    In this talk I will review results of cosmic ray observations at the highest energies. This year the new results on energy spectra, composition and the study of arrival directions of cosmic ray primaries came from the Telescope Array collaboration. I present these results in comparison with measurements done by other recent experiments and discuss their implications for the search of cosmic ray sources. Some related results in gamma-ray astronomy and selected recent advances in theory are also covered. (author)

  18. Curved VPH gratings for novel spectrographs

    Science.gov (United States)

    Clemens, J. Christopher; O'Donoghue, Darragh; Dunlap, Bart H.

    2014-07-01

    The introduction of volume phase holographic (VPH) gratings into astronomy over a decade ago opened new possibilities for instrument designers. In this paper we describe an extension of VPH grating technology that will have applications in astronomy and beyond: curved VPH gratings. These devices can disperse light while simultaneously correcting aberrations. We have designed and manufactured two different kinds of convex VPH grating prototypes for use in off-axis reflecting spectrographs. One type functions in transmission and the other in reflection, enabling Offnerstyle spectrographs with the high-efficiency and low-cost advantages of VPH gratings. We will discuss the design process and the tools required for modelling these gratings along with the recording layout and process steps required to fabricate them. We will present performance data for the first convex VPH grating produced for an astronomical spectrograph.

  19. Origin,

    Directory of Open Access Journals (Sweden)

    Artur de Vargas Giorgi

    2011-02-01

    Full Text Available This essay tightens the “origin” concept, its manifestation through puzzles and their relationship to techniques of reproduction. Contrary to the hegemonic critique of aesthetic and cultural objects – critique that, settled on the appearance and notions of identity, tradition, canon, etc., undervalues the reproductions of "originals" –, the aim is to deliver these objects from formal hierarchization dispositives, that is, release them of what is ideal and positively imposed, so that the reproducibility is potentiated as producer of singularities, of apparitions. The effort is to keep the undecided character of puzzles (bodies, texts, images in which the origin is manifest, so that the logic of the spectacle is reverted into sense opening, instance in which the aesthetic becomes a “performance” before contemporary complexity. With the reproducibility, an origin survives in passage: continually restored, but incomplete, present in trace, in absence.

  20. Cosmic ray investigations

    International Nuclear Information System (INIS)

    Zatsepin, Georgii T; Roganova, Tat'yana M

    2009-01-01

    The history of cosmic ray research at the Lebedev Institute beginning with the first work and continuing up to now is reviewed. The milestones and main avenues of research are outlined. Pioneering studies on the nuclear cascade process in extensive air showers, investigations of the Vavilov-Cherenkov radiation, and some work on the origin of cosmic rays are discussed. Recent data on ultrahigh-energy particle detection at the Pierre Auger Observatory and the High Resolution Fly's Eye (HiRes) experiments are presented. (conferences and symposia)

  1. Sky Subtraction with Fiber-Fed Spectrograph

    Science.gov (United States)

    Rodrigues, Myriam

    2017-09-01

    "Historically, fiber-fed spectrographs had been deemed inadequate for the observation of faint targets, mainly because of the difficulty to achieve high accuracy on the sky subtraction. The impossibility to sample the sky in the immediate vicinity of the target in fiber instruments has led to a commonly held view that a multi-object fibre spectrograph cannot achieve an accurate sky subtraction under 1% contrary to their slit counterpart. The next generation of multi-objects spectrograph at the VLT (MOONS) and the planed MOS for the E-ELT (MOSAIC) are fiber-fed instruments, and are aimed to observed targets fainter than the sky continuum level. In this talk, I will present the state-of-art on sky subtraction strategies and data reduction algorithm specifically developed for fiber-fed spectrographs. I will also present the main results of an observational campaign to better characterise the sky spatial and temporal variations ( in particular the continuum and faint sky lines)."

  2. Tomographic extreme-ultraviolet spectrographs: TESS.

    Science.gov (United States)

    Cotton, D M; Stephan, A; Cook, T; Vickers, J; Taylor, V; Chakrabarti, S

    2000-08-01

    We describe the system of Tomographic Extreme Ultraviolet (EUV) SpectrographS (TESS) that are the primary instruments for the Tomographic Experiment using Radiative Recombinative Ionospheric EUV and Radio Sources (TERRIERS) satellite. The spectrographs were designed to make high-sensitivity {80 counts/s)/Rayleigh [one Rayleigh is equivalent to 10(6) photons/(4pi str cm(2)s)}, line-of-sight measurements of the oi 135.6- and 91.1-nm emissions suitable for tomographic inversion. The system consists of five spectrographs, four identical nightglow instruments (for redundancy and added sensitivity), and one instrument with a smaller aperture to reduce sensitivity and increase spectral resolution for daytime operation. Each instrument has a bandpass of 80-140 nm with approximately 2- and 1-nm resolution for the night and day instruments, respectively. They utilize microchannel-plate-based two-dimensional imaging detectors with wedge-and-strip anode readouts. The instruments were designed, fabricated, and calibrated at Boston University, and the TERRIERS satellite was launched on 18 May 1999 from Vandenberg Air Force Base, California.

  3. Ultra high energy cosmic rays

    International Nuclear Information System (INIS)

    Watson, A.A.

    1986-01-01

    Cosmic radiation was discovered 70 years ago but its origin remains an open question. The background to this problem is outlined and attempts to discover the origin of the most energetic and rarest group above 10 15 eV are described. Measurements of the energy spectrum and arrival direction pattern of the very highest energy particles, mean energy about 6 x 10 19 eV, are used to argue that these particles originate outside our galaxy. Recent evidence from the new field of ultra high energy γ-ray astronomy are discussed in the context of a galactic origin hypothesis for lower energy cosmic rays. (author)

  4. General method of quantitative spectrographic analysis

    International Nuclear Information System (INIS)

    Capdevila, C.; Roca, M.

    1966-01-01

    A spectrographic method was developed to determine 23 elements in a wide range of concentrations; the method can be applied to metallic or refractory samples. Previous melting with lithium tetraborate and germanium oxide is done in order to avoid the influence of matrix composition and crystalline structure. Germanium oxide is also employed as internal standard. The resulting beads ar mixed with graphite powder (1:1) and excited in a 10 amperes direct current arc. (Author) 12 refs

  5. Cosmic microwave background, where next?

    CERN Multimedia

    CERN. Geneva

    2009-01-01

    Ground-based, balloon-borne and space-based experiments will observe the Cosmic Microwave Background in greater details to address open questions about the origin and the evolution of the Universe. In particular, detailed observations the polarization pattern of the Cosmic Microwave Background radiation have the potential to directly probe physics at the GUT scale and illuminate aspects of the physics of the very early Universe.

  6. Cosmic strings

    International Nuclear Information System (INIS)

    Bennett, D.P.

    1988-07-01

    Cosmic strings are linear topological defects that are predicted by some grand unified theories to form during a spontaneous symmetry breaking phase transition in the early universe. They are the basis for the only theories of galaxy formation aside from quantum fluctuations from inflation that are based on fundamental physics. In contrast to inflation, they can also be observed directly through gravitational lensing and their characteristic microwave background anistropy. It has recently been discovered by F. Bouchet and myself that details of cosmic string evolution are very different from the so-called ''standard model'' that has been assumed in most of the string induced galaxy formation calculations. Therefore, the details of galaxy formation in the cosmic string models are currently very uncertain. 29 refs., 9 figs

  7. Exact optics - III. Schwarzschild's spectrograph camera revised

    Science.gov (United States)

    Willstrop, R. V.

    2004-03-01

    Karl Schwarzschild identified a system of two mirrors, each defined by conic sections, free of third-order spherical aberration, coma and astigmatism, and with a flat focal surface. He considered it impractical, because the field was too restricted. This system was rediscovered as a quadratic approximation to one of Lynden-Bell's `exact optics' designs which have wider fields. Thus the `exact optics' version has a moderate but useful field, with excellent definition, suitable for a spectrograph camera. The mirrors are strongly aspheric in both the Schwarzschild design and the exact optics version.

  8. Spectrographic analysis of uranium-molybdenum alloys

    International Nuclear Information System (INIS)

    Roca, M.

    1967-01-01

    A spectrographic method of analysis has been developed for uranium-molybdenum alloys containing up to 10 % Mo. The carrier distillation technique, with gallium oxide and graphite as carriers, is used for the semiquantitative determination of Al, Cr, Fe, Ni and Si, involving the conversion of the samples into oxides. As a consequence of the study of the influence of the molybdenum on the line intensities, it is useful to prepare only one set of standards with 0,6 % MoO 3 . Total burning excitation is used for calcium, employing two sets of standards with 0,6 and 7.5 MoO 3 . (Author) 5 refs

  9. Constraints on the origin of cosmic rays above 10.sup.18./sup. eV from large-scale anisotropy searches in data of the Pierre Auger Observatory

    Czech Academy of Sciences Publication Activity Database

    Abreu, P.; Aglietta, M.; Ahlers, M.; Boháčová, Martina; Chudoba, Jiří; Ebr, Jan; Mandát, Dušan; Nečesal, Petr; Nožka, Libor; Palatka, Miroslav; Pech, Miroslav; Prouza, Michael; Řídký, Jan; Schovancová, Jaroslava; Schovánek, Petr; Trávníček, Petr; Vícha, Jakub

    2013-01-01

    Roč. 762, č. 1 (2013), s. 1-8 ISSN 2041-8205 R&D Projects: GA TA ČR TA01010517; GA MŠk(CZ) MEB111003; GA AV ČR KJB100100904; GA MŠk LA08015; GA MŠk(CZ) LA08016 Institutional research plan: CEZ:AV0Z10100502; CEZ:AV0Z10100522 Keywords : astroparticle physics * cosmic rays Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 5.602, year: 2013

  10. Study of the performance of the ATLAS muon spectrometer at LHC, from cosmic origin to collisions. Measurement of the WZ production cross-section

    International Nuclear Information System (INIS)

    Le Menedeu, E.

    2011-09-01

    ATLAS is one of the four experiments at the Large Hadron Collider (LHC), located at CERN, Geneva. As the LHC only delivered its first collisions in December 2009, at an energy of 7 TeV in the centre-of-mass, ATLAS recorded millions of cosmic events in 2008 and 2009 in order to better understand the detector. The first part of this PhD thesis deals with these cosmic events in order to estimate the muon spectrometer performances, particularly its efficiency and resolution. Next, using 7 TeV collisions, the efficiency is determined using a 'Tag and Probe' method on Z events decaying into muons. In addition, the missing transverse energy is studied and a clear improvement of its resolution is achieved through a better treatment of the muons. Finally, muons, missing transverse energy, but also electrons, are used to estimate the production cross-section of WZ di-bosons. Event selection, backgrounds estimation and systematics errors are provided. A computation of the WZ cross-section using 1.02 fb -1 of data is proposed: (21.1+3.1-2.8(sta)+1.2-1.2(syst)+0.9-0.8(lumi)) pb. A first estimation of the limits on anomalous triple gauge couplings have been deduced from the value of the cross-section: -0.21 l Z Z < 1.2 and -0.18 < λ < 0.18

  11. High-energy cosmic rays

    Energy Technology Data Exchange (ETDEWEB)

    Gaisser, Thomas K. [Bartol Research Institute, University of Delaware, Newark, DE 19716 (United States)]. E-mail: gaisser@bartol.udel.edu; Stanev, Todor [Bartol Research Institute, University of Delaware, Newark, DE 19716 (United States)

    2006-10-17

    After a brief review of galactic cosmic rays in the GeV to TeV energy range, we describe some current problems of interest for particles of very high energy. Particularly interesting are two features of the spectrum, the knee above 10{sup 15} eV and the ankle above 10{sup 18} eV. An important question is whether the highest-energy particles are of extra-galactic origin and, if so, at what energy the transition occurs. A theme common to all energy ranges is use of nuclear abundances as a tool for understanding the origin of the cosmic radiation.

  12. Micro photometer's automation for quantitative spectrograph analysis

    International Nuclear Information System (INIS)

    Gutierrez E, C.Y.A.

    1996-01-01

    A Microphotometer is used to increase the sharpness of dark spectral lines. Analyzing these lines one sample content and its concentration could be determined and the analysis is known as Quantitative Spectrographic Analysis. The Quantitative Spectrographic Analysis is carried out in 3 steps, as follows. 1. Emulsion calibration. This consists of gauging a photographic emulsion, to determine the intensity variations in terms of the incident radiation. For the procedure of emulsion calibration an adjustment with square minimum to the data obtained is applied to obtain a graph. It is possible to determine the density of dark spectral line against the incident light intensity shown by the microphotometer. 2. Working curves. The values of known concentration of an element against incident light intensity are plotted. Since the sample contains several elements, it is necessary to find a work curve for each one of them. 3. Analytical results. The calibration curve and working curves are compared and the concentration of the studied element is determined. The automatic data acquisition, calculation and obtaining of resulting, is done by means of a computer (PC) and a computer program. The conditioning signal circuits have the function of delivering TTL levels (Transistor Transistor Logic) to make the communication between the microphotometer and the computer possible. Data calculation is done using a computer programm

  13. Field Raman Spectrograph for Environmental Analysis

    International Nuclear Information System (INIS)

    Sylvia, J.M.; Haas, J.W.; Spencer, K.M.; Carrabba, M.M.; Rauh, R.D.; Forney, R.W.; Johnston, T.M.

    1998-01-01

    The widespread contamination found across the US Department of Energy (DOE) complex has received considerable attention from the government and public alike. A massive site characterization and cleanup effort has been underway for several years and is expected to continue for several decades more. The scope of the cleanup effort ranges from soil excavation and treatment to complete dismantling and decontamination of whole buildings. To its credit, DOE has supported research and development of new technologies to speed up and reduce the cost of this effort. One area in particular has been the development of portable instrumentation that can be used to perform analytical measurements in the field. This approach provides timely data to decision makers and eliminates the expense, delays, and uncertainties of sample preservation, transport, storage, and laboratory analysis. In this program, we have developed and demonstrated in the field a transportable, high performance Raman spectrograph that can be used to detect and identify contaminants in a variety of scenarios. With no moving parts, the spectrograph is rugged and can perform many Raman measurements in situ with flexible fiber optic sampling probes. The instrument operates under computer control and a software package has been developed to collect and process spectral data. A collection of Raman spectra for 200 contaminants of DOE importance has been compiled in a searchable format to assist in the identification of unknown contaminants in the field

  14. The deterministic optical alignment of the HERMES spectrograph

    Science.gov (United States)

    Gers, Luke; Staszak, Nicholas

    2014-07-01

    The High Efficiency and Resolution Multi Element Spectrograph (HERMES) is a four channel, VPH-grating spectrograph fed by two 400 fiber slit assemblies whose construction and commissioning has now been completed at the Anglo Australian Telescope (AAT). The size, weight, complexity, and scheduling constraints of the system necessitated that a fully integrated, deterministic, opto-mechanical alignment system be designed into the spectrograph before it was manufactured. This paper presents the principles about which the system was assembled and aligned, including the equipment and the metrology methods employed to complete the spectrograph integration.

  15. LRS2: A New Integral Field Spectrograph for the HET

    Science.gov (United States)

    Tuttle, Sarah E.; Hill, Gary J.; Chonis, Taylor S.; Tonnesen, Stephanie

    2016-01-01

    Here we present LRS2 (Low Resolution Spectrograph) and highlight early science opportunities with the newly upgraded Hobby Eberly telescope (HET). LRS2 is a four-channel optical wavelength (370nm - 1micron) spectrograph based on two VIRUS unit spectrographs. This fiber-fed integral field spectrograph covers a 12" x 6" field of view, switched between the two units (one blue, and one red) at R~2000. We highlight design elements, including the fundamental modification to grisms (from VPH gratings in VIRUS) to access the higher resolution. We discuss early science opportunities, including investigating nearby "blue-bulge" spiral galaxies and their anomalous star formation distribution.

  16. Cosmic Ether

    CERN Document Server

    Tomaschitz, R

    1998-01-01

    A prerelativistic approach to particle dynamics is explored in an expanding Robertson-Walker cosmology. The receding galactic background provides a distinguished frame of reference and a unique cosmic time. In this context the relativistic, purely geometric space-time concept is criticized. Physical space is regarded as a permeable medium, the cosmic ether, which effects the world-lines of particles and rays. We study in detail a Robertson-Walker universe with linear expansion factor and negatively curved, open three-space; we choose the permeability tensor of the ether in such a way that the semiclassical approximation is exact. Galactic red-shifts depend on the refractive index of the ether. In the local Minkowskian limit the ether causes a time variation of mass, which scales inversely proportional to cosmic time. In the globally geodesic rest frames of galactic observers the ether manifests itself in an unbounded speed of signal transfer, in bifurcations of world-lines, and in time inversion effects.

  17. Cosmic Topology

    Science.gov (United States)

    Luminet, Jean-Pierre

    2015-08-01

    Cosmic Topology is the name given to the study of the overall shape of the universe, which involves both global topological features and more local geometrical properties such as curvature. Whether space is finite or infinite, simply-connected or multi-connected like a torus, smaller or greater than the portion of the universe that we can directly observe, are questions that refer to topology rather than curvature. A striking feature of some relativistic, multi-connected "small" universe models is to create multiples images of faraway cosmic sources. While the most recent cosmological data fit the simplest model of a zero-curvature, infinite space model, they are also consistent with compact topologies of the three homogeneous and isotropic geometries of constant curvature, such as, for instance, the spherical Poincaré Dodecahedral Space, the flat hypertorus or the hyperbolic Picard horn. After a "dark age" period, the field of Cosmic Topology has recently become one of the major concerns in cosmology, not only for theorists but also for observational astronomers, leaving open a number of unsolved issues.

  18. Cosmic antimatter

    International Nuclear Information System (INIS)

    Tarle, G.; Swordy, S.

    1998-01-01

    In 1928 Paul Dirac forecasted the existence of antimatter and 4 years later Carl Anderson detected the first antiparticle: the positron in a cloud chamber while studying cosmic radiation. Antiprotons were more difficult to find but in 1955 physicists from Lawrence Berkeley Laboratory got some in a particle accelerator. In 1995 a team from the CERN synthesized atoms of anti-hydrogen by binding positrons to antiprotons in a particle accelerator. Astrophysicists have built more and more complex detectors to study cosmic rays. The detector HEAT (high energy antimatter telescope) has been designed to study positrons above the atmosphere. This detector has been launched for the first time in 1994 and has measured cosmic radiation for 32 hours at an altitude of 37000 meters. The results were challenging: whereas the number of low energy positrons detected agrees with the theory, the number of high energy positrons is too important. It suggests the existence of unknown sources of positrons somewhere in the universe. The massive particles that interact weakly (WIMP) could be such sources. This article draws the history of the quest for antimatter and its implications in cosmology, the detector HEAT is described. (A.C.)

  19. Study of an integral field spectrograph for the SNAP satellite. Prototype, simulation and performances

    International Nuclear Information System (INIS)

    Aumeunier, Marie-Helene

    2007-01-01

    The SNAP (Supernovae/Acceleration Probe) project plans to measure very precisely the cosmological parameters and to determine the nature of dark energy by observations of type Ia supernovae and weak lensing. The SNAP instrument consists in a 2-meter telescope with a one square-degree imager and a spectrograph in the visible and infrared range. A dedicated optimized integral field spectrograph based on an imager slicer technology has been developed. To test and validate the performances, two approaches have been developed: a complete simulation of the complete instrument at the pixel level and the manufacturing and test of a spectrograph prototype operating at room temperature and in cryogenic environment. In this thesis we will test the optical and functional performances of the SNAP spectrograph: especially diffraction losses, stray-light and spectro-photometric calibration. We present an original approach for the spectro-photometric calibration adapted for the slicer and the optical performances resulting from the first measurement campaign in the visible range. (author) [fr

  20. Cosmic Rays Astrophysics: The Discipline, Its Scope, and Its Applications

    Science.gov (United States)

    Barghouty, A. F.

    2009-01-01

    This slide presentation gives an overview of the discipline surrounding cosmic ray astrophysics. It includes information on recent assertions surrounding cosmic rays, exposure levels, and a short history with specific information on the origin, acceleration, transport, and modulation of cosmic rays.

  1. Interpreting the cosmic ray composition

    International Nuclear Information System (INIS)

    O'C Drury, L.; Ellisson, D.C; Meyer, J.-P.

    2000-01-01

    The detailed pattern of elemental abundances in the Galactic Cosmic Rays is well determined at energies of a few GeV per nucleon. After correction for propagation effects the inferred source composition shows significant deviations from the standard pattern of Galactic elemental abundances. These deviations, surprisingly overabundances of the heavy elements relative to Hydrogen, are clearly a significant clue to the origin of the cosmic rays, but one which has proven very difficult to interpret. We have recently shown that the 'standard' model for the origin of the bulk of the Galactic cosmic rays, namely acceleration by the diffusive shock acceleration process at the strong shocks associated with supernova remnants, can quantitatively explain all features of the source composition if the acceleration occurs from a dusty interstellar medium. This success must be regarded as one of the stronger pieces of evidence in favour of the standard model

  2. Interpreting the cosmic ray composition

    Energy Technology Data Exchange (ETDEWEB)

    O' C Drury, L.; Ellisson, D.C; Meyer, J.-P

    2000-01-31

    The detailed pattern of elemental abundances in the Galactic Cosmic Rays is well determined at energies of a few GeV per nucleon. After correction for propagation effects the inferred source composition shows significant deviations from the standard pattern of Galactic elemental abundances. These deviations, surprisingly overabundances of the heavy elements relative to Hydrogen, are clearly a significant clue to the origin of the cosmic rays, but one which has proven very difficult to interpret. We have recently shown that the 'standard' model for the origin of the bulk of the Galactic cosmic rays, namely acceleration by the diffusive shock acceleration process at the strong shocks associated with supernova remnants, can quantitatively explain all features of the source composition if the acceleration occurs from a dusty interstellar medium. This success must be regarded as one of the stronger pieces of evidence in favour of the standard model.

  3. Spectrographic determination of chlorine and fluorine

    International Nuclear Information System (INIS)

    Contamin, G.

    1965-04-01

    Experimental conditions have been investigated in order to obtain the highest sensitivity in spectrographic determination of chlorine and fluorine using the Fassel method of excitation in an inert atmosphere. The influence of the nature of the atmosphere, of the discharge conditions and of the matrix material has been investigated. The following results have been established: 1. chlorine determination is definitely possible: a working curve has been drawn between 10 μg and 100 μg, the detection limit being around 5 μg; 2. fluorine determination is not satisfactory: the detection limit is still of the order of 80 μg. The best operating conditions have been defined for both elements. (author) [fr

  4. Spectrographic determination of impurities in magnesium metal

    International Nuclear Information System (INIS)

    Capdevila, C.; Diaz-Guerra, J. P.

    1979-01-01

    The spectrographic determination of trace quantities of Al, B, Cd, Co, Cr, Cu, Fe, Li, Hn, Mo, Ni and Si in magnesium metal is described. Samples are dissolved with HNO 3 and calcinate into MgO. In order to avoid losses of boron NH 4 OH is added to the nitric solution. Except for aluminium and chromium the analysis is performed through the use of the carrier distillation technique. These two impurities are determined by burning to completion the MgO. Among the compounds studied as carriers (AgCl, AgF, CsCl, CuF 2 , KCl and SrF 2 ) AgCl allows, In general, the best volatilization efficiency. Lithium determination is achieved by using KC1 or CsCl. Detection limits, on the basis of MgO, are in the range 0,1 to 30 ppm, depending on the element. (Author) 8 refs

  5. Quantitative spectrographic analysis of impurities in antimonium

    International Nuclear Information System (INIS)

    Brito, J. de; Gomes, R.P.

    1978-01-01

    An emission spectrographic method is describe for the determination of Ag, Al, As, Be, Bi, Cd, Cr, Cu, Ga, Ni, Pb, Sn, Si, and Zn in high purity antimony metal. The metal sample ia dissolved in nitric acid(1:1) and converted tp oxide by calcination at 900 0 C for one hour. The oxide so obtained is mixed with graphite, which is used as a spectroscopic buffer, and excited by a direct current arc. Many parameters are studied optimum conditions are selected for the determination of the impurities mentioned. The spectrum is photographed in the second order of a 15.000 lines per inch grating and the most sensitive lines for the elements are selected. The impurities are determined in the concentration range of 1 - 0,01% with a precision of approximately 10% [pt

  6. Spectrographic determination of impurities in beryllium oxide

    International Nuclear Information System (INIS)

    Paula Reino, L.C. de; Lordello, A.R.; Pereira, A.S.A.

    1986-03-01

    A method for the spectrographic determination of Al, B, Cd, Co, Cu, Cr, Fe, Mg, NaNi, Si and Zn in nuclear grade beryllium oxide has been developed. The determination of Co, Al, Na and Zn is besed upon a carrier distillation technique. Better results were obtained with 2% Ga 2 O 3 as carrier in beryllium oxide. For the elements B, Cd, Cu, Fe, Cr, Mg, Ni and Si the sample is loaded in a Scribner-Mullin shallow cup electrode, covered with graphite powder and excited in DC arc. The relative standard deviation values for different elements are in the range of 10 to 20%. The method fulfills requirements of precision and sensitivity for specification analysis of nuclear grade beryllium oxide.(Author) [pt

  7. Field Raman spectrograph for environmental analysis

    International Nuclear Information System (INIS)

    Haas, J.W. III; Forney, R.W.; Carrabba, M.M.; Rauh, R.D.

    1995-01-01

    The enormous cost for chemical analysis at DOE facilities predicates that cost-saving measures be implemented. Many approaches, ranging from increasing laboratory sample throughput by reducing preparation time to the development of field instrumentation, are being explored to meet this need. Because of the presence of radioactive materials at many DOE sites, there is also a need for methods that are safer for site personnel and analysts. This project entails the development of a compact Raman spectrograph for field screening and monitoring of a wide variety of wastes, pollutants, and corrosion products in storage tanks, soils, and ground and surface waters. Analytical advantages of the Raman technique include its ability to produce a unique, spectral fingerprint for each contaminant and its ability to analyze both solids and liquids directly, without the need for isolation or cleanup

  8. Fiber Scrambling for High Precision Spectrographs

    Science.gov (United States)

    Kaplan, Zachary; Spronck, J. F. P.; Fischer, D.

    2011-05-01

    The detection of Earth-like exoplanets with the radial velocity method requires extreme Doppler precision and long-term stability in order to measure tiny reflex velocities in the host star. Recent planet searches have led to the detection of so called "super-Earths” (up to a few Earth masses) that induce radial velocity changes of about 1 m/s. However, the detection of true Earth analogs requires a precision of 10 cm/s. One of the largest factors limiting Doppler precision is variation in the Point Spread Function (PSF) from observation to observation due to changes in the illumination of the slit and spectrograph optics. Thus, this stability has become a focus of current instrumentation work. Fiber optics have been used since the 1980's to couple telescopes to high-precision spectrographs, initially for simpler mechanical design and control. However, fiber optics are also naturally efficient scramblers. Scrambling refers to a fiber's ability to produce an output beam independent of input. Our research is focused on characterizing the scrambling properties of several types of fibers, including circular, square and octagonal fibers. By measuring the intensity distribution after the fiber as a function of input beam position, we can simulate guiding errors that occur at an observatory. Through this, we can determine which fibers produce the most uniform outputs for the severest guiding errors, improving the PSF and allowing sub-m/s precision. However, extensive testing of fibers of supposedly identical core diameter, length and shape from the same manufacturer has revealed the "personality” of individual fibers. Personality describes differing intensity patterns for supposedly duplicate fibers illuminated identically. Here, we present our results on scrambling characterization as a function of fiber type, while studying individual fiber personality.

  9. Spectrographic analysis of thorium and its compounds

    International Nuclear Information System (INIS)

    Grampurohit, S.V.; Saksena, M.D.; Kaimal, V.N.P.; Kapoor, S.K.; Murty, P.S.

    1980-01-01

    A spectrographic method, which employs the principle of carrier-distillation technique, is described for the analysis of high purity thoria. Two carriers, AgCl and NaF were used in determining 27 trace elements in ThO 2 . The elements were divided into three groups, A, B and C. In group A, 15 elements, viz. Al, B, Be, Cd, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sb, Si and Sn were included since it was possible to choose sensitive lines of these elements in one spectral region, 220 - 285 nm. Group B covered 8 elements, viz. Ag, Bi, Ca, Ga, Mo, Ti, V and Zn, which could be determined in the spectral region 290 - 352.5 nm. Group C consisted 4 elements, viz. Ba, K, Li and Na which could be determined in the spectral region 440 - 820 nm. 5% AgCl was used as the carrier for the determination of groups A and C elements and 4% NaF was used as the carrier for the estimation of group B elements. One hundred milligrammes of the sample (in the form of ThO 2 ) containing the carrier were taken in a carrier-distillation electrode and excited in a d.c. arc (10 amps for groups A and C; 15 amps for group B). The spectra of sample and synthetic standards were photographed on Hilger's large quartz, JACO 3.4 m Ebert plane grating and Higler's large glass spectrographs respectively for determining group A, B and C elements. The detection limit obtained for B and Cd was 0.1 ppm. Thorium metal and thorium nitrate samples were converted to ThO 2 prior to analysis. (auth.)

  10. Cosmic Connections

    CERN Document Server

    Ellis, Jonathan Richard

    2003-01-01

    A National Research Council study on connecting quarks with the cosmos has recently posed a number of the more important open questions at the interface between particle physics and cosmology. These questions include the nature of dark matter and dark energy, how the Universe began, modifications to gravity, the effects of neutrinos on the Universe, how cosmic accelerators work, and whether there are new states of matter at high density and pressure. These questions are discussed in the context of the talks presented at this Summer Institute.

  11. First light results from the Hermes spectrograph at the AAT

    NARCIS (Netherlands)

    Sheinis, A.; Barden, S.; Birchall, M.; Carollo, D.; Bland-Hawthorn, J.; Brzeski, J.; Case, S.; Cannon, R.; Churilov, V.; Couch, W.; Dean, R.; De Silva, G.; D'Orazi, V.; Farrell, T.; Fiegert, K.; Freeman, K.; Frost, G.; Gers, L.; Goodwin, M.; Gray, D.; Heald, R.; Heijmans, J.A.C.; Jones, D.; Keller, S.; Klauser, U.; Kondrat, Y.; Lawrence, J.; Lee, S.; Mali, S.; Martell, S.; Mathews, D.; Mayfield, D.; Miziarski, S.; Muller, R.; Pai, N.; Patterson, R.; Penny, E.; Orr, D.; Shortridge, K.; Simpson, J.; Smedley, S.; Smith, G.; Stafford, D.; Staszak, N.; Vuong, M.; Waller, L.; Wylie de Boer, E.; Xavier, P.; Zheng, J.; Zhelem, R.; Zucker, D.

    2014-01-01

    The High Efficiency and Resolution Multi Element Spectrograph, HERMES is an facility-class optical spectrograph for the AAT. It is designed primarily for Galactic Archeology [21], the first major attempt to create a detailed understanding of galaxy formation and evolution by studying the history of

  12. Quantitative imaging through a spectrograph. 1. Principles and theory.

    NARCIS (Netherlands)

    Tolboom, R.A.L.; Dam, N.J.; Meulen, J.J. ter; Mooij, J.M.; Maassen, J.D.M.

    2004-01-01

    Laser-based optical diagnostics, such as planar laser-induced fluorescence and, especially, Raman imaging, often require selective spectral filtering. We advocate the use of an imaging spectrograph with a broad entrance slit as a spectral filter for two-dimensional imaging. A spectrograph in this

  13. Magnetic spectrograph for the Holifield heavy ion research facility

    International Nuclear Information System (INIS)

    Ford, J.L.C. Jr.; Enge, H.A.; Erskine, J.R.; Hendrie, D.L.; LeVine, M.J.

    1977-01-01

    The need for a new generation magnetic spectrograph for the Holifield Heavy Ion Research Facility is discussed. The advantages of a magnetic spectrograph for heavy ion research are discussed, as well as some of the types of experiments for which such an instrument is suited. The limitations which the quality of the incident beam, target and spectrograph itself impose on high resolution heavy ion measurements are discussed. Desired features of an ideal new spectrograph are: (1) intrinsic resolving power E/ΔE greater than or equal to 3000; (2) maximum solid angle greater than or equal to 20 msr; (3) dispersion approx. 4-8m; (4) maximum energy interval approx. 30%; and (5) mass-energy product greater than or equal to 200. Various existing and proposed spectrographs are compared with the specifications for a new heavy ion magnet design

  14. Meteors, meteorites and cosmic dust

    International Nuclear Information System (INIS)

    Lebedinets, V.N.

    1987-01-01

    The problem of meteorite origin and meteorite composition is discussed. Nowadays, most scientists suppose that the giant Oort cloud consisting of ice comet nuclei is the sourse of the meteor matter. A principle unity of the matter of meteorites falling to the Earth and cosmic dust is noted as well as that of meteorite bodies evaporating in the atmosphere and bearing meteors and bodies

  15. Garden of cosmic speculation

    CERN Document Server

    Jencks, Charles

    2005-01-01

    This book tells the story of one of the most important gardens in Europe, created by the architectural critic and designer Charles Jencks and his late wife, the landscape architect and author Maggie Keswick. The Garden of Cosmic Speculation is a landscape that celebrates the new sciences of complexity and chaos theory and consists of a series of metaphors exploring the origins, the destiny and the substance of the Universe. The book is illustrated with year-round photography, bringing the garden's many dimensions vividly to life.

  16. Cosmic Complexity

    Science.gov (United States)

    Mather, John C.

    2012-01-01

    neutrons, liberating a little energy and creating complexity. Then, the expanding universe cooled some more, and neutrons and protons, no longer kept apart by immense temperatures, found themselves unstable and formed helium nuclei. Then, a little more cooling, and atomic nuclei and electrons were no longer kept apart, and the universe became transparent. Then a little more cooling, and the next instability began: gravitation pulled matter together across cosmic distances to form stars and galaxies. This instability is described as a "negative heat capadty" in which extracting energy from a gravitating system makes it hotter -- clearly the 2nd law of thermodynamics does not apply here! (This is the physicist's part of the answer to e e cummings' question: what is the wonder that's keeping the stars apart?) Then, the next instability is that hydrogen and helium nuclei can fuse together to release energy and make stars burn for billions of years. And then at the end of the fuel source, stars become unstable and explode and liberate the chemical elements back into space. And because of that, on planets like Earth, sustained energy flows support the development of additional instabilities and all kinds of complex patterns. Gravitational instability pulls the densest materials into the core of the Earth, leaving a thin skin of water and air, and makes the interior churn incessantly as heat flows outwards. And the heat from the sun, received mostly near the equator and flowing towards the poles, supports the complex atmospheric and oceanic circulations. And because or that, the physical Earth is full of natural chemical laboratories, concentrating elements here, mixing them there, raising and lowering temperatures, ceaselessly experimenting with uncountable events where new instabilities can arise. At least one of them was the new experiment called life. Now that we know that there are at least as many planets as there are stars, it is hard to imagine that nature's ceasess

  17. Origins Space Telescope: Cosmology and Reionization

    Science.gov (United States)

    Vieira, Joaquin Daniel; Origins Space Telescope

    2018-01-01

    The Origins Space Telescope (OST) is the mission concept for the Far-Infrared Surveyor, a study in development by NASA in preparation for the 2020 Astronomy and Astrophysics Decadal Survey. Origins is planned to be a large aperture, actively-cooled telescope covering a wide span of the mid- to far-infrared spectrum. Its imagers and spectrographs will enable a variety of surveys of the sky that will discover and characterize the most distant galaxies, Milky-Way, exoplanets, and the outer reaches of our Solar system. Origins will enable flagship-quality general observing programs led by the astronomical community in the 2030s. The Science and Technology Definition Team (STDT) would like to hear your science needs and ideas for this mission. The team can be contacted at firsurveyor_info@lists.ipac.caltech.edu.A core science goal of the OST mission is to study the the cosmological history of star, galaxy, and structure formation into the epoch of reionization (EoR). OST will probe the birth of galaxies through warm molecular hydrogen emission during the cosmic dark ages. Utilizing the unique power of the infrared fine-structure emission lines, OST will trace the rise of metals from the first galaxies until today. It will quantify the dust enrichment history of the Universe, uncover its composition and physical conditions, reveal the first cosmic sources of dust, and probe the properties of the earliest star formation. OST will provide a detailed astrophysical probe into the condition of the intergalactic medium at z > 6 and the galaxies which dominate the epoch of reionization.

  18. Cosmic ray riddle solved?

    International Nuclear Information System (INIS)

    Anon.

    1995-01-01

    Full text: Physicists from Japan and the United States have discovered a possible answer to the puzzle of the origin of high energy cosmic rays that bombard Earth from all directions in space. Using data from the Japanese/US X-ray astronomical satellite ASCA, physicists have found strong evidence for the production of cosmic particles in the shock wave of a supernova remnant, the expanding fireball produced by the explosion of a star. Primary cosmic rays, mostly electrons and protons, travel near the speed of light. Each second, approximately 4 such particles cross one square centimetre of space just outside the Earth's atmosphere. Subsequently, collisions of these primary particles with atoms in the upper atmosphere produce slower secondary particles. Ever since the discovery of cosmic rays early this century, scientists have debated the origin of these particles and how they can be accelerated to such high speeds. Supernova remnants have long been thought to provide the high energy component, but the evidence has been lacking until now. The international team of investigators used the satellite to determine that cosmic rays are generated profusely in the remains of the supernova of 1006 AD - which appeared to medieval viewers to be as bright as the Moon - and that they are accelerated to high velocities by an iterative process first suggested by Enrico Fermi in 1949. Using solid-state X-ray cameras, the ASCA satellite records simultaneous images and spectra of X-rays from celestial sources, allowing astronomers to distinguish different types of X-ray emission. The tell-tale clue to the discovery was the detection of two diametrically opposite regions in the rapidly expanding supernova remnant, the debris from the stellar explosion. The two regions glow intensely from the synchrotron radiation produced when fast-moving electrons are bent by a magnetic field. The remainder of the supernova remnant, in contrast, emits ordinary ''thermal'' X

  19. Rocket studies of solar corona and transition region. [X-Ray spectrometer/spectrograph telescope

    Science.gov (United States)

    Acton, L. W.; Bruner, E. C., Jr.; Brown, W. A.; Nobles, R. A.

    1979-01-01

    The XSST (X-Ray Spectrometer/Spectrograph Telescope) rocket payload launched by a Nike Boosted Black Brant was designed to provide high spectral resolution coronal soft X-ray line information on a spectrographic plate, as well as time resolved photo-electric records of pre-selected lines and spectral regions. This spectral data is obtained from a 1 x 10 arc second solar region defined by the paraboloidal telescope of the XSST. The transition region camera provided full disc images in selected spectral intervals originating in lower temperature zones than the emitting regions accessible to the XSST. A H-alpha camera system allowed referencing the measurements to the chromospheric temperatures and altitudes. Payload flight and recovery information is provided along with X-ray photoelectric and UV flight data, transition camera results and a summary of the anomalies encountered. Instrument mechanical stability and spectrometer pointing direction are also examined.

  20. The Oxford SWIFT integral field spectrograph

    Science.gov (United States)

    Thatte, Niranjan; Tecza, Matthias; Clarke, Fraser; Goodsall, Timothy; Lynn, James; Freeman, David; Davies, Roger L.

    2006-06-01

    We present the design of the Oxford SWIFT integral field spectrograph, a dedicated I and z band instrument (0.65μm micron - 1.0μm micron at R~4000), designed to be used in conjunction with the Palomar laser guide star adaptive optics system (PALAO, and its planned upgrade PALM-3000). It builds on two recent developments (i) the improved ability of second generation adaptive optics systems to correct for atmospheric turbulence at wavelengths less than or equal to 1μm micron, and (ii) the availability of CCD array detectors with high quantum efficiency at very red wavelengths (close to the silicon band edge). Combining these with a state-of-the-art integral field unit design using an all-glass image slicer, SWIFT's design provides very high throughput and low scattered light. SWIFT simultaneously provides spectra of ~4000 spatial elements, arranged in a rectangular field-of-view of 44 × 89 pixels. It has three on-the-fly selectable pixel scales of 0.24", 0.16" and 0.08'. First light is expected in spring 2008.

  1. Vacuum Predisperser For A Large Plane-Grating Spectrograph

    Science.gov (United States)

    Engleman, R.; Palmer, B. A.; Steinhaus, D. W.

    1980-11-01

    A plane grating predisperser has been constructed which acts as an "order-sorter" for a large plane-grating spectrograph. This combination can photograph relatively wide regions of spectra in a single exposure with no loss of resolution.

  2. An integral field spectrograph utilizing mirrorlet arrays

    Science.gov (United States)

    Chamberlin, Phillip C.; Gong, Qian

    2016-09-01

    An integral field spectrograph (IFS) has been developed that utilizes a new and novel optical design to observe two spatial dimensions simultaneously with one spectral dimension. This design employs an optical 2-D array of reflecting and focusing mirrorlets. This mirrorlet array is placed at the imaging plane of the front-end telescope to generate a 2-D array of tiny spots replacing what would be the slit in a traditional slit spectrometer design. After the mirrorlet in the optical path, a grating on a concave mirror surface will image the spot array and provide high-resolution spectrum for each spatial element at the same time; therefore, the IFS simultaneously obtains the 3-D data cube of two spatial and one spectral dimensions. The new mirrorlet technology is currently in-house and undergoing laboratory testing at NASA Goddard Space Flight Center. Section 1 describes traditional classes of instruments that are used in Heliophysics missions and a quick introduction to the new IFS design. Section 2 discusses the details of the most generic mirrorlet IFS, while section 3 presents test results of a lab-based instrument. An example application to a Heliophysics mission to study solar eruptive events in extreme ultraviolet wavelengths is presented in section 4 that has high spatial resolution (0.5 arc sec pixels) in the two spatial dimensions and high spectral resolution (66 mÅ) across a 15 Å spectral window. Section 4 also concludes with some other optical variations that could be employed on the more basic IFS for further capabilities of this type of instrument.

  3. An Integral Field Spectrograph Utilizing Mirrorlet Arrays

    Science.gov (United States)

    Chamberlin, Phillip C.; Gong, Qian

    2016-01-01

    An integral field spectrograph (IFS) has been developed that utilizes a new and novel optical design to observe two spatial dimensions simultaneously with one spectral dimension. This design employs an optical 2-D array of reflecting and focusing mirrorlets. This mirrorlet array is placed at the imaging plane of the front-end telescope to generate a 2-D array of tiny spots replacing what would be the slit in a traditional slit spectrometer design. After the mirrorlet in the optical path, a grating on a concave mirror surface will image the spot array and provide high-resolution spectrum for each spatial element at the same time; therefore, the IFS simultaneously obtains the 3-D data cube of two spatial and one spectral dimensions. The new mirrorlet technology is currently in-house and undergoing laboratory testing at NASA Goddard Space Flight Center. Section 1 describes traditional classes of instruments that are used in Heliophysics missions and a quick introduction to the new IFS design. Section 2 discusses the details of the most generic mirrorlet IFS, while section 3 presents test results of a lab-based instrument. An example application to a Heliophysics mission to study solar eruptive events in extreme ultraviolet wavelengths is presented in section 4 that has high spatial resolution (0.5 arc sec pixels) in the two spatial dimensions and high spectral resolution (66 m) across a 15 spectral window. Section 4 also concludes with some other optical variations that could be employed on the more basic IFS for further capabilities of this type of instrument.

  4. Cosmic odyssey

    International Nuclear Information System (INIS)

    Heidmann, J.

    1989-01-01

    The immensity of the cosmos, the richness of the universe, the limits of space and time: these are the themes of Cosmic Odyssey, which takes the reader on imaginary journeys through the past, present and future of our universe. After a first look at the starry night sky, the enigmas posed since ancient times by the universe are reviewed. There then follows a broadbrush view of the universe as we understand it today. Following this, a trio of chapters take us to ultimate questions about its nature. The author explores in turn the relativistic universe, the quantum universe and the inflationary universe. Finally the journey returns to questions that touch on our own presence in the universe. Cosmology, the science of understanding the nature of the universe as a whole, has gone through an extraordinary revolution in its approach. This book explains in detail the link between particle physics and cosmology, the very early universe, the significance of Grand Unified Theory and superstrings, the magical qualities of the inflationary universe, and the seemingly bleak scenarios for the farthest future. (author)

  5. New Results from Fermi-LAT and Their Implications for the Nature of Dark Matter and the Origin of Cosmic Rays

    Science.gov (United States)

    Moiseev, Alexander

    2009-01-01

    The measured spectrum is compatible with a power law within our current systematic errors. The spectral index (-3.04) is harder than expected from previous experiments and simple theoretical considerations. "Pre-Fermi" diffusive model requires a harder electron injection spectrum (by 0.12) to fit the Fermi data, but inconsistent with positron excess reported by Pamela if it extends to higher energy. Additional component of electron flux from local source(s) may solve the problem; its origin, astrophysical or exotic, is still unclear. Valuable contribution to the calculation of IC component of diffuse gamma radiation.

  6. Multiradionuclide evidence for the solar origin of the cosmic-ray events of ᴀᴅ 774/5 and 993/4.

    Science.gov (United States)

    Mekhaldi, Florian; Muscheler, Raimund; Adolphi, Florian; Aldahan, Ala; Beer, Jürg; McConnell, Joseph R; Possnert, Göran; Sigl, Michael; Svensson, Anders; Synal, Hans-Arno; Welten, Kees C; Woodruff, Thomas E

    2015-10-26

    The origin of two large peaks in the atmospheric radiocarbon ((14)C) concentration at AD 774/5 and 993/4 is still debated. There is consensus, however, that these features can only be explained by an increase in the atmospheric (14)C production rate due to an extraterrestrial event. Here we provide evidence that these peaks were most likely produced by extreme solar events, based on several new annually resolved (10)Be measurements from both Arctic and Antarctic ice cores. Using ice core (36)Cl data in pair with (10)Be, we further show that these solar events were characterized by a very hard energy spectrum with high fluxes of solar protons with energy above 100 MeV. These results imply that the larger of the two events (AD 774/5) was at least five times stronger than any instrumentally recorded solar event. Our findings highlight the importance of studying the possibility of severe solar energetic particle events.

  7. Testing Cosmic Inflation

    Science.gov (United States)

    Chuss, David

    2010-01-01

    The Cosmic Microwave Background (CMB) has provided a wealth of information about the history and physics of the early Universe. Much progress has been made on uncovering the emerging Standard Model of Cosmology by such experiments as COBE and WMAP, and ESA's Planck Surveyor will likely increase our knowledge even more. Despite the success of this model, mysteries remain. Currently understood physics does not offer a compelling explanation for the homogeneity, flatness, and the origin of structure in the Universe. Cosmic Inflation, a brief epoch of exponential expansion, has been posted to explain these observations. If inflation is a reality, it is expected to produce a background spectrum of gravitational waves that will leave a small polarized imprint on the CMB. Discovery of this signal would give the first direct evidence for inflation and provide a window into physics at scales beyond those accessible to terrestrial particle accelerators. I will briefly review aspects of the Standard Model of Cosmology and discuss our current efforts to design and deploy experiments to measure the polarization of the CMB with the precision required to test inflation.

  8. The Mitchell Spectrograph: Studying Nearby Galaxies with the VIRUS Prototype

    Directory of Open Access Journals (Sweden)

    Guillermo A. Blanc

    2013-01-01

    Full Text Available The Mitchell Spectrograph (a.k.a. VIRUS-P on the 2.7 m Harlan J. Smith telescope at McDonald Observatory is currently the largest field of view (FOV integral field unit (IFU spectrograph in the world (1.7′×1.7′. It was designed as a prototype for the highly replicable VIRUS spectrograph which consists of a mosaic of IFUs spread over a 16′ diameter FOV feeding 150 spectrographs similar to the Mitchell. VIRUS will be deployed on the 9.2 meter Hobby-Eberly Telescope (HET and will be used to conduct the HET Dark Energy Experiment (HETDEX. Since seeing first light in 2007 the Mitchell Spectrograph has been widely used, among other things, to study nearby galaxies in the local universe where their internal structure and the spatial distribution of different physical parameters can be studied in great detail. These observations have provided important insight into many aspects of the physics behind the formation and evolution of galaxies and have boosted the scientific impact of the 2.7 meter telescope enormously. Here I review the contributions of the Mitchell Spectrograph to the study of nearby galaxies, from the investigation the spatial distribution of dark matter and the properties of supermassive black holes, to the studies of the process of star formation and the chemical composition of stars and gas in the ISM, which provide important information regarding the formation and evolution of these systems. I highlight the fact that wide field integral field spectrographs on small and medium size telescopes can be powerful cost effective tools to study the astrophysics of galaxies. Finally I briefly discuss the potential of HETDEX for conducting studies on nearby galaxies. The survey parameters make it complimentary and competitive to ongoing and future surveys like SAMI and MANGA.

  9. ALICE Cosmic Ray Detector

    CERN Multimedia

    Fernandez Tellez, A; Martinez Hernandez, M; Rodriguez Cahuantzi, M

    2013-01-01

    The ALICE underground cavern provides an ideal place for the detection of high energy atmospheric muons coming from cosmic ray showers. ACORDE detects cosmic ray showers by triggering the arrival of muons to the top of the ALICE magnet.

  10. Diffuse Cosmic Infrared Background Radiation

    Science.gov (United States)

    Dwek, Eli

    2002-01-01

    The diffuse cosmic infrared background (CIB) consists of the cumulative radiant energy released in the processes of structure formation that have occurred since the decoupling of matter and radiation following the Big Bang. In this lecture I will review the observational data that provided the first detections and limits on the CIB, and the theoretical studies explaining the origin of this background. Finally, I will also discuss the relevance of this background to the universe as seen in high energy gamma-rays.

  11. Cosmic void clumps

    Science.gov (United States)

    Lares, M.; Luparello, H. E.; Garcia Lambas, D.; Ruiz, A. N.; Ceccarelli, L.; Paz, D.

    2017-10-01

    Cosmic voids are of great interest given their relation to the large scale distribution of mass and the way they trace cosmic flows shaping the cosmic web. Here we show that the distribution of voids has, in consonance with the distribution of mass, a characteristic scale at which void pairs are preferentially located. We identify clumps of voids with similar environments and use them to define second order underdensities. Also, we characterize its properties and analyze its impact on the cosmic microwave background.

  12. Cosmic Perspectives

    Science.gov (United States)

    Biswas, S. K.; Mallik, D. C. V.; Vishveshwara, C. V.

    2008-07-01

    1. Astronomy in ancient and medieval China Joseph Needham; 2. Indian astronomy: an historical perspective B. V. Subbarayappa; 3. Making of astronomy in ancient India Debiprasad Chattopadhyaya; 4. The impact of astronomy on the development of western science Jean-Claude Pecker; 5. Man and the Universe Hubert Reeves; 6. Understanding the Universe - challenges and directions in modern observational astronomy Harlan Smith, Jr: 7. Frontiers in cosmology Fred Hoyle; 8. Did the Universe originate in a big bang? Jayant Narlikar; 9. The dark matter problem Bernard Carr; 10. Geometry and the Universe C. V. Vishveshwara; 11. The origin and evolution of life Cyril Ponnamperuma; 12. The anthropic principle: self selection as an adjunct to natural selection Brandon Carter; 13. Astrology and science: an examination of the evidence Ivan Kelly, Roger Culver and Peter Loptson; 14. Astronomy and science fiction Allen Janis.

  13. What is cosmic radiation?

    International Nuclear Information System (INIS)

    2004-01-01

    The earth was indeed receiving ionizing radiations from the heavens. This cosmic radiation consists of particles travelling near the speed of light. It consists of two components, the first of which is permanent and of galactic origin, while the other is more sporadic, depending on the sun's activities. Natural land-based sources expose each of us to an average total dose of 2.4 mSv per year (source UNSCEAR). In addition, the human activities using ionizing radiation contribute to an average annual exposure of 1.4 mSv, originating primarily with medical activities ( radiodiagnostic and radiation therapy). Members of flights crew are subject to exposure. The total dose of cosmic radiation received is is directly proportional with the duration of exposure, and thus with the duration of the flight. Measurement taken on board aircraft during the 1990's showed that flight personnel (on long haul flights) receive an average dose of approximately the same magnitude as the one due to exposure to natural radioactivity in France. The damage caused by ionizing radiation depends on the quantity of energy released by radiation into the cells of each organ or tissue of the human body(exposure dose). For a given quantity of absorbed energy (dose expressed in Gray), the damage will vary according to the nature of the radiation and the affected organ. These effects are of two types: acute effects and deferred effects. Two measurements are essential for radiation protection: the measurements of the dose of radiation absorbed by the body and the assessment of the risk associated with the absorbed dose. Two units were thus created: the gray and the sievert. (N.C.)

  14. Cosmic Microwave Background Timeline

    Science.gov (United States)

    Cosmic Microwave Background Timeline 1934 : Richard Tolman shows that blackbody radiation in an will have a blackbody cosmic microwave background with temperature about 5 K 1955: Tigran Shmaonov anisotropy in the cosmic microwave background, this strongly supports the big bang model with gravitational

  15. AN INTERFACE REGION IMAGING SPECTROGRAPH FIRST VIEW ON SOLAR SPICULES

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, T. M. D.; De Pontieu, B.; Carlsson, M.; Hansteen, V. [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, NO-0315 Oslo (Norway); Tarbell, T. D.; Lemen, J.; Title, A.; Boerner, P.; Hurlburt, N.; Wülser, J. P.; Martínez-Sykora, J.; Kleint, L. [Lockheed Martin Solar and Astrophysics Laboratory, 3251 Hanover Street, Org. A021S, Bldg. 252, Palo Alto, CA 94304 (United States); Golub, L.; McKillop, S.; Reeves, K. K.; Saar, S.; Testa, P.; Tian, H. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Jaeggli, S.; Kankelborg, C., E-mail: tiago.pereira@astro.uio.no [Department of Physics, Montana State University, P.O. Box 173840, Bozeman, MT 59717 (United States)

    2014-09-01

    Solar spicules have eluded modelers and observers for decades. Since the discovery of the more energetic type II, spicules have become a heated topic but their contribution to the energy balance of the low solar atmosphere remains unknown. Here we give a first glimpse of what quiet-Sun spicules look like when observed with NASA's recently launched Interface Region Imaging Spectrograph (IRIS). Using IRIS spectra and filtergrams that sample the chromosphere and transition region, we compare the properties and evolution of spicules as observed in a coordinated campaign with Hinode and the Atmospheric Imaging Assembly. Our IRIS observations allow us to follow the thermal evolution of type II spicules and finally confirm that the fading of Ca II H spicules appears to be caused by rapid heating to higher temperatures. The IRIS spicules do not fade but continue evolving, reaching higher and falling back down after 500-800 s. Ca II H type II spicules are thus the initial stages of violent and hotter events that mostly remain invisible in Ca II H filtergrams. These events have very different properties from type I spicules, which show lower velocities and no fading from chromospheric passbands. The IRIS spectra of spicules show the same signature as their proposed disk counterparts, reinforcing earlier work. Spectroheliograms from spectral rasters also confirm that quiet-Sun spicules originate in bushes from the magnetic network. Our results suggest that type II spicules are indeed the site of vigorous heating (to at least transition region temperatures) along extensive parts of the upward moving spicular plasma.

  16. Spectroscopic Characterization of GEO Satellites with Gunma LOW Resolution Spectrograph

    Science.gov (United States)

    Endo, T.; Ono, H.; Hosokawa, M.; Ando, T.; Takanezawa, T.; Hashimoto, O.

    The spectroscopic observation is potentially a powerful tool for understanding the Geostationary Earth Orbit (GEO) objects. We present here the results of an investigation of energy spectra of GEO satellites obtained from a groundbased optical telescope. The spectroscopic observations were made from April to June 2016 with the Gunma LOW resolution Spectrograph and imager (GLOWS) at the Gunma Astronomical Observatory (GAO) in JAPAN. The observation targets consist of eleven different satellites: two weather satellites, four communications satellites, and five broadcasting satellites. All the spectra of those GEO satellites are inferred to be solar-like. A number of well-known absorption features such as H-alpha, H-beta, Na-D,water vapor and oxygen molecules are clearly seen in thewavelength range of 4,000 - 8,000 Å. For comparison, we calculated the intensity ratio of the spectra of GEO satellites to that of the Moon which is the natural satellite of the earth. As a result, the following characteristics were obtained. 1) Some variations are seen in the strength of absorption features of water vapor and oxygen originated by the telluric atmosphere, but any other characteristic absorption features were not found. 2) For all observed satellites, the intensity ratio of the spectrum of GEO satellites decrease as a function of wavelength or to be flat. It means that the spectral reflectance of satellite materials is bluer than that of the Moon. 3) A characteristic dip at around 4,800 Å is found in all observed spectra of a weather satellite. Based on these observations, it is indicated that the characteristics of the spectrum are mainly derived from the solar panels because the apparent area of the solar cell is probably larger than that of the satellite body.

  17. Cosmic Censorship for Gowdy Spacetimes.

    Science.gov (United States)

    Ringström, Hans

    2010-01-01

    Due to the complexity of Einstein's equations, it is often natural to study a question of interest in the framework of a restricted class of solutions. One way to impose a restriction is to consider solutions satisfying a given symmetry condition. There are many possible choices, but the present article is concerned with one particular choice, which we shall refer to as Gowdy symmetry. We begin by explaining the origin and meaning of this symmetry type, which has been used as a simplifying assumption in various contexts, some of which we shall mention. Nevertheless, the subject of interest here is strong cosmic censorship. Consequently, after having described what the Gowdy class of spacetimes is, we describe, as seen from the perspective of a mathematician, what is meant by strong cosmic censorship. The existing results on cosmic censorship are based on a detailed analysis of the asymptotic behavior of solutions. This analysis is in part motivated by conjectures, such as the BKL conjecture, which we shall therefore briefly describe. However, the emphasis of the article is on the mathematical analysis of the asymptotics, due to its central importance in the proof and in the hope that it might be of relevance more generally. The article ends with a description of the results that have been obtained concerning strong cosmic censorship in the class of Gowdy spacetimes.

  18. Cosmic gamma-ray background radiation. Current understandings and problems

    International Nuclear Information System (INIS)

    Inoue, Yoshiyuki

    2015-01-01

    The cosmic gamma-ray background radiation is one of the most fundamental observables in the gamma-ray band. Although the origin of the cosmic gamma-ray background radiation has been a mystery for a long time, the Fermi gamma-ray space telescope has recently measured it at 0.1-820 GeV and revealed that the cosmic GeV gamma-ray background is composed of blazars, radio galaxies, and star-forming galaxies. However, Fermi still leaves the following questions. Those are dark matter contribution, origins of the cosmic MeV gamma-ray background, and the connection to the IceCube TeV-PeV neutrino events. In this proceeding, I will review the current understandings of the cosmic gamma-ray background and discuss future prospects of cosmic gamma-ray background radiation studies. (author)

  19. Recording {gamma} spectrometer with elimination of compton background; Spectrographe {gamma} enregistreur avec elimination du bruit de fond compton

    Energy Technology Data Exchange (ETDEWEB)

    Julliot, C [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    This instrument, derived from the recording {gamma} spectrograph, gives better definition of photoelectric peaks by elimination of pulses caused by {gamma} photons incompletely absorbed in the scintillator (Compton effect). This system uses an original method devised by Peirson: the spectrum, devoid of photoelectric peak, supplied by a detector equipped with an anthracene scintillator, is cut off from the spectrum provided by a conventional detector equipped with a Nal (T1) scintillator. The regulation of the mechanical system, detector support and source allows the detection yields to be adjusted. The electronic system is identical in presentation with that of the recording spectrograph. (author) [French] Cet appareil derive du spectrographe {gamma} enregistreur permet d'obtenir une meilleure definition des pics photoelectriques, par elimination des impulsions provenant des photons {gamma} incompletement absorbes dans le scintillateur (effet Compton). Cet ensemble met en oeuvre une methode originale due a Peirson: le spectre, depourvu de pic photoelectrique, fourni par un detecteur, equipe avec un scintillateur d'anthracene, est retranche du spectre donne par un detecteur classique, equipe avec un scintillateur de NaI (T1). Le reglage de l'ensemble mecanique, support des detecteurs et de la source, permet d'ajuster les rendements de detection. L'ensemble electronique se presente sous un aspect identique a celui du spectrographe enregistreur. (auteur)

  20. Cosmic rays at ultra high energies (Neutrinos.)

    International Nuclear Information System (INIS)

    Ahlers, M.; Ringwald, A.; Tu, H.

    2005-06-01

    Resonant photopion production with the cosmic microwave background predicts a suppression of extragalactic protons above the famous Greisen-Zatsepin-Kuzmin cutoff at about E GZK ∼ 5 x 10 10 GeV. Current cosmic ray data measured by the AGASA and HiRes Collaborations do not unambiguously confirm the GZK cutoff and leave a window for speculations about the origin and chemical composition of the highest energy cosmic rays. In this work we analyze the possibility of strongly interacting neutrino primaries and derive model-independent quantitative requirements on the neutrino-nucleon inelastic cross section for a viable explanation of the cosmic ray data. Search results on weakly interacting cosmic particles from the AGASA and RICE experiments are taken into account simultaneously. Using a flexible parameterization of the inelastic neutrino-nucleon cross section we find that a combined fit of the data does not favor the Standard Model neutrino-nucleon inelastic cross section, but requires, at 90% confidence level, a steep increase within one energy decade around E GZK by four orders of magnitude. We illustrate such an enhancement within some extensions of the Standard Model. The impact of new cosmic ray data or cosmic neutrino search results on this scenario, notably from the Pierre Auger Observatory soon, can be immediately evaluated within our approach. (orig.)

  1. Cosmic plasma

    Energy Technology Data Exchange (ETDEWEB)

    Alfven, H [California Univ., San Diego, La Jolla (USA)

    1981-01-01

    The properties of space plasmas are analyzed, based on laboratory results and data obtained by in situ measurements in the magnetosphere (including the heliosphere). Attention is given to the question of how much knowledge can be gained by a systematic comparison of different regions of plasma, and plasmas are considered with linear dimensions varying from laboratory size up to the Hubble distance. The traditional magnetic field description of plasmas is supplemented by an electric current description and it is demonstrated that many problems are easier to understand with a dualistic approach. Using the general plasma properties obtained, the origin and evolution of the solar system is summarized and the evolution and present structure of the universe (cosmology) is discussed.

  2. Spectrographic Determination of Trace Constituents in Rare Earths

    International Nuclear Information System (INIS)

    Capdevila, C.; Alvarez, F.

    1962-01-01

    A spectrographic method was developed for the determination of 18 trace elements in lanthanum, cerium, praseodimium, neodimium and samarium compounds. The concentrations of the impurities cover the range of 0,5 to 500 ppm. Most of these impurities are determined by the carrier distillation method. Several more refractory elements have been determined by total burning of the sample with a direct current arc or by the conduction briquet excitation technique with a high voltage condensed spark. The work has been carried out with a Hilger Automatic Large Quartz Spectrograph. (Author) 5 refs

  3. Using a new, free spectrograph program to critically investigate acoustics

    Science.gov (United States)

    Ball, Edward; Ruiz, Michael J.

    2016-11-01

    We have developed an online spectrograph program with a bank of over 30 audio clips to visualise a variety of sounds. Our audio library includes everyday sounds such as speech, singing, musical instruments, birds, a baby, cat, dog, sirens, a jet, thunder, and screaming. We provide a link to a video of the sound sources superimposed with their respective spectrograms in real time. Readers can use our spectrograph program to view our library, open their own desktop audio files, and use the program in real time with a computer microphone.

  4. Lead shielded cells for the spectrographic analysis of radioisotope solutions

    International Nuclear Information System (INIS)

    Roca, M.; Capdevila, C.; Cruz, F. de la

    1967-01-01

    Two lead shielded cells for the spectrochemical analysis of radioisotope samples are described. One of them is devoted to the evaporation of samples before excitation and the other one contains a suitable spectrographic excitation stand for the copper spark technique. A special device makes it possible the easy displacement of the excitation cell on wheels and rails for its accurate and reproducible position as well as its replacement by a glove box for plutonium analysis. In order to guarantee safety the room in which the spectrograph and the source are set up in separated from the active laboratory by a wall with a suitable window. (Author) 1 refs

  5. Cosmic Humanity: Utopia, Realities, Prospects

    Directory of Open Access Journals (Sweden)

    Sergey Krichevsky

    2017-07-01

    Full Text Available The philosophical foundations of the theory and practice of the creation of cosmic humanity as a process of the evolution of human civilization, the emergence into space, with the prospect of resettlement outside the Earth are considered. There is a connection between myths, fantasies, ideas, concepts and projects aimed at the exploration of outer space, the creation of cosmic humanity. A new and voluminous definition of cosmic humanity in the evolutionary paradigm is given. Cosmic humanity is (essence and 4 stages of evolution: 1. Humanity living on Earth, sensing, knowing, understanding its cosmic origin, relationship with the cosmos and cosmic destiny. 2. Humanity living on Earth, leading aerospace activity for the purposes of exploration and use of aerospace space (Heaven, Space for survival and development. 3. Humanity living on Earth and outside the Earth — in the solar system, preserving the Earth and mastering the Cosmos for survival and development. 4. Humanity, settled and living in the Cosmos. Now humanity is in the process of transition from the second to the third stage. In the process of this evolution, a complex transformation of man and society takes place. The problem-semantic field of cosmic humanity is described and its general model is presented. The meta-goal-setting is the justification of cosmic humanity with the application of the anthropic principle and its “active” super (post anthropic supplement: “Cosmic humanity has an evolutionary purpose to actively manage evolution: change man, humanity and the universe.” The evolution of the “cosmic dream”, goals and technologies of space activities is formalized in the form of a conceptual model. Challenges and negative trends are considered in connection with the crisis of space activity, criticism and attempts to limit the flights of people into space. The prototype of cosmic humanity, its basis and acting model is the cosmonauts’ community. The main

  6. The ALTA cosmic ray experiment electronics system

    International Nuclear Information System (INIS)

    Brouwer, W.; Burris, W.J.; Caron, B.; Hewlett, J.; Holm, L.; Hamilton, A.; McDonald, W.J.; Pinfold, J.L.; Price, P.; Schaapman, J.R.; Sibley, L.; Soluk, R.A.; Wampler, L.J.

    2005-01-01

    Understanding the origin and propagation of high-energy cosmic rays is a fundamental area of astroparticle physics with major unanswered questions. The study of cosmic rays with energy more than 10 14 eV, probed only by ground-based experiments, has been restricted by the low particle flux. The Alberta Large-area Time-coincidence Array (ALTA) uses a sparse array of cosmic ray detection stations located in high schools across a large geographical area to search for non-random high-energy cosmic ray phenomena. Custom-built ALTA electronics is based on a modular board design. Its function is to control the detectors at each ALTA site allowing precise measurements of event timing and energy in the local detectors as well as time synchronization of all of the sites in the array using the global positioning system

  7. Cosmic ray antimatter and baryon symmetric cosmology

    Science.gov (United States)

    Stecker, F. W.; Protheroe, R. J.; Kazanas, D.

    1982-01-01

    The relative merits and difficulties of the primary and secondary origin hypotheses for the observed cosmic-ray antiprotons, including the new low-energy measurement of Buffington, et al. We conclude that the cosmic-ray antiproton data may be evidence for antimatter galaxies and baryon symmetric cosmology. The present bar P data are consistent with a primary extragalactic component having /p=/equiv 1+/- 3.2/0.7x10 = to the -4 independent of energy. We propose that the primary extragalactic cosmic ray antiprotons are most likely from active galaxies and that expected disintegration of bar alpha/alpha ban alpha/alpha. We further predict a value for ban alpha/alpha =/equiv 10 to the -5, within range of future cosmic ray detectors.

  8. Primary cosmic radiation

    International Nuclear Information System (INIS)

    Anderson, H.R.

    1972-01-01

    The term cosmic radiation means the charged particle flux that reaches the earth from outside its magnetosphere with energies above the solar wind energy of a few keV. There are two sources of flux. Sporadically the sun produces such particles, generally within the energy range 1--200 MeV, and these solar cosmic rays arrive at the earth for a period ranging from hours to days. There may be a small, rather constant flux from the sun also, but the bulk of the steady flux originates outside the earth's orbit. Although some have conjectured that part of this latter flux may be accelerated in the outer portions of the solar system where the outward flowing interplanetary medium meets the interstellar medium, it is generally thought that most or all of it arises in unique systems such as supernovae, and is distributed throughout the galaxy. These galactic particles range in energy from a few MeV to at least 10 13 MeV and consist primarily of protons with significant numbers of heavier nuclei, positrons and electrons. They are supposed to fill our galaxy, or at least the disc, more or less uniformly. However, the flux with energies below a few GeV that reaches earth's orbit is modulated by the interplanetary medium so that the number at earth varies inversely with solar activity and is always somewhat below the interstellar flux. A discussion is presented of primary galactic radiation at earth, its modulation by solar activity, and its interaction with the geomagnetic field. (U.S.)

  9. Cosmic Rays: studies and measurements before 1912

    Energy Technology Data Exchange (ETDEWEB)

    De Angelis, Alessandro [INFN and Università di Udine, Via delle Scienze 206, I-33100 Udine (Italy); LIP/IST Lisboa (Portugal)

    2013-06-15

    The discovery of cosmic rays, a milestone in science, was based on the work by scientists in Europe and the New World and took place during a period characterised by nationalism and lack of communication. Many scientists that took part in this research a century ago were intrigued by the penetrating radiation and tried to understand the origin of it. Several important contributions to the discovery of the origin of cosmic rays have been forgotten; historical, political and personal facts might have contributed to their substantial disappearance from the history of science.

  10. Cosmic Rays: studies and measurements before 1912

    Science.gov (United States)

    De Angelis, Alessandro

    2013-06-01

    The discovery of cosmic rays, a milestone in science, was based on the work by scientists in Europe and the New World and took place during a period characterised by nationalism and lack of communication. Many scientists that took part in this research a century ago were intrigued by the penetrating radiation and tried to understand the origin of it. Several important contributions to the discovery of the origin of cosmic rays have been forgotten; historical, political and personal facts might have contributed to their substantial disappearance from the history of science.

  11. Cosmic Rays: studies and measurements before 1912

    International Nuclear Information System (INIS)

    De Angelis, Alessandro

    2013-01-01

    The discovery of cosmic rays, a milestone in science, was based on the work by scientists in Europe and the New World and took place during a period characterised by nationalism and lack of communication. Many scientists that took part in this research a century ago were intrigued by the penetrating radiation and tried to understand the origin of it. Several important contributions to the discovery of the origin of cosmic rays have been forgotten; historical, political and personal facts might have contributed to their substantial disappearance from the history of science

  12. Galactic origin of cosmic rays II

    International Nuclear Information System (INIS)

    Colgate, S.A.

    1981-01-01

    The CR acceleration due to shocks in the ISM depends upon multiple crossings approx. = c/3 v/sub Alfven/ approx. = 10 4 per e-fold energy gain. The up-stream scattering required to produce this barrier is Alfven wave turbulence. When the ratio (CR pressure)/(B 2 /8π) identical = β > 1, the streaming velocity theoretically and observationally becomes >> v/sub Alfven/ and, hence, no effective up-stream barrier is likely to exist. If all ISM shock acceleration is limited to β approx. 10 13 to 10 14 eV. It is usually assumed that the energy dependent escape from the Galaxy E approx. > 10 15 eV produces a steeper spectrum from 10 15 to 10 18 eV. Above this energy SN's in all galaxies fill the meta galaxy with CR's with a flatter slope. Conversely, an external source that attempts to fill the Galaxy from the outside must have a still steeper spectrum ΔGAMMA approx. = -.75 to penetrate the diffusive barrier of our galaxy yet maintain the observed slope. This is unlikely since the energy density at 10 15 eV in the meta galaxy would be between 10 -1 to 10 -2 of CR's in this galaxy or of the order of 10 3 of the energy density of particles and fields in the IGM

  13. Successful "First Light" for VLT High-Resolution Spectrograph

    Science.gov (United States)

    1999-10-01

    pix - 766k] Caption to ESO PR Photo 37c/99 : This false-colour image has been extracted from another UVES echelle spectrum of SN 1987A, similar to the one shown in PR Photo 37b/99 , but with a slit width of 1 arcsec only. The upper part shows the emission lines of nitrogen, sulfur and hydrogen, as recorded in some of the spectral orders. The pixel coordinates (X,Y) in the original frame are indicated; the red colour indicates the highest intensities. Below is a more detailed view of the complex H-alpha emission line, with the corresponding velocities and the position along the spectrograph slit indicated. Several components of this line can be distinguished. The bulk of the emission (here shown in red colour) comes from the ring surrounding the supernova; the elongated shape here is due to the differential velocity exhibited by the near (to us) and far sides of the ring. The two bright spots on either side are emission from two outer rings (not immediately visible in PR Photo 37a/99 ). The extended emission in the velocity direction originates from material inside the ring upon which the fastest moving ejecta from the supernova have impacted (As seen in VLT data obtained previously with the ANTU/ISAAC combination (cf. PR Photo 11/99 ), exciting times now lie ahead for SN 1987A. The ejecta moving at 30,000 km/s (1/10th the speed of light) have now, 12 years after the explosion, reached the ring of material and the predicted "fireworks" are about to be ignited.) Finally, there is a broad emission extending all along the spectrograph slit (here mostly yellow) upon which the ring emission is superimposed. This is not associated with the supernova itself, but is H-alpha emission by diffuse gas in the Large Magellanic Cloud (LMC) in which SN 1987A is located. UVES First Light: QSO HE2217-2818 The power of UVES is demonstrated by this two-hour test exposure of the southern quasar QSO HE2217-2818 with U-magnitude = 16.5 and a redshift of z = 2.4. It was discovered a few years

  14. WAS: the data archive for the WEAVE spectrograph

    NARCIS (Netherlands)

    Guerra, Jose; Molinari, Emilio; Lodi, Marcello; Martin, Adrian; Dalton, Gavin B.; Trager, Scott C.; Jin, Shoko; Abrams, Don Carlos; Bonifacio, Piercarlo; López Aguerri, Jose Alfonso; Vallenari, Antonella; Carrasco Licea, Esperanza E.; Middleton, Kevin F.

    2016-01-01

    The WAS1(WEAVE Archive System) is a software architecture for archiving and delivering the data releases for the WEAVE7 instrument at WHT (William Herschel Telescope). The WEAVE spectrograph will be mounted at the 4.2-m WHT telescope and will provide millions of spectra in a 5-year program, starting

  15. Spectrographic determination of impurities in copper and copper oxide

    International Nuclear Information System (INIS)

    Sabato, S.F.; Lordello, A.R.

    1990-11-01

    An emission spectrographic method for the determination of Al, Bi, Ca, Cd, Cr, Fe, Ge, Mg, Mn, Mo, Ni, Pb, Sb, Si, Sn and Zn in copper and copper oxide is described. Two mixtures (Graphite and ZnO: graphite and GeO sub(2)) were used as buffers. The standard deviation lies around 10%. (author)

  16. The spectrographic orbit of the eclipsing binary HH Carinae

    International Nuclear Information System (INIS)

    Mandrini, C.H.; Mendez, R.H.; Niemela, V.S.; Ferrer, O.E.

    1985-01-01

    We present a radial velocity study of the eclipsing binary system HH Carinae, and determine for the first time its spectrographic orbital elements. Using the results of a previous photometric study by Soderhjelm, we also determine the values of the masses and dimensions of the binary components. (author)

  17. Spectrographic determination of lithium in nuclear grade calcium

    International Nuclear Information System (INIS)

    Artaud, J.; Cittanova, J.

    1957-01-01

    A method is described for the spectrographic determination of lithium in calcium. The samples are converted directly to CaCO 3 . A method of fractional distillation in the arc, using KCl as carrier, makes it possible to detect and measure the Li content to 0,1 ppm. (author) [fr

  18. Supernova Remnants as the Sources of Galactic Cosmic Rays

    NARCIS (Netherlands)

    Vink, J.

    2013-01-01

    The origin of cosmic rays holds still manymysteries hundred years after they were first discovered. Supernova remnants have for long been the most likely sources of Galactic cosmic rays. I discuss here some recent evidence that suggests that supernova remnants can indeed efficiently accelerate

  19. Cosmic radiation doses at flight level altitudes of airliners

    International Nuclear Information System (INIS)

    Viragh, E.; Petr, I.

    1985-01-01

    Changes are discussed in flux density of cosmic radiation particles with time as are the origin of cosmic radiation, the level of cosmic radiation near the Earth's surface, and the determination of cosmic radiation doses in airliners. Doses and dose rates are given measured on different flight routes. In spite of the fact that the flight duration at an altitude of about 10 km makes for about 80% of the total flight time, the overall radiation burden of the crews at 1000 flight hours a year is roughly double that of the rest of the population. (J.C.)

  20. High energy cosmic rays

    CERN Document Server

    Stanev, Todor

    2010-01-01

    Offers an accessible text and reference (a cosmic-ray manual) for graduate students entering the field and high-energy astrophysicists will find this an accessible cosmic-ray manual Easy to read for the general astronomer, the first part describes the standard model of cosmic rays based on our understanding of modern particle physics. Presents the acceleration scenario in some detail in supernovae explosions as well as in the passage of cosmic rays through the Galaxy. Compares experimental data in the atmosphere as well as underground are compared with theoretical models

  1. Cosmology with cosmic shear observations: a review.

    Science.gov (United States)

    Kilbinger, Martin

    2015-07-01

    Cosmic shear is the distortion of images of distant galaxies due to weak gravitational lensing by the large-scale structure in the Universe. Such images are coherently deformed by the tidal field of matter inhomogeneities along the line of sight. By measuring galaxy shape correlations, we can study the properties and evolution of structure on large scales as well as the geometry of the Universe. Thus, cosmic shear has become a powerful probe into the nature of dark matter and the origin of the current accelerated expansion of the Universe. Over the last years, cosmic shear has evolved into a reliable and robust cosmological probe, providing measurements of the expansion history of the Universe and the growth of its structure. We review here the principles of weak gravitational lensing and show how cosmic shear is interpreted in a cosmological context. Then we give an overview of weak-lensing measurements, and present the main observational cosmic-shear results since it was discovered 15 years ago, as well as the implications for cosmology. We then conclude with an outlook on the various future surveys and missions, for which cosmic shear is one of the main science drivers, and discuss promising new weak cosmological lensing techniques for future observations.

  2. Primary cosmic ray flux

    Energy Technology Data Exchange (ETDEWEB)

    Stanev, Todor

    2001-05-01

    We discuss the primary cosmic ray flux from the point of view of particle interactions and production of atmospheric neutrinos. The overall normalization of the cosmic ray flux and its time variations and site dependence are major ingredients of the atmospheric neutrino predictions and the basis for the derivation of the neutrino oscillation parameters.

  3. Cosmic rays on earth

    International Nuclear Information System (INIS)

    Allkofer, O.C.; Grieder, P.K.F.

    1984-01-01

    A data collection is presented that covers cosmic rays on earth. Included are all relevant data on flux and intensity measurements, energy spectra, and related data of all primary and secondary components of the cosmic radiation at all levels in the atmosphere, at sea level and underground. In those cases where no useful experimental data have been available, theoretical predictions were substituted. (GSCH)

  4. Cosmic evolution, life and man

    International Nuclear Information System (INIS)

    Oro, J.

    1995-01-01

    Among the most basic problems confronting science are those regarding the origin of the universe, the origin of life and the origin of man. This general overview starts (1) with a brief introduction addressed primarily to the Cyril Ponnamperuma Memorial. Then, the thesis is presented that the appearance of life and intelligence on our planet can be understood as the result of a number of cosmic and biological evolutionary processes, including (2) the stellar thermonuclear synthesis of the biogenic elements other than hydrogen (C, N, O, P and S), their dispersal into space, and their combination into circumstellar and interstellar molecules. (3) The formation of the Solar System and the Earth-Moon System. (4) The role of comets and carbonaceous chondrites in contributing organic matter to the primitive Earth. (5) The prebiotics synthesis of amino acids, purines, pyrimidines, fatty acids, and other biochemical monomers. (6) The prebiotic condensation reactions leading to the synthesis of oligomers such as oligonucleotides and oligopeptides, with replicative and catalytic activities. (7) The synthesis of amphiphilic lipids, and their self-assembly into liposomes with bi-layered membranes. (8) The formation of protocellular structures. (9) The activation of protocells into a functioning Darwin's ancestral cell. (10) Early evolution of life. (11) The K-T boundary event and the disappearance of dinosaurs. (12) Evolution of hominids leading to Homo sapiens. (13) The rapid development of civilization. (14) The exploration of the Solar System. (15) Life beyond our planetary system. (16) Epilogue. Peace from cosmic evolution? (Abstract only)

  5. Cosmic evolution, life and man

    Energy Technology Data Exchange (ETDEWEB)

    Oro, J [Houston Univ., Houston, TX (United States). Dept. of Biochemical and Biophysical Sciences

    1995-08-01

    Among the most basic problems confronting science are those regarding the origin of the universe, the origin of life and the origin of man. This general overview starts (1) with a brief introduction addressed primarily to the Cyril Ponnamperuma Memorial. Then, the thesis is presented that the appearance of life and intelligence on our planet can be understood as the result of a number of cosmic and biological evolutionary processes, including (2) the stellar thermonuclear synthesis of the biogenic elements other than hydrogen (C, N, O, P and S), their dispersal into space, and their combination into circumstellar and interstellar molecules. (3) The formation of the Solar System and the Earth-Moon System. (4) The role of comets and carbonaceous chondrites in contributing organic matter to the primitive Earth. (5) The prebiotics synthesis of amino acids, purines, pyrimidines, fatty acids, and other biochemical monomers. (6) The prebiotic condensation reactions leading to the synthesis of oligomers such as oligonucleotides and oligopeptides, with replicative and catalytic activities. (7) The synthesis of amphiphilic lipids, and their self-assembly into liposomes with bi-layered membranes. (8) The formation of protocellular structures. (9) The activation of protocells into a functioning Darwin`s ancestral cell. (10) Early evolution of life. (11) The K-T boundary event and the disappearance of dinosaurs. (12) Evolution of hominids leading to Homo sapiens. (13) The rapid development of civilization. (14) The exploration of the Solar System. (15) Life beyond our planetary system. (16) Epilogue. Peace from cosmic evolution? (Abstract only).

  6. Our Cosmic Insignificance

    Science.gov (United States)

    Kahane, Guy

    2014-01-01

    The universe that surrounds us is vast, and we are so very small. When we reflect on the vastness of the universe, our humdrum cosmic location, and the inevitable future demise of humanity, our lives can seem utterly insignificant. Many philosophers assume that such worries about our significance reflect a banal metaethical confusion. They dismiss the very idea of cosmic significance. This, I argue, is a mistake. Worries about cosmic insignificance do not express metaethical worries about objectivity or nihilism, and we can make good sense of the idea of cosmic significance and its absence. It is also possible to explain why the vastness of the universe can make us feel insignificant. This impression does turn out to be mistaken, but not for the reasons typically assumed. In fact, we might be of immense cosmic significance—though we cannot, at this point, tell whether this is the case. PMID:25729095

  7. An echelle spectrograph for middle ultraviolet solar spectroscopy from rockets.

    Science.gov (United States)

    Tousey, R; Purcell, J D; Garrett, D L

    1967-03-01

    An echelle grating spectrograph is ideal for use in a rocket when high resolution is required becaus itoccupies a minimum of space. The instrument described covers the range 4000-2000 A with a resolution of 0.03 A. It was designed to fit into the solar biaxial pointing-control section of an Aerobee-150 rocket. The characteristics of the spectrograph are illustrated with laboratory spectra of iron and carbon are sources and with solar spectra obtained during rocket flights in 1961 and 1964. Problems encountered in analyzing the spectra are discussed. The most difficult design problem was the elimination of stray light when used with the sun. Of the several methods investigated, the most effective was a predispersing system in the form of a zero-dispersion double monochromator. This was made compact by folding the beam four times.

  8. Ultraviolet spectrographs for thermospheric and ionospheric remote sensing

    International Nuclear Information System (INIS)

    Dymond, K.F.; McCoy, R.P.

    1993-01-01

    The Naval Research Laboratory (NRL) has been developing far- and extreme-ultraviolet spectrographs for remote sensing the Earth's upper atmosphere and ionosphere. The first of these sensors, called the Special Sensor Ultraviolet Limb Imager (SSULI), will be flying on the Air Force's Defense Meteorological Satellite Program (DMSP) block 5D3 satellites as an operational sensor in the 1997-2010 time frame. A second sensor, called the High-resolution ionospheric and Thermospheric Spectrograph (HITS), will fly in late 1995 on the Air Force Space Test Program's Advanced Research and Global Observation Satellite (ARGOS, also known as P91-1) as part of NRL's High Resolution Airglow and Auroral Spectroscopy (HIRAAS) experiment. Both of these instruments are compact and do not draw much power and would be good candidates for small satellite applications. The instruments and their capabilities are discussed. Possible uses of these instruments in small satellite applications are also presented

  9. Spectrographic determination of trace impurities in reactor grade aluminium

    International Nuclear Information System (INIS)

    Chandola, L.C.; Machado, I.J.

    1975-01-01

    A spectrographic method enabling the determination of 21 trace impurities in aluminium oxide is described. The technique involves mixing the sample with graphite buffer in the ratio 1:1, loading it in a graphite electrode and arcing it for 30 sec. in a dc arc to 10 A current against a pointed graphite cathode. The spectra are photographed on Ilford N.30 emulsion employing a large quartz spectrograph. The aluminium line at 2669.2 A 0 serves as the internal standard. The impurities determined are Ag, B, Bi, Cd, Co, Cr, Cu, Fe, Ga, In, Mg, Mo, Ni, Pb, Sb, Si, Sn, Ti, V and Zn. The sensitivity varies from 5 to 100 ppm and the precision from +- 5 to +- 22% for different elements. A method for converting aluminium metal to aluminium oxide is described. It is found that boron is not lost during this conversion. (author)

  10. Atmospheric ionization and cosmic rays: studies and measurements before 1912

    OpenAIRE

    De Angelis, Alessandro

    2012-01-01

    The discovery of cosmic rays, a milestone in science, was based on the work by scientists in Europe and the New World and took place during a period characterised by nationalism and lack of communication. Many scientists that took part in this research a century ago were intrigued by the penetrating radiation and tried to understand the origin of it. Several important contributions to the discovery of the origin of cosmic rays have been forgotten; historical, political and personal facts migh...

  11. Proton polarimetry using an Enge split-pole spectrograph

    Energy Technology Data Exchange (ETDEWEB)

    Moss, J M; Brown, D R; Cornelius, W D [Texas Agricultural and Mechanical Univ., College Station (USA). Cyclotron Inst.

    1976-05-15

    A high-efficiency (4 x 10/sup -5/ at A=0.4) high resolution (150 keV) polarimeter used in conjunction with an Enge split-pole spectrograph is described. This device permits for the first time polarization transfer studies in elastic scattering. Spectra are shown for /sup 11/B(p(pol),p(pol)')/sup 11/B (2.14 MeV)at Esub(p)=31 MeV.

  12. A CCD fitted to the UV Prime spectrograph: Performance

    International Nuclear Information System (INIS)

    Boulade, O.

    1986-10-01

    A CCD camera was fitted to the 3.6 m French-Canadian telescope in Hawai. Performance of the system and observations of elliptic galaxies (stellar content and galactic evolution in a cluster) and quasars (absorption lines in spectra) are reported. In spite of its resolution being only average, the extremely rapid optics of the UV spectrograph gives good signal to noise ratios enabling redshifts and velocity scatter to be calculated with an accuracy better than 30 km/sec [fr

  13. Solar glint suppression in compact planetary ultraviolet spectrographs

    Science.gov (United States)

    Davis, Michael W.; Cook, Jason C.; Grava, Cesare; Greathouse, Thomas K.; Gladstone, G. Randall; Retherford, Kurt D.

    2015-08-01

    Solar glint suppression is an important consideration in the design of compact photon-counting ultraviolet spectrographs. Southwest Research Institute developed the Lyman Alpha Mapping Project for the Lunar Reconnaissance Orbiter (launch in 2009), and the Ultraviolet Spectrograph on Juno (Juno-UVS, launch in 2011). Both of these compact spectrographs revealed minor solar glints in flight that did not appear in pre-launch analyses. These glints only appeared when their respective spacecraft were operating outside primary science mission parameters. Post-facto scattered light analysis verifies the geometries at which these glints occurred and why they were not caught during ground testing or nominal mission operations. The limitations of standard baffle design at near-grazing angles are discussed, as well as the importance of including surface scatter properties in standard stray light analyses when determining solar keep-out efficiency. In particular, the scattered light analysis of these two instruments shows that standard "one bounce" assumptions in baffle design are not always enough to prevent scattered sunlight from reaching the instrument focal plane. Future builds, such as JUICE-UVS, will implement improved scattered and stray light modeling early in the design phase to enhance capabilities in extended mission science phases, as well as optimize solar keep out volume.

  14. SPRAT: Spectrograph for the Rapid Acquisition of Transients

    Science.gov (United States)

    Piascik, A. S.; Steele, Iain A.; Bates, Stuart D.; Mottram, Christopher J.; Smith, R. J.; Barnsley, R. M.; Bolton, B.

    2014-07-01

    We describe the development of a low cost, low resolution (R ~ 350), high throughput, long slit spectrograph covering visible (4000-8000) wavelengths. The spectrograph has been developed for fully robotic operation with the Liverpool Telescope (La Palma). The primary aim is to provide rapid spectral classification of faint (V ˜ 20) transient objects detected by projects such as Gaia, iPTF (intermediate Palomar Transient Factory), LOFAR, and a variety of high energy satellites. The design employs a volume phase holographic (VPH) transmission grating as the dispersive element combined with a prism pair (grism) in a linear optical path. One of two peak spectral sensitivities are selectable by rotating the grism. The VPH and prism combination and entrance slit are deployable, and when removed from the beam allow the collimator/camera pair to re-image the target field onto the detector. This mode of operation provides automatic acquisition of the target onto the slit prior to spectrographic observation through World Coordinate System fitting. The selection and characterisation of optical components to maximise photon throughput is described together with performance predictions.

  15. Light scattering by cosmic particles

    NARCIS (Netherlands)

    Hovenier, J.W.; Min, M.

    2008-01-01

    We define cosmic particles as particles outside the Earth. Two types of cosmic particles can be distinguished, namely liquid and solid particles. The solid particles are often called grains or cosmic dust particles. Cosmic particles occur in a great variety of astronomical objects and environments.

  16. 11. European cosmic ray symposium

    International Nuclear Information System (INIS)

    1989-03-01

    The biannual Symposium includes all aspects of cosmic ray research. The scientific programme was organized under three main headings: Cosmic rays in the heliosphere, Cosmic rays in the interstellar and extragalactic space, Properties of high-energy interactions as studied by cosmic rays. Seven invited talks were indexed seprately for the INIS database. (R.P.)

  17. The Astrobiological Case for Our Cosmic Ancestry

    Science.gov (United States)

    Wickramasinghe, Chandra

    With steadily mounting evidence that points to a cosmic origin of terrestrial life, a cultural barrier prevails against admitting that such a connection exists. Astronomy continues to reveal the presence of organic molecules and organic dust on a huge cosmic scale, amounting to a third of interstellar carbon tied up in this form. Just as the overwhelming bulk of organics on Earth stored over geological timescales are derived from the degradation of living cells, so it seems most likely that interstellar organics in large measure also derive from biology. As we enter a new decade -- the year 2010 -- a clear pronouncement of our likely alien ancestry and of the existence of extraterrestrial life on a cosmic scale would seem to be overdue.

  18. The propagation of galactic cosmic rays

    International Nuclear Information System (INIS)

    Hall, A.N.

    1981-01-01

    Large scale (approximately 15 pc) turbulence in the interstellar medium (ISM) causes the firehose and mirror instabilities to occur. These produce small scale (approximately 10 -7 pc) magnetic irregularities, which scatter cosmic rays. We use pulsar scintillation data, and a model of the origin of these scintillations, to construct a slab model of the turbulent ISM. Then we find the amplitudes and wavelengths of the magnetic irregularities that arise, and we calculate the coefficients for the diffusion of cosmic rays along the interstellar magnetic fields. We incorporate this diffusion into our model of the turbulent ISM, and show that it can account naturally for both the lifetime of low energy cosmic rays, and the variation of their mean pathlength with energy. Our model has no galactic halo, and contains no scattering by Alfven waves. (author)

  19. Fluctuations in the cosmic microwave background

    International Nuclear Information System (INIS)

    Banday, A.J.; Wolfendale, A.W.

    1990-01-01

    In view of the importance to contemporary cosmology, and to our understanding of the Universe, of the precise nature of the Cosmic Microwave Background (CMB) spectrum, we consider the effects on this spectrum of contamination by other radiation fields of both galactic and extragalactic origin. Particular attention is given to the significance of measurements of the fluctuations in the 'background' radiation detected at 10.46 GHz and we conclude that these fluctuations are of the same magnitude as those expected from galactic cosmic-ray effects. A more detailed study of the cosmic-ray induced fluctuations and measurements at higher frequencies will be needed before genuine CMB fluctuations can be claimed. (author)

  20. SPECTROGRAPHIC DETERMINATION OF BERYLLIUM IN OILFIELD WATERS USING A PLASMA ARC

    Energy Technology Data Exchange (ETDEWEB)

    Collins, A. G.; Pearson, C. A.

    1963-10-15

    Geochemical studies of the distribution of the trace, minor, and major constituents of oilfield waters aid in the exploration for petroleum and other minerals, determination of the origin and distribution of oilfield waters and petroleum, and location of casing leaks and of water pollution sources. The determination of the beryllium and related data should be useful in these studies. An emission spectrographic method utilizing a plasma arc assembly for determining beryllium in oilfield waters, with a sensitivity permitting detection of less than 1 ppb, was developed. Beryllium was extracted from synthetic and natural oilfield waters with chloroform and acetylacetone. The extracts were aspirated directly into the plasma arc, and the beryllium emission intensity was recorded on photographic plates. (auth)

  1. Digital TV-echelle spectrograph for simultaneous multielemental analysis using microcomputer control

    International Nuclear Information System (INIS)

    Davidson, J.B.; Case, A.L.

    1980-12-01

    A digital TV-echelle spectrograph with microcomputer control was developed for simultaneous multielemental analysis. The optical system is a commercially available unit originally equipped for film and photomultiplier (single element) readout. The film port was adapted for the intensifier camera. The camera output is digitized and stored in a microcomputer-controlled, 512 x 512 x 12 bit memory and image processor. Multiple spectra over the range of 200 to 800 nm are recorded in a single exposure. Spectra lasting from nanoseconds to seconds are digitized and stored in 0.033 s and displayed on a TV monitor. An inexpensive microcomputer controls the exposure, reads and displays the intensity of predetermined spectral lines, and calculates wavelengths of unknown lines. The digital addresses of unknown lines are determined by superimposing a cursor on the TV display. The microcomputer also writes into memory wavelength fiducial marks for alignment of the TV camera

  2. Cosmic gamma bursts

    International Nuclear Information System (INIS)

    Ehstulin, I.V.

    1980-01-01

    A brief consideration is being given to the history of cosmic gamma burst discovery and modern knowledge of their properties. The time dependence of gamma bursts is described and their possible sources are discussed

  3. Cosmic microwave background radiation

    International Nuclear Information System (INIS)

    Wilson, R.W.

    1979-01-01

    The 20-ft horn-reflector antenna at Bell Laboratories is discussed in detail with emphasis on the 7.35 cm radiometer. The circumstances leading to the detection of the cosmic microwave background radiation are explored

  4. Cosmic ray acceleration mechanisms

    International Nuclear Information System (INIS)

    Cesarsky, C.J.

    1982-09-01

    We present a brief summary of some of the most popular theories of cosmic ray acceleration: Fermi acceleration, its application to acceleration by shocks in a scattering medium, and impulsive acceleration by relativistic shocks

  5. Xenia: A Probe of Cosmic Chemical Evolution

    Science.gov (United States)

    Kouveliotou, Chryssa; Piro, L.; Xenia Collaboration

    2008-03-01

    Xenia is a concept study for a medium-size astrophysical cosmology mission addressing the Cosmic Origins key objective of NASA's Science Plan. The fundamental goal of this objective is to understand the formation and evolution of structures on various scales from the early Universe to the present time (stars, galaxies and the cosmic web). Xenia will use X-and γ-ray monitoring and wide field X-ray imaging and high-resolution spectroscopy to collect essential information from three major tracers of these cosmic structures: the Warm Hot Intergalactic Medium (WHIM), Galaxy Clusters and Gamma Ray Bursts (GRBs). Our goal is to trace the chemo-dynamical history of the ubiquitous warm hot diffuse baryon component in the Universe residing in cosmic filaments and clusters of galaxies up to its formation epoch (at z =0-2) and to map star formation and galaxy metal enrichment into the re-ionization era beyond z 6. The concept of Xenia (Greek for "hospitality") evolved in parallel with the Explorer of Diffuse Emission and GRB Explosions (EDGE), a mission proposed by a multinational collaboration to the ESA Cosmic Vision 2015. Xenia incorporates the European and Japanese collaborators into a U.S. led mission that builds on the scientific objectives and technological readiness of EDGE.

  6. Xenia: A Probe of Cosmic Chemical Evolution

    Science.gov (United States)

    Kouveliotou, Chryssa; Piro, L.

    2008-01-01

    Xenia is a concept study for a medium-size astrophysical cosmology mission addressing the Cosmic Origins key objective of NASA's Science Plan. The fundamental goal of this objective is to understand the formation and evolution of structures on various scales from the early Universe to the present time (stars, galaxies and the cosmic web). Xenia will use X-and y-ray monitoring and wide field X-ray imaging and high-resolution spectroscopy to collect essential information from three major tracers of these cosmic structures: the Warm Hot Intergalactic Medium (WHIM), Galaxy Clusters and Gamma Ray Bursts (GRBs). Our goal is to trace the chemo-dynamical history of the ubiquitous warm hot diffuse baryon component in the Universe residing in cosmic filaments and clusters of galaxies up to its formation epoch (at z =0-2) and to map star formation and galaxy metal enrichment into the re-ionization era beyond z 6. The concept of Xenia (Greek for "hospitality") evolved in parallel with the Explorer of Diffuse Emission and GRB Explosions (EDGE), a mission proposed by a multinational collaboration to the ESA Cosmic Vision 2015. Xenia incorporates the European and Japanese collaborators into a U.S. led mission that builds on the scientific objectives and technological readiness of EDGE.

  7. Cosmic rays and tests of fundamental principles

    Science.gov (United States)

    Gonzalez-Mestres, Luis

    2011-03-01

    It is now widely acknowledged that cosmic rays experiments can test possible new physics directly generated at the Planck scale or at some other fundamental scale. By studying particle properties at energies far beyond the reach of any man-made accelerator, they can yield unique checks of basic principles. A well-known example is provided by possible tests of special relativity at the highest cosmic-ray energies. But other essential ingredients of standard theories can in principle be tested: quantum mechanics, uncertainty principle, energy and momentum conservation, effective space-time dimensions, hamiltonian and lagrangian formalisms, postulates of cosmology, vacuum dynamics and particle propagation, quark and gluon confinement, elementariness of particles…Standard particle physics or string-like patterns may have a composite origin able to manifest itself through specific cosmic-ray signatures. Ultra-high energy cosmic rays, but also cosmic rays at lower energies, are probes of both "conventional" and new Physics. Status, prospects, new ideas, and open questions in the field are discussed.

  8. Cosmic rays and tests of fundamental principles

    International Nuclear Information System (INIS)

    Gonzalez-Mestres, Luis

    2011-01-01

    It is now widely acknowledged that cosmic rays experiments can test possible new physics directly generated at the Planck scale or at some other fundamental scale. By studying particle properties at energies far beyond the reach of any man-made accelerator, they can yield unique checks of basic principles. A well-known example is provided by possible tests of special relativity at the highest cosmic-ray energies. But other essential ingredients of standard theories can in principle be tested: quantum mechanics, uncertainty principle, energy and momentum conservation, effective space-time dimensions, hamiltonian and lagrangian formalisms, postulates of cosmology, vacuum dynamics and particle propagation, quark and gluon confinement, elementariness of particles... Standard particle physics or string-like patterns may have a composite origin able to manifest itself through specific cosmic-ray signatures. Ultra-high energy cosmic rays, but also cosmic rays at lower energies, are probes of both 'conventional' and new Physics. Status, prospects, new ideas, and open questions in the field are discussed.

  9. A COSMIC VARIANCE COOKBOOK

    International Nuclear Information System (INIS)

    Moster, Benjamin P.; Rix, Hans-Walter; Somerville, Rachel S.; Newman, Jeffrey A.

    2011-01-01

    Deep pencil beam surveys ( 2 ) are of fundamental importance for studying the high-redshift universe. However, inferences about galaxy population properties (e.g., the abundance of objects) are in practice limited by 'cosmic variance'. This is the uncertainty in observational estimates of the number density of galaxies arising from the underlying large-scale density fluctuations. This source of uncertainty can be significant, especially for surveys which cover only small areas and for massive high-redshift galaxies. Cosmic variance for a given galaxy population can be determined using predictions from cold dark matter theory and the galaxy bias. In this paper, we provide tools for experiment design and interpretation. For a given survey geometry, we present the cosmic variance of dark matter as a function of mean redshift z-bar and redshift bin size Δz. Using a halo occupation model to predict galaxy clustering, we derive the galaxy bias as a function of mean redshift for galaxy samples of a given stellar mass range. In the linear regime, the cosmic variance of these galaxy samples is the product of the galaxy bias and the dark matter cosmic variance. We present a simple recipe using a fitting function to compute cosmic variance as a function of the angular dimensions of the field, z-bar , Δz, and stellar mass m * . We also provide tabulated values and a software tool. The accuracy of the resulting cosmic variance estimates (δσ v /σ v ) is shown to be better than 20%. We find that for GOODS at z-bar =2 and with Δz = 0.5, the relative cosmic variance of galaxies with m * >10 11 M sun is ∼38%, while it is ∼27% for GEMS and ∼12% for COSMOS. For galaxies of m * ∼ 10 10 M sun , the relative cosmic variance is ∼19% for GOODS, ∼13% for GEMS, and ∼6% for COSMOS. This implies that cosmic variance is a significant source of uncertainty at z-bar =2 for small fields and massive galaxies, while for larger fields and intermediate mass galaxies, cosmic

  10. Progress in high-energy cosmic ray physics

    Science.gov (United States)

    Mollerach, S.; Roulet, E.

    2018-01-01

    We review some of the recent progress in our knowledge about high-energy cosmic rays, with an emphasis on the interpretation of the different observational results. We discuss the effects that are relevant to shape the cosmic ray spectrum and the explanations proposed to account for its features and for the observed changes in composition. The physics of air-showers is summarized and we also present the results obtained on the proton-air cross section and on the muon content of the showers. We discuss the cosmic ray propagation through magnetic fields, the effects of diffusion and of magnetic lensing, the cosmic ray interactions with background radiation fields and the production of secondary neutrinos and photons. We also consider the cosmic ray anisotropies, both at large and small angular scales, presenting the results obtained from the TeV up to the highest energies and discuss the models proposed to explain their origin.

  11. Phono-spectrographic analysis of heart murmur in children

    Directory of Open Access Journals (Sweden)

    Angerla Anna

    2007-06-01

    Full Text Available Abstract Background More than 90% of heart murmurs in children are innocent. Frequently the skills of the first examiner are not adequate to differentiate between innocent and pathological murmurs. Our goal was to evaluate the value of a simple and low-cost phonocardiographic recording and analysis system in determining the characteristic features of heart murmurs in children and in distinguishing innocent systolic murmurs from pathological. Methods The system consisting of an electronic stethoscope and a multimedia laptop computer was used for the recording, monitoring and analysis of auscultation findings. The recorded sounds were examined graphically and numerically using combined phono-spectrograms. The data consisted of heart sound recordings from 807 pediatric patients, including 88 normal cases without any murmur, 447 innocent murmurs and 272 pathological murmurs. The phono-spectrographic features of heart murmurs were examined visually and numerically. From this database, 50 innocent vibratory murmurs, 25 innocent ejection murmurs and 50 easily confusable, mildly pathological systolic murmurs were selected to test whether quantitative phono-spectrographic analysis could be used as an accurate screening tool for systolic heart murmurs in children. Results The phono-spectrograms of the most common innocent and pathological murmurs were presented as examples of the whole data set. Typically, innocent murmurs had lower frequencies (below 200 Hz and a frequency spectrum with a more harmonic structure than pathological cases. Quantitative analysis revealed no significant differences in the duration of S1 and S2 or loudness of systolic murmurs between the pathological and physiological systolic murmurs. However, the pathological murmurs included both lower and higher frequencies than the physiological ones (p Conclusion Phono-spectrographic analysis improves the accuracy of primary heart murmur evaluation and educates inexperienced listener

  12. Department of Cosmic Ray Physics; Overview

    International Nuclear Information System (INIS)

    Szabelski, J.

    2004-01-01

    Full text: Cosmic Rays are energetic particles from outside the Solar System. The energy spectrum (power law energy dependence) suggests a non-thermal origin of these particles. Most of the studies of Cosmic Rays address fundamental problems such as: - the nature of the physical and astrophysical processes responsible for the high energies of particles (up to about 10 20 eV/particle), - estimation of the astrophysical conditions at the acceleration sites and/or a search for sources of Cosmic Rays, - properties of high energy particle interactions at very high energies (nuclear interactions at energies exceeding energies available in the laboratories). Some Cosmic Ray studies might have practical (commercial) implications, e.g. - ''cosmic weather'' forecast - predictions of geomagnetic disturbances related to Solar activity changes (due to large Solar Flares / events of Coronal Mass Ejections); these are important for large electricity networks, gas pipes, radio-wave connections, space missions and satellite experiments. The Department of Cosmic Ray Physics in Lodz is involved in basic research in the high energy Cosmic Ray field. Energetic Cosmic Ray particles produce cascades of particles in the atmosphere, called Extensive Air Showers (EAS). Registering EAS and their properties is the main theme of experimental studies of very high energy Cosmic Rays. In the Lodz Department we run an Extensive Air Shower array where EAS are registered. We concentrate our experimental research on the explanation of particle detection delayed by hundreds of microseconds with respect to the main EAS signals. In the underground (I5 meters) laboratory we continuously register muon (5 GeV energy threshold) flux with the multidirectional telescope. We have observed several disturbances (Forbush Decreases) in muon counting rates. The interpretation of these events for ''cosmic weather'' and for Cosmic Ray transport models in the interplanetary plasma are on going in collaboration with

  13. Sensitivity Calibration of Far-Ultraviolet Imaging Spectrograph

    Directory of Open Access Journals (Sweden)

    I. -J. Kim

    2004-12-01

    Full Text Available We describe the in-flight sensitivity calibration of the Far ultraviolet Imaging Spectrograph (FIMS, also known as SPEAR onboard the first Korean science satellite, STSAT-1, which was launched in September 2003. The sensitivity calibration is based on a comparison of the FIMS observations of the hot white dwarf G191B2B, and two O-type stars Alpha-Cam, HD93521 with the HUT (Hopkins Ultraviolet Telescope observations. The FIMS observations for the calibration targets have been conducted from November 2003 through May 2004. The effective areas calculated from the targets are compared with each other.

  14. Spectrographic determination of niobium in uranium - niobium alloys

    International Nuclear Information System (INIS)

    Charbel, M.Y.; Lordello, A.R.

    1984-01-01

    A method for the spectrographic determination of niobium in uranium-niobium alloys in the concentration range 1-10% has been developed. The metallic sample is converted to oxide by calcination in a muffle furnace at 800 0 C for two hours. The standards are prepared synthetically by dry-mixing. One part of the sample or standard is added to nineteen parts of graphite powder and the mixture is excited in a DC arc. Hafnium has been used as internal standard. The precision of the method is + - 4.8%. (Author) [pt

  15. Quantitative spectrographic determination of traces of manganese in ferric oxide

    International Nuclear Information System (INIS)

    Capdevila, C.; Roca, M.

    1968-01-01

    In order to enhance the sensitivity, different electrode types and sweeping substances have been studied. Graphite anodes, with 5 x 2,5, 4 x 4,5, 4 x 8 and 7 x 10 mm crater, as well as CuF 2 , AgCl, ZnO and graphite powder as sweeping materials, have been tested. A JACO-Ebert grating spectrograph and 10 amp. d.c. arc have been employed, choosing the proper exposure times from moving-plate studies. Using 4 x 4,5 mm electrodes and 75% AgCl a detection limit of 0,2 ppm is attainable. (Author) 7 refs

  16. Spectrographic determination of impurities in ammonium hydrogen fluoride samples

    International Nuclear Information System (INIS)

    Roca, M.; Capdevila, C.; Alduan, F.A.

    1976-01-01

    The quantitative spectrographic trace determination of Al, B, Cr, Cu, Fe, Mn, Mo, Ni, Pb and Si in ammonium hydrogen fluoride samples is considered. 10 A dc arc excitation and graphite electrodes with crate either 4.5 mm or 8 mm deep are employed. A comparison of various matrices such as graphite, gallium oxide, germanium oxide, magnesium oxide and zinc oxide, in the ratios 1:1 and 1:3, as well as a mixture 50% graphite - 50% zinc oxide in the ratio 1:1 is included. Zinc oxide in the ratio 1:1 and 4x8 mm craters show the best over-all results. (author)

  17. Study of airborne particles by emission spectrographic method

    Energy Technology Data Exchange (ETDEWEB)

    Chao, C N; Lee, S L; Tsai, H T; Wu, S C

    1975-03-01

    A rapid spectrographic method was developed to analyze cadmium, lead, nickel, zinc, tin, titanium, and vanadium collected in glass fiber air filters. A direct excitation method is used for volatile elements, while graphite powder is added for determining involatile elements, such as Ti and V in a dc arc source. Limits of detection for analyzed elements are between 0.01-0.1 micrograms. This simple and sensitive method was used to analyze samples from 15 air sampling stations in different areas of Taiwan.

  18. Spectrographic determination of impurities in enriched uranium solutions

    International Nuclear Information System (INIS)

    Capdevila, C.; Roca, M.

    1980-01-01

    A spectrographic procedure for the determination of trace amounts of Al, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, K, L i , Hg, Mn, Mo, Na, Nb, Ni, P, Pb, Ru, Sb, Sn, Sr, Ti, V, Zn, and Zr in enriched uranyl nitrate solutions from the reprocessing of spent nuclear fuels is described. After removal of uranium by either TBP or TNOA solvent extraction, the aqueous phase Is analysed by the graphite spark technique. TBP is adequate for all impurities, excepting boron and phosphorus; both of these elements can sat is factory be determined by using TNOA after the addition of mannitol to avoid boron losses. (Author) 4 refs

  19. Spectrographic study of neodymium complexing with ATP and ADP

    International Nuclear Information System (INIS)

    Svetlova, I.E.; Dobrynina, N.A.; Martynenko, L.N.

    1989-01-01

    By spectrographic method neodymium complexing with ATP and ADP in aqueous solutions at different pH values has been studied. The composition of the complexes was determined by the method of isomolar series. On the basis of analysis of absorption spectra it has been ascertained that at equimolar ratio of Nd 3+ and ATP absorption band of L278A corresponds to monocomplex, and the band of 4290 A - to biscomplex. For the complexes with ADP the absorption band of 4288 A is referred to bicomplexes. The character of ATP and ADP coordination by Nd 3+ ion is considered. Stability constants of the complexes are calculated

  20. A UV prime focus spectrograph for the CFHT

    International Nuclear Information System (INIS)

    Boulade, O.; Vigroux, L.

    1986-03-01

    The UV prime spectrograph at the Canada-France-Hawaii Telescope is the first instrument to be designed with an aspherized diffraction grating. This technique leads to all reflective Schmidt designs with a very small amount of optical surface on fast aperture ratio. A thin backside illuminated RCA CCD is now used as the detector. Since the detector is at the focus of an f/1 mounting, within the optical path, a minicryostat (5 cm x 5 cm x 3 cm) was designed to minimize the central obscuration. This paper describes this new instrument and its performances

  1. The spectrographic analysis of inorganic impurities in heavy water

    International Nuclear Information System (INIS)

    Artaud, J.; Normand, J.; Vie, R.

    1961-01-01

    Inorganic impurities in heavy water are determined by two spectrographic methods. First is described the copper-spark method which is sensitive and directly applicable, and is particular useful because of the absence of a support. Secondly the graphite impregnation method is given; this is used when the first method is not applicable (determination of copper) and for the alkali metals. For the usual elements, the sensitivity of the copper spark method is of the order of 0,1 μg/ml whereas for the graphite impregnation method the sensitivity is only 0,3 μg/ml. (author) [fr

  2. Exoplanets search and characterization with the SOPHIE spectrograph at OHP

    Directory of Open Access Journals (Sweden)

    Hébrard G.

    2011-02-01

    Full Text Available Several programs of exoplanets search and characterization have been started with SOPHIE at the 1.93-m telescope of Haute-Provence Observatory, France. SOPHIE is an environmentally stabilized echelle spectrograph dedicated to high-precision radial velocity measurements. The objectives of these programs include systematic searches for exoplanets around different types of stars, characterizations of planet-host stars, studies of transiting planets through RossiterMcLaughlin effect, follow-up observations of photometric surveys. The instrument SOPHIE and a review of its latest results are presented here.

  3. Spectrographic mask for digital registration of bright source spectra

    Directory of Open Access Journals (Sweden)

    Ademir Xavier

    2017-08-01

    Full Text Available In this work we present schematic diagrams for the construction of a spectrographic mask attachable to a camera objective in order to capture spectra using simple CD or DVD gratings. The mask is made of two parts: an adapter ring and elbow-shaped blockage for suitable registration of spectra in the lab and outdoors. By using a free software, we analyze and discuss the calibration of the wavelength scale of the solar spectrum, which allows us to identify many chemical elements in it. In the conclusion, we further discuss some interesting projects to be carried out by students using the idea.

  4. Rapid spectrographic method for determining microcomponents in solutions

    International Nuclear Information System (INIS)

    Karpenko, L.I.; Fadeeva, L.A.; Gordeeva, A.N.; Ermakova, N.V.

    1984-01-01

    Rapid spectrographic method foe determining microcomponents (Cd, V, Mo, Ni, rare earths and other elements) in industrial and natural solutions has been developed. The analyses were conducted in argon medium and in the air. Calibration charts for determining individual rare earths in solutions are presented. The accuracy of analysis (Sr) was detection limit was 10 -3 -10 -4 mg/ml, that for rare earths - 1.10 -2 mg/ml. The developed method enables to rapidly analyze solutions (sewages and industrialllwaters, wine products) for 20 elements including 6 rare earths, using strandard equipment

  5. Most Efficient Spectrograph to Shoot the Southern Skies

    Science.gov (United States)

    2009-05-01

    instrument to use for a detailed study. Thanks to X-shooter, astronomers won't have to go through this first observing step. This is particularly relevant for gamma-ray bursts, which fade away very quickly and where being fast is the key to understanding the nature of these elusive cosmic sources. "I am very confident that X-shooter will discover the most distant gamma-ray bursts in the Universe, or in other words, the first objects that formed in the young Universe," says François Hammer, who leads the French efforts in X-shooter. X-shooter was built by a consortium of 11 institutes in Denmark, France, Italy and the Netherlands, together with ESO. In total 68 person-years of work by engineers, technicians and astronomers and a global budget of six million Euros were required. The development time was remarkably fast for a project of this complexity, which was completed in just over five years, starting from the kick-off meeting held in December 2003. "The success of X-shooter and its relatively short completion time are a tribute to the quality and dedication of the many people involved in the project," says Alan Moorwood, ESO Director of Programmes. The instrument was installed at the telescope at the end of 2008 and the first observations in its full configuration were made on 14 March 2009, demonstrating that the instrument works efficiently over the full spectral range with unprecedented resolution and quality. X-shooter has already proved its full capability by obtaining the complete spectra of low metallicity stars, of X-ray binaries, of distant quasars and galaxies, of the nebulae associated with Eta Carinae and the supernova 1987A, as well as with the observation of a distant gamma-ray burst that coincidently exploded at the time of the commissioning run. X-shooter will be offered to the astronomical community from 1 October 2009. The instrument is clearly answering a need in the scientific community as about 150 proposals were received for the first runs of X

  6. Cosmic rays in space

    International Nuclear Information System (INIS)

    Fujitaka, Kazunobu

    2005-01-01

    Cosmos is a mysterious space by which many researchers are fascinated for many years. But, going into space means that we will receive extra exposure due to existence of cosmic rays. Cosmic rays are mainly composed of highly energetic protons. It was born in the last stage of stellar life. Understanding of cosmos will certainly bring right understanding of radiation energy, or energy itself. As no one could see the very early stage of cosmic rays, there is only a speculation. But it is better to speculate something based on certain side evidences, than to give up the whole. Such attitude shall be welcomed in the space researches. Anyway, cosmic rays were born in the last explosion of a star, which is called as Super Nova. After cosmic rays are emitted from the Super Nova, it will reach to the human surroundings. To indicate its intensity, special unit of ''dose rate'' is used. When a man climbs a mountain, cosmic ray intensity surely increases. It doubles as he goes up every 1500m elevation. It was ascertained by our own measurements. Then what happens when the goes up more? At aviation altitude, where airplanes fly, the dose rate will be increased up to 100times the high mountain cases. And what is expected when he goes up further more, up to space orbit altitude? In this case, the dose rate increases up to 10times the airplane cases. Geomagnetism affects the dose rate very much. As primary cosmic ray particles are charged particles, they cannot do well with existence of the magnetic field. In effect, cosmic rays can penetrate into the polar atmosphere along geomagnetic lines of forces which stand almost vertical, but penetration of low energy cosmic rays will be banned when they intend to penetrate crossing the geomagnetic lines of forces in equatorial region. Therefore, exposure due to cosmic rays will become large in polar region, while it remains small in equatorial region. In effect, airplanes which fly over the equator. Only, we have to know that the cosmos

  7. Observational probes of cosmic acceleration

    International Nuclear Information System (INIS)

    Weinberg, David H.; Mortonson, Michael J.; Eisenstein, Daniel J.; Hirata, Christopher; Riess, Adam G.; Rozo, Eduardo

    2013-01-01

    The accelerating expansion of the universe is the most surprising cosmological discovery in many decades, implying that the universe is dominated by some form of “dark energy” with exotic physical properties, or that Einstein’s theory of gravity breaks down on cosmological scales. The profound implications of cosmic acceleration have inspired ambitious efforts to understand its origin, with experiments that aim to measure the history of expansion and growth of structure with percent-level precision or higher. We review in detail the four most well established methods for making such measurements: Type Ia supernovae, baryon acoustic oscillations (BAO), weak gravitational lensing, and the abundance of galaxy clusters. We pay particular attention to the systematic uncertainties in these techniques and to strategies for controlling them at the level needed to exploit “Stage IV” dark energy facilities such as BigBOSS, LSST, Euclid, and WFIRST. We briefly review a number of other approaches including redshift-space distortions, the Alcock–Paczynski effect, and direct measurements of the Hubble constant H 0 . We present extensive forecasts for constraints on the dark energy equation of state and parameterized deviations from General Relativity, achievable with Stage III and Stage IV experimental programs that incorporate supernovae, BAO, weak lensing, and cosmic microwave background data. We also show the level of precision required for clusters or other methods to provide constraints competitive with those of these fiducial programs. We emphasize the value of a balanced program that employs several of the most powerful methods in combination, both to cross-check systematic uncertainties and to take advantage of complementary information. Surveys to probe cosmic acceleration produce data sets that support a wide range of scientific investigations, and they continue the longstanding astronomical tradition of mapping the universe in ever greater detail over ever

  8. Observational probes of cosmic acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Weinberg, David H., E-mail: dhw@astronomy.ohio-state.edu [Department of Astronomy, Ohio State University, Columbus, OH (United States); Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH (United States); Mortonson, Michael J. [Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH (United States); Eisenstein, Daniel J. [Steward Observatory, University of Arizona, Tucson, AZ (United States); Harvard College Observatory, Cambridge, MA (United States); Hirata, Christopher [California Institute of Technology, Pasadena, CA (United States); Riess, Adam G. [Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD (United States); Rozo, Eduardo [Kavli Institute for Cosmological Physics, University of Chicago, Chicago, IL (United States)

    2013-09-10

    The accelerating expansion of the universe is the most surprising cosmological discovery in many decades, implying that the universe is dominated by some form of “dark energy” with exotic physical properties, or that Einstein’s theory of gravity breaks down on cosmological scales. The profound implications of cosmic acceleration have inspired ambitious efforts to understand its origin, with experiments that aim to measure the history of expansion and growth of structure with percent-level precision or higher. We review in detail the four most well established methods for making such measurements: Type Ia supernovae, baryon acoustic oscillations (BAO), weak gravitational lensing, and the abundance of galaxy clusters. We pay particular attention to the systematic uncertainties in these techniques and to strategies for controlling them at the level needed to exploit “Stage IV” dark energy facilities such as BigBOSS, LSST, Euclid, and WFIRST. We briefly review a number of other approaches including redshift-space distortions, the Alcock–Paczynski effect, and direct measurements of the Hubble constant H{sub 0}. We present extensive forecasts for constraints on the dark energy equation of state and parameterized deviations from General Relativity, achievable with Stage III and Stage IV experimental programs that incorporate supernovae, BAO, weak lensing, and cosmic microwave background data. We also show the level of precision required for clusters or other methods to provide constraints competitive with those of these fiducial programs. We emphasize the value of a balanced program that employs several of the most powerful methods in combination, both to cross-check systematic uncertainties and to take advantage of complementary information. Surveys to probe cosmic acceleration produce data sets that support a wide range of scientific investigations, and they continue the longstanding astronomical tradition of mapping the universe in ever greater detail over

  9. About cosmic gamma ray lines

    Science.gov (United States)

    Diehl, Roland

    2017-06-01

    Gamma ray lines from cosmic sources convey the action of nuclear reactions in cosmic sites and their impacts on astrophysical objects. Gamma rays at characteristic energies result from nuclear transitions following radioactive decays or high-energy collisions with excitation of nuclei. The gamma-ray line from the annihilation of positrons at 511 keV falls into the same energy window, although of different origin. We present here the concepts of cosmic gamma ray spectrometry and the corresponding instruments and missions, followed by a discussion of recent results and the challenges and open issues for the future. Among the lessons learned are the diffuse radioactive afterglow of massive-star nucleosynthesis in 26Al and 60Fe gamma rays, which is now being exploited towards the cycle of matter driven by massive stars and their supernovae; large interstellar cavities and superbubbles have been recognised to be of key importance here. Also, constraints on the complex processes making stars explode as either thermonuclear or core-collapse supernovae are being illuminated by gamma-ray lines, in this case from shortlived radioactivities from 56Ni and 44Ti decays. In particular, the three-dimensionality and asphericities that have recently been recognised as important are enlightened in different ways through such gamma-ray line spectroscopy. Finally, the distribution of positron annihilation gamma ray emission with its puzzling bulge-dominated intensity disctribution is measured through spatially-resolved spectra, which indicate that annihilation conditions may differ in different parts of our Galaxy. But it is now understood that a variety of sources may feed positrons into the interstellar medium, and their characteristics largely get lost during slowing down and propagation of positrons before annihilation; a recent microquasar flare was caught as an opportunity to see positrons annihilate at a source.

  10. Cosmic Rays in the Heliosphere: Requirements for Future Observations

    Science.gov (United States)

    Mewaldt, R. A.

    2013-06-01

    Since the publication of Cosmic Rays in the Heliosphere in 1998 there has been great progress in understanding how and why cosmic rays vary in space and time. This paper discusses measurements that are needed to continue advances in relating cosmic ray variations to changes in solar and interplanetary activity and variations in the local interstellar environment. Cosmic ray acceleration and transport is an important discipline in space physics and astrophysics, but it also plays a critical role in defining the radiation environment for humans and hardware in space, and is critical to efforts to unravel the history of solar activity. Cosmic rays are measured directly by balloon-borne and space instruments, and indirectly by ground-based neutron, muon and neutrino detectors, and by measurements of cosmogenic isotopes in ice cores, tree-rings, sediments, and meteorites. The topics covered here include: what we can learn from the deep 2008-2009 solar minimum, when cosmic rays reached the highest intensities of the space era; the implications of 10Be and 14C isotope archives for past and future solar activity; the effects of variations in the size of the heliosphere; opportunities provided by the Voyagers for discovering the origin of anomalous cosmic rays and measuring cosmic-ray spectra in interstellar space; and future space missions that can continue the exciting exploration of the heliosphere that has occurred over the past 50 years.

  11. Design of a simple magnetic spectrograph for the Karlsruhe isochronous cyclotron

    International Nuclear Information System (INIS)

    Gils, H.J.

    1980-12-01

    The ion-optical design of a simple magnetic spectrograph for studies of nuclear reactions on the Karlsruhe cyclotron is described. The spectrograph allows to determine the nuclear charge, the mass number, the reaction angle and the impulse (energy) of charged particles, which are emitted from the target. The spectrographs possibilities cover an appropriate range of likely nuclear reactions which are induced by light and heavy particles up to mass number A=20 and energies of 26 MeV per nucleon [de

  12. The Use of Color Sensors for Spectrographic Calibration

    Science.gov (United States)

    Thomas, Neil B.

    2018-04-01

    The wavelength calibration of spectrographs is an essential but challenging task in many disciplines. Calibration is traditionally accomplished by imaging the spectrum of a light source containing features that are known to appear at certain wavelengths and mapping them to their location on the sensor. This is typically required in conjunction with each scientific observation to account for mechanical and optical variations of the instrument over time, which may span years for certain projects. The method presented here investigates the usage of color itself instead of spectral features to calibrate a spectrograph. The primary advantage of such a calibration is that any broad-spectrum light source such as the sky or an incandescent bulb is suitable. This method allows for calibration using the full optical pathway of the instrument instead of incorporating separate calibration equipment that may introduce errors. This paper focuses on the potential for color calibration in the field of radial velocity astronomy, in which instruments must be finely calibrated for long periods of time to detect tiny Doppler wavelength shifts. This method is not restricted to radial velocity, however, and may find application in any field requiring calibrated spectrometers such as sea water analysis, cellular biology, chemistry, atmospheric studies, and so on. This paper demonstrates that color sensors have the potential to provide calibration with greatly reduced complexity.

  13. MSE spectrograph optical design: a novel pupil slicing technique

    Science.gov (United States)

    Spanò, P.

    2014-07-01

    The Maunakea Spectroscopic Explorer shall be mainly devoted to perform deep, wide-field, spectroscopic surveys at spectral resolutions from ~2000 to ~20000, at visible and near-infrared wavelengths. Simultaneous spectral coverage at low resolution is required, while at high resolution only selected windows can be covered. Moreover, very high multiplexing (3200 objects) must be obtained at low resolution. At higher resolutions a decreased number of objects (~800) can be observed. To meet such high demanding requirements, a fiber-fed multi-object spectrograph concept has been designed by pupil-slicing the collimated beam, followed by multiple dispersive and camera optics. Different resolution modes are obtained by introducing anamorphic lenslets in front of the fiber arrays. The spectrograph is able to switch between three resolution modes (2000, 6500, 20000) by removing the anamorphic lenses and exchanging gratings. Camera lenses are fixed in place to increase stability. To enhance throughput, VPH first-order gratings has been preferred over echelle gratings. Moreover, throughput is kept high over all wavelength ranges by splitting light into more arms by dichroic beamsplitters and optimizing efficiency for each channel by proper selection of glass materials, coatings, and grating parameters.

  14. Initial results from the fast imaging solar spectrograph (FISS)

    CERN Document Server

    2015-01-01

    This collection of papers describes the instrument and initial results obtained from the Fast Imaging Solar Spectrograph (FISS),  one of the post-focus instruments of the 1.6 meter New Solar Telescope at the Big Bear Solar Observatory. The FISS primarily aims at investigating structures and dynamics of  chromospheric features. This instrument is a dual-band Echelle spectrograph optimized for the simultaneous recording of the H I 656.3 nm band and the Ca II 854.2 nm band. The imaging is done with the fast raster scan realized by the linear motion of a two-mirror scanner, and its quality is determined by the performance of the adaptive optics of the telescope.    These papers illustrate the capability of the early FISS observations in the study of chromospheric features. Since the imaging quality has been improved a lot with the advance of the adaptive optics, one can obtain much better data with the current FISS observations.        This volume is aimed at graduate students and researchers working in...

  15. Cosmic perspectives in space physics

    CERN Document Server

    Biswas, Sukumar

    2000-01-01

    In the early years of the twentieth century, Victor Hess of Germany flew instruments in balloons and so discovered in 1912 that an extra-~errestial radiation of unknown origin is incident on the earth with an almost constant intensity at all times. These penetrating non­ solar radiations which were called Cosmic Rays by Millikan, USA, opened the new frontier of space physics and many leading scientists were attracted to it. At the end of World War II a number of space vehicles, e.g. stratospheric balloons, rockets and satellites were developed. In 1950 and onwards, these vehicles enabled spectacular advances in space physics and space astrophysics. New horizons were opened in the explorations of cosmic rays, the earth's magnetosphere, the Sun and the heliosphere, the moon and the planets. Using space-borne instruments, exciting discoveries were made of stars, and galaxies in the infra-red, ultra violet, x-ray and gamma-ray wavelengths. In this text book these fascinating new findings are presented in depth a...

  16. Electric currents in cosmic plasmas

    International Nuclear Information System (INIS)

    Alfven, H.

    1977-05-01

    Since the beginning of the century physics has been dualistic in the sense that some phenomena are described by a field concept, others by a particle concept. This dualism is essential also in the physics of cosmical plasmas: some phenomena should be described by a magnetic field formalism, others by an electric current formalism. During the first period of evolution of cosmic plasma physics the magnetic field aspect has dominated, and a fairly exhaustive description has been given of those phenomena--like the propagation of waves--which can be described in this way. We have now entered a second period which is dominated by a systematic exploration of the particle (or current) aspect. A survey is given of a number of phenomena which can be understood only from the particle aspect. These include the formation of electric double layers, the origin of explosive events like magnetic substorms and solar flares, and further, the transfer of energy from one region to another. A useful method of exploring many of these phenomena is to draw the electric circuit in which the current flows and study its properties. A number of simple circuits are analyzed in this way. (author)

  17. Cosmic ray modulation

    International Nuclear Information System (INIS)

    Ueno, Hirosachi

    1974-01-01

    It is important to know the physical state of solar plasma region by the observation of intensity variation of cosmic ray which passed through the solar plasma region, because earth magnetosphere is formed by the interaction between geomagnetic field and solar plasma flow. The observation of cosmic ray intensity is useful to know the average condition of the space of 0.1--3 A.U., and gives the structure of the magnetic field in solar wind affecting the earth magnetosphere. The observation of neutron component in cosmic ray has been carried out at Norikura, Tokyo, Fukushima and Morioka. The lower limit of the energy of incident cosmic ray which can be observed at each station is different, and the fine structure of the variation can be known by comparison. The intensity of meson component in cosmic ray has been measured in underground, and the state of solar plasma region 2--3 A.U. from the earth can be known. The underground measurement has been made at Takeyama and Matsumoto, and a new station at Sakashita is proposed. The measurement at Sakashita will be made by proportional counters at the depth of 100m (water equivalent). Arrangement of detectors is shown. (Kato, T.)

  18. Atmospheric ions and pollution. Ions of the cosmic radiation

    International Nuclear Information System (INIS)

    Cachon, A.

    1977-01-01

    The principal historical steps before the so-called 'cosmic radiation' was known as an extra-terrestrial radiation are described. The origin, nature and energy of the radiation are discussed together with its evolution all along its path through atmosphere, in view of the interaction that occurs between the radiation and the atmosphere. The mechanism of the ionization induced by cosmic radiation is analyzed, the corresponding energy balance is established and the possible singularities in air ionization induced by cosmic rays are discussed [fr

  19. Latest AMS Results on elementary particles in cosmic rays

    Science.gov (United States)

    Kounine, Andrei; AMS Collaboration

    2017-01-01

    AMS-02 is a particle physics detector collecting data on the International Space Station since May 2011. Precision measurements of all elementary charged cosmic ray particles have been performed by AMS using a data sample of 85 billion cosmic ray events collected during the first five years of operations on the Station. The latest AMS results on the fluxes and flux ratios of the elementary cosmic ray particles are presented. They show unique features that require accurate theoretical interpretation as to their origin, be it from dark matter collisions or new astrophysical sources. On behalf of the AMS Collaboration.

  20. Department of Cosmic Ray Physics - Overview

    International Nuclear Information System (INIS)

    Szabelski, J.

    2007-01-01

    The Department of Cosmic Ray Physics in Lodz is involved in basic research in the high energy Cosmic Ray field. Cosmic Rays are energetic particles from outside the Solar System. The energy spectrum (power law energy dependence) suggests non-thermal origin of these particles. Most of the studies of Cosmic Rays address fundamental problems: · the nature of the physical and astrophysical processes responsible for high energies of particles (up to about 1020 eV/particle), · an estimation of the astrophysical conditions at the acceleration sites and/or search for sources of Cosmic Rays, · properties of high energy particle interactions at very high energies (nuclear interactions at energies exceeding energy available in the laboratories). Some Cosmic Ray studies might have practical (commercial) implications, e.g.: · '' cosmic weather '' forecast - predictions of geomagnetic disturbances related to Solar activity changes (due to large Solar Flares / events of Coronal Mass Ejection); these are important for large electricity networks, gas pipes, radio-wave connections, space missions and satellite experiments. Presentation of Cosmic Ray registration to high school students becomes a popular way to introduce particle physics detectors and elementary particle detection techniques to young people. We organize in Lodz several workshops on particle physics for high school students. This is a part of European activity: Masterclass - Hands on CERN. Energetic Cosmic Ray particles produce cascades of particles in the atmosphere, called Extensive Air Showers (EAS). Registering EAS and their properties is the main way of experimental studies of very high energy Cosmic Rays. In Lodz Department we run Extensive Air Shower array where EAS are continuously being registered. We concentrate on the studies of detection of neutrons correlated with EAS and interpretation of this phenomenon. Back in 2004 we started realisation of the Roland Maze Project, the network of EAS detectors

  1. The science case of the PEPSI high-resolution echelle spectrograph and polarimeter for the LBT

    Science.gov (United States)

    Strassmeier, K. G.; Pallavicini, R.; Rice, J. B.; Andersen, M. I.

    2004-05-01

    We lay out the scientific rationale for and present the instrumental requirements of a high-resolution adaptive-optics Echelle spectrograph with two full-Stokes polarimeters for the Large Binocular Telescope (LBT) in Arizona. Magnetic processes just like those seen on the Sun and in the space environment of the Earth are now well recognized in many astrophysical areas. The application to other stars opened up a new field of research that became widely known as the solar-stellar connection. Late-type stars with convective envelopes are all affected by magnetic processes which give rise to a rich variety of phenomena on their surface and are largely responsible for the heating of their outer atmospheres. Magnetic fields are likely to play a crucial role in the accretion process of T-Tauri stars as well as in the acceleration and collimation of jet-like flows in young stellar objects (YSOs). Another area is the physics of active galactic nucleii (AGNs) , where the magnetic activity of the accreting black hole is now believed to be responsible for most of the behavior of these objects, including their X-ray spectrum, their notoriously dramatic variability, and the powerful relativistic jets they produce. Another is the physics of the central engines of cosmic gamma-ray bursts, the most powerful explosions in the universe, for which the extreme apparent energy release are explained through the collimation of the released energy by magnetic fields. Virtually all the physics of magnetic fields exploited in astrophysics is somehow linked to our understanding of the Sun's and the star's magnetic fields.

  2. A Shifting Shield Provides Protection Against Cosmic Rays

    Science.gov (United States)

    Kohler, Susanna

    2017-12-01

    The Sun plays an important role in protecting us from cosmic rays, energetic particles that pelt us from outside our solar system. But can we predict when and how it will provide the most protection, and use this to minimize the damage to both pilotedand roboticspace missions?The Challenge of Cosmic RaysSpacecraft outside of Earths atmosphere and magnetic field are at risk of damage from cosmic rays. [ESA]Galactic cosmic rays are high-energy, charged particles that originate from astrophysical processes like supernovae or even distant active galactic nuclei outside of our solar system.One reason to care about the cosmic rays arriving near Earth is because these particles can provide a significant challenge for space missions traveling above Earths protective atmosphere and magnetic field. Since impacts from cosmic rays can damage human DNA, this risk poses a major barrier to plans for interplanetary travel by crewed spacecraft. And roboticmissions arent safe either: cosmic rays can flip bits, wreaking havoc on spacecraft electronics as well.The magnetic field carried by the solar wind provides a protective shield, deflecting galactic cosmic rays from our solar system. [Walt Feimer/NASA GSFCs Conceptual Image Lab]Shielded by the SunConveniently, we do have some broader protection against galactic cosmic rays: a built-in shield provided by the Sun. The interplanetary magnetic field, which is embedded in the solar wind, deflects low-energy cosmic rays from us at the outer reaches of our solar system, decreasing the flux of these cosmic rays that reach us at Earth.This shield, however, isnt stationary; instead, it moves and changes as the strength and direction of the solar wind moves and changes. This results in a much lower cosmic-ray flux at Earth when solar activity is high i.e., at the peak of the 11-year solar cycle than when solar activity is low. This visible change in local cosmic-ray flux with solar activity is known as solar modulation of the cosmic ray flux

  3. Cosmic ray antimatter: Is it primary or secondary?

    Science.gov (United States)

    Stecker, F. W.; Protheroe, R. J.; Kazanas, D.

    1981-01-01

    The relative merits and difficulties of the primary and secondary origin hypotheses for the observed cosmic ray antiprotons, including the low energy measurement of Buffington, were examined. It is concluded that the cosmic ray antiproton data may be strong evidence for antimatter galaxies and baryon symmetric cosmology. The present antiproton data are consistent with a primary extragalactic component having antiproton/proton approximately equal to .0032 + or - 0.7.

  4. Cosmic Rays and Climate

    CERN Document Server

    Kirkby, Jasper

    2007-01-01

    Among the most puzzling questions in climate change is that of solar-climate variability, which has attracted the attention of scientists for more than two centuries. Until recently, even the existence of solar-climate variability has been controversial—perhaps because the observations had largely involved correlations between climate and the sunspot cycle that had persisted for only a few decades. Over the last few years, however, diverse reconstructions of past climate change have revealed clear associations with cosmic ray variations recorded in cosmogenic isotope archives, providing persuasive evidence for solar or cosmic ray forcing of the climate. However, despite the increasing evidence of its importance, solar-climate variability is likely to remain controversial until a physical mechanism is established. Although this remains a mystery, observations suggest that cloud cover may be influenced by cosmic rays, which are modulated by the solar wind and, on longer time scales, by the geomagnetic fiel...

  5. Cosmic strings and galaxy formation

    International Nuclear Information System (INIS)

    Bertschinger, E.

    1989-01-01

    Cosmic strings have become increasingly popular candidates as seeds for the formation of structure in the universe. This scenario, remains a serious cosmogonical model despite close scrutiny. In constrast, magnetic monopoles and domain walls - relic topological defects as are cosmic strings - are disastrous for cosmology if they are left over from the early universe. The production of heavy cosmic strings is speculative, as it depends on the details of ultrahigh energy physics. Fortunately, speculation about cosmic strings is not entirely idle because, if they exist and are heavy enough to seed galaxy formation, cosmic strings can be detected astronomically. Failure to detect cosmic strings would impose some constraints on grand unified theories (GUTs); their discovery would have exciting consequences for high energy physics and cosmology. This article reviews the basic physics of nonsuperconducting cosmic strings, highlighting the field theory aspects, and provides a progress report on calculations of structure formation with cosmic strings

  6. Ultrahigh-energy particles from cosmic strings

    International Nuclear Information System (INIS)

    Bhattacharjee, P.

    1991-02-01

    The idea of production of ultrahigh-energy particles in the present universe due to annihilation or collapse of topological defects is discussed. Topological defects, formed in symmetry-breaking phase transitions in the early universe, can survive till today owing to their topological stability. However, under certain circumstances, topological defects may be physically destroyed. When topological defects are destroyed, the energy contained in the defects can be released in the form of massive gauge- and Higgs bosons of the underlying spontaneously broken gauge theory. Subsequent decay of these massive particles can give rise to energetic particles ranging up to an energy on the order of the mass of the original particles released from the defects. This may give us a ''natural'' mechanism of production of extremely energetic cosmic ray particles in the universe today, without the need for any acceleration mechanism. To illustrate this idea, I describe in detail the calculation of the expected ultrahigh-energy proton spectrum due to a specific process which involves collapse or multiple self-intersections of a class of closed cosmic string loops formed in a phase transition at a grand unification energy scale. I discuss the possibility that some of the highest-energy cosmic ray particles are of this origin. By comparing with the observational results on the ultrahigh-energy cosmic rays, we derive an upper limit to the average fraction of the total energy in all ''primary'' cosmic string loops that may be released in the form of particles due to collapse or multiple self-intersections of these loops. No nuclei such as α's or Fe's are in the spectrum. 43 refs., 3 figs

  7. Search for cosmic-ray antimatter

    Science.gov (United States)

    Smoot, G. F.; Buffington, A.; Orth, C. D.

    1975-01-01

    It appears probable that some fraction of the cosmic rays has extragalactic origin. A search for antimatter nuclei was conducted with the aid of a balloon-borne superconducting magnetic spectrometer. The investigation made use of the fact that matter and antimatter nuclei, because of their opposite signs of charge, would be deflected in opposite directions when passing through a magnetic field. The antimatter flux limits set by the experiments are discussed.

  8. Cosmic Sum Rules

    DEFF Research Database (Denmark)

    T. Frandsen, Mads; Masina, Isabella; Sannino, Francesco

    2011-01-01

    We introduce new sum rules allowing to determine universal properties of the unknown component of the cosmic rays and show how it can be used to predict the positron fraction at energies not yet explored by current experiments and to constrain specific models.......We introduce new sum rules allowing to determine universal properties of the unknown component of the cosmic rays and show how it can be used to predict the positron fraction at energies not yet explored by current experiments and to constrain specific models....

  9. Educational Cosmic Ray Arrays

    International Nuclear Information System (INIS)

    Soluk, R. A.

    2006-01-01

    In the last decade a great deal of interest has arisen in using sparse arrays of cosmic ray detectors located at schools as a means of doing both outreach and physics research. This approach has the unique advantage of involving grade school students in an actual ongoing experiment, rather then a simple teaching exercise, while at the same time providing researchers with the basic infrastructure for installation of cosmic ray detectors. A survey is made of projects in North America and Europe and in particular the ALTA experiment at the University of Alberta which was the first experiment operating under this paradigm

  10. A disintegrating cosmic string

    International Nuclear Information System (INIS)

    Griffiths, J B; Docherty, P

    2002-01-01

    We present a simple sandwich gravitational wave of the Robinson-Trautman family. This is interpreted as representing a shock wave with a spherical wavefront which propagates into a Minkowski background minus a wedge (i.e. the background contains a cosmic string). The deficit angle (the tension) of the string decreases through the gravitational wave, which then ceases. This leaves an expanding spherical region of Minkowski space behind it. The decay of the cosmic string over a finite interval of retarded time may be considered to generate the gravitational wave. (letter to the editor)

  11. Heterotic cosmic strings

    International Nuclear Information System (INIS)

    Becker, Katrin; Becker, Melanie; Krause, Axel

    2006-01-01

    We show that all three conditions for the cosmological relevance of heterotic cosmic strings, the right tension, stability and a production mechanism at the end of inflation, can be met in the strongly coupled M-theory regime. Whereas cosmic strings generated from weakly coupled heterotic strings have the well-known problems posed by Witten in 1985, we show that strings arising from M5-branes wrapped around 4-cycles (divisors) of a Calabi-Yau in heterotic M-theory compactifications solve these problems in an elegant fashion

  12. Cosmic Humanity: Utopia, Realities, Prospects

    OpenAIRE

    Sergey Krichevsky

    2017-01-01

    The philosophical foundations of the theory and practice of the creation of cosmic humanity as a process of the evolution of human civilization, the emergence into space, with the prospect of resettlement outside the Earth are considered. There is a connection between myths, fantasies, ideas, concepts and projects aimed at the exploration of outer space, the creation of cosmic humanity. A new and voluminous definition of cosmic humanity in the evolutionary paradigm is given. Cosmic humanity i...

  13. A fast new cadioptric design for fiber-fed spectrographs

    Science.gov (United States)

    Saunders, Will

    2012-09-01

    The next generation of massively multiplexed multi-object spectrographs (DESpec, SUMIRE, BigBOSS, 4MOST, HECTOR) demand fast, efficient and affordable spectrographs, with higher resolutions (R = 3000-5000) than current designs. Beam-size is a (relatively) free parameter in the design, but the properties of VPH gratings are such that, for fixed resolution and wavelength coverage, the effect on beam-size on overall VPH efficiency is very small. For alltransmissive cameras, this suggests modest beam-sizes (say 80-150mm) to minimize costs; while for cadioptric (Schmidt-type) cameras, much larger beam-sizes (say 250mm+) are preferred to improve image quality and to minimize obstruction losses. Schmidt designs have benefits in terms of image quality, camera speed and scattered light performance, and recent advances such as MRF technology mean that the required aspherics are no longer a prohibitive cost or risk. The main objections to traditional Schmidt designs are the inaccessibility of the detector package, and the loss in throughput caused by it being in the beam. With expected count rates and current read-noise technology, the gain in camera speed allowed by Schmidt optics largely compensates for the additional obstruction losses. However, future advances in readout technology may erase most of this compensation. A new Schmidt/Maksutov-derived design is presented, which differs from previous designs in having the detector package outside the camera, and adjacent to the spectrograph pupil. The telescope pupil already contains a hole at its center, because of the obstruction from the telescope top-end. With a 250mm beam, it is possible to largely hide a 6cm × 6cm detector package and its dewar within this hole. This means that the design achieves a very high efficiency, competitive with transmissive designs. The optics are excellent, as least as good as classic Schmidt designs, allowing F/1.25 or even faster cameras. The principal hardware has been costed at $300K per

  14. Spectrographic analysis of metallic silicium and natural quartz

    International Nuclear Information System (INIS)

    Grigoletto, T.; Lordello, A.R.

    1985-01-01

    A method has been developed for the spectrographic determination of B, Mg, Al, Ca, Ti, Mn, Fe, Ni, Cu and Ag in silicon metal and other for Al, Ca, Mg, Ti, Cr, Mn, and Fe in natural quartz. A mixture of the matrix with a proper buffer is excited directly in a dc-arc. High-current (25A) and argon atmosphere are used for both the methods. Silicon metal is blended with 8% NaF and after 1:1 (w/w) with graphite. For natural quartz 20% NaF and 30% graphite by weight is the buffer mixture employed. The lower values in the determinations varies from 0.5 to 40 μg/g and the precision of the analysis from 7% to 45%. (Author) [pt

  15. Spectrographic analysis of waste waters; Analisis espectrografico de aguas residuales

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez Alduan, F; Capdevila, C

    1979-07-01

    The Influence of sodium and calcium, up to a maximum concentration of 1000 mg/1 Na and 300 mg/1 Ca, in the spectrographic determination of Cr, Cu, Fe,Mn and Pb in waste waters using graphite spark excitation has been studied. In order to eliminate this influence, each of the elements Ba, Cs, In, La, Li, Sr and Ti, as well as a mixture containing 5% Li-50% Ti, have been tested as spectrochemical buffers. This mixture allows to obtain an accuracy better than 25%. Sodium and calcium enhance the line intensities of impurities, when using graphite or gold electrodes, but they produce an opposite effect if copper or silver electrodes are used. (Author) 1 refs.

  16. Spectrographic determination of traces of boron in steels

    International Nuclear Information System (INIS)

    Alduan, F.A.; Roca, M.

    1976-01-01

    A spectrographic method has been developed to determine quantitatively boron in steels in the 0.5 to 250 ppm concentration range. The samples are dissolved in acids and transformed into oxides, avoiding boron losses by the addition of mannitol. For the fluoride evolution of boron in the dc arc the following compounds have been considered: CuF 2 , LiF, NaF, and SrF 2 . CuF 2 , at a concentration of 10%, provides the highest line-to-background intensity ratio. An arc current of 5 amperes eliminates the interference from iron spectrum on the most sensitive boron line - B 2497.7 A. Variations in chromium and nickel contents have no effect on the analytical results. (author)

  17. The vacuum system of the Karlsruhe magnetic spectrograph 'Little John'

    International Nuclear Information System (INIS)

    Buschmann, J.; Gils, H.J.; Jelitto, H.; Krisch, J.; Ludwig, G.; Manger, D.; Rebel, H.; Seith, W.; Zagromski, S.

    1985-02-01

    The vacuum equipment of the magnetic spectrograph Little John is described. The system is characterized by the following special features: The sliding exit flange of the target chamber can be moved to the desired angle of observation without affecting the high vacuum. The pressure maintained is less by a factor of ten than the pressure in the incoming beam tubing. The vacuum system is divided into several separate pumping sections. Ground loops are strictly avoided. All actual states of relevance are fed back to the control panels. The vacuum installation is protected by hardware interlocking systems as well as by a real time program written in FORTRAN in cooperation with CAMAC interfacing. (orig.) [de

  18. Determination of rare earth impurities in thorium by spectrographic methods

    Energy Technology Data Exchange (ETDEWEB)

    Wray, L W

    1957-08-15

    A method for determining rare earth impurities in thorium in the fractional ppm range is described. Before spectrographic examination is possible, the impurities must be freed from the thorium matrix. This is accomplished by removing the bulk of the thorium by extraction with TBP-CCl{sub 4} and the remainder by extraction with TTA-C{sub 6}H{sub 6}. This results in a consistent recovery of rare earths of about 85% with an average sensitivity of 0.2 ppm. The experimental error is within 10%. Details of the procedure are given together with working curves for the major neutron absorbing rare earths; i.e. dysprosium, europium, gadolinium and samarium. (author)

  19. Optical Design of the far Ultraviolet Imaging Spectrograph

    Directory of Open Access Journals (Sweden)

    K. S. Ryu

    1998-12-01

    Full Text Available We present the design specifications and the performance estimation of the FUVS (Far Ultraviolet Spectrograph proposed for the observations of aurora, day/night airglow and astronomical objects on small satelltes in the spectral range of . The design of FUVS is carried out with the full consideration of optical characteristics of the grating and the aspheric substrate. Two independent methods, ray-tracing and the wave front aberration theory, are employed to estimate the performance of the optical design and it is verified that both procedures yield the resolution of in the entire spectral range. MDF (Minimum Detectable Flux is also estimated using the known characteristics of the reflecting material and MCP, to study the feasibility of detection for faint emission lines from the hot interstellar plasmas. The results give that the observations from 1 day to 1 week, depending on the line intensity, can detect such faint emission lines from diffuse interstellar plasmas.

  20. Cosmic ray propagation with CRPropa 3

    International Nuclear Information System (INIS)

    Batista, R Alves; Evoli, C; Sigl, G; Van Vliet, A; Erdmann, M; Kuempel, D; Mueller, G; Walz, D; Kampert, K-H; Winchen, T

    2015-01-01

    Solving the question of the origin of ultra-high energy cosmic rays (UHECRs) requires the development of detailed simulation tools in order to interpret the experimental data and draw conclusions on the UHECR universe. CRPropa is a public Monte Carlo code for the galactic and extragalactic propagation of cosmic ray nuclei above ∼ 10 17 eV, as well as their photon and neutrino secondaries. In this contribution the new algorithms and features of CRPropa 3, the next major release, are presented. CRPropa 3 introduces time-dependent scenarios to include cosmic evolution in the presence of cosmic ray deflections in magnetic fields. The usage of high resolution magnetic fields is facilitated by shared memory parallelism, modulated fields and fields with heterogeneous resolution. Galactic propagation is enabled through the implementation of galactic magnetic field models, as well as an efficient forward propagation technique through transformation matrices. To make use of the large Python ecosystem in astrophysics CRPropa 3 can be steered and extended in Python. (paper)

  1. MEGARA: a new generation optical spectrograph for GTC

    Science.gov (United States)

    Gil de Paz, A.; Gallego, J.; Carrasco, E.; Iglesias-Páramo, J.; Cedazo, R.; Vílchez, J. M.; García-Vargas, M. L.; Arrillaga, X.; Carrera, M. A.; Castillo-Morales, A.; Castillo-Domínguez, E.; Eliche-Moral, M. C.; Ferrusca, D.; González-Guardia, E.; Lefort, B.; Maldonado, M.; Marino, R. A.; Martínez-Delgado, I.; Morales Durán, I.; Mujica, E.; Páez, G.; Pascual, S.; Pérez-Calpena, A.; Sánchez-Penim, A.; Sánchez-Blanco, E.; Tulloch, S.; Velázquez, M.; Zamorano, J.; Aguerri, A. L.; Barrado y Naváscues, D.; Bertone, E.; Cardiel, N.; Cava, A.; Cenarro, J.; Chávez, M.; García, M.; Guichard, J.; Gúzman, R.; Herrero, A.; Huélamo, N.; Hughes, D.; Jiménez-Vicente, J.; Kehrig, C.; Márquez, I.; Masegosa, J.; Mayya, Y. D.; Méndez-Abreu, J.; Mollá, M.; Muñoz-Tuñón, C.; Peimbert, M.; Pérez-González, P. G.; Pérez Montero, E.; Rodríguez, M.; Rodríguez-Espinosa, J. M.; Rodríguez-Merino, L.; Rosa-González, D.; Sánchez-Almeida, J.; Sánchez Contreras, C.; Sánchez-Blázquez, P.; Sánchez Moreno, F. M.; Sánchez, S. F.; Sarajedini, A.; Serena, F.; Silich, S.; Simón-Díaz, S.; Tenorio-Tagle, G.; Terlevich, E.; Terlevich, R.; Torres-Peimbert, S.; Trujillo, I.; Tsamis, Y.; Vega, O.; Villar, V.

    2014-07-01

    MEGARA (Multi-Espectrógrafo en GTC de Alta Resolución para Astronomía) is an optical Integral-Field Unit (IFU) and Multi-Object Spectrograph (MOS) designed for the GTC 10.4m telescope in La Palma. MEGARA offers two IFU fiber bundles, one covering 12.5x11.3 arcsec2 with a spaxel size of 0.62 arcsec (Large Compact Bundle; LCB) and another one covering 8.5x6.7 arcsec2 with a spaxel size of 0.42 arcsec (Small Compact Bundle; SCB). The MEGARA MOS mode will allow observing up to 100 objects in a region of 3.5x3.5 arcmin2 around the two IFU bundles. Both the LCB IFU and MOS capabilities of MEGARA will provide intermediate-to-high spectral resolutions (RFWHM~6,000, 12,000 and 18,700, respectively for the low-, mid- and high-resolution Volume Phase Holographic gratings) in the range 3650-9700ÅÅ. These values become RFWHM~7,000, 13,500, and 21,500 when the SCB is used. A mechanism placed at the pseudo-slit position allows exchanging the three observing modes and also acts as focusing mechanism. The spectrograph is a collimator-camera system that has a total of 11 VPHs simultaneously available (out of the 18 VPHs designed and being built) that are placed in the pupil by means of a wheel and an insertion mechanism. The custom-made cryostat hosts an E2V231-84 4kx4k CCD. The UCM (Spain) leads the MEGARA Consortium that also includes INAOE (Mexico), IAA-CSIC (Spain), and UPM (Spain). MEGARA is being developed under a contract between GRANTECAN and UCM. The detailed design, construction and AIV phases are now funded and the instrument should be delivered to GTC before the end of 2016.

  2. Hydrology and Cosmic radiation

    DEFF Research Database (Denmark)

    Andreasen, Mie

    and calibration. Yet, soil moisture measurements are traditionally provided on either point or kilometer scale from electromagnetic based sensors and satellite retrievals, respectively. Above the ground surface, the cosmic-ray neutron intensity (eV range) is inversely correlated to all hydrogen present...

  3. On the cosmical constant

    International Nuclear Information System (INIS)

    Chandra, R.

    1977-01-01

    On the grounds of the two correspondence limits, the Newtonian limit and the special theory limit of Einstein field equations, a modification of the cosmical constant has been proposed which gives realistic results in the case of a homogeneous universe. Also, according to this modification an explanation for the negative pressure in the steady-state model of the universe has been given. (author)

  4. Simulating Cosmic Reionisation

    NARCIS (Netherlands)

    Pawlik, Andreas Heinz

    2009-01-01

    The first stars formed a few hundred million years after the Big Bang, when the Universe was only a small fraction of its present age. Their radiation transformed the previously cold and neutral hydrogen that filled intergalactic space into the hot and ionised cosmic plasma that is observed today.

  5. Cosmic rays and climate

    CERN Multimedia

    2009-01-01

    Inside the new chamber the CLOUD team will be able to recreate the conditions of any part of the atmosphere, from the polar stratosphere to the low level tropics (top). The new chamber safely in position in the East hall. Once carefully cleaned the chamber will be turned sideways onto its legs ready for the beam of 'cosmic rays' (bottom).

  6. Note on cosmic censorship

    International Nuclear Information System (INIS)

    Jang, P.S.

    1979-01-01

    For initial data sets which represent charged black holes we prove some inequalities which relate the total energy, the total charge, and the size of the black hole. One of them is a necessary condition for the validity of cosmic censorship

  7. Use of an ultra-high resolution magnetic spectrograph for materials research

    NARCIS (Netherlands)

    Boerma, DO; Arnoldbik, WM; Wolfswinkel, W; Balogh, AG; Walter, G

    1997-01-01

    A brief description is given of a magnetic spectrograph for RBS and ERD analysis with MeV beams, delivered by a Tandem accelerator. With a number of examples of thin layer analysis it is shown that the spectrograph is uniquely suited for the measurement of concentration depth profiles up to a depth

  8. Tracing the cosmic web

    Science.gov (United States)

    Libeskind, Noam I.; van de Weygaert, Rien; Cautun, Marius; Falck, Bridget; Tempel, Elmo; Abel, Tom; Alpaslan, Mehmet; Aragón-Calvo, Miguel A.; Forero-Romero, Jaime E.; Gonzalez, Roberto; Gottlöber, Stefan; Hahn, Oliver; Hellwing, Wojciech A.; Hoffman, Yehuda; Jones, Bernard J. T.; Kitaura, Francisco; Knebe, Alexander; Manti, Serena; Neyrinck, Mark; Nuza, Sebastián E.; Padilla, Nelson; Platen, Erwin; Ramachandra, Nesar; Robotham, Aaron; Saar, Enn; Shandarin, Sergei; Steinmetz, Matthias; Stoica, Radu S.; Sousbie, Thierry; Yepes, Gustavo

    2018-01-01

    The cosmic web is one of the most striking features of the distribution of galaxies and dark matter on the largest scales in the Universe. It is composed of dense regions packed full of galaxies, long filamentary bridges, flattened sheets and vast low-density voids. The study of the cosmic web has focused primarily on the identification of such features, and on understanding the environmental effects on galaxy formation and halo assembly. As such, a variety of different methods have been devised to classify the cosmic web - depending on the data at hand, be it numerical simulations, large sky surveys or other. In this paper, we bring 12 of these methods together and apply them to the same data set in order to understand how they compare. In general, these cosmic-web classifiers have been designed with different cosmological goals in mind, and to study different questions. Therefore, one would not a priori expect agreement between different techniques; however, many of these methods do converge on the identification of specific features. In this paper, we study the agreements and disparities of the different methods. For example, each method finds that knots inhabit higher density regions than filaments, etc. and that voids have the lowest densities. For a given web environment, we find a substantial overlap in the density range assigned by each web classification scheme. We also compare classifications on a halo-by-halo basis; for example, we find that 9 of 12 methods classify around a third of group-mass haloes (i.e. Mhalo ∼ 1013.5 h-1 M⊙) as being in filaments. Lastly, so that any future cosmic-web classification scheme can be compared to the 12 methods used here, we have made all the data used in this paper public.

  9. Optical design and performance of a dual-grating, direct-reading spectrograph for spectrochemical analyses

    International Nuclear Information System (INIS)

    Steinhaus, D.W.; Kline, J.V.; Bieniewski, T.M.; Dow, G.S.; Apel, C.T.

    1979-01-01

    An all-mirror optical system is used to direct the light from a variety of spectroscopic sources to two 2-m spectrographs that are placed on either side of a sturdy vertical mounting plate. The gratings were chosen so that the first spectrograph covers the ultraviolet spectral region, and the second spectrograph covers the ultraviolet, visible, and near-infrared regions. With the over 2.5 m of focal curves, each ultraviolet line is available at more than one place. Thus, problems with close lines can be overcome. The signals from a possible maximum of 256 photoelectric detectors go to a small computer for reading and calculation of the element abundances. To our knowledge, no other direct-reading spectrograph has more than about 100 fixed detectors. With an inductively-coupled-plasma source, our calibration curves, and detection limits, are similar to those of other workers using a direct-reading spectrograph

  10. Optical Design And Performance Of A Dual-Grating, Direct-Reading Spectrograph For Spectrochemical Analyses

    Science.gov (United States)

    Steinhaus, David W.; Kline, John V.; Bieniewski, Thomas M.; Dow, Grove S.; Apel, Charles T.

    1980-11-01

    An all-mirror optical system is used to direct the light from a variety of spectroscopic sources to two 2-m spectrographs that are placed on either side of a sturdy vertical mounting plate. The gratings were chosen so that the first spectrograph covers the ultraviolet spectral region, and the second spectrograph covers the ultraviolet, visible, and near-infrared regions. With the over 2.5 m of focal curves, each ultraviolet line is available at more than one place. Thus, problems with close lines can be overcome. The signals from a possible maximum of 256 photoelectric detectors go to a small computer for reading and calculation of the element abundances. To our knowledge, no other direct-reading spectrograph has more than about 100 fixed detectors. With an inductively-coupled-plasma source, our calibration curves, and detection limits, are similar to those of other workers using a direct-reading spectrograph.

  11. Particle and astrophysics aspects of ultrahigh energy cosmic rays

    International Nuclear Information System (INIS)

    Sigl, G.

    2001-01-01

    The origin of cosmic rays is one of the major unresolved astrophysical questions. In particular, the highest energy cosmic rays observed possess macroscopic energies and their origin is likely to be associated with the most energetic processes in the Universe. Their existence triggered a flurry of theoretical explanations ranging from conventional shock acceleration to particle physics beyond the Standard Model and processes taking place at the earliest moments of our Universe. Furthermore, many new experimental activities promise a strong increase of statistics at the highest energies and a combination with γ-ray and neutrino astrophysics will put strong constraints on these theoretical models. Detailed Monte Carlo simulations indicate that charged ultra-high energy cosmic rays can also be used as probes of large scale magnetic fields whose origin may open another window into the very early Universe. We give an overview over this quickly evolving research field. (author)

  12. Particle and astrophysics aspects of ultrahigh energy cosmic rays

    Energy Technology Data Exchange (ETDEWEB)

    Sigl, G [Institut d' Astrophysique de Paris, Paris (France)

    2001-11-15

    The origin of cosmic rays is one of the major unresolved astrophysical questions. In particular, the highest energy cosmic rays observed possess macroscopic energies and their origin is likely to be associated with the most energetic processes in the Universe. Their existence triggered a flurry of theoretical explanations ranging from conventional shock acceleration to particle physics beyond the Standard Model and processes taking place at the earliest moments of our Universe. Furthermore, many new experimental activities promise a strong increase of statistics at the highest energies and a combination with {gamma}-ray and neutrino astrophysics will put strong constraints on these theoretical models. Detailed Monte Carlo simulations indicate that charged ultra-high energy cosmic rays can also be used as probes of large scale magnetic fields whose origin may open another window into the very early Universe. We give an overview over this quickly evolving research field. (author)

  13. Department of Cosmic Ray Physics - Overview

    International Nuclear Information System (INIS)

    Szabelski, J

    2005-01-01

    Full text: The Department of Cosmic Ray Physics in Lodz is involved in basic research in the high energy Cosmic Ray field. Cosmic Rays are energetic particles from outside the Solar System. The energy spectrum (power law energy dependence) suggests a non-thermal origin of these particles. Most studies of Cosmic Rays address fundamental problems: - the nature of the physical and astrophysical processes responsible for high energies of particles (up to about 10 20 eV/particle), - estimation of the astrophysical conditions at the acceleration sites and/or search for sources of Cosmic Rays, - properties of high energy particle interactions at very high energies (nuclear interactions at energies exceeding energy available in laboratories). - Some Cosmic Ray studies might have practical (commercial) implications, e.g. - ''cosmic weather'' forecast - predictions of geomagnetic disturbances related to Solar activity changes (due to large Solar Flares / events of Coronal Mass Ejection); these are important for large electricity networks, gas pipes, radio-wave connections, space missions and satellite experiments. Presentation of Cosmic Ray registration to high school students is a popular way to introduce particle physics detectors and elementary particle detection techniques to young people. Energetic Cosmic Ray particles produce cascades of particles in the atmosphere, called Extensive Air Showers (EAS). Registering the EAS and their properties is the main way of experimental studies of very high energy Cosmic Rays. In our Lodz Department we run an Extensive Air Shower array where EAS are continuously being registered. We concentrate on the studies of detection of neutrons correlated with EAS and interpretation of this phenomenon. In 2004 we started realisation of the Roland Maze Project, the network of EAS detectors placed on the roofs of high schools in Lodz. We received funds from the City of Lodz's budget to make a pilot project and equip 10 high schools, each with

  14. Department of Cosmic Ray Physics - Overview

    International Nuclear Information System (INIS)

    Szabelski, J.

    2006-01-01

    The Department of Cosmic Ray Physics in Lodz is involved in basic research in the high energy Cosmic Ray field. Cosmic Rays are energetic particles from outside the Solar System. The energy spectrum (power law energy dependence) suggests a non-thermal origin of these particles. Most of the studies of Cosmic Rays address fundamental problems: · The nature of the physical and astrophysical processes responsible for the high energies of the particles (up to about 1020 eV/particle), · An estimation of the astrophysical conditions at the acceleration sites and/or search for sources of Cosmic Rays, · properties of high energy particle interactions at very high energies (nuclear interactions at energies exceeding energy available in the laboratories). Some Cosmic Ray studies might have practical (commercial) implications, e.g. · 'cosmic weather' forecast - predictions of geomagnetic disturbances related to Solar activity changes (due to large Solar Flares / events of Coronal Mass Ejection); these are important for large electricity networks, gas pipes, radio-wave connections, space missions and satellite experiments. Presentation of Cosmic Ray registration to high school students becomes a popular way to introduce particle physics detectors and elementary particle detection techniques to young people. Energetic Cosmic Ray particles produce cascades of particles in the atmosphere, called Extensive Air Showers (EAS). Registering EAS and their properties is the main way of experimental studies of very high energy Cosmic Rays. In the Lodz Department we run the Extensive Air Shower array where EAS are being registered. We concentrate on the studies of detection of neutrons correlated with EAS and interpretation of this phenomenon. In 2004, we started realisation of the Roland Maze Project, the network of EAS detectors placed on roofs of high schools in Lodz. We received funds from the City of Lodz budget to make a pilot project and equip 10 high schools, each with four 1 m

  15. Cosmic Evolution: The History of an Idea

    Science.gov (United States)

    Dick, S. J.

    2004-12-01

    Cosmic evolution has become the conceptual framework within which modern astronomy is undertaken, and is the guiding principle of major NASA programs such as Origins and Astrobiology. While there are 19th- and early 20th century antecedents, as in the work of Robert Chambers, Herbert Spencer and Lawrence Henderson, it was only at mid-20th century that full-blown cosmic evolution began to be articulated and accepted as a research paradigm extending from the Big Bang to life, intelligence and the evolution of culture. Harlow Shapley was particularly important in spreading the idea to the public in the 1950s, and NASA embraced the idea in the 1970s as part of its SETI program and later its exobiology and astrobiology programs. Eric Chaisson, Carl Sagan and others were early proponents of cosmic evolution, and it continues to be elaborated in ever more subtle form as a research program and a philosophy. It has even been termed "Genesis for the 21st century." This paper documents the origin and development of the idea and offers a glimpse of where it could lead if cultural evolution is taken seriously, possibly leading to the concept of a postbiological universe.

  16. Atmospheric ionization and cosmic rays: studies and measurements before 1912

    Science.gov (United States)

    de Angelis, Alessandro

    2014-01-01

    The discovery of cosmic rays, a milestone in science, was based on the work by scientists in Europe and the New World and took place during a period characterized by nationalism and lack of communication. Many scientists that took part in this research a century ago were intrigued by the penetrating radiation and tried to understand the origin of it. Several important contributions to the discovery of the origin of cosmic rays have been forgotten; historical, political and personal facts might have contributed to their substantial disappearance from the history of science.

  17. Hazards of cosmic radiation

    International Nuclear Information System (INIS)

    Bonnet-Bidaud, J.M.; Dzitko, H.

    2000-06-01

    The main limitations on long-distance space transport is neither the energy source nor the propulsion system but appears to be the protection of cosmonauts from radiation. Cosmic radiation is made up of protons (87%), alpha particles (12%) and heavy nuclei (1%), all these particles travel through interstellar space and come from the explosion of stars at the end of their life. The earth is protected from cosmic radiation by 3 natural shields: i) the magnetic field generated by the solar wind, ii) the earth magnetic field (magnetosphere), and iii) the earth atmosphere, this elusive layer of air is equivalent to a 10 meter-high volume of water. Magnetosphere and atmosphere reduce the radiation dose by a factor 4000. According to a European directive (1996) air crews must be considered as radiation workers. (A.C.)

  18. Note on cosmic censorship

    International Nuclear Information System (INIS)

    Tipler, F.J.

    1985-01-01

    A number of recent theorems by Krolak and Newman purport to prove cosmic censorship by showing that ''strong curvature'' singularities must be hidden behind horizons. It is proved that Newman's ''null, strong curvature'' condition, which is imposed on certain classes of null geodesics to restrict curvature growth in the space-time, does not hold in many physically realistic space-times: it is not satisfied by any null geodesic in the relevant class in any open Friedmann cosmological model, nor does it hold for any null geodesic in the relevant class in maximal Schwarzschild space. More generally, it is argued that the singularity predicted by the Penrose singularity theorem is unlikely to be of the type eliminated by Newman. Thus the Newman theorems are probably without physical significance. The Krolak theorems, although based on a physically significant definition of strong curvature singularity, are mathematically invalid, and this approach cannot be used to obtain a cosmic censorship theorem. (author)

  19. Cosmic rays and climate

    CERN Multimedia

    CERN. Geneva

    2009-01-01

    The current understanding of climate change in the industrial age is that it is predominantly caused by anthropogenic greenhouse gases, with relatively small natural contributions due to solar irradiance and volcanoes. However, palaeoclimatic reconstructions show that the climate has frequently varied on 100-year time scales during the Holocene (last 10 kyr) by amounts comparable to the present warming - and yet the mechanism or mechanisms are not understood. Some of these reconstructions show clear associations with solar variability, which is recorded in the light radio-isotope archives that measure past variations of cosmic ray intensity. However, despite the increasing evidence of its importance, solar-climate variability is likely to remain controversial until a physical mechanism is established. Estimated changes of solar irradiance on these time scales appear to be too small to account for the climate observations. This raises the question of whether cosmic rays may directly affect the climate, provi...

  20. Cosmic Ray Mass Measurements with LOFAR

    Directory of Open Access Journals (Sweden)

    Buitink Stijn

    2017-01-01

    Full Text Available In the dense core of LOFAR individual air showers are detected by hundreds of dipole antennas simultaneously. We reconstruct Xmax by using a hybrid technique that combines a two-dimensional fit of the radio profile to CoREAS simulations and a one-dimensional fit of the particle density distribution. For high-quality detections, the statistical uncertainty on Xmax is smaller than 20 g/cm2. We present results of cosmic-ray mass analysis in the energy regime of 1017 - 1017.5 eV. This range is of particular interest as it may harbor the transition from a Galactic to an extragalactic origin of cosmic rays.

  1. The glacial cycles and cosmic rays

    CERN Document Server

    Kirkby, Jasper; Müller, R A

    2004-01-01

    The cause of the glacial cycles remains a mystery. The origin is widely accepted to be astronomical since paleoclimatic archives contain strong spectral components that match the frequencies of Earth's orbital modulation. Milankovitch insolation theory contains similar frequencies and has become established as the standard model of the glacial cycles. However, high precision paleoclimatic data have revealed serious discrepancies with the Milankovitch model that fundamentally challenge its validity and re-open the question of what causes the glacial cycles. We propose here that the ice ages are initially driven not by insolation cycles but by cosmic ray changes, probably through their effect on clouds. This conclusion is based on a wide range of evidence, including results presented here on speleothem growth in caves in Austria and Oman, and on a record of cosmic ray flux over the past 220 kyr obtained from the 10Be composition of deep-ocean sediments.

  2. Carl Sagan's Cosmic Connection

    Science.gov (United States)

    Sagan, Carl; Agel, Jerome

    2000-08-01

    Foreword Freeman Dyson; Personal reflections Ann Druyan; Preface; Part I. Cosmic Perspective: 1. A transitional animal; 2. The Unicorn of Cetus; 3. A message from earth; 4. A message to earth; 5. Experiments in utopias; 6. Chauvinism; 7. Space exploration as a human enterprise I. The scientific interest; 8. Space exploration as a human enterprise II. The public interest; 9. Space exploration as a human enterprise III. The historical interest; Part II. The Solar System: 10. On teaching the first grade; 11. 'The ancient and legendary Gods of old'; 12. The Venus detective story; 13. Venus is hell; 14. Science and 'intelligence'; 15. The moons of Barsoom; 16. The mountains of Mars I. Observations from earth; 17. The mountains of Mars II. Observations from space; 18. The canals of Mars; 19. The lost pictures of Mars; 20. The Ice Age and the cauldron; 21. Beginnings and ends of the Earth; 22. Terraforming the plants; 23. The exploration and utlization of the solar system; Part III. Beyond the Solar System: 24. Some of my best friends are dolphins; 25. 'Hello, central casting? Send me twenty extraterrestrials'; 26. The cosmic connection; 27. Extraterrestrial life: an idea whose time has come; 28. Has the Earth been visited?; 29. A search strategy for detecting extraterrestrial intelligence; 30. If we succeed 31. Cables, drums, and seashells; 32. The night freight to the stars; 33. Astroengineering; 34. Twenty questions: a classification of cosmic civilisations; 35. Galactic cultural exchanges; 36. A passage to elsewhere; 37. Starfolk I. A Fable; 38. Starfolk II. A future; 39. Starfolk III. The cosmic Cheshire cats; Epilog David Morrison; Index.

  3. Cosmic Rays in Thunderstorms

    Science.gov (United States)

    Buitink, Stijn; Scholten, Olaf; van den Berg, Ad; Ebert, Ute

    2013-04-01

    Cosmic Rays in Thunderstorms Cosmic rays are protons and heavier nuclei that constantly bombard the Earth's atmosphere with energies spanning a vast range from 109 to 1021 eV. At typical altitudes up to 10-20 km they initiate large particle cascades, called extensive air showers, that contain millions to billions of secondary particles depending on their initial energy. These particles include electrons, positrons, hadrons and muons, and are concentrated in a compact particle front that propagates at relativistic speed. In addition, the shower leaves behind a trail of lower energy electrons from ionization of air molecules. Under thunderstorm conditions these electrons contribute to the electrical and ionization processes in the cloud. When the local electric field is strong enough the secondary electrons can create relativistic electron run-away avalanches [1] or even non-relativistic avalanches. Cosmic rays could even trigger lightning inception. Conversely, strong electric fields also influence the development of the air shower [2]. Extensive air showers emit a short (tens of nanoseconds) radio pulse due to deflection of the shower particles in the Earth's magnetic field [3]. Antenna arrays, such as AERA, LOFAR and LOPES detect these pulses in a frequency window of roughly 10-100 MHz. These systems are also sensitive to the radiation from discharges associated to thunderstorms, and provide a means to study the interaction of cosmic ray air showers and the electrical processes in thunderstorms [4]. In this presentation we discuss the involved radiation mechanisms and present analyses of thunderstorm data from air shower arrays [1] A. Gurevich et al., Phys. Lett. A 165, 463 (1992) [2] S. Buitink et al., Astropart. Phys. 33, 1 (2010) [3] H. Falcke et al., Nature 435, 313 (2005) [4] S. Buitink et al., Astron. & Astrophys. 467, 385 (2007)

  4. Cosmic ray modulation

    Science.gov (United States)

    Agarwal Mishra, Rekha; Mishra, Rajesh Kumar

    2016-07-01

    Propagation of cosmic rays to and inside the heliosphere, encounter an outward moving solar wind with cyclic magnetic field fluctuation and turbulence, causing convection and diffusion in the heliosphere. Cosmic ray counts from the ground ground-based neutron monitors at different cut of rigidity show intensity changes, which are anti-correlated with sunspot numbers. They also lose energy as they propagate towards the Earth and experience various types of modulations due to different solar activity indices. In this work, we study the first three harmonics of cosmic ray intensity on geo-magnetically quiet days over the period 1965-2014 for Beijing, Moscow and Tokyo neutron monitoring stations located at different cut off rigidity. The amplitude of first harmonic remains high for low cutoff rigidity as compared to high cutoff rigidity on quiet days. The diurnal amplitude significantly decreases during solar activity minimum years. The diurnal time of maximum significantly shifts to an earlier time as compared to the corotational direction having different cutoff rigidities. The time of maximum for first harmonic significantly shifts towards later hours and for second harmonic it shifts towards earlier hours at low cutoff rigidity station as compared to the high cut off rigidity station on quiet days. The amplitude of second/third harmonics shows a good positive correlation with solar wind velocity, while the others (i.e. amplitude and phase) have no significant correlation on quiet days. The amplitude and direction of the anisotropy on quiet days does not show any significant dependence on high-speed solar wind streams for these neutron monitoring stations of different cutoff rigidity threshold. Keywords: cosmic ray, cut off rigidity, quiet days, harmonics, amplitude, phase.

  5. Design and realization of the real-time spectrograph controller for LAMOST based on FPGA

    Science.gov (United States)

    Wang, Jianing; Wu, Liyan; Zeng, Yizhong; Dai, Songxin; Hu, Zhongwen; Zhu, Yongtian; Wang, Lei; Wu, Zhen; Chen, Yi

    2008-08-01

    A large Schmitt reflector telescope, Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST), is being built in China, which has effective aperture of 4 meters and can observe the spectra of as many as 4000 objects simultaneously. To fit such a large amount of observational objects, the dispersion part is composed of a set of 16 multipurpose fiber-fed double-beam Schmidt spectrographs, of which each has about ten of moveable components realtimely accommodated and manipulated by a controller. An industrial Ethernet network connects those 16 spectrograph controllers. The light from stars is fed to the entrance slits of the spectrographs with optical fibers. In this paper, we mainly introduce the design and realization of our real-time controller for the spectrograph, our design using the technique of System On Programmable Chip (SOPC) based on Field Programmable Gate Array (FPGA) and then realizing the control of the spectrographs through NIOSII Soft Core Embedded Processor. We seal the stepper motor controller as intellectual property (IP) cores and reuse it, greatly simplifying the design process and then shortening the development time. Under the embedded operating system μC/OS-II, a multi-tasks control program has been well written to realize the real-time control of the moveable parts of the spectrographs. At present, a number of such controllers have been applied in the spectrograph of LAMOST.

  6. Angular correlation of cosmic neutrinos with ultrahigh-energy cosmic rays and implications for their sources

    Energy Technology Data Exchange (ETDEWEB)

    Moharana, Reetanjali; Razzaque, Soebur, E-mail: reetanjalim@uj.ac.za, E-mail: srazzaque@uj.ac.za [Department of Physics, University of Johannesburg, P.O. Box 524, Auckland Park 2006 (South Africa)

    2015-08-01

    Cosmic neutrino events detected by the IceCube Neutrino Observatory with energy 0∼> 3 TeV have poor angular resolutions to reveal their origin. Ultrahigh-energy cosmic rays (UHECRs), with better angular resolutions at 0>6 EeV energies, can be used to check if the same astrophysical sources are responsible for producing both neutrinos and UHECRs. We test this hypothesis, with statistical methods which emphasize invariant quantities, by using data from the Pierre Auger Observatory, Telescope Array and past cosmic-ray experiments. We find that the arrival directions of the cosmic neutrinos are correlated with 0≥ 10 EeV UHECR arrival directions at confidence level ≈ 90%. The strength of the correlation decreases with decreasing UHECR energy and no correlation exists at energy 0∼ 6 EeV . A search in astrophysical databases within 3{sup o} of the arrival directions of UHECRs with energy 0≥ 10 EeV, that are correlated with the IceCube cosmic neutrinos, resulted in 18 sources from the Swift-BAT X-ray catalog with redshift z≤ 0.06. We also found 3 objects in the Kühr catalog of radio sources using the same criteria. The sources are dominantly Seyfert galaxies with Cygnus A being the most prominent member. We calculate the required neutrino and UHECR fluxes to produce the observed correlated events, and estimate the corresponding neutrino luminosity (25 TeV–2.2 PeV) and cosmic-ray luminosity (500 TeV–180 EeV), assuming the sources are the ones we found in the Swift-BAT and Kühr catalogs. We compare these luminosities with the X-ray luminosity of the corresponding sources and discuss possibilities of accelerating protons to 0∼> 10 EeV and produce neutrinos in these sources.

  7. Spectrographic determination of impurities in ammonium bifluoride. IV.Study of the processes of vaporization, transport and excitation of the elements Fe, Mn, Mo, Ni, Pb and Si

    International Nuclear Information System (INIS)

    Alduan, F.A.; Capdevila, C.; Roca, M.

    1981-01-01

    The influences of the processes of vaporization, transport and excitation on the shape of the volatilization-excitation curves and on the values of the spectra-line intensities have been investigated in a method for the spectrographic determination of Fe, Mn, Mo, Ni, Pb and Si in ammonium bifluoride samples by direct current arc Ga 2 O 3 , GeO 2 , MgO and ZnO. The reaction products in the electrode cavity have been identified by X-ray powder diffraction analysis and the porcentages of vaporized and diffused element evaluated through analysis by total-burning spectrographic methods. In addition, the values of both the number of particles entering the discharge column and the transport efficiencies have been calculated. Thus, the origin of most observed differences has been explained. (author)

  8. Gemini Near Infrared Field Spectrograph Observations of the Seyfert 2 Galaxy MRK 573: In Situ Acceleration of Ionized and Molecular Gas Off Fueling Flows

    Science.gov (United States)

    Fischer, Travis C.; Machuca, C.; Diniz, M. R.; Crenshaw, D. M.; Kraemer, S. B.; Riffel, R. A.; Schmitt, H. R.; Baron, F.; Storchi-Bergmann, T.; Straughn, A. N.; hide

    2016-01-01

    We present near-infrared and optical emission-line and stellar kinematics of the Seyfert 2 galaxy Mrk 573 using the Near-Infrared Field Spectrograph (NIFS) at Gemini North and Dual Imaging Spectrograph at Apache Point Observatory, respectively. By obtaining full kinematic maps of the infrared ionized and molecular gas and stellar kinematics in approximately 700 x 2100 pc(exp 2) circumnuclear region of Mrk 573, we find that kinematics within the Narrow-Line Region are largely due to a combination of both rotation and in situ acceleration of material originating in the host disk. Combining these observations with large-scale, optical long-slit spectroscopy that traces ionized gas emission out to several kpcs, we find that rotation kinematics dominate the majority of the gas. We find that outflowing gas extends to distances less than 1 kpc, suggesting that outflows in Seyfert galaxies may not be powerful enough to evacuate their entire bulges.

  9. Spectrographic determination of impurities in ammonium bifluoride. III. Study of the processes of vaporization, transport and excitation of the elements Al, B, Cu and Cr

    International Nuclear Information System (INIS)

    Alduan, F. A.; Roca, M.; Capdevila, C.

    1979-01-01

    The influences of the processes of vaporization, transport and excitation on the shape of the volatilization-excitation curves and on the values of the spectral-line intensities have been investigated in a method for the spectrographic determination of Al, B, Cu and Cr In ammonium bifluoride samples by direct current are excitation in Scribner type electrodes, with addition of different matrices (graphite, 63203, GeO 2 , MgO and Zn0). The reaction products in the electrode cavity have been identified by X-ray powder diffraction analysis and the percentages of vaporized and diffused element evaluated through analysis by total-burning spectrographic methods. In addition, the values of both the number of particles entering the discharge column and the transport efficiencies have been calculated. Thus, the origin of most observed differences has been explained. (Author) 11 refs

  10. Nucleosynthesis in Wolf-Rayet stars and galactic cosmic-ray isotopic composition

    International Nuclear Information System (INIS)

    Prantzos, N.

    1984-01-01

    An explanation of the isotopic composition of galactic cosmic rays could provide some clues to the mystery of their origin. It seems now that the strong stellar winds of Wolf-Rayet stars could account for most of the isotopic anomalies that have been observed in cosmic rays. Some results are presented, obtained by detailed nucleosynthesis computations. 25 references

  11. Ultra high energy cosmic rays above 10 GeV: Hints to new physics ...

    Indian Academy of Sciences (India)

    Ultra high energy cosmic rays; physics beyond standard model. ... The origin of the observed cosmic ray (CR) events above 10ѕј eV — the so-called ex- .... to arise simply from decay of some supermassive particles (of mass> 10ѕЅ eV) ...

  12. Ultra-high energy cosmic rays and prompt TeV gamma rays from ...

    Indian Academy of Sciences (India)

    physics pp. 789-792. Ultra-high energy cosmic rays and prompt. TeV gamma rays from gamma ray bursts ... The origin of the observed ultra-high energy cosmic ray (UHECR) events with ... are proton and electron rest mass, respectively.

  13. Cosmic-ray produced nuclides in ground level air and in precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Schumann, G.; Roedel, W.; Stoeppler, M.

    1963-11-15

    There are mainly three kinds of radioactive substances in the atmosphere: emanations from the ground and their daughters, nuclides produced in the atmosphere by cosmic rays, and artificial products originating from nuclear weapon tests (and in a very small amount from other nuclear technical applications). This paper deals in particular with some of the cosmic-ray produced nuclides.

  14. Two Solar Tornadoes Observed with the Interface Region Imaging Spectrograph

    Science.gov (United States)

    Yang, Zihao; Tian, Hui; Peter, Hardi; Su, Yang; Samanta, Tanmoy; Zhang, Jingwen; Chen, Yajie

    2018-01-01

    The barbs or legs of some prominences show an apparent motion of rotation, which are often termed solar tornadoes. It is under debate whether the apparent motion is a real rotating motion, or caused by oscillations or counter-streaming flows. We present analysis results from spectroscopic observations of two tornadoes by the Interface Region Imaging Spectrograph. Each tornado was observed for more than 2.5 hr. Doppler velocities are derived through a single Gaussian fit to the Mg II k 2796 Å and Si IV 1393 Å line profiles. We find coherent and stable redshifts and blueshifts adjacent to each other across the tornado axes, which appears to favor the interpretation of these tornadoes as rotating cool plasmas with temperatures of 104 K–105 K. This interpretation is further supported by simultaneous observations of the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory, which reveal periodic motions of dark structures in the tornadoes. Our results demonstrate that spectroscopic observations can provide key information to disentangle different physical processes in solar prominences.

  15. Calibrating the SNfactory Integral Field Spectrograph (SNIFS) with SCALA

    Science.gov (United States)

    Küsters, Daniel; Lombardo, Simona; Kowalski, Marek; Aldering, Greg; Nordin, Jakob; Rigault, Mickael

    2016-08-01

    The SNIFS CALibration Apparatus (SCALA), a device to calibrate the Supernova Integral Field Spectrograph on the University Hawaii 2.2m telescope, was developed and installed in Spring 2014. SCALA produces an artificial planet with a diameter of 1° and a constant surface brightness. The wavelength of the beam can be tuned between 3200 Å and 10000 Å and has a bandwidth of 35 Å. The amount of light injected into the telescope is monitored with NIST calibrated photodiodes. SCALA was upgraded in 2015 with a mask installed at the entrance pupil of the UH88 telescope, ensuring that the illumination of the telescope by stars is similar to that of SCALA. With this setup, a first calibration run was performed in conjunction with the spectrophotometric observations of standard stars. We present first estimates for the expected systematic uncertainties of the in-situ calibration and discuss the results of tests that examine the influence of stray light produced in the optics.

  16. SCALA: In situ calibration for integral field spectrographs

    Science.gov (United States)

    Lombardo, S.; Küsters, D.; Kowalski, M.; Aldering, G.; Antilogus, P.; Bailey, S.; Baltay, C.; Barbary, K.; Baugh, D.; Bongard, S.; Boone, K.; Buton, C.; Chen, J.; Chotard, N.; Copin, Y.; Dixon, S.; Fagrelius, P.; Feindt, U.; Fouchez, D.; Gangler, E.; Hayden, B.; Hillebrandt, W.; Hoffmann, A.; Kim, A. G.; Leget, P.-F.; McKay, L.; Nordin, J.; Pain, R.; Pécontal, E.; Pereira, R.; Perlmutter, S.; Rabinowitz, D.; Reif, K.; Rigault, M.; Rubin, D.; Runge, K.; Saunders, C.; Smadja, G.; Suzuki, N.; Taubenberger, S.; Tao, C.; Thomas, R. C.; Nearby Supernova Factory

    2017-11-01

    Aims: The scientific yield of current and future optical surveys is increasingly limited by systematic uncertainties in the flux calibration. This is the case for type Ia supernova (SN Ia) cosmology programs, where an improved calibration directly translates into improved cosmological constraints. Current methodology rests on models of stars. Here we aim to obtain flux calibration that is traceable to state-of-the-art detector-based calibration. Methods: We present the SNIFS Calibration Apparatus (SCALA), a color (relative) flux calibration system developed for the SuperNova integral field spectrograph (SNIFS), operating at the University of Hawaii 2.2 m (UH 88) telescope. Results: By comparing the color trend of the illumination generated by SCALA during two commissioning runs, and to previous laboratory measurements, we show that we can determine the light emitted by SCALA with a long-term repeatability better than 1%. We describe the calibration procedure necessary to control for system aging. We present measurements of the SNIFS throughput as estimated by SCALA observations. Conclusions: The SCALA calibration unit is now fully deployed at the UH 88 telescope, and with it color-calibration between 4000 Å and 9000 Å is stable at the percent level over a one-year baseline.

  17. Spectrographic study of λ 4200 silicon particular stars

    International Nuclear Information System (INIS)

    Didelon, Pierre

    1983-01-01

    This research thesis reports a spectrographic study of sample of particular stars belonging to the Si(II) λ 4200 subgroup which builds up the hot end of conventional 'Ap,Bp' stars. Twenty snapshots taken at the Haute-Provence observatory have been studied and compared with the observation of 17 standard stars. All these snapshots have been digitalised and processed. This allowed the identification of lines which indicated the presence of gallium and the absence of manganese which contradicts the close correlation between these elements that was generally admitted. An inexplicable and until now non observed duplication of Si(II) lines has also been observed. The problem of spectral classification of these stars has been studied. In order to study the concerned stars without calculation of atmospheric models, a comparative method between group stars and reference stars has been used. Results are discussed and seem to indicate an erratic and non-correlated behaviour of light elements (C, Mg, Ca, Si), and a presence of heavier elements (Ga, Sr) and rare earths (Eu, Gd) only when elements of the iron peak are stronger [fr

  18. Spectrographic determination of some rare earths in thorium compounds

    International Nuclear Information System (INIS)

    Brito, J. de.

    1977-01-01

    A method for spectrographic determination of Gd, Sm, Dy, Eu, Y, Yb, Tm and Lu in thorium compounds has been developed. Sensibilities of 0.01 μg rare earths/g Th02 were achieved. The rare earth elements were chromatographycally separated in a nitric acid-ether-cellulose system. The solvent mixture was prepared by dissolving 11% of concentrated nitric acid in ether. The method is based upon the sorption of the rare earths on activated cellulose, the elements being eluted together with 0.01 M HNO 3 . The retention of the 152 , 154 Eu used as tracer was 99,4%. The other elements showed recoveries varying from 95 to 99%. A direct carrier destillation procedure for the spectrochemical determination of the mentioned elements was used. Several concentrations of silver chloride were used to study the volatility behavior of the rare earths. 2%AgCl was added to the matrix as definite carrier, being lantanum selected as internal standard. The average coefficient of variation for this method was +- -+ 7%. The method has been appleid to the analysis of rare earths in thorium coumpounds prepared by Thorium Purification Pilot Plant at Atomic Energy Institute, Sao Paulo [pt

  19. Caustic Skeleton & Cosmic Web

    Science.gov (United States)

    Feldbrugge, Job; van de Weygaert, Rien; Hidding, Johan; Feldbrugge, Joost

    2018-05-01

    We present a general formalism for identifying the caustic structure of a dynamically evolving mass distribution, in an arbitrary dimensional space. The identification of caustics in fluids with Hamiltonian dynamics, viewed in Lagrangian space, corresponds to the classification of singularities in Lagrangian catastrophe theory. On the basis of this formalism we develop a theoretical framework for the dynamics of the formation of the cosmic web, and specifically those aspects that characterize its unique nature: its complex topological connectivity and multiscale spinal structure of sheetlike membranes, elongated filaments and compact cluster nodes. Given the collisionless nature of the gravitationally dominant dark matter component in the universe, the presented formalism entails an accurate description of the spatial organization of matter resulting from the gravitationally driven formation of cosmic structure. The present work represents a significant extension of the work by Arnol'd et al. [1], who classified the caustics that develop in one- and two-dimensional systems that evolve according to the Zel'dovich approximation. His seminal work established the defining role of emerging singularities in the formation of nonlinear structures in the universe. At the transition from the linear to nonlinear structure evolution, the first complex features emerge at locations where different fluid elements cross to establish multistream regions. Involving a complex folding of the 6-D sheetlike phase-space distribution, it manifests itself in the appearance of infinite density caustic features. The classification and characterization of these mass element foldings can be encapsulated in caustic conditions on the eigenvalue and eigenvector fields of the deformation tensor field. In this study we introduce an alternative and transparent proof for Lagrangian catastrophe theory. This facilitates the derivation of the caustic conditions for general Lagrangian fluids, with

  20. Auroral spectrograph data annals of the international geophysical year, v.25

    CERN Document Server

    Carrigan, Anne; Norman, S J

    1964-01-01

    Annals of the International Geophysical Year, Volume 25: Auroral Spectrograph Data is a five-chapter text that contains tabulations of auroral spectrograph data. The patrol spectrograph built by the Perkin-Elmer Corporation for the Aurora and Airglow Program of the IGY is a high-speed, low-dispersion, automatic instrument designed to photograph spectra of aurora occurring along a given magnetic meridian of the sky. Data from each spectral frame were recorded on an IBM punched card. The data recorded on the cards are printed onto the tabulations in this volume. These tabulations are available

  1. Cosmic Education: Formation of a Planetary and Cosmic Personality

    Directory of Open Access Journals (Sweden)

    Bazaluk Oleg

    2012-04-01

    Full Text Available The major stages of development of cosmic pedagogy have been researched. Based on the achievements of the modern neurosciences as well as of psychology, cosmology, and philosophy, the authors provide their reasoning for the cosmic education and its outlooks for the educational systems of the world. Through the studies of how important human mind is for the Earth and the cosmos and by researching the evolution of human mind within the structure of the Universe, the authors create a more advanced scientific and philosophic basis for the cosmic education where the subject is a comprehensive process of formation and directed progress of both an individual mind and a conglomerate of minds called the "psychospace". The cosmic education researches the permanent progress of the intelligent matter of the Earth. The purpose of the cosmic education has been determined as formation of a planetary and cosmic personality. According to the authors, a planetary and cosmic personality is a harmony of mind, soul, and body, and such harmony is directed to use the internal creative potential of mind to the benefit of the intelligent matter of the entire Earth and the cosmos. The properties of such a planetary and cosmic personality are being improved continuously; they are a sample (the ideal of the cosmic pedagogy and the image of a human being of the future. Through the usage of the entire potential and art of upbringing and educating, the cosmic pedagogy is called to embody the major properties of the image of a human being of the future in the new generations of minds and to form a planetary and cosmic personality capable of self-actualization to the benefit of the permanent progress of the intelligent matter.

  2. Trek and ECCO: Abundance measurements of ultraheavy galactic cosmic rays

    International Nuclear Information System (INIS)

    Westphal, Andrew J.

    2000-01-01

    Using the Trek detector, we have measured the abundances of the heaviest elements (with Z>70) in the galactic cosmic rays with sufficient charge resolution to resolve the even-Z elements. We find that the abundance of Pb compared to Pt is ∼3 times lower than the value expected from the most widely-held class of models of the origin of galactic cosmic ray nuclei, that is, origination in a partially ionized medium with solar-like composition. The low abundance of Pb is, however, consistent with the interstellar gas and dust model of Meyer, Drury and Ellison, and with a source enriched in r-process material, proposed by Binns et al. A high-resolution, high-statistics measurement of the abundances of the individual actinides would distinguish between these models. This is the goal of ECCO, the Extremely Heavy Cosmic-ray Composition Observer, which we plan to deploy on the International Space Station

  3. Cosmic Rays from the Knee to the Ankle

    Science.gov (United States)

    Haungs, Andreas

    Investigations of the energy spectrum as well as the mass composition of cosmic rays in the energy range of PeV to EeV are important for understanding both, the origin of the galactic and the extragalactic cosmic rays. Recently, three modern experimental installations (KASCADE-Grande, IceTop, Tunka-133), dedicated to investigate this primary energy range, have published new results on the all-particle energy spectrum. In this short review these results are presented and the similarities and differences discussed. In addition, the effects of using different hadronic interaction models for interpreting the measured air-shower data will be examined. Finally, a brief discussion on the question if the present results are in agreement or in contradiction with astrophysical models for the transition from galactic to extragalactic origin of cosmic rays completes this paper.

  4. Correlation between ionospheric potential and the intensity of cosmic rays

    International Nuclear Information System (INIS)

    Meyerott, R.E.; Reagan, J.B.; Evans, J.E.

    1983-01-01

    Ionospheric potential variations with a period of about 10 yr have been observed in the data that have been acquired to date. Previous studies have shown that these variations appear to be correlated inversely with sunspot number and with solar wind velocity, and directly with cosmic ray intensity. Since the cosmic ray intensity is inversely correlated with sunspot number and solar wind velocity, these correlations all suggest that the long period variations are of solar origin. In this report it is shown that, over the limited period for which ionospheric potential measurements exist, the long period variations are better correlated with the aerosol burden injected into the stratosphere by large volcanic eruptions than with the intensity of cosmic rays. This result indicates that the long period variations in ionospheric potential are of terrestrial rather than solar origin. 20 references

  5. Highlights from e-EPS: Cosmic Day / FEL for SuperB / Assessment Assessed

    CERN Multimedia

    Ian Randall, Bénédicte Huchet and EPS

    2012-01-01

    e-EPS News is a monthly addition to the CERN Bulletin line-up, showcasing articles from e-EPS – the European Physical Society newsletter – as part of a collaboration between the two publications.   International Cosmic Day The first International Cosmic Day will be held on 26 September this year. During this event, students and teachers worldwide will come together in research institutions, universities and classrooms to learn about cosmic particle research. The event will celebrate the centenary of Victor Franz Hess’ discovery of cosmic rays – particles which originate in outer space and spread through the whole universe, often at extremely high energies. On the day, students will tackle such questions as: what are cosmic particles? … where do they come from? … and how can they be measured? Participants will be encouraged to undertake their own cosmic particle experiments: analysing and evaluating the...

  6. MARS A Cosmic Stepping Stone Uncovering Humanity’s Cosmic Context

    CERN Document Server

    Nolan, Kevin

    2008-01-01

    The questions of our origin and cosmic abundance of life are among the most compelling facing humanity. We have determined much about the nature and origin of the Universe and our place in it, but with virtually all evidence of our origin long since gone from our world and an unimaginably vast Universe still to explore, defining answers are difficult to obtain. For all of the difficulties facing us however, the planet Mars may act as a ‘cosmic stepping stone’ in uncovering some of the answers. Although different today, the origin and early history of both Earth and Mars may have been similar enough to consider an origin to life on both. But because Mars’ planetary processes collapsed over three billion years ago – just as life was beginning to flourish on Earth – a significant and unique record of activity from that era perhaps relevant to the origin of life still resides there today. In recognition of this, both the US and Europe are currently engaged in one of the most ambitious programs of explor...

  7. Exceptional Colloquium: The Rise, Fall, and Rebirth of Cosmic Strings

    CERN Multimedia

    CERN. Geneva; Treille, D; Alvarez-Gaumé, Luís

    2005-01-01

    In the 1980s many people were excited by the concept that cosmic strings, as relics of the Grand Unified Era, could be responsible for the formation of cosmic structure. In the 1990s the cosmic string concept steadily lost ground to the Inflationary model both as a result of the difficulty of calculations and more definitively through observations of the CMB. About the time many expected the new WMAP data to deliver the coup de grace, the concepts of cosmic strings as major physical phenomena (not so important in structure formation) has begun a renaissance. This new interest is motivated by one of the original ideas that topological defects are inevitable in symmetry breaking by the Kibble (1976) mechanism and the introduction of new ideas such as brane-cosmology/inflation and the realization that cosmic strings may be the only acceptable such defect. We find ourselves back in the business of trying to detect or limit and understand cosmic strings once again for the insight and constraints they put on partic...

  8. Exceptional Colloquium: The Rise, Fall, and Rebirth of Cosmic Strings

    CERN Multimedia

    CERN. Geneva

    2005-01-01

    In the 1980s many people were excited by the concept that cosmic strings, as relics of the Grand Unified Era, could be responsible for the formation of cosmic structure. In the 1990s the cosmic string concept steadily lost ground to the Inflationary model both as a result of the difficulty of calculations and more definitively through observations of the CMB. About the time many expected the new WMAP data to deliver the coup de grace, the concepts of cosmic strings as major physical phenomena (not so important in structure formation) has begun a renaissance. This new interest is motivated by one of the original ideas that topological defects are inevitable in symmetry breaking by the Kibble (1976) mechanism and the introduction of new ideas such as brane-cosmology/inflation and the realization that cosmic strings may be the only acceptable such defect. We find ourselves back in the business of trying to detect or limit and understand cosmic strings once again for the insight and constraints they put on p...

  9. Near InfraRed Imaging Spectrograph (NIRIS) for ground-based ...

    Indian Academy of Sciences (India)

    54

    NIRIS is a large field-of-view imaging spectrograph which is sensitive to fluctuation in ..... enhancement over low-latitudes has been shown to be developed as a ..... step forward towards passive remote sensing of the mesospheric dynamics.

  10. Cosmic Dawn with WFIRST

    Science.gov (United States)

    Rhoads, James

    Central objectives: WFIRST-AFTA has tremendous potential for studying the epoch of "Cosmic Dawn" the period encompassing the formation of the first galaxies and quasars, and their impact on the surrounding universe through cosmological reionization. Our goal is to ensure that this potential is realized through the middle stages of mission planning, culminating in designs for both WFIRST and its core surveys that meet the core objectives in dark energy and exoplanet science, while maximizing the complementary Cosmic Dawn science. Methods: We will consider a combined approach to studying Cosmic Dawn using a judicious mixture of guest investigator data analysis of the primary WFIRST surveys, and a specifically designed Guest Observer program to complement those surveys. The Guest Observer program will serve primarily to obtain deep field observations, with particular attention to the capabilities of WFIRST for spectroscopic deep fields using the WFI grism. We will bring to bear our years of experience with slitless spectroscopy on the Hubble Space Telescope, along with an expectation of JWST slitless grism spectroscopy. We will use this experience to examine the implications of WFIRST’s grism resolution and wavelength coverage for deep field observations, and if appropriate, to suggest potential modifications of these parameters to optimize the science return on WFIRST. We have assembled a team of experts specializing in (1) Lyman Break Galaxies at redshifts higher than 7 (2) Quasars at high redshifts (3) Lyman-alpha galaxies as probes of reionization (4) Theoretical simulations of high-redshift galaxies (5) Simulations of grism observations (6) post-processing analysis to find emission line galaxies and high redshift galaxies (7) JWST observations and calibrations. With this team we intend to do end-to-end simulations starting with halo populations and expected spectra of high redshift galaxies and finally extracting what we can learn about (a) reionization

  11. Studies in cosmic rays

    International Nuclear Information System (INIS)

    Bemalkhedkar, M.M.

    1974-03-01

    The investigation of the diurnal variation in the cosmic ray intensity on individual days has revealed a new class of diurnal variation showing a maximum around 09 hour direction in the interplanetary space. It is shown to occur during the recovery phase of Forbush decreases as well as during quiet periods. The rigidity spectrum of the anomalous diurnal variation has an exponent around zero, the same as that for the average diurnal variation exhibiting maximum around 18 hours in the interplanetary space. It is shown that the Forbush decreases associated with the diurnal variation exhibiting morning maximum, are 27 day recurrent in nature and are preceded by east limb solar flares on most of the occasions. A qualitative model of the transient modulation by solar corotating corpuscular streams of enhanced solar wind velocity, emanating from the active regions on the solar disc, is proposed to explain the anomalous diurnal anisotropy in the recovery phase of 27 day recurrent Forbush decreases. From this model, the cosmic ray diffusion coefficients, parallel and perpendicular to the interplanetary magnetic field inside the corotating stream, are derived and compared with the average values. To investigate the possibility of determining the energy spectra of cosmic ray intensity variations from a single station, a continuous record of neutron multiplicity spectrum has been obtained for the period October, 1967 - October, 1971, using the Gulmarg neutron monitor. The average multiplicity spectrum in the Gulmarg neutron monitor shows a mean multiplicity approximately equal to 1.4 for 12 Boron-tri-fluoride counters and is an increasing function of the number of counters used. The mean multiplicity measured in various other neutron monitors, when normalized to the cutoff rigidity of Gulmurg (11.91 GV), shows a systematic increase with the altitude of the station. (author)

  12. Cosmic baldness and stability

    Energy Technology Data Exchange (ETDEWEB)

    Panchapakesan, N.; Lohiya, D.

    1985-04-01

    The stability of the de Sitter metric and the relevance of the initial state of a domain which approaches a de Sitter universe asymptotically are investigated analytically, adapting the one-dimensional wave equation with effective potential derived by Khanal and Panchapakesan (1981), for the perturbations of the de Sitter-Schwarzschild metric, to the de Sitter case. It is demonstrated that initial nonspherical perturbations do not increase exponentially with time but rather decay, the frozen modes exponentially and the backscattered perturbations of finite angular momentum l as t to the -(2l - l). It is concluded that the cosmic horizon is stable and has no hair. 14 references.

  13. Cosmic strings and inflation

    International Nuclear Information System (INIS)

    Vishniac, E.T.

    1987-01-01

    We examine the compatibility of inflation with the cosmic string theory for galaxy formation. There is a general conflict between having sufficient string tension to effect galaxy formation, and reheating after inflation to a high enough temperature that strings may form in a thermal phase transition. To escape this conflict, we propose a class of models where the inflation is coupled to the string-producing field. The strings are formed late in inflation as the inflaton rolls towards its zero-temperature value. A large subset of these models have a novel large-scale distribution of galaxies that is fractal, displays biasing without dynamics or feedback mechanisms, and contains voids. (orig.)

  14. The cosmic microwave background

    International Nuclear Information System (INIS)

    Silk, J.

    1991-01-01

    Recent limits on spectral distortions and angular anisotropies in the cosmic microwave background are reviewed. The various backgrounds are described, and the theoretical implications are assessed. Constraints on inflationary cosmology dominated by cold dark matter (CDM) and on open cosmological models dominated by baryonic dark matter (BDM), with, respectively, primordial random phase scale-invariant curvature fluctuations or non-gaussian isocurvature fluctuations are described. More exotic theories are addressed, and I conclude with the 'bottom line': what theories expect experimentalists to be measuring within the next two to three years without having to abandon their most cherished theorists. (orig.)

  15. The Cosmic Background Explorer

    Science.gov (United States)

    Gulkis, Samuel; Lubin, Philip M.; Meyer, Stephan S.; Silverberg, Robert F.

    1990-01-01

    The Cosmic Background Explorer (CBE), NASA's cosmological satellite which will observe a radiative relic of the big bang, is discussed. The major questions connected to the big bang theory which may be clarified using the CBE are reviewed. The satellite instruments and experiments are described, including the Differential Microwave Radiometer, which measures the difference between microwave radiation emitted from two points on the sky, the Far-Infrared Absolute Spectrophotometer, which compares the spectrum of radiation from the sky at wavelengths from 100 microns to one cm with that from an internal blackbody, and the Diffuse Infrared Background Experiment, which searches for the radiation from the earliest generation of stars.

  16. Spectrum of cosmic fireballs

    Energy Technology Data Exchange (ETDEWEB)

    Cavallo, G [Consiglio Nazionale delle Ricerche, Bologna (Italy). Lab. TESRE; Horstman, H M [Bologna Univ. (Italy). Ist. di Astronomia

    1981-03-01

    A progress report on cosmic fireballs is presented. The main new results are: (a) the phenomenon should be almost universal, and most explosive ..gamma..-ray sources should show the characteristic fireball spectrum; (b) even if the radiation density is insufficient, pair production in electron-proton or electron-electron scattering might start the fireball; (c) some computed fireball spectra are shown. They all have in common a 1/E low-energy behaviour, a 100 keV flattening, and a approx.0.5 MeV cut-off.

  17. Tracing Cosmic Dawn

    Science.gov (United States)

    Fialkov, Anastasia

    2018-05-01

    Observational effort is on the way to probe the 21-cm of neutral hydrogen from the epochs of Reionization and Cosmic Dawn. Our current poor knowledge of high redshift astrophysics results in a large uncertainty in the theoretically predicted 21-cm signal. A recent parameter study that is highlighted here explores the variety of 21-cm signals resulting from viable astrophysical scenarios. Model-independent relations between the shape of the signal and the underlying astrophysics are discussed. Finally, I briefly note on possible alternative probes of the high redshift Universe, specifically Fast Radio Bursts.

  18. Comments on cosmic censorship

    International Nuclear Information System (INIS)

    Hawking, S.W.

    1979-01-01

    The cosmic censorship hypothesis and the closely related positive energy conjecture are the most important unsolved problems in classical general relativity. Roughly speaking the hypothesis is that nonsingular asymptotically flat initial data on a spacelike surface give rise to a solution in which any singularities that occur are not visible from infinity. Thus the solution near infinity would be unaffected by the breakdown of predictability associated with the singularities. A more precise formulation is given. The evidence for the censorship is mainly negative and this is discussed. The relationship of the hypothesis to quantum gravity and the quantum evaporation of black holes is also mentioned. (UK)

  19. Discovery of cosmic fractals

    CERN Document Server

    Baryshev, Yuri

    2002-01-01

    This is the first book to present the fascinating new results on the largest fractal structures in the universe. It guides the reader, in a simple way, to the frontiers of astronomy, explaining how fractals appear in cosmic physics, from our solar system to the megafractals in deep space. It also offers a personal view of the history of the idea of self-similarity and of cosmological principles, from Plato's ideal architecture of the heavens to Mandelbrot's fractals in the modern physical cosmos. In addition, this invaluable book presents the great fractal debate in astronomy (after Luciano Pi

  20. Theory Summary: Very High Energy Cosmic Rays

    Directory of Open Access Journals (Sweden)

    Sarkar Subir

    2013-06-01

    Full Text Available This is a summary of ISVHECRI 2012 from a theorist’s perspective. A hundred years after their discovery, there is renewed interest in very high energy cosmic raysand their interactions which can provide unique information on new physics well beyond the Standard Model if only we knew how to unambiguously decipher the experimental data. While the observational situation has improved dramatically on the past decade with regard to both improved statistics and better understood systematics, the long standing questions regarding the origin of cosmic rays remain only partially answered, while further questions have been raised by new data. A recent development discussed at this Symposium is the advent of forward physics data from several experiments at the LHC, which have broadly vindicated the air shower simulation Monte Carlos currently in use and reduced their uncertainties further. Nevertheless there is still a major extrapolation required to interpret the highest energy air showers observed which appear to be undergoing a puzzling change in their elemental composition, even casting doubt on whether the much vaunted GZK cutoff has indeedbeen observed. The situation is further compounded by the apparent disagreement between Auger and Telescope Array data. A crucial diagnostic will be provided by the detection of the accompanying ultra-high energy cosmic neutrinos — two intriguing events have recently been recorded by IceCube.

  1. Workshop for cascade project, physics using large acceptance spectrograph and its technical considerations

    International Nuclear Information System (INIS)

    1989-03-01

    The Workshop for Cascade, subtitled 'Physics Using Large Acceptance Spectrograph and Its Technical Considerations', was held on July 13, 1988 by the Nuclear Physics Research Center, Osaka University. The present proceedings carry a total of 18 reports, which are entitled 'RCNP Large Acceptance Spectrograph (plan)', 'Correlation Experiments with a System Consisting of a Small Number of Nucleons', 'Measurement of (d,d) and (d, 2 He) Reactions with Large Solid Angle Spectrograph', 'The (p,2p) and (p,pn) Reactions', 'Correlation Experiments with Large Acceptance Spectrograph', 'Efforts at Determination of Various Correlations in Alpha Particles', 'Two-Nucleon Correlation in Nucleus', 'A Study on Particle Migration Reaction with Broad-Band Spectrograph', 'Measurement of Response in Highly Excited State during Nucleon Migration Reaction', 'A Study on Δ-Excitation within Nucleus', 'A Few Problems Related with Response in Highly Excited State', 'Spin-Isospin Modes in Continuum', '(p,π) and (p,xπ) Reactions', 'Formation of π - in (p,2p) Reaction', 'Formation of π-Mesonic Atom with Consistent Momentum', 'Measurement of Excitation Functions by Means of 'Inconsistent' Dispersion in Magnetic Spectrograph', 'Deeply Bound π - States by 'π - Transfer' (n,p) Reactions', and 'On High Resolution (n,p) Facilities'. (N.K.)

  2. Cosmic ray electrons and protons, and their antiparticles

    International Nuclear Information System (INIS)

    Boezio, Mirko

    2014-01-01

    Cosmic rays are a sample of solar, galactic, and extragalactic matter. Their origin, acceleration mechanisms, and subsequent propagation toward Earth have intrigued scientists since their discovery. These issues can be studied via analysis of the energy spectra and composition of cosmic rays. Protons are the most abundant component of the cosmic radiation, and many experiments have been dedicated to the accurate measurement of their spectra. Complementary information is provided by electrons, which comprise about 1% of the cosmic radiation. Because of their low mass, electrons experience severe energy losses through synchrotron emission in the galactic magnetic field and inverse Compton scattering of radiation fields. Electrons therefore provide information on the local galactic environment that is not accessible from the study of the cosmic ray nuclei. Antiparticles, namely antiprotons and positrons, are produced in the interaction between cosmic ray nuclei and the interstellar matter. They are therefore intimately linked to the propagation mechanisms of the parent nuclei. Novel sources of primary cosmic ray antiparticles of either astrophysical (e.g., positrons from pulsars) or exotic origin (e.g., annihilation of dark matter particles) may exist. The nature of dark matter is one of the most prominent open questions in science today. An observation of positrons from pulsars would open a new observation window on these sources. Several experiments equipped with state-of-the art detector systems have recently presented results on the energy spectra of electrons, protons, and their antiparticles with a significant improvement in statistics and better control of systematics The status of the field will be reviewed, with a focus on these recent scientific results. (author)

  3. Reconstruction of cosmic and beam-halo muons with the CMS detector

    CERN Document Server

    Liu, Chang; Amapane, Nicola; Fernandez Bedoya, Cristina; Bellan, Riccardo; Biallass, Philipp; Bolognesi, Sara; Cerminara, Gianluca; Fouz Iglesias, Mary-Cruz; Giunta, Marina; Guiducci, Luigi; Hoepfner, Kerstin; Lacaprara, Stefano; Masetti, Gianni; Meneguzzo, Anna; Paolucci, Pierluigi; Puerta Pelayo, Jesus; Travaglini, Riccardo; Zanetti, Marco; Villanueva, Carlos

    2008-01-01

    The powerful muon and tracker systems of the CMS detector together with dedicated reconstruction software allow precise and efficient measurement of muon tracks originating from proton-proton collisions. The standard muon reconstruction algorithms, however, are inadequate to deal with muons that do not originate from collisions. This note discusses the design, implementation, and performance results of a dedicated cosmic muon track reconstruction algorithm, which features pattern recognition optimized for muons that are not coming from the interaction point, i.e., cosmic muons and beam-halo muons. To evaluate the performance of the new algorithm, data taken during Cosmic Challenge phases I and II were studied and compared with simulated cosmic data. In addition, a variety of more general topologies of cosmic muons and beam-halo muons were studied using simulated data to demonstrate some key features of the new algorithm.

  4. Ablation and chemical alteration of cosmic dust particles during entry into the earth`s atmosphere

    Digital Repository Service at National Institute of Oceanography (India)

    Rudraswami, N.G.; ShyamPrasad, M.; Dey, S.; Plane, J.M.C.; Feng, W.; Carrillo-Sanchez, J.D.; Fernandes, D.

    Most dust-sized cosmic particles undergo ablation and chemical alteration during atmospheric entry, which alters their original properties. A comprehensive understanding of this process is essential in order to decipher their pre...

  5. Cosmic Ballet or Devil's Mask?

    Science.gov (United States)

    2004-04-01

    Stars like our Sun are members of galaxies, and most galaxies are themselves members of clusters of galaxies. In these, they move around among each other in a mostly slow and graceful ballet. But every now and then, two or more of the members may get too close for comfort - the movements become hectic, sometimes indeed dramatic, as when galaxies end up colliding. ESO PR Photo 12/04 shows an example of such a cosmic tango. This is the superb triple system NGC 6769-71, located in the southern Pavo constellation (the Peacock) at a distance of 190 million light-years. This composite image was obtained on April 1, 2004, the day of the Fifth Anniversary of ESO's Very Large Telescope (VLT). It was taken in the imaging mode of the VIsible Multi-Object Spectrograph (VIMOS) on Melipal, one of the four 8.2-m Unit Telescopes of the VLT at the Paranal Observatory (Chile). The two upper galaxies, NGC 6769 (upper right) and NGC 6770 (upper left), are of equal brightness and size, while NGC 6771 (below) is about half as bright and slightly smaller. All three galaxies possess a central bulge of similar brightness. They consist of elderly, reddish stars and that of NGC 6771 is remarkable for its "boxy" shape, a rare occurrence among galaxies. Gravitational interaction in a small galaxy group NGC 6769 is a spiral galaxy with very tightly wound spiral arms, while NGC 6770 has two major spiral arms, one of which is rather straight and points towards the outer disc of NGC 6769. NGC 6770 is also peculiar in that it presents two comparatively straight dark lanes and a fainter arc that curves towards the third galaxy, NGC 6771 (below). It is also obvious from this new VLT photo that stars and gas have been stripped off NGC 6769 and NGC 6770, starting to form a common envelope around them, in the shape of a Devil's Mask. There is also a weak hint of a tenuous bridge between NGC 6769 and NGC 6771. All of these features testify to strong gravitational interaction between the three galaxies

  6. Phenomenology of cosmic phase transitions

    International Nuclear Information System (INIS)

    Kaempfer, B.; Lukacs, B.; Paal, G.

    1989-11-01

    The evolution of the cosmic matter from Planck temperature to the atomic combination temperature is considered from a phenomenological point of view. Particular emphasis is devoted to the sequence of cosmic phase transitions. The inflationary era at the temperature of the order of the grand unification energy scale and the quantum chromodynamic confinement transition are dealt with in detail. (author) 131 refs.; 26 figs

  7. Does a cosmic censor exist

    International Nuclear Information System (INIS)

    Israel, W.

    1984-01-01

    A distinction is drawn between the event horizon conjecture (EHC), the conjecture that an event horizon forms in a gravitational collapse, and cosmic censorship, the idea that every singularity which develops in the course of collapse must be enclosed within a horizon. It is argued that a body of circumstantial evidence seems to favor EHC, but cosmic censorship seems contraindicated

  8. Cosmic ray observations of Cygnus X-3: some theoretical implications

    International Nuclear Information System (INIS)

    Gaisser, T.K.; Halzen, F.

    1986-01-01

    We describe how the discovery of surface showers from Cygnus X-3 and other compact X-ray binaries may resolve the long-standing question of the origin of cosmic rays above 10 15 eV. In contrast, we show how possible underground muon observations raise rather than answer questions. 5 figs.; 17 refs

  9. Carl Sagan: Cosmic Evolution vs. the Creationist Myth.

    Science.gov (United States)

    Harnack, William J.

    1981-01-01

    Considers the dichotomy between the cosmic perspective and the creationist view. Presents an overview of various current explanations of the origin and nature of the universe, including scientific explanations, fundamentalist beliefs, and creation myths from other cultures. The article is based on comments made by Carl Sagan at the American…

  10. Large Scale Anomalies of the Cosmic Microwave Background with Planck

    DEFF Research Database (Denmark)

    Frejsel, Anne Mette

    This thesis focuses on the large scale anomalies of the Cosmic Microwave Background (CMB) and their possible origins. The investigations consist of two main parts. The first part is on statistical tests of the CMB, and the consistency of both maps and power spectrum. We find that the Planck data...

  11. About one of possible cosmic causes of extinction of organisms

    International Nuclear Information System (INIS)

    Kagramanov, Yu.R.

    2004-01-01

    Based on the analysis of diverse causes of extinction of organisms in the history of the Earth and a new hypothesis of cosmic origin of oil, a suggested new possible cause of such extinction is related to intoxication with hydrocarbons arriving from the outer space

  12. Superconducting cosmic string evolution of quasars

    International Nuclear Information System (INIS)

    Liu Yulin.

    1988-09-01

    The quasars may have been undergoing two evolutionary processes after they formed. As a result of the string loops shrinking at the first stage, the luminosities of the quasars increased gradually up to their maximum value at the redshift z ∼ 2, after then the second evolutionary stage began and the luminosity reduced. This result can be fitted by luminosity counting of quasars. Observable limit of quasars can be obtained naturally. Many phenomena, such as radiomorphology, density distribution between fuzz structure and broad line region and rotational curve may also originate from the first evolutionary stage of quasars as cosmic string. (author). 10 refs

  13. Science with Future Cosmic Microwave Background Observations

    Energy Technology Data Exchange (ETDEWEB)

    Bernardis, P. de; Calvo, M.; Giordano, C.; Masi, S.; Nati, F.; Piacentini, F.; Schillaci, A. [Dipartimento di Fisica, Universita di Roma La Sapienza, P.le A. Moro 2, 00185 Roma (Italy)

    2009-10-15

    After the successful measurements of many ground based, balloon-borne and satellite experiments, which started the era of 'Precision Cosmology', Cosmic Microwave Background (CMB) observations are now focusing on two targets: the precision measurement of B-modes in the polarization field, and the measurement of the Sunyaev-Zeldovich effect in distant clusters of galaxies. Polarization measurements represent the best way to probe the very early universe, and the energy scale of inflation. Fine-scale anisotropy measurements, possibly with spectral capabilities, can provide important information on dark matter and dark energy. Here we describe original approaches to these measurements.

  14. Science with Future Cosmic Microwave Background Observations

    International Nuclear Information System (INIS)

    Bernardis, P. de; Calvo, M.; Giordano, C.; Masi, S.; Nati, F.; Piacentini, F.; Schillaci, A.

    2009-01-01

    After the successful measurements of many ground based, balloon-borne and satellite experiments, which started the era of 'Precision Cosmology', Cosmic Microwave Background (CMB) observations are now focusing on two targets: the precision measurement of B-modes in the polarization field, and the measurement of the Sunyaev-Zeldovich effect in distant clusters of galaxies. Polarization measurements represent the best way to probe the very early universe, and the energy scale of inflation. Fine-scale anisotropy measurements, possibly with spectral capabilities, can provide important information on dark matter and dark energy. Here we describe original approaches to these measurements.

  15. George's cosmic treasure hunt

    CERN Document Server

    Hawking, Lucy; Parsons, Gary

    2009-01-01

    George and Annie explore the galaxy in this cosmic adventure from Stephen Hawking and Lucy Hawking, complete with essays from Professor Hawking about the latest in space travel. George is heartbroken when he learns that his friend Annie and her father are moving to the US. Eric has a new job working for the space program, looking for signs of life in the Universe. Eric leaves George with a gift—a book called The User’s Guide to the Universe. But Annie and Eric haven’t been gone for very long when Annie believes that she is being contacted by aliens, who have a terrible warning for her. George joins her in the US to help her with her quest—and before he knows it, he, Annie, Cosmos, and Annie’s annoying cousin Emmett have been swept up in a cosmic treasure hunt, spanning the whole galaxy and beyond. Lucy Hawking's own experiences in zero-gravity flight and interviews with astronauts at Cape Kennedy and the Johnson Space Center lend the book a sense of realism and excitement that is sure to fire up ima...

  16. L3 + Cosmics Experiment

    CERN Multimedia

    2002-01-01

    %RE4 %title\\\\ \\\\The L3+C experiment takes advantage of the unique properties of the L3 muon spectrometer to get an accurate measurement of cosmic ray muons 30 m underground. A new muon trigger, readout and DAQ system have been installed, as well as a scintillator array covering the upper surfaces of the L3 magnet for timing purposes. The acceptance amounts to 200 $m^2 sr$. The data are collected independently in parallel with L3 running. In spring 2000 a scintillator array will be installed on the roof of the SX hall in order to estimate the primary energy of air showers associated with events observed in L3+C.\\\\ \\\\The cosmic ray muon momentum spectrum, the zenith angular dependence and the charge ratio are measured with high accuracy between 20 and 2000 GeV/c. The results will provide new information about the primary composition, the shower development in the atmosphere, and the inclusive pion and kaon (production-) cross sections (specifically the "$\\pi$/K ratio") at high energies. These data will also hel...

  17. Cosmic rays and global warming

    Energy Technology Data Exchange (ETDEWEB)

    Erlykin, A.D. [P.N. Lebedev Physical Institute, Moscow (Russian Federation); Sloan, T. [Lancaster University (United Kingdom); Wolfendale, A.W. [Durham University (United Kingdom)

    2010-07-01

    The possible effects of cosmic rays on clouds could contribute to global warming. The argument is that the observed increased solar activity during the last century caused a decrease in the ionization due to cosmic rays since the lower energy cosmic particles are deflected by the magnetic field created by the increasing solar wind. This would lead to a decrease in cloud cover allowing more heating of the earth by the sun. Meteorological data combined to solar activity observations and simulations show that any effect of solar activity on clouds and the climate is likely to be through irradiance rather than cosmic rays. Since solar irradiance transfers 8 orders of magnitude more energy to the atmosphere than cosmic rays it is more plausible that this can produce a real effect. The total contribution of variable solar activity to global warming is shown to be less than 14% of the total temperature rise. (A.C.)

  18. From the solar system fo hidden cosmic structures

    Energy Technology Data Exchange (ETDEWEB)

    Benes, K

    1987-01-01

    The development of experimental astrophysics showed that in the evolution of planets, natural processes of a common nature take place. They include, e.g., radiogenic heat, the production of magmas, volcanic activity, degassing, etc. The solar system is a cosmic formation in an advanced stage of development and it is a realistic assumption that in the Galaxy other hidden planetary systems in various stages of development exist. The views on the possibility of the origination of life in other systems differ; life, however, is seen as a hidden property of cosmic matter. (M.D.).

  19. Cosmic magnetic fields

    CERN Document Server

    Kronberg, Philipp P

    2016-01-01

    Magnetic fields are important in the Universe and their effects contain the key to many astrophysical phenomena that are otherwise impossible to understand. This book presents an up-to-date overview of this fast-growing topic and its interconnections to plasma processes, astroparticle physics, high energy astrophysics, and cosmic evolution. The phenomenology and impact of magnetic fields are described in diverse astrophysical contexts within the Universe, from galaxies to the filaments and voids of the intergalactic medium, and out to the largest redshifts. The presentation of mathematical formulae is accessible and is designed to add insight into the broad range of topics discussed. Written for graduate students and researchers in astrophysics and related disciplines, this volume will inspire readers to devise new ways of thinking about magnetic fields in space on galaxy scales and beyond.

  20. Cosmic ray synergies

    CERN Multimedia

    Laëtitia Pedroso

    2010-01-01

    In laboratories, cosmic rays have been the subject of scientific research for many years. A more recent development is their appearance in schools, as educational tools. A recent workshop at CERN, organised by ASPERA in collaboration with EPPOG and EPPCN, had the goal of bringing together ideas and initiatives with a view to setting up a future common project.   Presentation at the workshop on 15 October. In research, as in education, you can sometimes get things done more rapidly and easily by joining forces. For roughly the past decade, physicists have been taking their particle detectors to secondary schools. “The challenge now is to bring all of these existing projects together in a network,” says Arnaud Marsollier, in charge of communication for the ASPERA network and organiser of the workshop. The workshop held on Friday, 15 October was attended by representatives of major European educational projects and members of the European Particle Physics Communication Network...

  1. Highest energy cosmic rays

    International Nuclear Information System (INIS)

    Nikolskij, S.

    1984-01-01

    Primary particles of cosmic radiation with highest energies cannot in view of their low intensity be recorded directly but for this purpose the phenomenon is used that these particles interact with nuclei in the atmosphere and give rise to what are known as extensive air showers. It was found that 40% of primary particles with an energy of 10 15 to 10 16 eV consist of protons, 12 to 15% of helium nuclei, 15% of iron nuclei, the rest of nuclei of other elements. Radiation intensity with an energy of 10 18 to 10 19 eV depends on the direction of incoming particles. Maximum intensity is in the direction of the centre of the nearest clustre of galaxies, minimal in the direction of the central area of our galaxy. (Ha)

  2. Overproduction of cosmic superstrings

    International Nuclear Information System (INIS)

    Barnaby, Neil; Berndsen, Aaron; Cline, James M.; Stoica, Horace

    2005-01-01

    We show that the naive application of the Kibble mechanism seriously underestimates the initial density of cosmic superstrings that can be formed during the annihilation of D-branes in the early universe, as in models of brane-antibrane inflation. We study the formation of defects in effective field theories of the string theory tachyon both analytically, by solving the equation of motion of the tachyon field near the core of the defect, and numerically, by evolving the tachyon field on a lattice. We find that defects generically form with correlation lengths of order M s -1 rather than H -1 . Hence, defects localized in extra dimensions may be formed at the end of inflation. This implies that brane-antibrane inflation models where inflation is driven by branes which wrap the compact manifold may have problems with overclosure by cosmological relics, such as domain walls and monopoles

  3. Our cosmic habitat

    CERN Document Server

    Rees, Martin

    2001-01-01

    Our universe seems strangely 'biophilic,' or hospitable to life. Is this providence or coincidence? According to Martin Rees, the answer depends on the answer to another question, the one posed by Einstein's famous remark: 'What interests me most is whether God could have made the world differently.' This highly engaging book centres on the fascinating consequences of the answer being 'yes'. Rees explores the notion that our universe is just part of a vast 'multiverse,' or ensemble of universes, in which most of the other universes are lifeless. What we call the laws of nature would then be local by laws, imposed in the aftermath of our own Big Bang. In this scenario, our cosmic habitat would be a special, possibly unique universe where the prevailing laws of physics allowed life to emerge.

  4. The Cosmic Microwave Background

    Directory of Open Access Journals (Sweden)

    Jones Aled

    1998-01-01

    Full Text Available We present a brief review of current theory and observations of the cosmic microwave background (CMB. New predictions for cosmological defect theories and an overview of the inflationary theory are discussed. Recent results from various observations of the anisotropies of the microwave background are described and a summary of the proposed experiments is presented. A new analysis technique based on Bayesian statistics that can be used to reconstruct the underlying sky fluctuations is summarised. Current CMB data is used to set some preliminary constraints on the values of fundamental cosmological parameters $Omega$ and $H_circ$ using the maximum likelihood technique. In addition, secondary anisotropies due to the Sunyaev-Zel'dovich effect are described.

  5. Cosmic Ray Antimatter

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    Over the last decade, space-born experiments have delivered new measurements of high energy cosmic-ray (CR) antiprotons and positrons, opening new frontiers in energy reach and precision. While being a promising discovery tool for new physics or exotic astrophysical phenomena, an irreducible background of antimatter comes from CR collisions with interstellar matter in the Galaxy. Understanding this irreducible source or constraining it from first principles is an interesting challenge: a game of hide-and-seek where the objective is to identify the laws of basic particle physics among the forest of astrophysical uncertainties. I describe an attempt to obtain such understanding, combining information from a zoo of CR species including massive nuclei and relativistic radioisotopes. I show that: (i) CR antiprotons most likely come from CR-gas collisions; (ii) positron data is consistent with, and suggestive of the same astrophysical production mechanism responsible for antiprotons and dominated by proton-proton c...

  6. Cosmic Magnetic Fields

    Science.gov (United States)

    Sánchez Almeida, J.; Martínez González, M. J.

    2018-05-01

    Magnetic fields play an important role in many astrophysical processes. They are difficult to detect and characterize since often their properties have to be inferred through interpreting the polarization of the light. Magnetic fields are also challenging to model and understand. Magnetized plasmas behave following highly non-linear differential equations having no general solution, so that every astrophysical problem represents a special case to be studied independently. Hence, magnetic fields are often an inconvenient subject which is overlooked or simply neglected (the elephant in the room, as they are dubbed in poster of the school). Such difficulty burdens the research on magnetic fields, which has evolved to become a very technical subject, with many small disconnected communities studying specific aspects and details. The school tried to amend the situation by providing a unifying view of the subject. The students had a chance to understand the behavior of magnetic fields in all astrophysical contexts, from cosmology to the Sun, and from starbursts to AGNs. The school was planed to present a balanced yet complete review of our knowledge, with excursions into the unknown to point out present and future lines of research. The subject of Cosmic Magnetic Fields was split into seven different topics: cosmic magnetic field essentials, solar magnetic fields, stellar magnetic fields, the role of magnetic fields on AGN feedback, magnetic fields in galaxies, magnetic fields in galaxy clusters and at larger scales, and primordial magnetic fields and magnetic fields in the early Universe. The corresponding lectures were delivered by seven well known and experienced scientists that have played key roles in the major advances of the field during the last years: F. Cattaneo, P. Judge, O. Kochukhov, R. Keppens, R. Beck, K. Dolag, and F. Finelli. Their lectures were recorded and are freely available at the IAC website: http://iactalks.iac.es/talks/serie/19.

  7. Test particle trajectories near cosmic strings

    Indian Academy of Sciences (India)

    We present a detailed analysis of the motion of test particle in the gravitational field of cosmic strings in different situations using the Hamilton–Jacobi (H–J) formalism. We have discussed the trajectories near static cosmic string, cosmic string in Brans–Dicke theory and cosmic string in dilaton gravity.

  8. Ultrahigh energy cosmic rays from nearby starburst galaxies

    Science.gov (United States)

    Attallah, Reda; Bouchachi, Dallel

    2018-04-01

    Ultrahigh energy cosmic rays are the most energetic of any subatomic particles ever observed in nature. The quest for their mysterious origin is currently a major scientific challenge. Here we explore the possibility that these particles originate from nearby starburst galaxies, a scenario that matches the recent observation by the Telescope Array experiment of a cosmic-ray hotspot above 57 EeV not far from the direction of the starburst galaxy M82. Specifically, we study the stochastic propagation in space of ultrahigh energy cosmic rays through the state-of-the-art simulation framework CRPropa 3, taking into account all relevant particle interactions as well as deflections by the intervening magnetic fields. To ensure a comprehensive understanding of this model, we consider the energy spectrum, the cosmogenic neutrinos and gamma rays, and the distribution of arrival directions. The starburst galaxy scenario reproduces well observations from both the Telescope Array and Pierre Auger Observatories, making it very attractive for explaining the origin of cosmic rays at the highest energies.

  9. Multitaper spectral analysis of cosmic rays Sao Martinho da Serra's muon telescope and Newark's neutron monitor data

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Marlos Rockenbach da; Alarcon, Walter Demetrio Gonzalez; Echer, Ezequiel; Lago, Alisson dal; Lucas, Aline de [National Institute for Space Research - INPE-MCT, Sao Jose dos Campos, SP (Brazil); Vieira, Luis Eduardo Antunes; Guarnieri, Fernando Luis [Universidade do Vale do Paraiba - UNIVAP, Sao Jose dos Campos, SP (Brazil); Schuch, Nelson Jorge [Southern Regional Space Research Center - CRSPE/INPE-MCT, Santa Maria, RS (Brazil); Munakata, Kazuoki, E-mail: marlos@dge.inpe.br, E-mail: gonzalez@dge.inpe.br, E-mail: eecher@dge.inpe.br, E-mail: dallago@dge.inpe.br, E-mail: delucas@dge.inpe.br, E-mail: levieira@univap.br, E-mail: guarnieri@univap.br, E-mail: njschuch@lacesm.ufsm.br, E-mail: kmuna00@gipac.shinshu-u.ac.jp [Physics Department, Shinshu University, Matsumoto (Japan)

    2007-07-01

    In this work we present an analysis on the correction efficiency of atmospheric effects on cosmic ray Sao Martinho da Serra's muon telescope and Newark's neutron monitor data. We use a Multitaper spectral analysis of cosmic rays time series to show the main periodicities present in the corrected and uncorrected data for the atmospheric effects. This kind of correction is very important when intends to study cosmic rays variations of extra-terrestrial origin. (author)

  10. A cosmic microwave background feature consistent with a cosmic texture.

    Science.gov (United States)

    Cruz, M; Turok, N; Vielva, P; Martínez-González, E; Hobson, M

    2007-12-07

    The Cosmic Microwave Background provides our most ancient image of the universe and our best tool for studying its early evolution. Theories of high-energy physics predict the formation of various types of topological defects in the very early universe, including cosmic texture, which would generate hot and cold spots in the Cosmic Microwave Background. We show through a Bayesian statistical analysis that the most prominent 5 degrees -radius cold spot observed in all-sky images, which is otherwise hard to explain, is compatible with having being caused by a texture. From this model, we constrain the fundamental symmetry-breaking energy scale to be (0) approximately 8.7 x 10(15) gigaelectron volts. If confirmed, this detection of a cosmic defect will probe physics at energies exceeding any conceivable terrestrial experiment.

  11. Cosmic rays, clouds and climate

    Energy Technology Data Exchange (ETDEWEB)

    Svensmark, Henrik [Danish Space Research Institute, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark)

    2007-07-01

    Changes in the intensity of galactic cosmic rays seems alter the Earth's cloudiness. A recent experiment has shown how electrons liberated by cosmic rays assist in making aerosols, the building blocks of cloud condensation nuclei, while anomalous climatic trends in Antarctica confirm the role of clouds in helping to drive climate change. Variations in the cosmic-ray influx due to solar magnetic activity account well for climatic fluctuations on decadal, centennial and millennial timescales. Over longer intervals, the changing galactic environment of the Solar System has had dramatic consequences, including Snowball Earth episodes.

  12. An estimate of cosmic dose component around Kudankulam site

    International Nuclear Information System (INIS)

    Vijayakumar, B.; Thomas, G.; Rajan, P.S.; Selvi, B.S.; Balamurugan, M.; Ravi, P.M.; Tripathi, R.M.

    2015-01-01

    Natural ionizing radiation pervades the whole environment and enters human lives in a wide variety of ways. It arises from natural processes such as the decay of terrestrially deposited radionuclides in the earth, and artificial processes like the use of X-rays in medicine. Thus, radiation can be classified as natural and artificial depending on its origin. Natural sources include cosmic rays, terrestrial gamma radiation, radon and its decay products in air and various radio nuclides found naturally in food and drink. Cosmic rays reach the earth from outer space. Artificial sources include medical X-rays, therapeutic use of radioisotopes, fallout from past weapon tests, discharges from nuclear industry, industrial gamma rays and use of radioisotopes in consumer products. This paper attempts to estimate the natural cosmic dose component around Kudankulam Nuclear Power Plant site in the south eastern coast of India. (author)

  13. Acceleration of galactic cosmic rays in shock waves

    International Nuclear Information System (INIS)

    Lagage, P.O.

    1981-06-01

    The old problem of the origin of cosmic rays has triggered off fresh interest owing to the discovery of a new model which enables a lot of energy to be transferred to a small number of particles on the one hand and the discovery of the coronal environment in which this transfer occurs, on the other. In this paper, interest is taken in the galactic cosmic rays and an endeavour is made to find out if the model can reveal the existence of cosmic rays over a wide energy range. The existence of an energy break, predicted by the model, was recognized fairly early but, in the literature, it varies from 30 GeV ro 10 6 GeV according to the authors. A study has been made of the two main causes of an energy break: the sphericity of the shock and the life time of the shock wave [fr

  14. Cosmic ray injection spectrum at the galactic sources

    Science.gov (United States)

    Lagutin, Anatoly; Tyumentsev, Alexander; Volkov, Nikolay

    The spectra of cosmic rays measured at Earth are different from their source spectra. A key to understanding this difference, being crucial for solving the problem of cosmic-ray origin, is the determination of how cosmic-ray (CR) particles propagate through the turbulent interstellar medium (ISM). If the medium is a quasi-homogeneous the propagation process can be described by a normal diffusion model. However, during a last few decades many evidences, both from theory and observations, of the existence of multiscale structures in the Galaxy have been found. Filaments, shells, clouds are entities widely spread in the ISM. In such a highly non-homogeneous (fractal-like) ISM the normal diffusion model certainly is not kept valid. Generalization of this model leads to what is known as "anomalous diffusion". The main goal of the report is to retrieve the cosmic ray injection spectrum at the galactic sources in the framework of the anomalous diffusion (AD) model. The anomaly in this model results from large free paths ("Levy flights") of particles between galactic inhomogeneities. In order to evaluate the CR spectrum at the sources, we carried out new calculation of the CR spectra at Earth. AD equation in terms of fractional derivatives have been used to describe CR propagation from the nearby (r≤1 kpc) young (t≤ 1 Myr) and multiple old distant (r > 1 kpc) sources. The assessment of the key model parameters have been based on the results of the particles diffusion in the cosmic and laboratory plasma. We show that in the framework of the anomalous diffusion model the locally observed basic features of the cosmic rays (difference between spectral exponents of proton, He and other nuclei, "knee" problem, positron to electron ratio) can be explained if the injection spectrum at the main galactic sources of cosmic rays has spectral exponent p˜ 2.85. The authors acknowledge support from The Russian Foundation for Basic Research grant No. 14-02-31524.

  15. The problem of scattering in fibre-fed VPH spectrographs and possible solutions

    Science.gov (United States)

    Ellis, S. C.; Saunders, Will; Betters, Chris; Croom, Scott

    2014-07-01

    All spectrographs unavoidably scatter light. Scattering in the spectral direction is problematic for sky subtraction, since atmospheric spectral lines are blurred. Scattering in the spatial direction is problematic for fibre fed spectrographs, since it limits how closely fibres can be packed together. We investigate the nature of this scattering and show that the scattering wings have both a Lorentzian component, and a shallower (1/r) component. We investigate the causes of this from a theoretical perspective, and argue that for the spectral PSF the Lorentzian wings are in part due to the profile of the illumination of the pupil of the spectrograph onto the diffraction grating, whereas the shallower component is from bulk scattering. We then investigate ways to mitigate the diffractive scattering by apodising the pupil. In the ideal case of a Gaussian apodised pupil, the scattering can be significantly improved. Finally we look at realistic models of the spectrograph pupils of fibre fed spectrographs with a centrally obstructed telescope, and show that it is possible to apodise the pupil through non-telecentric injection into the fibre.

  16. Interplanetary cosmic-ray scintillations

    Energy Technology Data Exchange (ETDEWEB)

    Toptygin, I N; Vasiliev, V N [Kalininskij Sel' skokhozyajstvennyj Inst. (USSR)

    1977-05-01

    The equation for the two-particles cosmic-ray distribution function is derived by means of the Boltzmann kinetic equation averaging. This equation is valid for arbitrary ratio of regular and random parts of the magnetic field. For small energy particles the guiding-center approximation is used. On the basis of the derived equation the dependence between power spectra of cosmic-ray intensity and random magnetic field is obtained. If power spectra are degree functions for high energy particles (approximately 10 GeV nucleon/sup -1/), then the spectral exponent ..gamma.. of magnetic field lies between rho and rho-2, where rho is the spectral exponent of cosmic-ray power spectra. The experimental data concerning moderate energy particles are in accordance with ..gamma..=rho, which demonstrates that the magnetic fluctuations are isotropic or cosmic-ray space gradient is small near the Earth orbit.

  17. The Energetic Trans-Iron Cosmic-ray Experiment (ENTICE)

    Science.gov (United States)

    Binns, W. R.; Adams. J. H.; Barghouty, A. F.; Christian, E. R.; Cummings, A. C.; Hams, T.; Israel, M. H.; Labrador, A. W.; Leske, R. A.; Link, J. T.; hide

    2009-01-01

    The ENTICE experiment is one of two instruments that comprise the "Orbiting Astrophysical Spectrometer in Space (OASIS)", which is presently undergoing a NASA "Astrophysics Strategic Mission Concept Study". ENTICE is designed to make high precision measurements of the abundances of individual elements from neon through the actinides and, in addition, will search for possible superheavy nuclei in the galactic cosmic rays. The ENTICE instrument utilizes silicon detectors, aerogel and acrylic Cherenkov counters, and a scintillating optical fiber hodoscope to measure the charge and energy of these ultra-heavy nuclei for energies greater than 0.5 GeV/nucleon. It is a large instrument consisting of four modules with a total effective geometrical factor of approx.20 sq m sr. Measurements made in space for a period of three years with ENTICE will enable us to determine if cosmic rays include a component of recently synthesized transuranic elements (Pu-94 and Cm-96), to measure the age of that component, and to test the model of the OB association origin of galactic cosmic rays. Additionally, these observations will enable us to study how diffusive shock acceleration of cosmic rays operates differently on interstellar grains and gas. Keywords: cosmic rays Galaxy:abundances

  18. Standard Cosmic Ray Energetics and Light Element Production

    CERN Document Server

    Fields, B D; Cassé, M; Vangioni-Flam, E; Fields, Brian D.; Olive, Keith A.; Casse, Michel; Vangioni-Flam, Elisabeth

    2001-01-01

    The recent observations of Be and B in metal poor stars has led to a reassessment of the origin of the light elements in the early Galaxy. At low it is metallicity ([O/H] < -1.75), it is necessary to introduce a production mechanism which is independent of the interstellar metallicity (primary). At higher metallicities, existing data might indicate that secondary production is dominant. In this paper, we focus on the secondary process, related to the standard Galactic cosmic rays, and we examine the cosmic ray energy requirements for both present and past epochs. We find the power input to maintain the present-day Galactic cosmic ray flux is about 1.5e41 erg/s = 5e50 erg/century. This implies that, if supernovae are the sites of cosmic ray acceleration, the fraction of explosion energy going to accelerated particles is about 30%, a value which we obtain consistently both from considering the present cosmic ray flux and confinement and from the present 9Be and 6Li abundances. Using the abundances of 9Be (an...

  19. Propagation of Galactic Cosmic Rays and Dark Matter indirect Detection

    International Nuclear Information System (INIS)

    Delahaye, Timur

    2010-07-01

    This thesis is dedicated to the study of propagation of cosmic electrons and positrons in the Milky Way and to the indirect detection of dark matter. The existence of dark matter is a hypothesis considered as reasonable from the point of view of cosmology, astrophysics and even particle physics. Nevertheless its detection still eludes us and it is not possible to verify this hypothesis by other means than gravitational one. A possible way to detect dark matter is to look for its annihilation or decay products among Galactic cosmic rays. During the last three years, data concerning cosmic ray electrons and positrons have been accumulated and have reached a remarkable precision. Such a precision requires from us to refine the theoretical models and to quantify the errors. This thesis addresses the study of all the sources of uncertainties affecting predictions of cosmic electrons and positron fluxes, primary and secondary, classical or from exotic origin. The greatest care has been dedicated to the sources and the propagation in the Galactic halo. Moreover a study of gamma and radio emissions associated to these cosmic rays is presented, again with the will of sizing uncertainties. Finally a status of the research for detection of annihilation or decay of Galactic dark matter is presented. (author)

  20. The Performance and Scientific Rationale for an Infrared Imaging Fourier Transform Spectrograph on a Large Space Telescope

    National Research Council Canada - National Science Library

    Graham, James R; Abrams, Mark; Bennett, C; Carr, J; Cook, K; Dey, A; Najita, J; Wishnow, E

    1998-01-01

    .... We consider the relationship between pixel size, spectral resolution, and diameter of the beam splitter for imaging and nonimaging Fourier transform spectrographs and give the condition required...

  1. Cosmic string induced CMB maps

    International Nuclear Information System (INIS)

    Landriau, M.; Shellard, E. P. S.

    2011-01-01

    We compute maps of CMB temperature fluctuations seeded by cosmic strings using high resolution simulations of cosmic strings in a Friedmann-Robertson-Walker universe. We create full-sky, 18 deg. and 3 deg. CMB maps, including the relevant string contribution at each resolution from before recombination to today. We extract the angular power spectrum from these maps, demonstrating the importance of recombination effects. We briefly discuss the probability density function of the pixel temperatures, their skewness, and kurtosis.

  2. Cosmic rays and Earth's climate

    DEFF Research Database (Denmark)

    Svensmark, Henrik

    2000-01-01

    During the last solar cycle the Earth's cloud cover underwent a modulation in phase with the cosmic ray flux. Assuming that there is a causal relationship between the two, it is expected and found that the Earth's temperature follows more closely decade variations in cosmic ray flux than other...... solar activity parameters. If the relationship is real the state of the Heliosphere affects the Earth's climate....

  3. Calculation of cosmic ray induced single event upsets: Program CRUP (Cosmic Ray Upset Program)

    Science.gov (United States)

    Shapiro, P.

    1983-09-01

    This report documents PROGRAM CRUP, COSMIC RAY UPSET PROGRAM. The computer program calculates cosmic ray induced single-event error rates in microelectronic circuits exposed to several representative cosmic-ray environments.

  4. A soft X-Ray flat field grating spectrograph and its experimental applications

    International Nuclear Information System (INIS)

    Ni Yuanlong; Mao Chusheng

    2001-01-01

    The principle, structure, and application results of a flat field grating spectrograph for X-ray laser research is presented. There are two kinds of the spectrograph. One uses a varied space grating with nominal line spacing 1200 l/mm, the spectral detection range is 5 - 50 nm, and another uses a 2400 l/mm varied line space grating, detection range is 1 - 10 nm. The experimental results of the former is introduced only. Both experimental results of this instrument using the soft X-ray film and a streak camera as the detecting elements are given. The spectral resolutions are 0.01 nm and 0.05 nm, respectively. The temporal resolution is 30 ps. Finally, the stigmatic structure of the spectrograph is introduced, which uses cylindrical mirror and spherical mirror as a focusing system. The magnification is 5, spatial resolution is 25 μm. The experimental results are given as well

  5. Proposal for the ion optics and for the kinematical fitting at the magnetic spectrograph BIG KARL

    International Nuclear Information System (INIS)

    Hinterberger, F.

    1986-01-01

    For the magnetic spectrograph BIG KARL the installation of an additional quadrupole lens is purposed. From this the possibility of a telescopic ion optic results. For future experiments a standard focusing with a spatial dispersion of 6.6 m and vanishing angular dispersion is proposed. The D/M ratio (dispersion/magnification) extends to 14.0 m, the maximal spatial angle lies at 3 msr. The energy range extends at a focal plane length of 0.66 m to 20%. For the kinematical fitting of the spectrograph the focal plane is shifted. This shift can be simply and rapidly realized for different K values by means of a software correction, if generally two spatial spectra in the focal plane are taken up. By this additionally for each event the actual scattering angle can be determined with relatively good resolution. The dispersion fit is completely decoupled from the kinematical fitting of the magnetic spectrograph. (orig.) [de

  6. X-ray spectrometer spectrograph telescope system. [for solar corona study

    Science.gov (United States)

    Bruner, E. C., Jr.; Acton, L. W.; Brown, W. A.; Salat, S. W.; Franks, A.; Schmidtke, G.; Schweizer, W.; Speer, R. J.

    1979-01-01

    A new sounding rocket payload that has been developed for X-ray spectroscopic studies of the solar corona is described. The instrument incorporates a grazing incidence Rowland mounted grating spectrograph and an extreme off-axis paraboloic sector feed system to isolate regions of the sun of order 1 x 10 arc seconds in size. The focal surface of the spectrograph is shared by photographic and photoelectric detection systems, with the latter serving as a part of the rocket pointing system control loop. Fabrication and alignment of the optical system is based on high precision machining and mechanical metrology techniques. The spectrograph has a resolution of 16 milliangstroms and modifications planned for future flights will improve the resolution to 5 milliangstroms, permitting line widths to be measured.

  7. Application of charge coupled devices as spatially-resolved detectors for X-ray spectrograph

    Energy Technology Data Exchange (ETDEWEB)

    Attelan-Langlet, S; Etlicher, B [Ecole Polytechnique, Palaiseau (France); Mishenskij, V O; Papazyan, Yu V; Smirnov, V P; Volkov, G S; Zajtsev, V I [Inst. for Thermonuclear and Innovation Investigations, Troitsk (Russian Federation)

    1997-12-31

    An X-ray crystal spectrograph which contains a CCD linear array as the position-sensitive detector is described. Radiation detection is performed directly onto CCD. The spectrograph has a limit of sensitivity at about 2 J/(A.ster), spectral resolution about 1000 and dynamic range 100-120. The device operates on-line with IBM-PC based control system. Software provides all data acquisition and treatment. Output spectra are presented in absolute units. The device was used during composite Z-pinch experiments at pulse-power installations ``Angara-5-1`` (TRINITI, Troitsk, Russia) and ``GAEL`` (Ecole Polytechnique, Palaiseau, France). Currently the spectrograph is included in the set of diagnostics of the ``Angara-5-1`` facility. Some of the spectra obtained are presented and discussed. (author). 4 figs., 9 refs.

  8. Life as a Cosmic Phenomenon: 2. the Panspermic Trajectory of Homo Sapiens

    Science.gov (United States)

    Tokoro, Gensuke; Wickramasinghe, N. Chandra

    We discuss the origin and evolution of Homo sapiens in a cosmic context, and in relation to the Hoyle-Wickramasinghe theory of panspermia for which there is now overwhelming evidence. It is argued that the first bacteria (archea) incident on the Earth via the agency of comets 3.8-4 billion years ago continued at later times to be augmented by viral genes (DNA, RNA) from space that eventually led to the evolutionary patterns we see in present-day biology. We argue that the current evolutionary status of Homo sapiens as well as its future trajectory is circumscribed by evolutionary processes that were pre-determined on a cosmic scale -- over vast distances and enormous spans of cosmic time. Based on this teleological hypothesis we postulate that two distinct classes of cosmic viruses (cosmic viral genes) are involved in accounting for the facts relating to the evolution of life.

  9. Comets - cosmic 'snowballs'

    International Nuclear Information System (INIS)

    Luest, R.

    1979-01-01

    Non-periodic comets come from regions at the limit of our solar system and have conserved their original structure and composition since they have originated from a pre-solar nebuly together with the sun and the planets about 4.5 x 10 9 years ago. They are icy bodies of kilometer size whose structure and chemical composition is of great interest also with respect to the origin of the solar system. It is hoped to send a space craft to comet Halley in 1986 to get more detailed informations. (orig.) [de

  10. Origins Space Telescope

    Science.gov (United States)

    Cooray, Asantha; Origins Space Telescope Study Team

    2018-01-01

    The Origins Space Telescope (OST) is the mission concept for the Far-Infrared Surveyor, a study in development by NASA in preparation for the 2020 Astronomy and Astrophysics Decadal Survey. Origins is planned to be a large aperture, actively-cooled telescope covering a wide span of the mid- to far-infrared spectrum. Its spectrographs will enable 3D surveys of the sky that will discover and characterize the most distant galaxies, Milky-Way, exoplanets, and the outer reaches of our Solar system. Origins will enable flagship-quality general observing programs led by the astronomical community in the 2030s. The Science and Technology Definition Team (STDT) would like to hear your science needs and ideas for this mission. The team can be contacted at firsurveyor_info@lists.ipac.caltech.edu. This presentation will provide a summary of the OST STDT, our completed first mission concept and an introduction to the second concept that will be studied at the study center in 2018. This presentation will also summarize key science drivers and the key study milestones between 2018 and 2020.

  11. Illustrated cosmic monopole

    CERN Document Server

    Seagrave, Wyken

    2015-01-01

    Truly bizarre, utterly unique I've never read a novel quite like this before. The author takes you on an exciting adventure full of unforgettable and vivid imagery. Solidly written with each character's personality shining through. If you find physics fascinating you will not be disappointed by the author's keen intellect and clear understanding of this most challenging (for me anyway) scientific subject. This is not a novel I will forget anytime soon, I would highly recommend it. Andrewly Very imaginative tale Anybody interested in a very imaginative and engrossing sci fi story needs to check this one out. I have been reading sci fi for decades and this story has elements that surprise me which is very unusual considering the number of novels and stories I have over the years. ric freeman Summary of the story The cosmic monopole has been wandering the Universe since it was created in the Big Bang. Its existence is fundamental to the way the Universe works. It is finally trapped by the powerful magnetic f...

  12. Performance testing of an off-plane reflection grating and silicon pore optic spectrograph at PANTER

    Science.gov (United States)

    Marlowe, Hannah; McEntaffer, Randall L.; Allured, Ryan; DeRoo, Casey T.; Donovan, Benjamin D.; Miles, Drew M.; Tutt, James H.; Burwitz, Vadim; Menz, Benedikt; Hartner, Gisela D.; Smith, Randall K.; Cheimets, Peter; Hertz, Edward; Bookbinder, Jay A.; Günther, Ramses; Yanson, Alex; Vacanti, Giuseppe; Ackermann, Marcelo

    2015-10-01

    An x-ray spectrograph consisting of aligned, radially ruled off-plane reflection gratings and silicon pore optics (SPO) was tested at the Max Planck Institute for Extraterrestrial Physics PANTER x-ray test facility. SPO is a test module for the proposed Arcus mission, which will also feature aligned off-plane reflection gratings. This test is the first time two off-plane gratings were actively aligned to each other and with an SPO to produce an overlapped spectrum. We report the performance of the complete spectrograph utilizing the aligned gratings module and plans for future development.

  13. Spectra of Th/Ar and U/Ne hollow cathode lamps for spectrograph calibration

    Science.gov (United States)

    Nave, Gillian; Shlosberg, Ariel; Kerber, Florian; Den Hartog, Elizabeth; Neureiter, Bianca

    2018-01-01

    Low-current Th/Ar hollow cathode lamps have long been used for calibration of astronomical spectrographs on ground-based telescopes. Thorium is an attractive element for calibration as it has a single isotope, has narrow spectral lines, and has a dense spectrum covering the whole of the visible region. However, the high density of the spectrum that makes it attractive for calibrating high-resolution spectrographs is a detriment for lower resolution spectrographs and this is not obvious by examination of existing linelists. In addition, recent changes in regulations regarding the handling of thorium have led to a degradation in the quality of Th/Ar calibration lamps, with contamination by molecular ThO lines that are strong enough to obscure the calibration lines of interest.We are pursuing two approaches to these problems. First, we have expanded and improved the NIST Standard Reference Database 161, "Spectrum of Th-Ar Hollow Cathode Lamps" to cover the region 272 nm to 5500 nm. Spectra of hollow cathode lamps at up to 3 different currents can now be displayed simultaneously. Interactive zooming and the ability to convolve any of the spectra with a Gaussian or uploaded instrument profile enable the user to see immediately what the spectrum would look like at the particular resolution of their spectrograph. Second, we have measured the spectrum of a recent, contaminated Th/Ar hollow cathode lamp using a high-resolution Echelle spectrograph (Madison Wisconsin) at a resolving power (R~ 250,000). This significantly exceeds the resolving power of most astronomical spectrographs and resolves many of the molecular lines of ThO. With these spectra we are measuring and calibrating the positions of these molecular lines in order to make them suitable for spectrograph calibration.In the near infrared region, U/Ne hollow cathode lamps give a higher density of calibration lines than Th/Ar lamps and will be implemented on the upgraded CRIRES+ spectrograph on ESO’s Very Large

  14. Observations of the radial velocity of the Sun as measured with the novel SONG spectrograph

    DEFF Research Database (Denmark)

    Pallé, P. L.; Grundahl, F.; Hage, A. Triviño

    2013-01-01

    Deployment of the prototype node of the SONG project took place in April 2012 at Observatorio del Teide (Canary Islands). Its key instrument (echelle spectrograph) was installed and operational a few weeks later while its 1 m feeding telescope suffered a considerable delay to meet the required...... specifications. Using a fibre-feed, solar light could be fed to the spectrograph and we carried out a 1-week observing campaign in June 2012 to evaluate its performance for measuring precision radial velocities. In this work we present the first results of this campaign by comparing the sensitivity of the SONG...

  15. The Oxford SWIFT Spectrograph: first commissioning and on-sky results

    OpenAIRE

    Thatte, Niranjan; Tecza, Mathias; Clarke, Fraser; Goodsall, Timothy; Fogarty, Lisa; Houghton, Ryan; Salter, Graeme; Scott, Nicholas; Davies, Roger L.; Bouchez, Antonin; Dekany, Richard

    2010-01-01

    The Oxford SWIFT spectrograph, an I & z band (6500-10500 A) integral field spectrograph, is designed to operate as a facility instrument at the 200 inch Hale Telescope on Palomar Mountain, in conjunction with the Palomar laser guide star adaptive optics system PALAO (and its upgrade to PALM3000). SWIFT provides spectra at R(≡λ/▵λ)~4000 of a contiguous two-dimensional field, 44 x 89 spatial pixels (spaxels) in size, at spatial scales of 0.235";, 0.16", and 0.08" per spaxel. It employs two 250μ...

  16. Spectrographic Determination of Trace Constituents in Rare Earths; Determinacion espectrografica de impurezas en tierras raras

    Energy Technology Data Exchange (ETDEWEB)

    Capdevila, C; Alvarez, F

    1962-07-01

    A spectrographic method was developed for the determination of 18 trace elements in lanthanum, cerium, praseodimium, neodimium and samarium compounds. The concentrations of the impurities cover the range of 0,5 to 500 ppm. Most of these impurities are determined by the carrier distillation method. Several more refractory elements have been determined by total burning of the sample with a direct current arc or by the conduction briquet excitation technique with a high voltage condensed spark. The work has been carried out with a Hilger Automatic Large Quartz Spectrograph. (Author) 5 refs.

  17. bHROS: A New High-Resolution Spectrograph Available on Gemini South

    Science.gov (United States)

    Margheim, S. J.; Gemini bHROS Team

    2005-12-01

    The Gemini bench-mounted High-Resolution Spectrograph (bHROS) is available for science programs beginning in 2006A. bHROS is the highest resolution (R=150,000) optical echelle spectrograph optimized for use on an 8-meter telescope. bHROS is fiber-fed via GMOS-S from the Gemini South focal plane and is available in both a dual-fiber Object/Sky mode and a single (larger) Object-only mode. Instrument characteristics and sample data taken during commissioning will be presented.

  18. Z-burst scenario for the highest energy cosmic rays

    International Nuclear Information System (INIS)

    Fodor, Z.

    2002-10-01

    The origin of highest energy cosmic rays is yet unknown. An appealing possibility is the so-called Z-burst scenario, in which a large fraction of these cosmic rays are decay products of Z bosons produced in the scattering of ultrahigh energy neutrinos on cosmological relic neutrinos. The comparison between the observed and predicted spectra constrains the mass of the heaviest neutrino. The required neutrino mass is fairly robust against variations of the presently unknown quantities, such as the amount of relic neutrino clustering, the universal photon radio background and the extragalactic magnetic field. Considering different possibilities for the ordinary cosmic rays the required neutrino masses are determined. In the most plausible case that the ordinary cosmic rays are of extragalactic origin and the universal radio background is strong enough to suppress high energy photons, the required neutrino mass is 0.08 eV ≤ m ν ≤ 0.40 eV. The required ultrahigh energy neutrino flux should be detected in the near future by experiments such as AMANDA, RICE or the Pierre Auger Observatory. (orig.)

  19. Pulsars as the sources of high energy cosmic ray positrons

    International Nuclear Information System (INIS)

    Hooper, Dan; Blasi, Pasquale; Serpico, Pasquale Dario

    2009-01-01

    Recent results from the PAMELA satellite indicate the presence of a large flux of positrons (relative to electrons) in the cosmic ray spectrum between approximately 10 and 100 GeV. As annihilating dark matter particles in many models are predicted to contribute to the cosmic ray positron spectrum in this energy range, a great deal of interest has resulted from this observation. Here, we consider pulsars (rapidly spinning, magnetized neutron stars) as an alternative source of this signal. After calculating the contribution to the cosmic ray positron and electron spectra from pulsars, we find that the spectrum observed by PAMELA could plausibly originate from such sources. In particular, a significant contribution is expected from the sum of all mature pulsars throughout the Milky Way, as well as from the most nearby mature pulsars (such as Geminga and B0656+14). The signal from nearby pulsars is expected to generate a small but significant dipole anisotropy in the cosmic ray electron spectrum, potentially providing a method by which the Fermi gamma-ray space telescope would be capable of discriminating between the pulsar and dark matter origins of the observed high energy positrons

  20. First cosmic-ray images of bone and soft tissue

    Science.gov (United States)

    Mrdja, Dusan; Bikit, Istvan; Bikit, Kristina; Slivka, Jaroslav; Hansman, Jan; Oláh, László; Varga, Dezső

    2016-11-01

    More than 120 years after Roentgen's first X-ray image, the first cosmic-ray muon images of bone and soft tissue are created. The pictures, shown in the present paper, represent the first radiographies of structures of organic origin ever recorded by cosmic rays. This result is achieved by a uniquely designed, simple and versatile cosmic-ray muon-imaging system, which consists of four plastic scintillation detectors and a muon tracker. This system does not use scattering or absorption of muons in order to deduct image information, but takes advantage of the production rate of secondaries in the target materials, detected in coincidence with muons. The 2D image slices of cow femur bone are obtained at several depths along the bone axis, together with the corresponding 3D image. Real organic soft tissue, polymethyl methacrylate and water, never seen before by any other muon imaging techniques, are also registered in the images. Thus, similar imaging systems, placed around structures of organic or inorganic origin, can be used for tomographic imaging using only the omnipresent cosmic radiation.

  1. Cosmic dust investigations. Pt. 2

    International Nuclear Information System (INIS)

    Simpson, J.A.; Tuzzolino, A.J.

    1989-01-01

    A series of experiments have been completed using accelerator dust particles in the mass range ≅ 10 -9 -10 -6 g and velocity range ≅ 2-12 km/s to measure the velocity loss and degree of fragmentation for dust particles penetrating 6 and 28 μm thick polyvinylidene fluoride (PVDF) dust detectors. These measurements prove that even for a ratio of PVDF foil thickness to particle diameter as large as 0.6, the velocity loss and fragmentation is far less than expected from earlier reports in the literature. For 6 μm thick foils the velocity loss is ≤5%. These experiments are based on an extension of our earlier work which showed that two PVDF foils spaced a given distance apart could provide accurate time-of-flight (TOF) information due to the fast pulse rise time of PVDF detector response. We also report on our present state of development of PVDF position-sensing detectors which identify the x, y coordinates of particle impact, using detector and electronic pulse techniques adapted from our semiconductor position-sensing cosmic-ray detectors. Typical position errors of ≅ 1 mm are readily achieved. Finally, we have combined the above developments into a dust-particle telescope which accurately (≅ 1 0 angular accuracy) measures the trajectory of the incident particle as well as its mass and incident velocity, irrespective of whether it is a charged or neutral particle. We discuss how this practical dust telescope can be combined with dust capture cells for space flight and later recovery for laboratory determination of elemental and isotopic composition of captured dust. We also describe a simpler trajectory array based on discrete mosaics of thin detectors which would measure trajectories with a mean angular error of ≅ 4 0 . We discuss the application of these instruments for distinguishing between interplanetary dust of cometary and asteroidal origin, and for measurements on a space station, from near-Earth trapped dust of artificial origin. (orig.)

  2. Looking for Cosmic Neutrino Background

    Directory of Open Access Journals (Sweden)

    Chiaki eYanagisawa

    2014-06-01

    Full Text Available Since the discovery of neutrino oscillation in atmospheric neutrinos by the Super-Kamiokande experiment in 1998, study of neutrinos has been one of exciting fields in high-energy physics. All the mixing angles were measured. Quests for 1 measurements of the remaining parameters, the lightest neutrino mass, the CP violating phase(s, and the sign of mass splitting between the mass eigenstates m3 and m1, and 2 better measurements to determine whether the mixing angle theta23 is less than pi/4, are in progress in a well-controlled manner. Determining the nature of neutrinos, whether they are Dirac or Majorana particles is also in progress with continuous improvement. On the other hand, although the ideas of detecting cosmic neutrino background have been discussed since 1960s, there has not been a serious concerted effort to achieve this goal. One of the reasons is that it is extremely difficult to detect such low energy neutrinos from the Big Bang. While there has been tremendous accumulation of information on Cosmic Microwave Background since its discovery in 1965, there is no direct evidence for Cosmic Neutrino Background. The importance of detecting Cosmic Neutrino Background is that, although detailed studies of Big Bang Nucleosynthesis and Cosmic Microwave Background give information of the early Universe at ~a few minutes old and ~300 k years old, respectively, observation of Cosmic Neutrino Background allows us to study the early Universe at $sim$ 1 sec old. This article reviews progress made in the past 50 years on detection methods of Cosmic Neutrino Background.

  3. Key scientific problems from Cosmic Ray History

    Science.gov (United States)

    Lev, Dorman

    2016-07-01

    young scientist from the Graz University, started to investigate how γ-radiations change their intensity with the distance from their sources, i.e. from the ground. When he performed his historical experiments on balloons in 1911-1912, it was found that at the beginning (up to approximately one km) ionization did not change, but with increase of the altitude for up to 4 - 5 km, the ionization rate escalates several times. Victor Hess drew a conclusion that some new unknown source of ionization of extra terrestrial origin exists. He named it 'high altitude radiation'. 5. Many scientists did not agree with this conclusion and tried to prove that the discovered new radiation has terrestrial origin (e.g., radium and other emanations from radioactive substances in the ground, particle acceleration up to high energies during thunderstorms, and so on). However, a lot of experiments showed that Victor Hess's findings are right: the discovered new radiation has extra terrestrial origin. 6. In 1926 the great American scientist Robert Millikan named them 'cosmic rays': cosmic as coming from space, and rays because it was generally wrongly accepted at those time that the new radiation mostly consisted of γ-rays. Robert Millikan believed that God exists and continues to work: in space God has creates He atoms from four atoms of H with the generation high energy gamma rays (in contradiction with physical laws, as this reaction can occur only at very high temperature and great density, e.g., as inside stars). 7. On this problem, interesting to many people, there was a famous public discussion between two Nobel laureates Arthur Compton and Robert Millikan, widely reported in newspapers. Only after a lot of latitude surveys in the 1930s, organized mostly by Compton and Millikan, it became clear that 'cosmic rays' are mostly not γ-rays, but rather charged particles (based on Störmer's theory about behavior of charged energetic particles in the geomagnetic field, developed in 1910

  4. Original Researc Original Research

    African Journals Online (AJOL)

    RAGHAVENDRA

    Practices. Problems. Supervision. Primary School. *Corresponding Author: Asrat Dagnew. E-mail: asratboza@yahoo.com tructional support. The relevant and ... vision is one of indispensable system pment. Supervision is a system of that directly concerned on the aff members in a school or other. Original Research ...

  5. Original Research Original Research

    African Journals Online (AJOL)

    RAGHAVENDRA

    language in social interaction( Anto et al., 2012; Tessema et al., 2012). While such ..... 10 items on a five-point Likert scale originally developed by Benard et al. (2007). ..... self-confidence, and hold down their anxiety levels. In this study ...

  6. Nearest Cosmic Mirage

    Science.gov (United States)

    2003-07-01

    Discovery of quadruply lensed quasar with Einstein ring Summary Using the ESO 3.6-m telescope at La Silla (Chile), an international team of astronomers [1] has discovered a complex cosmic mirage in the southern constellation Crater (The Cup). This "gravitational lens" system consists of (at least) four images of the same quasar as well as a ring-shaped image of the galaxy in which the quasar resides - known as an "Einstein ring". The more nearby lensing galaxy that causes this intriguing optical illusion is also well visible. The team obtained spectra of these objects with the new EMMI camera mounted on the ESO 3.5-m New Technology Telescope (NTT), also at the La Silla observatory. They find that the lensed quasar [2] is located at a distance of 6,300 million light-years (its "redshift" is z = 0.66 [3]) while the lensing elliptical galaxy is rougly halfway between the quasar and us, at a distance of 3,500 million light-years (z = 0.3). The system has been designated RXS J1131-1231 - it is the closest gravitationally lensed quasar discovered so far . PR Photo 20a/03 : Image of the gravitational lens system RXS J1131-1231 (ESO 3.6m Telescope). PR Photo 20b/03 : Spectra of two lensed images of the source quasar and the lensing galaxy. Cosmic mirages The physical principle behind a "gravitational lens" (also known as a "cosmic mirage") has been known since 1916 as a consequence of Albert Einstein's Theory of General Relativity . The gravitational field of a massive object curves the local geometry of the Universe, so light rays passing close to the object are bent (like a "straight line" on the surface of the Earth is necessarily curved because of the curvature of the Earth's surface). This effect was first observed by astronomers in 1919 during a total solar eclipse. Accurate positional measurements of stars seen in the dark sky near the eclipsed Sun indicated an apparent displacement in the direction opposite to the Sun, about as much as predicted by Einstein

  7. The cosmic spiderweb: equivalence of cosmic, architectural and origami tessellations

    Science.gov (United States)

    Neyrinck, Mark C.; Hidding, Johan; Konstantatou, Marina; van de Weygaert, Rien

    2018-04-01

    For over 20 years, the term `cosmic web' has guided our understanding of the large-scale arrangement of matter in the cosmos, accurately evoking the concept of a network of galaxies linked by filaments. But the physical correspondence between the cosmic web and structural engineering or textile `spiderwebs' is even deeper than previously known, and also extends to origami tessellations. Here, we explain that in a good structure-formation approximation known as the adhesion model, threads of the cosmic web form a spiderweb, i.e. can be strung up to be entirely in tension. The correspondence is exact if nodes sampling voids are included, and if structure is excluded within collapsed regions (walls, filaments and haloes), where dark-matter multistreaming and baryonic physics affect the structure. We also suggest how concepts arising from this link might be used to test cosmological models: for example, to test for large-scale anisotropy and rotational flows in the cosmos.

  8. The cosmic spiderweb: equivalence of cosmic, architectural and origami tessellations.

    Science.gov (United States)

    Neyrinck, Mark C; Hidding, Johan; Konstantatou, Marina; van de Weygaert, Rien

    2018-04-01

    For over 20 years, the term 'cosmic web' has guided our understanding of the large-scale arrangement of matter in the cosmos, accurately evoking the concept of a network of galaxies linked by filaments. But the physical correspondence between the cosmic web and structural engineering or textile 'spiderwebs' is even deeper than previously known, and also extends to origami tessellations. Here, we explain that in a good structure-formation approximation known as the adhesion model, threads of the cosmic web form a spiderweb, i.e. can be strung up to be entirely in tension. The correspondence is exact if nodes sampling voids are included, and if structure is excluded within collapsed regions (walls, filaments and haloes), where dark-matter multistreaming and baryonic physics affect the structure. We also suggest how concepts arising from this link might be used to test cosmological models: for example, to test for large-scale anisotropy and rotational flows in the cosmos.

  9. Fitting cosmic microwave background data with cosmic strings and inflation.

    Science.gov (United States)

    Bevis, Neil; Hindmarsh, Mark; Kunz, Martin; Urrestilla, Jon

    2008-01-18

    We perform a multiparameter likelihood analysis to compare measurements of the cosmic microwave background (CMB) power spectra with predictions from models involving cosmic strings. Adding strings to the standard case of a primordial spectrum with power-law tilt ns, we find a 2sigma detection of strings: f10=0.11+/-0.05, where f10 is the fractional contribution made by strings in the temperature power spectrum (at l=10). CMB data give moderate preference to the model ns=1 with cosmic strings over the standard zero-strings model with variable tilt. When additional non-CMB data are incorporated, the two models become on a par. With variable ns and these extra data, we find that f10<0.11, which corresponds to Gmicro<0.7x10(-6) (where micro is the string tension and G is the gravitational constant).

  10. Robust constraint on cosmic textures from the cosmic microwave background.

    Science.gov (United States)

    Feeney, Stephen M; Johnson, Matthew C; Mortlock, Daniel J; Peiris, Hiranya V

    2012-06-15

    Fluctuations in the cosmic microwave background (CMB) contain information which has been pivotal in establishing the current cosmological model. These data can also be used to test well-motivated additions to this model, such as cosmic textures. Textures are a type of topological defect that can be produced during a cosmological phase transition in the early Universe, and which leave characteristic hot and cold spots in the CMB. We apply bayesian methods to carry out a rigorous test of the texture hypothesis, using full-sky data from the Wilkinson Microwave Anisotropy Probe. We conclude that current data do not warrant augmenting the standard cosmological model with textures. We rule out at 95% confidence models that predict more than 6 detectable cosmic textures on the full sky.

  11. Constraining sources of ultrahigh energy cosmic rays and shear acceleration mechanism of particles in relativistic jets

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ruoyu

    2015-06-10

    Ultrahigh energy cosmic rays are extreme energetic particles from outer space. They have aroused great interest among scientists for more than fifty years. However, due to the rarity of the events and complexity of the process of their propagation to Earth, they are still one of the biggest puzzles in modern high energy astrophysics. This dissertation is dedicated to study the origin of ultrahigh energy cosmic rays from various aspects. Firstly, we discuss a possible link between recently discovered sub-PeV/PeV neutrinos and ultrahigh energy cosmic rays. If these two kinds of particles share the same origin, the observation of neutrinos may provide additional and non-trivial constraints on the sources of ultrahigh energy cosmic rays. Secondly, we jointly employ the chemical composition measurement and the arrival directions of ultrahigh energy cosmic rays, and find a robust upper limit for distances of sources of ultrahigh energy cosmic rays above ∝55 EeV, as well as a lower limit for their metallicities. Finally, we study the shear acceleration mechanism in relativistic jets, which is a more efficient mechanism for the acceleration of higher energy particle. We compute the acceleration efficiency and the time-dependent particle energy spectrum, and explore the feature of synchrotron radiation of the accelerated particles. The possible realizations of this mechanism for acceleration of ultrahigh energy cosmic rays in different astrophysical environments is also discussed.

  12. Project overview of OPTIMOS-EVE: the fibre-fed multi-object spectrograph for the E-ELT

    NARCIS (Netherlands)

    Navarro, R.; Chemla, F.; Bonifacio, P.; Flores, H.; Guinouard, I.; Huet, J.-M.; Puech, M.; Royer, F.; Pragt, J.H.; Wulterkens, G.; Sawyer, E.C.; Caldwell, M.E.; Tosh, I.A.J.; Whalley, M.S.; Woodhouse, G.F.W.; Spanò, P.; Di Marcantonio, P.; Andersen, M.I.; Dalton, G.B.; Kaper, L.; Hammer, F.

    2010-01-01

    OPTIMOS-EVE (OPTical Infrared Multi Object Spectrograph - Extreme Visual Explorer) is the fibre fed multi object spectrograph proposed for the European Extremely Large Telescope (E-ELT), planned to be operational in 2018 at Cerro Armazones (Chile). It is designed to provide a spectral resolution of

  13. Effect of Acoustic Spectrographic Instruction on Production of English /i/ and /I/ by Spanish Pre-Service English Teachers

    Science.gov (United States)

    Quintana-Lara, Marcela

    2014-01-01

    This study investigates the effects of Acoustic Spectrographic Instruction on the production of the English phonological contrast /i/ and / I /. Acoustic Spectrographic Instruction is based on the assumption that physical representations of speech sounds and spectrography allow learners to objectively see and modify those non-accurate features in…

  14. The Coude spectrograph and echelle scanner of the 2.7 m telescope at McDonald observatory

    Science.gov (United States)

    Tull, R. G.

    1972-01-01

    The design of the Coude spectrograph of the 2.7 m McDonald telescope is discussed. A description is given of the Coude scanner which uses the spectrograph optics, the configuration of the large echelle and the computer scanner control and data systems.

  15. Measurements of the cosmic background radiation

    International Nuclear Information System (INIS)

    Weiss, R.

    1980-01-01

    Measurements of the attributes of the 2.7-K microwave background radiation (CBR) are reviewed, with emphasis on the analytic phase of CBR studies. Methods for the direct measurement of the CBR spectrum are discussed. Attention is given to receivers, antennas, absolute receiver calibration, atmospheric emission and absorption, the galactic background contribution, the analysis of LF measurements, and recent HF observations of the CBR spectrum. Measurements of the large-angular-scale intensity distribution of the CBR (the most convincing evidence that the radiation is of cosmological origin) are examined, along with limits on the linear polarization of the CBR. A description is given of the NASA-sponsored Cosmic Background Explorer (COBE) satellite mission. The results of the COBE mission will be a set of sky maps showing, in the wave number range from 1 to 10,000 kaysers, the galactic background radiation due to synchrotron emission from galactic cosmic rays, to diffuse thermal emission from H II regions, and to diffuse thermal emission from interstellar and interplanetary dust, as well as a residue consisting of the CBR and whatever other cosmological background might exist

  16. Dosimetry for occupational exposure to cosmic radiation

    International Nuclear Information System (INIS)

    Bartlett, D.T.; McAulay, I.R.; Schrewe, U.J.

    1997-01-01

    Aircraft crew and frequent flyers are exposed to elevated levels of cosmic radiation of galactic and solar origin and secondary radiation produced in the atmosphere, aircraft structure, etc. This has been recognised for some time and estimates of the exposure of aircraft crew have been made previously and included in, for example, UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation) publications. The recent increased interest has been brought about by several factors - the consideration that the relative biological effectiveness of the neutron component was being underestimated; the trend towards higher cruising altitudes for subsonic commercial aircraft and business jet aircraft; and most importantly, the recommendations of the International Commission on Radiological Protection (ICRP) in Publication 60, and the revision of the Euratom Basic Safety Standards Directive (BSS). In 1992, the European Dosimetry Group (EURADOS) established a Working Group to consider the exposure to cosmic radiation of aircraft crew, and the scientific and technical problems associated with radiation protection dosimetry for this occupational group. The Working Group was composed of fifteen scientists (plus a corresponding member) involved in this field of study and with knowledge of radiation measurement at aviation altitudes. This paper is based on the findings of this Working Group. (author)

  17. Cosmic logic: a computational model

    International Nuclear Information System (INIS)

    Vanchurin, Vitaly

    2016-01-01

    We initiate a formal study of logical inferences in context of the measure problem in cosmology or what we call cosmic logic. We describe a simple computational model of cosmic logic suitable for analysis of, for example, discretized cosmological systems. The construction is based on a particular model of computation, developed by Alan Turing, with cosmic observers (CO), cosmic measures (CM) and cosmic symmetries (CS) described by Turing machines. CO machines always start with a blank tape and CM machines take CO's Turing number (also known as description number or Gödel number) as input and output the corresponding probability. Similarly, CS machines take CO's Turing number as input, but output either one if the CO machines are in the same equivalence class or zero otherwise. We argue that CS machines are more fundamental than CM machines and, thus, should be used as building blocks in constructing CM machines. We prove the non-computability of a CS machine which discriminates between two classes of CO machines: mortal that halts in finite time and immortal that runs forever. In context of eternal inflation this result implies that it is impossible to construct CM machines to compute probabilities on the set of all CO machines using cut-off prescriptions. The cut-off measures can still be used if the set is reduced to include only machines which halt after a finite and predetermined number of steps

  18. Cosmic PeV neutrinos and the sources of ultrahigh energy protons

    Science.gov (United States)

    Kistler, Matthew D.; Stanev, Todor; Yüksel, Hasan

    2014-12-01

    The IceCube experiment recently detected the first flux of high-energy neutrinos in excess of atmospheric backgrounds. We examine whether these neutrinos originate from within the same extragalactic sources as ultrahigh energy cosmic rays. Starting from rather general assumptions about spectra and flavors, we find that producing a neutrino flux at the requisite level through pion photoproduction leads to a flux of protons well below the cosmic-ray data at ˜1 018 eV , where the composition is light, unless pions/muons cool before decaying. This suggests a dominant class of accelerator that allows for cosmic rays to escape without significant neutrino yields.

  19. Infra-red photon release from cosmic dust entering into the earth's atmosphere

    International Nuclear Information System (INIS)

    Kobayashi, Koichi

    1975-01-01

    Cosmic dust brings considerably high intensity of energy flux to the upper atmosphere of the earth. Most of this energy can be converted to infra-red radiation. It can be concluded that the infra-red background radiation in the sky of its wavelength of less than about 10μ may considerably originate in the cosmic dust which has entered the earth's atmosphere, or that the upper limit to the flux of cosmic dust is about 10 5 tons/earth year. (author)

  20. Evaluation of spectrographic standards for the carrier-distillation analysis of PuO2

    International Nuclear Information System (INIS)

    Martell, C.J.; Myers, W.M.

    1976-05-01

    Three plutonium metals whose impurity contents have been accurately determined are used to evaluate spectrographic standards. Best results are obtained when (1) highly impure samples are diluted, (2) the internal standard, cobalt, is used, (3) a linear curve is fitted to the standard data that bracket the impurity concentration, and (4) plutonium standards containing 22 impurities are used

  1. Improvement of spectrographic analyses by the use of a mechanical packer in the arc distillation technique

    International Nuclear Information System (INIS)

    Buffereau, M.; Deniaud, S.; Pichotin, B.; Violet, R.

    1965-01-01

    One studies improvement of spectrographic analysis by the 'carrier distillation' method with the help of a mechanical device. Experiments and advantages of such an apparatus are given (precision and reproducibility improvement, operator factor suppression). A routine apparatus (French patent no 976.493) is described. (authors) [fr

  2. Performances of X-shooter, the new wide-band intermediate resolution spectrograph at the VLT

    NARCIS (Netherlands)

    Vernet, J.; Dekker, H.; D'Odorico, S.; Mason, E.; Di Marcantonio, P.; Downing, M.; Elswijk, E.; Finger, G.; Fischer, G.; Kerber, F.; Kern, L.; Lizon, J.-L.; Lucuix, C.; Mainieri, V.; Modigliani, A.; Patat, F.; Ramsay, S.; Santin, P.; Vidali, M.; Groot, P.; Guinouard, I.; Hammer, F.; Kaper, L.; Kjærgaard-Rasmussen, P.; Navarro, R.; Randich, S.; Zerbi, F.

    2010-01-01

    X-shooter is the first second-generation instrument newly commissioned a the VLT. It is a high efficiency single target intermediate resolution spectrograph covering the range 300 - 2500 nm in a single shot. We summarize the main characteristics of the instrument and present its performances as

  3. X-shooter, the new wide band intermediate resolution spectrograph at the ESO Very Large Telescope

    NARCIS (Netherlands)

    Vernet, J.; Dekker, H.; D'Odorico, S.; Kaper, L.; Kjaergaard, P.; Hammer, F.; Randich, S.; Zerbi, F.; Groot, P.J.; Hjorth, J.; Guinouard, I.; Navarro, R.; Adolfse, T.; Albers, P.W.; Amans, J.-P.; Andersen, J.J.; Andersen, M.I.; Binetruy, P.; Bristow, P.; Castillo, R.; Chemla, F.; Christensen, L.; Conconi, P.; Conzelmann, R.; Dam, J.; De Caprio, V.; de Ugarte Postigo, A.; Delabre, B.; Di Marcantonio, P.; Downing, M.; Elswijk, E.; Finger, G.; Fischer, G.; Flores, H.; François, P.; Goldoni, P.; Guglielmi, L.; Haigron, R.; Hanenburg, H.; Hendriks, I.; Horrobin, M.; Horville, D.; Jessen, N.C.; Kerber, F.; Kern, L.; Kiekebusch, M.; Kleszcz, P.; Klougart, J.; Kragt, J.; Larsen, H.H.; Lizon, J.-L.; Lucuix, C.; Mainieri, V.; Manuputy, R.; Martayan, C.; Mason, E.; Mazzoleni, R.; Michaelsen, N.; Modigliani, A.; Moehler, S.; Møller, P.; Norup Sørensen, A.; Nørregaard, P.; Péroux, C.; Patat, F.; Pena, E.; Pragt, J.; Reinero, C.; Rigal, F.; Riva, M.; Roelfsema, R.; Royer, F.; Sacco, G.; Santin, P.; Schoenmaker, T.; Spano, P.; Sweers, E.; ter Horst, R.; Tintori, M.; Tromp, N.; van Dael, P.; van Vliet, H.; Venema, L.; Vidali, M.; Vinther, J.; Vola, P.; Winters, R.; Wistisen, D.; Wulterkens, G.; Zacchei, A.

    2011-01-01

    X-shooter is the first 2nd generation instrument of the ESO Very Large Telescope (VLT). It is a very efficient, single-target, intermediate-resolution spectrograph that was installed at the Cassegrain focus of UT2 in 2009. The instrument covers, in a single exposure, the spectral range from 300 to

  4. X-shooter, the new wide band intermediate resolution spectrograph at the ESO Very Large Telescope

    DEFF Research Database (Denmark)

    Vernet, J.; Dekker, H.; D'Odorico, S.

    2011-01-01

    X-shooter is the first 2nd generation instrument of the ESO Very Large Telescope (VLT). It is a very efficient, single-target, intermediate-resolution spectrograph that was installed at the Cassegrain focus of UT2 in 2009. The instrument covers, in a single exposure, the spectral range from 300 t...

  5. Quantitative imaging through a spectrograph : 2. stoichiometry mapping by Raman scattering

    NARCIS (Netherlands)

    Tolboom, R.A.L.; Dam, N.J.; Meulen, ter J.J.

    2004-01-01

    The Bayesian deconvolution algorithm described in a preceding paper [Appl. Opt. 43, 5669–5681 (2004)] is applied to measurement of the two-dimensional stoichiometry field in a combustible methane-air mixture by Raman imaging through a spectrograph. Stoichiometry (fuel equivalence ratio) is derived

  6. Quantitative imaging through a spectrograph. 2. Stoichiometry mapping by Raman scattering.

    NARCIS (Netherlands)

    Tolboom, R.A.L.; Dam, N.J.; Meulen, J.J. ter

    2004-01-01

    The Bayesian deconvolution algorithm described in a preceding paper [Appl. Opt. 43, 5669-5681 (2004)] is applied to measurement of the two-dimensional stoichiometry field in a combustible methane-air mixture by Raman imaging through a spectrograph. Stoichiometry (fuel equivalence ratio) is derived

  7. MOONS: a multi-object optical and near-infrared spectrograph for the VLT

    NARCIS (Netherlands)

    Cirasuolo, M.; Afonso, J.; Bender, R.; Bonifacio, P.; Evans, C.; Kaper, L.; Oliva, Ernesto; Vanzi, Leonardo; Abreu, Manuel; Atad-Ettedgui, Eli; Babusiaux, Carine; Bauer, Franz E.; Best, Philip; Bezawada, Naidu; Bryson, Ian R.; Cabral, Alexandre; Caputi, Karina; Centrone, Mauro; Chemla, Fanny; Cimatti, Andrea; Cioni, Maria-Rosa; Clementini, Gisella; Coelho, João.; Daddi, Emanuele; Dunlop, James S.; Feltzing, Sofia; Ferguson, Annette; Flores, Hector; Fontana, Adriano; Fynbo, Johan; Garilli, Bianca; Glauser, Adrian M.; Guinouard, Isabelle; Hammer, Jean-François; Hastings, Peter R.; Hess, Hans-Joachim; Ivison, Rob J.; Jagourel, Pascal; Jarvis, Matt; Kauffman, G.; Lawrence, A.; Lee, D.; Li Causi, G.; Lilly, S.; Lorenzetti, D.; Maiolino, R.; Mannucci, F.; McLure, R.; Minniti, D.; Montgomery, D.; Muschielok, B.; Nandra, K.; Navarro, R.; Norberg, P.; Origlia, L.; Padilla, N.; Peacock, J.; Pedicini, F.; Pentericci, L.; Pragt, J.; Puech, M.; Randich, S.; Renzini, A.; Ryde, N.; Rodrigues, M.; Royer, F.; Saglia, R.; Sánchez, A.; Schnetler, H.; Sobral, D.; Speziali, R.; Todd, S.; Tolstoy, E.; Torres, M.; Venema, L.; Vitali, F.; Wegner, M.; Wells, M.; Wild, V.; Wright, G.

    MOONS is a new conceptual design for a Multi-Object Optical and Near-infrared Spectrograph for the Very Large Telescope (VLT), selected by ESO for a Phase A study. The baseline design consists of ~1000 fibers deployable over a field of view of ~500 square arcmin, the largest patrol field offered by

  8. Cosmic rays and terrestrial life: A brief review

    Science.gov (United States)

    Atri, Dimitra; Melott, Adrian L.

    2014-01-01

    “The investigation into the possible effects of cosmic rays on living organisms will also offer great interest.” - Victor F. Hess, Nobel Lecture, December 12, 1936 High-energy radiation bursts are commonplace in our Universe. From nearby solar flares to distant gamma ray bursts, a variety of physical processes accelerate charged particles to a wide range of energies, which subsequently reach the Earth. Such particles contribute to a number of physical processes occurring in the Earth system. A large fraction of the energy of charged particles gets deposited in the atmosphere, ionizing it, causing changes in its chemistry and affecting the global electric circuit. Remaining secondary particles contribute to the background dose of cosmic rays on the surface and parts of the subsurface region. Life has evolved over the past ∼3 billion years in presence of this background radiation, which itself has varied considerably during the period [1-3]. As demonstrated by the Miller-Urey experiment, lightning plays a very important role in the formation of complex organic molecules, which are the building blocks of more complex structures forming life. There is growing evidence of increase in the lightning rate with increasing flux of charged particles. Is there a connection between enhanced rate of cosmic rays and the origin of life? Cosmic ray secondaries are also known to damage DNA and cause mutations, leading to cancer and other diseases. It is now possible to compute radiation doses from secondary particles, in particular muons and neutrons. Have the variations in cosmic ray flux affected the evolution of life on earth? We describe the mechanisms of cosmic rays affecting terrestrial life and review the potential implications of the variation of high-energy astrophysical radiation on the history of life on earth.

  9. Propagation of cosmic rays in the Earth's atmosphere

    International Nuclear Information System (INIS)

    Putze, Antje

    2006-06-01

    Cosmic rays are composed of charged particles, which arrive after a long travel through the Galaxy on Earth. Supernova explosions are considered to be galactic sources, which accelerate these particles up to energies around 10 18 eV. Beyond this energy, one supposes that the extragalactic sources, like active galaxy nuclei (AGN), gamma ray bursts or pulsars, are the origin of the ultra high energy cosmic rays. The spectral index of the elemental energy distributions of cosmic rays reflects the dynamic of its propagation, particularly the conjugation of the effects connected to the cosmic ray source spectrum and those connected to its propagation (acceleration, absorption and escape). The evolution of the spectral index with the cosmic-ray particle energy constitutes a sensitive test of the components, which determine this evolution. The precise index measurement of individual elemental spectra of the cosmic rays by AMS up to TeV and by the experiment CREAM beyond it, from TeV to PeV, will permit to proceed in this problematic. One of the difficulties on this measurement is to take well into account the systematic errors. During the data analysis we have to take into account in particular the interaction (diffusion and fragmentation) of the ions while their travel through the Earth's atmosphere. The study of the interaction and the fragmentation of these ions in the atmosphere is hence indispensable and described in this work. The study is based on a matrix calculation, which had been successfully implemented and tested and which has permitted to analyse the effects, caused by the experimental uncertainties on the cross sections, on the spectral index measurement. (author)

  10. DNA Sequencing and Predictions of the Cosmic Theory of Life

    Science.gov (United States)

    Wickramasinghe, N. Chandra

    The theory of cometary panspermia, developed by the late Sir Fred Hoyle and the present author argues that life originated cosmically as a unique event in one of a great multitude of comets or planetary bodies in the Universe. Life on Earth did not originate here but was introduced by impacting comets, and its further evolution was driven by the subsequent acquisition of cosmically derived genes. Explicit predictions of this theory published in 1979-1981, stating how the acquisition of new genes drives evolution, are compared with recent developments in relation to horizontal gene transfer, and the role of retroviruses in evolution. Precisely-stated predictions of the theory of cometary panspermia are shown to have been verified.

  11. Exploring cosmic origins with CORE: Mitigation of systematic effects

    Science.gov (United States)

    Natoli, P.; Ashdown, M.; Banerji, R.; Borrill, J.; Buzzelli, A.; de Gasperis, G.; Delabrouille, J.; Hivon, E.; Molinari, D.; Patanchon, G.; Polastri, L.; Tomasi, M.; Bouchet, F. R.; Henrot-Versillé, S.; Hoang, D. T.; Keskitalo, R.; Kiiveri, K.; Kisner, T.; Lindholm, V.; McCarthy, D.; Piacentini, F.; Perdereau, O.; Polenta, G.; Tristram, M.; Achucarro, A.; Ade, P.; Allison, R.; Baccigalupi, C.; Ballardini, M.; Banday, A. J.; Bartlett, J.; Bartolo, N.; Basak, S.; Baumann, D.; Bersanelli, M.; Bonaldi, A.; Bonato, M.; Boulanger, F.; Brinckmann, T.; Bucher, M.; Burigana, C.; Cai, Z.-Y.; Calvo, M.; Carvalho, C.-S.; Castellano, M. G.; Challinor, A.; Chluba, J.; Clesse, S.; Colantoni, I.; Coppolecchia, A.; Crook, M.; D'Alessandro, G.; de Bernardis, P.; De Zotti, G.; Di Valentino, E.; Diego, J.-M.; Errard, J.; Feeney, S.; Fernandez-Cobos, R.; Finelli, F.; Forastieri, F.; Galli, S.; Genova-Santos, R.; Gerbino, M.; González-Nuevo, J.; Grandis, S.; Greenslade, J.; Gruppuso, A.; Hagstotz, S.; Hanany, S.; Handley, W.; Hernandez-Monteagudo, C.; Hervías-Caimapo, C.; Hills, M.; Keihänen, E.; Kitching, T.; Kunz, M.; Kurki-Suonio, H.; Lamagna, L.; Lasenby, A.; Lattanzi, M.; Lesgourgues, J.; Lewis, A.; Liguori, M.; López-Caniego, M.; Luzzi, G.; Maffei, B.; Mandolesi, N.; Martinez-González, E.; Martins, C. J. A. P.; Masi, S.; Matarrese, S.; Melchiorri, A.; Melin, J.-B.; Migliaccio, M.; Monfardini, A.; Negrello, M.; Notari, A.; Pagano, L.; Paiella, A.; Paoletti, D.; Piat, M.; Pisano, G.; Pollo, A.; Poulin, V.; Quartin, M.; Remazeilles, M.; Roman, M.; Rossi, G.; Rubino-Martin, J.-A.; Salvati, L.; Signorelli, G.; Tartari, A.; Tramonte, D.; Trappe, N.; Trombetti, T.; Tucker, C.; Valiviita, J.; Van de Weijgaert, R.; van Tent, B.; Vennin, V.; Vielva, P.; Vittorio, N.; Wallis, C.; Young, K.; Zannoni, M.

    2018-04-01

    We present an analysis of the main systematic effects that could impact the measurement of CMB polarization with the proposed CORE space mission. We employ timeline-to-map simulations to verify that the CORE instrumental set-up and scanning strategy allow us to measure sky polarization to a level of accuracy adequate to the mission science goals. We also show how the CORE observations can be processed to mitigate the level of contamination by potentially worrying systematics, including intensity-to-polarization leakage due to bandpass mismatch, asymmetric main beams, pointing errors and correlated noise. We use analysis techniques that are well validated on data from current missions such as Planck to demonstrate how the residual contamination of the measurements by these effects can be brought to a level low enough not to hamper the scientific capability of the mission, nor significantly increase the overall error budget. We also present a prototype of the CORE photometric calibration pipeline, based on that used for Planck, and discuss its robustness to systematics, showing how CORE can achieve its calibration requirements. While a fine-grained assessment of the impact of systematics requires a level of knowledge of the system that can only be achieved in a future study phase, the analysis presented here strongly suggests that the main areas of concern for the CORE mission can be addressed using existing knowledge, techniques and algorithms.

  12. Aerosols Produced by Cosmic Rays

    DEFF Research Database (Denmark)

    Enghoff, Martin Andreas Bødker

    an experiment in order to investigate the underlying microphysical processes. The results of this experiment will help to understand whether ionization from cosmic rays, and by implication the related processes in the universe, has a direct influence on Earth’s atmosphere and climate. Since any physical...... mechanism linking cosmic rays to clouds and climate is currently speculative, there have been various suggestions of the role atmospheric ions may play; these involve any one of a number of processes from the nucleation of aerosols up to the collection processes of cloud droplets. We have chosen to start......Satellite observations have shown that the Earth’s cloud cover is strongly correlated with the galactic cosmic ray flux. While this correlation is indicative of a possible physical connection, there is currently no confirmation that a physical mechanism exists. We are therefore setting up...

  13. Cosmic rays, clouds, and climate

    DEFF Research Database (Denmark)

    Marsh, N.; Svensmark, Henrik

    2000-01-01

    cloud radiative properties. Thus, a moderate influence on atmospheric aerosol distributions from cosmic ray ionisation would have a strong influence on the Earth's radiation budget. Historical evidence over the past 1000 years indicates that changes in climate have occurred in accord with variability......A correlation between a global average of low cloud cover and the flux of cosmic rays incident in the atmosphere has been observed during the last solar cycle. The ionising potential of Earth bound cosmic rays are modulated by the state of the heliosphere, while clouds play an important role...... in the Earth's radiation budget through trapping outgoing radiation and reflecting incoming radiation. If a physical link between these two features can be established, it would provide a mechanism linking solar activity and Earth's climate. Recent satellite observations have further revealed a correlation...

  14. Cosmic Ray Energetics and Mass

    CERN Multimedia

    Baylon cardiel, J L; Wallace, K C; Anderson, T B; Copley, M

    The cosmic-ray energetics and mass (CREAM) investigation is designed to measure cosmic-ray composition to the supernova energy scale of 10$^{15}$ eV in a series of ultra long duration balloon (ULDB) flights. The first flight is planned to be launched from Antarctica in December 2004. The goal is to observe cosmic-ray spectral features and/or abundance changes that might signify a limit to supernova acceleration. The particle ($\\{Z}$) measurements will be made with a timing-based charge detector and a pixelated silicon charge detector to minimize the effect of backscatter from the calorimeter. The particle energy measurements will be made with a transition radiation detector (TRD) for $\\{Z}$ > 3 and a sampling tungsten/scintillator calorimeter for $\\{Z}$ $\\geq$1 particles, allowing inflight cross calibration of the two detectors. The status of the payload construction and flight preparation are reported in this paper.

  15. High-energy cosmic rays

    CERN Document Server

    Cronin, James Watson

    1996-01-01

    Recently two cosmic rays with energy in excess of 2 1020 eV have been recorded. These are some 108 times more energetic than the protons produced by accelerators on earth. There is no credible understanding of the mechanism of acceleration by known a Because of the short mean free path in the cosmic background radiation they must come from nearby distances on a cosmological scale (< 50 Mpc). Their magnetic rigidity suggests that they should point to their source. Lectures will cover the present available data on the highest energy cosmic rays, their detection, possible acceleration mechanisms, their propagation in the galaxy and in extra galactic space and design of new detectors where simulations of air show ers play an important role.

  16. Optical design of a versatile FIRST high-resolution near-IR spectrograph

    Science.gov (United States)

    Zhao, Bo; Ge, Jian

    2012-09-01

    We report the update optical design of a versatile FIRST high resolution near IR spectrograph, which is called Florida IR Silicon immersion grating spectromeTer (FIRST). This spectrograph uses cross-dispersed echelle design with white pupils and also takes advantage of the image slicing to increase the spectra resolution, while maintaining the instrument throughput. It is an extremely high dispersion R1.4 (blazed angle of 54.74°) silicon immersion grating with a 49 mm diameter pupil is used as the main disperser at 1.4μm -1.8μm to produce R=72,000 while an R4 echelle with the same pupil diameter produces R=60,000 at 0.8μm -1.35μm. Two cryogenic Volume Phase Holographic (VPH) gratings are used as cross-dispersers to allow simultaneous wavelength coverage of 0.8μm -1.8μm. The butterfly mirrors and dichroic beamsplitters make a compact folding system to record these two wavelength bands with a 2kx2k H2RG array in a single exposure. By inserting a mirror before the grating disperser (the SIG and the echelle), this spectrograph becomes a very efficient integral field 3-D imaging spectrograph with R=2,000-4,000 at 0.8μm-1.8μm by coupling a 10x10 telescope fiber bundle with the spectrograph. Details about the optical design and performance are reported.

  17. New fermionic dark matters, extended Standard Model and cosmic rays

    Science.gov (United States)

    Hwang, Jae-Kwang

    2017-08-01

    Three generations of leptons and quarks correspond to the lepton charges (LCs) in this work. Then, the leptons have the electric charges (ECs) and LCs. The quarks have the ECs, LCs and color charges (CCs). Three heavy leptons and three heavy quarks are introduced to make the missing third flavor of EC. Then the three new particles which have the ECs are proposed as the bastons (dark matters) with the rest masses of 26.121 eV/c2, 42.7 GeV/c2 and 1.9 × 1015 eV/c2. These new particles are applied to explain the origins of the astrophysical observations like the ultra-high energy cosmic rays and supernova 1987A anti-neutrino data. It is concluded that the 3.5 keV X-ray peak observed from the cosmic X-ray background spectra is originated not from the pair annihilations of the dark matters but from the X-ray emission of the Q1 baryon atoms which are similar in the atomic structure to the hydrogen atom. The presence of the 3.5 keV cosmic X-ray supports the presence of the Q1 quark with the EC of -4/3. New particles can be indirectly seen from the astrophysical observations like the cosmic ray and cosmic gamma ray. In this work, the systematic quantized charges of EC, LC and CC for the elementary particles are used to consistently explain the decay and reaction schemes of the elementary particles. Also, the strong, weak and dark matter forces are consistently explained.

  18. Cosmic very high-energy {gamma}-rays

    Energy Technology Data Exchange (ETDEWEB)

    Plaga, R. [Max-Planck-Institut fur Physik, Muenchen (Germany)

    1998-12-31

    The article gives a brief overview, aimed at nonspecialists, about the goals and selected recent results of the detection of very-high energy {gamma}-rays (energies above 100 GeV) with ground based detectors. The stress is on the physics questions, specially the origin of Galactic Cosmic Rays and the emission of TeV {gamma}-radiation from active galaxies. Moreover some particle-physics questions which are addressed in this area are discussed.

  19. Acceleration and propagation of ultrahigh energy cosmic rays

    International Nuclear Information System (INIS)

    Lemoine, Martin

    2013-01-01

    The origin of the highest energy cosmic rays represents one of the most conspicuous enigmas of modern astrophysics, in spite of gigantic experimental efforts in the past fifty years, and of active theoretical research. The past decade has known exciting experimental results, most particularly the detection of a cut-off at the expected position for the long sought Greisen-Zatsepin-Kuzmin suppression as well as evidence for large scale anisotropies. This paper summarizes and discusses recent achievements in this field.

  20. Acceleration and propagation of ultrahigh energy cosmic rays

    Science.gov (United States)

    Lemoine, Martin

    2013-02-01

    The origin of the highest energy cosmic rays represents one of the most conspicuous enigmas of modern astrophysics, in spite of gigantic experimental efforts in the past fifty years, and of active theoretical research. The past decade has known exciting experimental results, most particularly the detection of a cut-off at the expected position for the long sought Greisen-Zatsepin-Kuzmin suppression as well as evidence for large scale anisotropies. This paper summarizes and discusses recent achievements in this field.

  1. Dust in cosmic plasma environments

    International Nuclear Information System (INIS)

    Mendis, D.A.

    1979-01-01

    Cosmic dust is invariably immersed in a plasma and a radiative environment. Consequently, it is charged to some electrostatic potential which depends on the properties of the environment as well as the nature of the dust. This charging affects the physical and dynamical properties of the dust. In this paper the basic aspects of this dust-plasma interaction in several cosmic environments - including planetary magnetospheres, the heliosphere and the interstellar medium - are discussed. The physical and dynamical consequences of the interaction, as well as the pertinent observational evidence, are reviewed. Finally, the importance of the surface charge during the condensation process in plasma environments is stressed. (Auth.)

  2. Pairing in the cosmic neutrino background

    International Nuclear Information System (INIS)

    Alonso, V.; Paredes, R.

    1981-07-01

    We extend the discussion of the possible superfluidity of the cosmic background of neutrinos beyond the arguments based on the gap equation, originally given by Ginzburg and Zharkov. We show how to develop a simple Ginzburg-Landau liquid model, in analogy with superconductivity. We use it to show how an analysis of the energy spectrum of the universe can be formulated to include general relativistic effects on the superfluid neutrinos. Finally, in view of the Hawking and Collins careful discussion on the rotation and distortion of a spatially homogeneous and isotropic universe, we discuss the vortex dynamics that might be generated on the superfluid by rotations (allowed by the almost isotropy of the microwave background of photons) of up to 2 x 10 -14 second of arc/century, but conclude that rotations of this order of magnitude would be sufficiently strong to deter the existence of the superfluid state. (author)

  3. Ultra-High-Energy Cosmic Rays

    CERN Document Server

    Dova, M.T.

    2015-05-22

    The origin of the ultra high energy cosmic rays (UHECR) with energies above E > 10 17 eV, is still unknown. The discovery of their sources will reveal the engines of the most energetic astrophysical accelerators in the universe. This is a written version of a series of lectures devoted to UHECR at the 2013 CERN-Latin-American School of High-Energy Physics. We present anintroduction to acceleration mechanisms of charged particles to the highest energies in astrophysical objects, their propagation from the sources to Earth, and the experimental techniques for their detection. We also discuss some of the relevant observational results from Telescope Array and Pierre Auger Observatory. These experiments deal with particle interactions at energies orders of magnitude higher than achieved in terrestrial accelerators.

  4. Cosmic thermalization and the microwave background radiation

    International Nuclear Information System (INIS)

    Rana, N.C.

    1981-01-01

    A different origin of the microwave background radiation (MBR) is suggested in view of some of the difficulties associated with the standard interpretation. Extensive stellar-type nucleosynthesis could provide radiation with the requisite energy density of the MBR and its spectral features are guaranteed by adequate thermalization of the above radiation by an ambient intergalactic dust medium. This thermalization must have occurred in quite recent epochs, say around epochs of redshift z = 7. The model emerges with consistent limits on the cosmic abundance of helium, the general luminosity evolution of the extragalactic objects, the baryonic matter density in the Universe (or, equivalently the deceleration parameter) and the degree of isotropy of MBR. The model makes definite predictions on issues like the properties of the intergalactic thermalizers, the degree of isotropy of MBR at submillimetre wavelengths and cluster emission in the far infrared. (author)

  5. Directional clustering in highest energy cosmic rays

    International Nuclear Information System (INIS)

    Goldberg, Haim; Weiler, Thomas J.

    2001-01-01

    An unexpected degree of small-scale clustering is observed in highest-energy cosmic ray events. Some directional clustering can be expected due to purely statistical fluctuations for sources distributed randomly in the sky. This creates a background for events originating in clustered sources. We derive analytic formulas to estimate the probability of random cluster configurations, and use these formulas to study the strong potential of the HiRes, Auger, Telescope Array and EUSO-OWL-AirWatch facilities for deciding whether any observed clustering is most likely due to nonrandom sources. For a detailed comparison to data, our analytical approach cannot compete with Monte Carlo simulations, including experimental systematics. However, our derived formulas do offer two advantages: (i) easy assessment of the significance of any observed clustering, and most importantly, (ii) an explicit dependence of cluster probabilities on the chosen angular bin size

  6. Cosmic inflation constrains scalar dark matter

    Directory of Open Access Journals (Sweden)

    Tommi Tenkanen

    2015-12-01

    Full Text Available In a theory containing scalar fields, a generic consequence is a formation of scalar condensates during cosmic inflation. The displacement of scalar fields out from their vacuum values sets specific initial conditions for post-inflationary dynamics and may lead to significant observational ramifications. In this work, we investigate how these initial conditions affect the generation of dark matter in the class of portal scenarios where the standard model fields feel new physics only through Higgs-mediated couplings. As a representative example, we will consider a $ Z_2 $ symmetric scalar singlet $ s $ coupled to Higgs via $ \\lambda \\Phi ^\\dagger \\Phi s^2 $. This simple extension has interesting consequences as the singlet constitutes a dark matter candidate originating from non-thermal production of singlet particles out from a singlet condensate, leading to a novel interplay between inflationary dynamics and dark matter properties.

  7. Closing CMS to hunt cosmic rays

    CERN Multimedia

    Claudia Marcelloni

    2006-01-01

    Every second the Earth is bombarded by billions of cosmic rays and occasionally one of these cosmic particles will collide with the Earth's atmosphere generating a shower of particles known as an 'air shower'. This is similiar to the collisions and subsequent particle showers observed in accelerators such as the LHC. Here the CMS detector is closed so that systems can be tested using muon cosmic rays in the 'Cosmic Challenge'.

  8. Voids and the Cosmic Web: cosmic depression & spatial complexity

    NARCIS (Netherlands)

    van de Weygaert, Rien; Shandarin, S.; Saar, E.; Einasto, J.

    2016-01-01

    Voids form a prominent aspect of the Megaparsec distribution of galaxies and matter. Not only do theyrepresent a key constituent of the Cosmic Web, they also are one of the cleanest probesand measures of global cosmological parameters. The shape and evolution of voids are highly sensitive tothe

  9. Chandra Discovers Cosmic Cannonball

    Science.gov (United States)

    2007-11-01

    One of the fastest moving stars ever seen has been discovered with NASA's Chandra X-ray Observatory. This cosmic cannonball is challenging theories to explain its blistering speed. Astronomers used Chandra to observe a neutron star, known as RX J0822-4300, over a period of about five years. During that span, three Chandra observations clearly show the neutron star moving away from the center of the Puppis A supernova remnant. This remnant is the stellar debris field created during the same explosion in which the neutron star was created about 3700 years ago. Chandra X-ray Image of RX J0822-4300 in Puppis A Chandra X-ray Image of RX J0822-4300 in Puppis A By combining how far it has moved across the sky with its distance from Earth, astronomers determined the neutron star is moving at over 3 million miles per hour. At this rate, RX J0822-4300 is destined to escape from the Milky Way after millions of years, even though it has only traveled about 20 light years so far. "This star is moving at 3 million miles an hour, but it's so far away that the apparent motion we see in five years is less than the height of the numerals in the date on a penny, seen from the length of a football field," said Frank Winkler of Middlebury College in Vermont. "It's remarkable, and a real testament to the power of Chandra, that such a tiny motion can be measured." Labeled Image of RX J0822-4300 in Puppis A Labeled Image of RX J0822-4300 in Puppis A "Just after it was born, this neutron star got a one-way ticket out of the Galaxy," said co-author Robert Petre of NASA's Goddard Space Flight Center in Greenbelt, Md. "Astronomers have seen other stars being flung out of the Milky Way, but few as fast as this." So-called hypervelocity stars have been previously discovered shooting out of the Milky Way with speeds around one million miles per hour. One key difference between RX J0822-4300 and these other reported galactic escapees is the source of their speed. The hypervelocity stars are

  10. Cosmic Ray Physics with the KASCADE-Grande Observatory

    Science.gov (United States)

    Arteaga-Velázquez, J. C.; Apel, W. D.; Bekk, K.; Bertaina, M.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Cantoni, E.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Fuhrmann, D.; Gherghel-Lascu, A.; Gils, H. J.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Huege, T.; Kampert, K.-H.; Kang, D.; Klages, H. O.; Link, K.; Łuczak, P.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.; Oehlschläger, J.; Ostapchenko, S.; Pierog, T.; Rebel, H.; Roth, M.; Schieler, H.; Schoo, S.; Schröder, F. G.; Sima, O.; Toma, G.; Trinchero, G. C.; Ulrich, H.; Weindl, A.; Wochele, J.; Zabierowski, J.

    The existence of a knee at a few PeV in the all-particle cosmic ray energy spectrum has been well established by several experiments but its physical origin has eluded researches for a long time. It is believed that keys to disentangle the mystery could be found in the spectrum and the composition of cosmic rays between 1 PeV and 1 EeV. A first detailed look into the elemental chemical abundances of cosmic rays in this energy regime was provided by both the KASCADE and the KASCADE-Grande experiments. Their measurements opened the door to a wealth of new data on the subject, which led to the discovery of new structures in the all-particle energy spectrum and the confirmation of knee-like features in the spectra of individual mass groups, as well as the observation of an unexpected ankle-like structure at around 100 PeV in the flux of the light component of cosmic rays. In this contribution, early findings with the KASCADE-Grande experiment will be reviewed and then a short update on the analyses currently performed with the data of the observatory will be presented.

  11. Art and the Cosmic Connection

    Science.gov (United States)

    Cobb, Whitney H.; Aiello, Monica Petty; Macdonald, Reeves; Asplund, Shari

    2014-01-01

    The interdisciplinary unit described in this article utilizes "Art and the Cosmic Connection," a free program conceived of by artists Monica and Tyler Aiello and developed by the artists, scientists, and educators through NASA's Discovery and New Frontiers Programs, to inspire learners to explore mysterious worlds in our solar…

  12. Cosmic-ray sum rules

    International Nuclear Information System (INIS)

    Frandsen, Mads T.; Masina, Isabella; Sannino, Francesco

    2011-01-01

    We introduce new sum rules allowing to determine universal properties of the unknown component of the cosmic rays; we show how they can be used to predict the positron fraction at energies not yet explored by current experiments, and to constrain specific models.

  13. Davis Meeting on Cosmic Inflation

    CERN Document Server

    Kaloper, N; Knox, L; Cosmic Inflation

    2003-01-01

    The Davis Meeting on Cosmic Inflation marked an exciting milestone on the road to precision cosmology. This is the index page for the proceedings of the conference. Individual proceedings contributions, when they appear on this archive, are linked from this page.

  14. Solar-cosmic-ray variability

    International Nuclear Information System (INIS)

    Reedy, R.C.

    1976-01-01

    The maximum flux of particles from solar events that should be considered in designing the shielding for a space habitation is discussed. The activities of various radionuclides measured in the top few centimeters of lunar rocks are used to examine the variability of solar cosmic ray fluxes over the last five million years. 10 references

  15. Delayed recombination and cosmic parameters

    International Nuclear Information System (INIS)

    Galli, Silvia; Melchiorri, Alessandro; Bean, Rachel; Silk, Joseph

    2008-01-01

    Current cosmological constraints from cosmic microwave background anisotropies are typically derived assuming a standard recombination scheme, however additional resonance and ionizing radiation sources can delay recombination, altering the cosmic ionization history and the cosmological inferences drawn from the cosmic microwave background data. We show that for recent observations of the cosmic microwave background anisotropy, from the Wilkinson microwave anisotropy probe satellite mission (WMAP) 5-year survey and from the arcminute cosmology bolometer array receiver experiment, additional resonance radiation is nearly degenerate with variations in the spectral index, n s , and has a marked effect on uncertainties in constraints on the Hubble constant, age of the universe, curvature and the upper bound on the neutrino mass. When a modified recombination scheme is considered, the redshift of recombination is constrained to z * =1078±11, with uncertainties in the measurement weaker by 1 order of magnitude than those obtained under the assumption of standard recombination while constraints on the shift parameter are shifted by 1σ to R=1.734±0.028. From the WMAP5 data we obtain the following constraints on the resonance and ionization sources parameters: ε α i <0.058 at 95% c.l.. Although delayed recombination limits the precision of parameter estimation from the WMAP satellite, we demonstrate that this should not be the case for future, smaller angular scales measurements, such as those by the Planck satellite mission.

  16. Cosmic censorship and the dilaton

    International Nuclear Information System (INIS)

    Horne, J.H.; Horowitz, G.T.

    1993-01-01

    We investigate extremal electrically charged black holes in Einstein-Maxwell-dilaton theory with a cosmological constant inspired by string theory. These solutions are not static, and a timelike singularity eventually appears which is not surrounded by an event horizon. This suggests that cosmic censorship may be violated in this theory

  17. Cosmic censorship and test particles

    International Nuclear Information System (INIS)

    Needham, T.

    1980-01-01

    In this paper one unambiguous prediction of cosmic censorship is put to the test, namely that it should be impossible to destroy a black hole (i.e. eliminate its horizon) by injecting test particles into it. Several authors have treated this problem and have not found their conclusions in contradiction with the prediction. Here we prove that if a general charged spinning particle (with parameters very much smaller than the respective hole parameters) is injected in an arbitrary manner into an extreme Kerr-Newman black hole, then cosmic censorship is upheld. As a by-product of the analysis a natural proof is given of the Christodoulou-Ruffini conditions on the injection of a spinless particle which yield a reversible black-hole transformation. Finally we consider the injection of particles with parameters that are not small compared with those of the hole, for which cosmic censorship is apparently violated. By assuming the validity of cosmic censorship we are led to a few conjectures concerning the extent of the particle's interaction with the hole while approaching it

  18. Cosmology with the cosmic web

    Science.gov (United States)

    Forero-Romero, J. E.

    2017-07-01

    This talk summarizes different algorithms that can be used to trace the cosmic web both in simulations and observations. We present different applications in galaxy formation and cosmology. To finalize, we show how the Dark Energy Spectroscopic Instrument (DESI) could be a good place to apply these techniques.

  19. Clusters and the Cosmic Web

    NARCIS (Netherlands)

    Weygaert, R. van de

    2006-01-01

    Abstract: We discuss the intimate relationship between the filamentary features and the rare dense compact cluster nodes in this network, via the large scale tidal field going along with them, following the cosmic web theory developed Bond et al. The Megaparsec scale tidal shear pattern is

  20. A cosmic book

    International Nuclear Information System (INIS)

    Peebles, P.J.E.; Silk, Joseph

    1988-01-01

    Modern theories of the origin of large-scale structure depend on a variety of stimulating new ideas about the physics of the early Universe. In the absence of clean observational tests one can obtain figures of merit for the theories by counting and weighing the plausibility of each of those basic elements that are not substantially supported by observation or mature fundamental theory. A survey of the speculative elements of the leading rival theories illustrates the exciting and highly uncertain state of research in the physics of the early Universe. (author)

  1. Magnetic spectrograph with a semicircular focusing for studies on the energy distribution of a high-current relativistic electron beam

    International Nuclear Information System (INIS)

    Gosteva, T.S.; Zablotskaya, G.R.; Ivanov, B.A.; Kolyubakin, S.A.; Chernobrovin, V.I.

    1975-01-01

    Specific features of a magnetic spectrograph with a semicircular focusing are described; the spectrograph has been designed to study, using the REP-5 pulsed accelerator, the energy spectra of electrons with a current of 50 kA, pulse duration of 20 ns in the energy range 0.2 to 3 MeV. The beam has been transported in a drift chamber where the air pressure varies from 10 -3 to 40 torr. The chamber is 50 cm long and 12 cm in diameter. The spectrograph vacuum chamber is made in the form of a plane rectangular box with a degassing fitting. The uniform magnetic field in the spectrograph gap is provided with permanent magnets (ferrite-barium plates). The collimator and the chamber walls on which the magnets are located, are made of low-carbon electrotechnical steel. The diameters of the collimator entrance and exit windows are 2 and 0.2 mm, respectively. To screen the photofilm in the spectrograph chamber from x-radiation, there are three disks on the spectrograph flange on the part of the drift chamber, they are made of lead, steel, and aluminium. The steel disk, besides, screens the space in front of the collimator entrance window from the scattered magnetic field. During the experiments the pressure in the spectrograph chamber has varied from 7x10 -3 to 10 -1 torr. Electrons are registered using the RT-1 and RT-5 x-ray films 1x18 cm in size. The spectrograph described makes it possible to have well-resolved electron spectrum during a pulse. The electron spectra obtained by means of the spectrograph at a pressure of 4.10 -1 torr in the drift chamber and a charge voltage of 3.2 MV in the line, are shown [ru

  2. Ultra-High Energy Cosmic Rays (2/3)

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    The origin of the highest energy cosmic rays (UHECR) with energies above 1000 TeV, is still unknown. The discovery of their sources will reveal the engines of the most energetic astrophysical accelerators in the universe. In these lectures we present the recent observational results from HiRes, Telescope Array and Pierre Auger Observatory as well as (some of) the possible astrophysical origins of UHECR. These experiments deal with particle interactions at energies orders of magnitude higher than achieved in terrestrial accelerators.

  3. Ultra-High Energy Cosmic Rays (1/3)

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    The origin of the highest energy cosmic rays (UHECR) with energies above 1000 TeV, is still unknown. The discovery of their sources will reveal the engines of the most energetic astrophysical accelerators in the universe. In these lectures we present the recent observational results from HiRes, Telescope Array and Pierre Auger Observatory as well as (some of) the possible astrophysical origins of UHECR. These experiments deal with particle interactions at energies orders of magnitude higher than achieved in terrestrial accelerators.

  4. Ultra-High Energy Cosmic Rays (3/3)

    CERN Multimedia

    CERN. Geneva

    2012-01-01

    The origin of the highest energy cosmic rays (UHECR) with energies above 1000 TeV, is still unknown. The discovery of their sources will reveal the engines of the most energetic astrophysical accelerators in the universe. In these lectures we present the recent observational results from HiRes, Telescope Array and Pierre Auger Observatory as well as (some of) the possible astrophysical origins of UHECR. These experiments deal with particle interactions at energies orders of magnitude higher than achieved in terrestrial accelerators.

  5. GEMINI NEAR INFRARED FIELD SPECTROGRAPH OBSERVATIONS OF THE SEYFERT 2 GALAXY MRK 573: IN SITU ACCELERATION OF IONIZED AND MOLECULAR GAS OFF FUELING FLOWS

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Travis C.; Straughn, A. N. [Astrophysics Science Division, Goddard Space Flight Center, Code 665, Greenbelt, MD 20771 (United States); Machuca, C.; Crenshaw, D. M.; Baron, F.; Revalski, M.; Pope, C. L. [Department of Physics and Astronomy, Georgia State University, Astronomy Offices, 25 Park Place, Suite 605, Atlanta, GA 30303 (United States); Diniz, M. R.; Riffel, R. A. [Departamento de Física, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS (Brazil); Kraemer, S. B. [Institute for Astrophysics and Computational Sciences, Department of Physics, The Catholic University of America, Washington, DC 20064 (United States); Schmitt, H. R. [Naval Research Laboratory, Washington, DC 20375 (United States); Storchi-Bergmann, T., E-mail: travis.c.fischer@nasa.gov [Departamento de Astronomia, Universidade Federal do Rio Grande do Sul, IF, CP 15051, 91501-970 Porto Alegre, RS (Brazil)

    2017-01-01

    We present near-infrared and optical emission-line and stellar kinematics of the Seyfert 2 galaxy Mrk 573 using the Near-Infrared Field Spectrograph (NIFS) at Gemini North and Dual Imaging Spectrograph at Apache Point Observatory, respectively. By obtaining full kinematic maps of the infrared ionized and molecular gas and stellar kinematics in a ∼700 × 2100 pc{sup 2} circumnuclear region of Mrk 573, we find that kinematics within the Narrow-Line Region are largely due to a combination of both rotation and in situ acceleration of material originating in the host disk. Combining these observations with large-scale, optical long-slit spectroscopy that traces ionized gas emission out to several kpcs, we find that rotation kinematics dominate the majority of the gas. We find that outflowing gas extends to distances less than 1 kpc, suggesting that outflows in Seyfert galaxies may not be powerful enough to evacuate their entire bulges.

  6. E parallel B energy-mass spectrograph for measurement of ions and neutral atoms

    International Nuclear Information System (INIS)

    Funsten, H.O.; McComas, D.J.; Scime, E.E.

    1997-01-01

    Real-time measurement of plasma composition and energy is an important diagnostic in fusion experiments. The Thomson parabola spectrograph described here utilizes an electric field parallel to a magnetic field (E parallel B) and a two-dimensional imaging detector to uniquely identify the energy-per-charge and mass-per-charge distributions of plasma ions. An ultrathin foil can be inserted in front of the E parallel B filter to convert neutral atoms to ions, which are subsequently analyzed using the E parallel B filter. Since helium exiting an ultrathin foil does not form a negative ion and hydrogen isotopes do, this spectrograph allows unique identification of tritium ions and neutrals even in the presence of a large background of 3 He. copyright 1997 American Institute of Physics

  7. Using an integral-field unit spectrograph to study radical species in cometary coma

    Science.gov (United States)

    Lewis, Benjamin; Pierce, Donna M.; Vaughan, Charles M.; Cochran, Anita

    2015-01-01

    We have observed several comets using an integral-field unit spectrograph (the George and Cynthia Mitchell Spectrograph) on the 2.7m Harlan J. Smith telescope at McDonald Observatory. Full-coma spectroscopic images were obtained for various radical species (C2, C3, CN, NH2). Various coma enhancements were used to identify and characterize coma morphological features. The azimuthal average profiles and the Haser model were used to determine production rates and possible parent molecules. Here, we present the work completed to date, and we compare our results to other comet taxonomic surveys. This work was funded by the National Science Foundation Graduate K-12 (GK-12) STEM Fellows program (Award No. DGE-0947419), NASA's Planetary Atmospheres program (Award No. NNX14AH18G), and the Fund for Astrophysical Research, Inc.

  8. New measurements and analysis of high-energy muons in cosmic ray extensive air showers

    International Nuclear Information System (INIS)

    Sarkar, S.K.; Ghose, B.; Murkherjee, N.; Sanyal, S.; Chaudhuri, N.; Chhetri, R.; Basak, D.K.

    1991-01-01

    Cosmic ray air shower structure measurements and measurement of density and energy of air shower muons of a wide energy range simultaneously in individual air showers by two magnet spectrographs are presented. The measured muon densities have been used to compare with some of the previous measurements on muon densities in air showers of nearly the same size. The measured muon densities have also been applied for distinguishing between various interaction models and between light and heavier air shower primaries. In the air shower size range 10 4 -10 6 particles the present measurements do not provide evidence for iron primaries and the different interaction models seem not to be distinguishable by air shower observations. (Author)

  9. Reconstructing matter profiles of spherically compensated cosmic regions in ΛCDM cosmology

    Science.gov (United States)

    de Fromont, Paul; Alimi, Jean-Michel

    2018-02-01

    The absence of a physically motivated model for large-scale profiles of cosmic voids limits our ability to extract valuable cosmological information from their study. In this paper, we address this problem by introducing the spherically compensated cosmic regions, named CoSpheres. Such cosmic regions are identified around local extrema in the density field and admit a unique compensation radius R1 where the internal spherical mass is exactly compensated. Their origin is studied by extending the standard peak model and implementing the compensation condition. Since the compensation radius evolves as the Universe itself, R1(t) ∝ a(t), CoSpheres behave as bubble Universes with fixed comoving volume. Using the spherical collapse model, we reconstruct their profiles with a very high accuracy until z = 0 in N-body simulations. CoSpheres are symmetrically defined and reconstructed for both central maximum (seeding haloes and galaxies) and minimum (identified with cosmic voids). We show that the full non-linear dynamics can be solved analytically around this particular compensation radius, providing useful predictions for cosmology. This formalism highlights original correlations between local extremum and their large-scale cosmic environment. The statistical properties of these spherically compensated cosmic regions and the possibilities to constrain efficiently both cosmology and gravity will be investigated in companion papers.

  10. General method of quantitative spectrographic analysis; Estudio de un metodo general de analisis espectrografico cuantitativo

    Energy Technology Data Exchange (ETDEWEB)

    Capdevila, C; Roca, M

    1966-07-01

    A spectrographic method was developed to determine 23 elements in a wide range of concentrations; the method can be applied to metallic or refractory samples. Previous melting with lithium tetraborate and germanium oxide is done in order to avoid the influence of matrix composition and crystalline structure. Germanium oxide is also employed as internal standard. The resulting beads ar mixed with graphite powder (1:1) and excited in a 10 amperes direct current arc. (Author) 12 refs.

  11. The influence of calcium magnesium, and sodium on the spectrographic analysis of natural waters

    International Nuclear Information System (INIS)

    Diaz Guerra, J. P.; Capdevilla, C.

    1969-01-01

    The influences of 1000 μg/ml of calcium and sodium and 300 μg/ml of magnesium, on the spectrographic determination of Al, Ba, Cr, Fe, Li , Mn, Ni, Pb, Sr and Ti, minor constituents in natural waters, have been studied, In order to eliminate them, the elements Ga, In, La, Ti and Zn, as well as a mixture containing 30 % Tl-70 % In, have been tested as spectrochemical buffers. (Author) 7 refs

  12. Spectrographic observations of solar microwave bursts in the 5.3-7.4 GHz range

    International Nuclear Information System (INIS)

    Kaverin, N.S.; Korshunov, A.I.; Shushunov, V.V.; Aurass, H.; Detlefs, H.; Hartmann, H.; Krueger, A.; Kurths, J.

    1983-01-01

    The first results of the Gorky-type microwave spectrograph of Tremsdorf solar radioastronomy observatory are given, observed after the reconstruction of the instrument to get a higher time resolution for the spectral observations. Two 5.3-7.4 GHz microwave burst spectral diagrams are shown having 20 s time resolution. Broad-bond spectral structures of the microwave burst development have been observed. Explanation of a 'pseudo-drift' phenomenon due to individual peaks is given. (D.Gy.)

  13. First observations from a CCD all-sky spectrograph at Barentsburg (Spitsbergen

    Directory of Open Access Journals (Sweden)

    S. A. Chernouss

    2008-05-01

    Full Text Available A digital CCD all-sky spectrograph was made by the Polar Geophysical Institute (PGI to support IPY activity in auroral research. The device was tested at the Barentsburg observatory of PGI during the winter season of 2005–2006. The spectrograph is based on a cooled CCD and a transmission grating. The main features of this spectrograph are: a wide field of view (~180°, a wide spectral range (380–740 nm, a spectral resolution of 0.6 nm, a background level of about 100 R at 1-min exposure time. Several thousand spectra of nightglow and aurora were recorded during the observation season. It was possible to register both the strong auroral emissions, as well as weak ones. Spectra of aurora, including nitrogen and oxygen molecular and atomic emissions, as well as OH emissions of the nightglow are shown. A comparison has been conducted of auroral spectra obtained by the film all-sky spectral camera C-180-S at Spitsbergen during IGY, with spectra obtained at Barentsburg during the last winter season. The relationship between the red (630.0 nm and green (557.7 nm auroral emissions shows that the green emission is dominant near the minimum of the solar cycle activity (2005–2006. The opposite situation is observed during 1958–1959, with a maximum solar cycle activity.

  14. Opto-mechanical design of an image slicer for the GRIS spectrograph at GREGOR

    Science.gov (United States)

    Vega Reyes, N.; Esteves, M. A.; Sánchez-Capuchino, J.; Salaun, Y.; López, R. L.; Gracia, F.; Estrada Herrera, P.; Grivel, C.; Vaz Cedillo, J. J.; Collados, M.

    2016-07-01

    An image slicer has been proposed for the Integral Field Spectrograph [1] of the 4-m European Solar Telescope (EST) [2] The image slicer for EST is called MuSICa (Multi-Slit Image slicer based on collimator-Camera) [3] and it is a telecentric system with diffraction limited optical quality offering the possibility to obtain high resolution Integral Field Solar Spectroscopy or Spectro-polarimetry by coupling a polarimeter after the generated slit (or slits). Considering the technical complexity of the proposed Integral Field Unit (IFU), a prototype has been designed for the GRIS spectrograph at GREGOR telescope at Teide Observatory (Tenerife), composed by the optical elements of the image slicer itself, a scanning system (to cover a larger field of view with sequential adjacent measurements) and an appropriate re-imaging system. All these subsystems are placed in a bench, specially designed to facilitate their alignment, integration and verification, and their easy installation in front of the spectrograph. This communication describes the opto-mechanical solution adopted to upgrade GRIS while ensuring repeatability between the observational modes, IFU and long-slit. Results from several tests which have been performed to validate the opto-mechanical prototypes are also presented.

  15. A color spectrographic phonocardiography (CSP applied to the detection and characterization of heart murmurs: preliminary results

    Directory of Open Access Journals (Sweden)

    Hassani Kamran

    2011-05-01

    Full Text Available Abstract Background Although cardiac auscultation remains important to detect abnormal sounds and murmurs indicative of cardiac pathology, the application of electronic methods remains seldom used in everyday clinical practice. In this report we provide preliminary data showing how the phonocardiogram can be analyzed using color spectrographic techniques and discuss how such information may be of future value for noninvasive cardiac monitoring. Methods We digitally recorded the phonocardiogram using a high-speed USB interface and the program Gold Wave http://www.goldwave.com in 55 infants and adults with cardiac structural disease as well as from normal individuals and individuals with innocent murmurs. Color spectrographic analysis of the signal was performed using Spectrogram (Version 16 as a well as custom MATLAB code. Results Our preliminary data is presented as a series of seven cases. Conclusions We expect the application of spectrographic techniques to phonocardiography to grow substantially as ongoing research demonstrates its utility in various clinical settings. Our evaluation of a simple, low-cost phonocardiographic recording and analysis system to assist in determining the characteristic features of heart murmurs shows promise in helping distinguish innocent systolic murmurs from pathological murmurs in children and is expected to useful in other clinical settings as well.

  16. Development of micro-mirror slicer integral field unit for space-borne solar spectrographs

    Science.gov (United States)

    Suematsu, Yoshinori; Saito, Kosuke; Koyama, Masatsugu; Enokida, Yukiya; Okura, Yukinobu; Nakayasu, Tomoyasu; Sukegawa, Takashi

    2017-12-01

    We present an innovative optical design for image slicer integral field unit (IFU) and a manufacturing method that overcomes optical limitations of metallic mirrors. Our IFU consists of a micro-mirror slicer of 45 arrayed, highly narrow, flat metallic mirrors and a pseudo-pupil-mirror array of off-axis conic aspheres forming three pseudo slits of re-arranged slicer images. A prototype IFU demonstrates that the final optical quality is sufficiently high for a visible light spectrograph. Each slicer micro-mirror is 1.58 mm long and 30 μm wide with surface roughness ≤1 nm rms, and edge sharpness ≤ 0.1 μm, etc. This IFU is small size and can be implemented in a multi-slit spectrograph without any moving mechanism and fore optics, in which one slit is real and the others are pseudo slits from the IFU. The IFU mirrors were deposited by a space-qualified, protected silver coating for high reflectivity in visible and near IR wavelength regions. These properties are well suitable for space-borne spectrograph such as the future Japanese solar space mission SOLAR-C. We present the optical design, performance of prototype IFU, and space qualification tests of the silver coating.

  17. Mass production of volume phase holographic gratings for the VIRUS spectrograph array

    Science.gov (United States)

    Chonis, Taylor S.; Frantz, Amy; Hill, Gary J.; Clemens, J. Christopher; Lee, Hanshin; Tuttle, Sarah E.; Adams, Joshua J.; Marshall, J. L.; DePoy, D. L.; Prochaska, Travis

    2014-07-01

    The Visible Integral-field Replicable Unit Spectrograph (VIRUS) is a baseline array of 150 copies of a simple, fiber-fed integral field spectrograph that will be deployed on the Hobby-Eberly Telescope (HET). VIRUS is the first optical astronomical instrument to be replicated on an industrial scale, and represents a relatively inexpensive solution for carrying out large-area spectroscopic surveys, such as the HET Dark Energy Experiment (HETDEX). Each spectrograph contains a volume phase holographic (VPH) grating with a 138 mm diameter clear aperture as its dispersing element. The instrument utilizes the grating in first-order for 350 VPH gratings has been mass produced for VIRUS. Here, we present the design of the VIRUS VPH gratings and a discussion of their mass production. We additionally present the design and functionality of a custom apparatus that has been used to rapidly test the first-order diffraction efficiency of the gratings for various discrete wavelengths within the VIRUS spectral range. This device has been used to perform both in-situ tests to monitor the effects of adjustments to the production prescription as well as to carry out the final acceptance tests of the gratings' diffraction efficiency. Finally, we present the as-built performance results for the entire suite of VPH gratings.

  18. The cosmic spiderweb: equivalence of cosmic, architectural and origami tessellations

    Science.gov (United States)

    Hidding, Johan; Konstantatou, Marina; van de Weygaert, Rien

    2018-01-01

    For over 20 years, the term ‘cosmic web’ has guided our understanding of the large-scale arrangement of matter in the cosmos, accurately evoking the concept of a network of galaxies linked by filaments. But the physical correspondence between the cosmic web and structural engineering or textile ‘spiderwebs’ is even deeper than previously known, and also extends to origami tessellations. Here, we explain that in a good structure-formation approximation known as the adhesion model, threads of the cosmic web form a spiderweb, i.e. can be strung up to be entirely in tension. The correspondence is exact if nodes sampling voids are included, and if structure is excluded within collapsed regions (walls, filaments and haloes), where dark-matter multistreaming and baryonic physics affect the structure. We also suggest how concepts arising from this link might be used to test cosmological models: for example, to test for large-scale anisotropy and rotational flows in the cosmos. PMID:29765637

  19. Do coronal holes influence cosmic ray daily harmonics

    International Nuclear Information System (INIS)

    Ahluwalia, H.S.

    1977-01-01

    Coronal holes are identified by their low emissivity in either EUV (Munro and Withrobe, 1973) or in X-rays (Krieger et al, 1973). They are seats of unidirectional magnetic fields. Also, high speed solar wind streams originate in them. Also, high speed solar wind streams originate in then (Krieger et al, 1973; Neupert and Pizzo, 1974; Nolte et al, 1976). Coronal holes often extend over a wide range of heliolatitudes (Timothy et al, 1975). Elsewhere in the Proceedings we have presented results on the long term changes observed in the amplitudes and the times of maximum of the diurnal, the semidiurnal and the tridiurnal variations of cosmic rays, at low (neutrons) and at high (underground muons) primary rigidities (Ahluwalia, 1977). We have shown that a dramatic shift to early hours is noticeable in the times of maxima of the harmonics during 1971-72 period. In this paper we examine the nature of the contributions of off-ecliptic cosmic rays of high enough rigidity, streaming under the influence of large scale ordered interplanetary magnetic field set up by the coronal holes, to the cosmic ray daily harmonics. Some models are presented and discussed in a preliminary fashion. (author)

  20. Large scale CMB anomalies from thawing cosmic strings

    Energy Technology Data Exchange (ETDEWEB)

    Ringeval, Christophe [Centre for Cosmology, Particle Physics and Phenomenology, Institute of Mathematics and Physics, Louvain University, 2 Chemin du Cyclotron, 1348 Louvain-la-Neuve (Belgium); Yamauchi, Daisuke; Yokoyama, Jun' ichi [Research Center for the Early Universe (RESCEU), Graduate School of Science, The University of Tokyo, Tokyo 113-0033 (Japan); Bouchet, François R., E-mail: christophe.ringeval@uclouvain.be, E-mail: yamauchi@resceu.s.u-tokyo.ac.jp, E-mail: yokoyama@resceu.s.u-tokyo.ac.jp, E-mail: bouchet@iap.fr [Institut d' Astrophysique de Paris, UMR 7095-CNRS, Université Pierre et Marie Curie, 98bis boulevard Arago, 75014 Paris (France)

    2016-02-01

    Cosmic strings formed during inflation are expected to be either diluted over super-Hubble distances, i.e., invisible today, or to have crossed our past light cone very recently. We discuss the latter situation in which a few strings imprint their signature in the Cosmic Microwave Background (CMB) Anisotropies after recombination. Being almost frozen in the Hubble flow, these strings are quasi static and evade almost all of the previously derived constraints on their tension while being able to source large scale anisotropies in the CMB sky. Using a local variance estimator on thousand of numerically simulated Nambu-Goto all sky maps, we compute the expected signal and show that it can mimic a dipole modulation at large angular scales while being negligible at small angles. Interestingly, such a scenario generically produces one cold spot from the thawing of a cosmic string loop. Mixed with anisotropies of inflationary origin, we find that a few strings of tension GU = O(1) × 10{sup −6} match the amplitude of the dipole modulation reported in the Planck satellite measurements and could be at the origin of other large scale anomalies.