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Author Fornengo, N.; Lineros, R.A.; Regis, M.; Taoso, M.
Title Galactic synchrotron emission from WIMPs at radio frequencies Type Journal Article
Year 2012 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 01 Issue 1 Pages 005 - 25pp
Keywords dark matter theory; cosmic ray theory; absorption and radiation processes
Abstract Dark matter annihilations in the Galactic halo inject relativistic electrons and positrons which in turn generate a synchrotron radiation when interacting with the galactic magnetic field. We calculate the synchrotron flux for various dark matter annihilation channels, masses, and astrophysical assumptions in the low-frequency range and compare our results with radio surveys from 22 MHz to 1420 MHz. We find that current observations are able to constrain particle dark matter with “thermal” annihilation cross-sections, i.e. (sigma v) = 3 x 10(-26) cm(3) s(-1); and masses M-DM less than or similar to 10 GeV. We discuss the dependence of these bounds on the astrophysical assumptions, namely galactic dark matter distribution, cosmic rays propagation parameters, and structure of the galactic magnetic field. Prospects for detection in future radio surveys are outlined.
Address [Fornengo, Nicolao; Regis, Marco] Univ Turin, Dipartimento Fis Teor, Ist Nazl Fis Nucl, I-10125 Turin, Italy, Email: fornengo@to.infn.it
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area (up) Expedition Conference
Notes WOS:000300403300005 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 939
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Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S.
Title Description of atmospheric conditions at the Pierre Auger Observatory using the Global Data Assimilation System (GDAS) Type Journal Article
Year 2012 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.
Volume 35 Issue 9 Pages 591-607
Keywords Cosmic rays; Extensive air showers; Atmospheric monitoring; Atmospheric models
Abstract Atmospheric conditions at the site of a cosmic ray observatory must be known for reconstructing observed extensive air showers. The Global Data Assimilation System (GDAS) is a global atmospheric model predicated on meteorological measurements and numerical weather predictions. GDAS provides altitude-dependent profiles of the main state variables of the atmosphere like temperature, pressure, and humidity. The original data and their application to the air shower reconstruction of the Pierre Auger Observatory are described. By comparisons with radiosonde and weather station measurements obtained on-site in Malargue and averaged monthly models, the utility of the GDAS data is shown.
Address [Baeuml, J.; Bluemer, H.; Daumiller, K.; Engel, R.; Gonzalez, J. G.; Haungs, A.; Heck, D.; Huege, T.; Keilhauer, B.; Klages, H. O.; Kleinfeller, J.; Mathes, H. J.; Maurel, D.; Oehlschlaeger, J.; Pierog, T.; Porcelli, A.; Roth, M.; Schieler, H.; Schroeder, F.; Smida, R.; Szuba, M.; Ulrich, R.; Unger, M.; Weindl, A.; Werner, F.; Will, M.; Wommer, M.] Karlsruhe Inst Technol, Inst Kernphys, Karlsruhe, Germany, Email: bianca.keilhauer@kit.edu
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0927-6505 ISBN Medium
Area (up) Expedition Conference
Notes WOS:000302109200006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 965
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Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S.
Title A search for anisotropy in the arrival directions of ultra high energy cosmic rays recorded at the Pierre Auger Observatory Type Journal Article
Year 2012 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 04 Issue 4 Pages 040 - 21pp
Keywords ultra high energy cosmic rays; cosmic ray experiments
Abstract Observations of cosmic rays arrival directions made with the Pierre Auger Observatory have previously provided evidence of anisotropy at the 99% CL using the correlation of ultra high energy cosmic rays (UHECRs) with objects drawn from the Veron-Cetty Veron catalog. In this paper we report on the use of three catalog independent methods to search for anisotropy. The 2pt-L, 2pt+ and 3pt methods, each giving a different measure of self-clustering in arrival directions, were tested on mock cosmic ray data sets to study the impacts of sample size and magnetic smearing on their results, accounting for both angular and energy resolutions. If the sources of UHECRs follow the same large scale structure as ordinary galaxies in the local Universe and if UHECRs are deflected no more than a few degrees, a study of mock maps suggests that these three method can efficiently respond to the resulting anisotropy with a P-value = 1.0% or smaller with data sets as few as 100 events. using data taken from January 1, 2004 to July 31, 2010 we examined the 20, 30, ... , 110 highest energy events with a corresponding minimum energy threshold of about 49.3 EeV. The minimum P-values found were 13.5% using the 2pt-L method, 1.0% using the 2pt+ method and 1.1% using the 3pt method for the highest 100 energy events. In view of the multiple (correlated) scans performed on the data set, these catalog-independent methods do not yield strong evidence of anisotropy in the highest energy cosmic rays.
Address [Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadana, J.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Santos, E.; Tome, B.] Univ Tecn Lisboa, LIP, P-1100 Lisbon, Portugal, Email: auger_spokesperson@fnal.gov
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area (up) Expedition Conference
Notes WOS:000303665000040 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1015
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Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S.
Title Search for Point-like Sources of Ultra-high Energy Neutrinos at the Pierre Auger Observatory and Improved Limit on the Diffuse Flux of Tau Neutrinos Type Journal Article
Year 2012 Publication Astrophysical Journal Letters Abbreviated Journal Astrophys. J. Lett.
Volume 755 Issue 1 Pages L4 - 7pp
Keywords astroparticle physics; cosmic rays; neutrinos; telescopes
Abstract The surface detector array of the Pierre Auger Observatory can detect neutrinos with energy E-nu between 10(17) eV and 10(20) eV from point-like sources across the sky south of +55 degrees and north of -65 degrees declinations. A search has been performed for highly inclined extensive air showers produced by the interaction of neutrinos of all flavors in the atmosphere (downward-going neutrinos), and by the decay of tau leptons originating from tau neutrino interactions in Earth's crust (Earth-skimming neutrinos). No candidate neutrinos have been found in data up to 2010 May 31. This corresponds to an equivalent exposure of similar to 3.5 years of a full surface detector array for the Earth-skimming channel and similar to 2 years for the downward-going channel. An improved upper limit on the diffuse flux of tau neutrinos has been derived. Upper limits on the neutrino flux from point-like sources have been derived as a function of the source declination. Assuming a differential neutrino flux k(PS) . E-nu(-2). from a point-like source, 90% confidence level upper limits for k(PS) at the level of approximate to 5x10(-7) and 2.5x10(-6) GeV cm(-2) s(-1) have been obtained over a broad range of declinations from the searches for Earth-skimming and downward-going neutrinos, respectively.
Address [Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadanal, J.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Santos, E.; Tome, B.] Univ Tecn Lisboa, LIP, Lisbon, Portugal
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2041-8205 ISBN Medium
Area (up) Expedition Conference
Notes WOS:000306930700004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1121
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Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S.
Title A search for point sources of EeV neutrons Type Journal Article
Year 2012 Publication Astrophysical Journal Abbreviated Journal Astrophys. J.
Volume 760 Issue 2 Pages 148 - 11pp
Keywords cosmic rays; Galaxy: disk; methods: data analysis
Abstract A thorough search of the sky exposed at the Pierre Auger Cosmic Ray Observatory reveals no statistically significant excess of events in any small solid angle that would be indicative of a flux of neutral particles from a discrete source. The search covers from -90 degrees to +15 degrees in declination using four different energy ranges above 1 EeV (10(18) eV). The method used in this search is more sensitive to neutrons than to photons. The upper limit on a neutron flux is derived for a dense grid of directions for each of the four energy ranges. These results constrain scenarios for the production of ultrahigh energy cosmic rays in the Galaxy.
Address [Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Diogo, F.; Espadanal, J.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Santos, E.; Tome, B.] Univ Tecn Lisboa, LIP, Lisbon, Portugal
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-637x ISBN Medium
Area (up) Expedition Conference
Notes WOS:000311217000052 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1218
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