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Author Jueid, A.; Kip, J.; Ruiz de Austri, R.; Skands, P.
Title The Strong Force meets the Dark Sector: a robust estimate of QCD uncertainties for anti-matter dark matter searches Type Journal Article
Year 2024 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 02 Issue 2 Pages 119 - 48pp
Keywords Cosmic Rays; Particle Nature of Dark Matter; Specific QCD Phenomenology
Abstract (down) In dark-matter annihilation channels to hadronic final states, stable particles – such as positrons, photons, antiprotons, and antineutrinos – are produced via complex sequences of phenomena including QED/QCD radiation, hadronisation, and hadron decays. These processes are normally modelled by Monte Carlo (MC) event generators whose limited accuracy imply intrinsic QCD uncertainties on the predictions for indirect-detection experiments like Fermi-LAT, Pamela, IceCube or Ams-02. In this article, we perform a comprehensive analysis of QCD uncertainties, meaning both perturbative and nonperturbative sources of uncertainty are included – estimated via variations of MC renormalization-scale and fragmentation-function parameters, respectively – in antimatter spectra from dark-matter annihilation, based on parametric variations of the Pythia 8 event generator. After performing several retunings of light-quark fragmentation functions, we define a set of variations that span a conservative estimate of the QCD uncertainties. We estimate the effects on antimatter spectra for various annihilation channels and final-state particle species, and discuss their impact on fitted values for the dark-matter mass and thermally-averaged annihilation cross section. We find dramatic impacts which can go up to O(10%) for the annihilation cross section. We provide the spectra in tabulated form including QCD uncertainties and code snippets to perform fast dark-matter fits, in this github repository.
Address [Jueid, Adil] Inst Basic Sci IBS, Ctr Theoret Phys Universe, Particle Theory & Cosmol Grp, Daejeon 34126, South Korea, Email: adiljueid@ibs.re.kr;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:001165531600003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5956
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Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S.
Title Update on the correlation of the highest energy cosmic rays with nearby extragalactic matter Type Journal Article
Year 2010 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.
Volume 34 Issue 5 Pages 314-326
Keywords Cosmic rays; UHECR; Anisotropy; Pierre Auger Observatory; Extra-galactic; GZK
Abstract (down) Data collected by the Pierre Auger Observatory through 31 August 2007 showed evidence for anisotropy in the arrival directions of cosmic rays above the Greisen-Zatsepin-Kuz'min energy threshold, 6 x 10(19) eV. The anisotropy was measured by the fraction of arrival directions that are less than 3.1 degrees from the position of an active galactic nucleus within 75 Mpc (using the Veron-Cetty and Veron 12th catalog). An updated measurement of this fraction is reported here using the arrival directions of cosmic rays recorded above the same energy threshold through 31 December 2009. The number of arrival directions has increased from 27 to 69, allowing a more precise measurement. The correlating fraction is (38(-6)(+7))%, compared with 21% expected for isotropic cosmic rays. This is down from the early estimate of (69-(+11)(13))%. The enlarged set of arrival directions is examined also in relation to other populations of nearby extragalactic objects: galaxies in the 2 Microns All Sky Survey and active galactic nuclei detected in hard X-rays by the Swift Burst Alert Telescope. A celestial region around the position of the radiogalaxy Cen A has the largest excess of arrival directions relative to isotropic expectations. The 2-point autocorrelation function is shown for the enlarged set of arrival directions and compared to the isotropic expectation.
Address [Allekotte, I.; Asorey, H.; Bertou, X.; Golup, G.; Gomez Berisso, M.; Harari, D.; Mollerach, S.; Ponce, V. H.; Roulet, E.] Ctr Atom Bariloche, San Carlos De Bariloche, Rio Negro, Argentina
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 Expedition Conference
Notes ISI:000284669100007 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 320
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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 (down) 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 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 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 (down) 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 Expedition Conference
Notes WOS:000311217000052 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1218
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Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S.
Title Constraints on the origin of cosmic rays above 10^18 eV from large-scale anisotropy searches in data of the Pierre Auger Observatory Type Journal Article
Year 2013 Publication Astrophysical Journal Letters Abbreviated Journal Astrophys. J. Lett.
Volume 762 Issue 1 Pages L13 - 8pp
Keywords astroparticle physics; cosmic rays
Abstract (down) A thorough search for large-scale anisotropies in the distribution of arrival directions of cosmic rays detected above 10(18) eV at the Pierre Auger Observatory is reported. For the first time, these large-scale anisotropy searches are performed as a function of both the right ascension and the declination and expressed in terms of dipole and quadrupole moments. Within the systematic uncertainties, no significant deviation from isotropy is revealed. Upper limits on dipole and quadrupole amplitudes are derived under the hypothesis that any cosmic ray anisotropy is dominated by such moments in this energy range. These upper limits provide constraints on the production of cosmic rays above 10(18) eV, since they allow us to challenge an origin from stationary galactic sources densely distributed in the galactic disk and emitting predominantly light particles in all directions.
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 Expedition Conference
Notes WOS:000312488400013 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1279
Permanent link to this record