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Title: Large scale distribution of ultra high energy cosmic rays detected at the Pierre Auger Observatory with zenith angles up to 80°

Abstract

In this study, we present the results of an analysis of the large angular scale distribution of the arrival directions of cosmic rays with energy above 4 EeV detected at the Pierre Auger Observatory including for the first time events with zenith angle between 60° and 80°. We perform two Rayleigh analyses, one in the right ascension and one in the azimuth angle distributions, that are sensitive to modulations in right ascension and declination, respectively. The largest departure from isotropy appears in the $$E\gt 8$$ EeV energy bin, with an amplitude for the first harmonic in right ascension $$r_{1}^{\alpha }=(4.4\pm 1.0)\times {{10}^{-2}}$$, that has a chance probability $$P(\geqslant r_{1}^{\alpha })=6.4\times {{10}^{-5}}$$, reinforcing the hint previously reported with vertical events alone.

Authors:
 [1]
  1. Univ. Siegen, Siegen (Germany). et al.
Publication Date:
Research Org.:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Org.:
The Pierre Auger Collaboration
OSTI Identifier:
1234871
Report Number(s):
FERMILAB-PUB-14-488-AD-AE-CD-TD
Journal ID: ISSN 1538-4357; arXiv eprint number arXiv:1411.6953
Grant/Contract Number:  
AC02-07CH11359
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
The Astrophysical Journal
Additional Journal Information:
Journal Volume: 802; Journal Issue: 2; Journal ID: ISSN 1538-4357
Publisher:
Institute of Physics (IOP)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; astroparticle physics; cosmic rays

Citation Formats

Aab, Alexander. Large scale distribution of ultra high energy cosmic rays detected at the Pierre Auger Observatory with zenith angles up to 80°. United States: N. p., 2015. Web. doi:10.1088/0004-637X/802/2/111.
Aab, Alexander. Large scale distribution of ultra high energy cosmic rays detected at the Pierre Auger Observatory with zenith angles up to 80°. United States. doi:10.1088/0004-637X/802/2/111.
Aab, Alexander. Mon . "Large scale distribution of ultra high energy cosmic rays detected at the Pierre Auger Observatory with zenith angles up to 80°". United States. doi:10.1088/0004-637X/802/2/111. https://www.osti.gov/servlets/purl/1234871.
@article{osti_1234871,
title = {Large scale distribution of ultra high energy cosmic rays detected at the Pierre Auger Observatory with zenith angles up to 80°},
author = {Aab, Alexander},
abstractNote = {In this study, we present the results of an analysis of the large angular scale distribution of the arrival directions of cosmic rays with energy above 4 EeV detected at the Pierre Auger Observatory including for the first time events with zenith angle between 60° and 80°. We perform two Rayleigh analyses, one in the right ascension and one in the azimuth angle distributions, that are sensitive to modulations in right ascension and declination, respectively. The largest departure from isotropy appears in the $E\gt 8$ EeV energy bin, with an amplitude for the first harmonic in right ascension $r_{1}^{\alpha }=(4.4\pm 1.0)\times {{10}^{-2}}$, that has a chance probability $P(\geqslant r_{1}^{\alpha })=6.4\times {{10}^{-5}}$, reinforcing the hint previously reported with vertical events alone.},
doi = {10.1088/0004-637X/802/2/111},
journal = {The Astrophysical Journal},
number = 2,
volume = 802,
place = {United States},
year = {Mon Mar 30 00:00:00 EDT 2015},
month = {Mon Mar 30 00:00:00 EDT 2015}
}

Journal Article:
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Cited by: 27 works
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