Measurement of the Cosmic Ray Spectrum above 4 $\times$ 10$^{18}$ eV Using Inclined Events Detected with the Pierre Auger Observatory

Aab, Alexander; Abreu, Pedro; Aglietta, Marco; Ahn, Eun-Joo; Al Samarai, Imen; Albuquerque, Ivone; Allekotte, Ingomar; Allison, Patrick; Almela, Alejandro; Alvarez Castillo, Jesus

doi:10.1088/1475-7516/2015/08/049

Measurement of the Cosmic Ray Spectrum above 4 $\times$ 10 $^{18}$ eV Using Inclined Events Detected with the Pierre Auger Observatory

Pierre Auger

Collaboration

Mar 26, 2015

22 pages

Published in:

JCAP 08 (2015) 049

Published: Aug 26, 2015

e-Print:

1503.07786 [astro-ph.HE]

DOI:

10.1088/1475-7516/2015/08/049

Report number:

FERMILAB-PUB-15-099-AD-AE-CD-TD

Experiments:

AUGER

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Abstract: (IOP)

A measurement of the cosmic-ray spectrum for energies exceeding 4×10(18) eV is presented, which is based on the analysis of showers with zenith angles greater than 60° detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above 5.3×10(18) eV, the ``ankle'', the flux can be described by a power law E(−)(γ) with index γ=2.70 ± 0.02 (stat) ± 0.1 (sys) followed by a smooth suppression region. For the energy (E(s)) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find E(s)=(5.12±0.25 (stat)(+1.0)(−)(1.2) (sys))×10(19) eV.

Note:

Replaced with published version. Added journal reference and DOI

cosmic radiation: spectrum
cosmic radiation: energy spectrum
cosmic radiation: UHE
suppression
cosmic radiation: flux
observatory
Auger
spectral
showers

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