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An upper limit on the cosmic-ray luminosity of individual sources from gamma-ray observations
(Institute of Physics - IOPBristol, 2013-12)
Different types of extragalactic objects are known to produce TeV gamma-rays. Some of these objects are the most probable candidates to accelerate cosmic rays up to '10 POT.20' eV. It is very well known that gamma-rays can ...
A faraway quasar in the direction of the highest energy Auger event
(IOP PUBLISHING LTD, 2010)
The highest energy cosmic ray event reported by the Auger Observatory has an energy of 148 EeV. It does not correlate with any nearby (z<0.024) object capable of originating such a high energy event. Intrigued by the fact ...
Bounds on the density of sources of ultra-high energy cosmic rays from the Pierre Auger Observatory
(Institute of Physics - IOPBristol, 2013-05)
We derive lower bounds on the density of sources of ultra-high energy cosmic rays from the lack of significant clustering in the arrival directions of the highest energy events detected at the Pierre Auger Observatory. The ...
Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory
(Institute of Physics - IOPBristol, 2011-06)
The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > Eth = 5.5 × 1019 eV. These show a correlation with the distribution of ...
An upper limit on the cosmic-ray luminosity of individual sources from gamma-ray observations
(Iop Publishing, 2013-12)
Different types of extragalactic objects are known to produce TeV gamma-rays. Some of these objects are the most probable candidates to accelerate cosmic rays up to 1020 eV. It is very well known that gamma-rays can be ...
A search for anisotropy in the arrival directions of ultra high energy cosmic rays recorded at the Pierre Auger Observatory
(Institute of Physics - IOPBristol, 2012-04)
Observations of cosmic ray arrival directions made with the Pierre Auger Obser- vatory have previously provided evidence of anisotropy at the 99% CL using the correlation of ultra high energy cosmic rays (UHECRs) with ...
Interpretation of the depths of maximum of extensive air showers measured by the Pierre Auger Observatory
(Institute of Physics - IOPBristol, 2013-02)
To interpret the mean depth of cosmic ray air shower maximum and its dispersion, we parametrize those two observables as functions of the rst two moments of the lnA distribution. We examine the goodness of this simple ...
KASCADE-Grande measurements of energy spectra for elemental groups of cosmic rays
(Elsevier BVAmsterdam, 2013-07)
The KASCADE-Grande air shower experiment [1] consists of, among others, a large scintillator array for measurements of charged particles, Nch, and of an array of shielded scintillation counters used for muon counting, Nµ. ...
The wavefront of the radio signal emitted by cosmic ray air showers
(Institute of Physics - IOPBristol, 2014-09)
Analyzing measurements of the LOPES antenna array together with corresponding CoREAS simulations for more than 300 measured events with energy above '10 POT. 17' eV and zenith angles smaller than 45◦, we find that the radio ...