3 research outputs found
Measurement of the cosmic ray energy spectrum using hybrid events of the Pierre Auger Observatory
The energy spectrum of ultra-high energy cosmic rays above 1018 eV is measured using the hybrid events collected by the Pierre Auger Observatory between November 2005 and September 2010. The large exposure of the Observatory allows the measurement of the main features of the energy spectrum with high statistics. Full Monte Carlo simulations of the extensive air showers (based on the CORSIKA code) and of the hybrid detector response are adopted here as an independent cross check of the standard analysis (Phys. Lett. B 685, 239 (2010)). The dependence on mass composition and other systematic uncertainties are discussed in detail and, in the full Monte Carlo approach, a region of confidence for flux measurements is defined when all the uncertainties are taken into account. An update is also reported of the energy spectrum obtained by combining the hybrid spectrum and that measured using the surface detector array. © 2012 Società Italiana di Fisica and Springer
Search for High-energy Neutrinos from Binary Neutron Star Merger GW170817 with ANTARES, IceCube, and the Pierre Auger Observatory
The Advanced LIGO and Advanced Virgo observatories recently discovered
gravitational waves from a binary neutron star inspiral. A short gamma-ray
burst (GRB) that followed the merger of this binary was also recorded by the
Fermi Gamma-ray Burst Monitor (Fermi-GBM), and the Anticoincidence Shield for
the Spectrometer for the International Gamma-Ray Astrophysics Laboratory
(INTEGRAL), indicating particle acceleration by the source. The precise
location of the event was determined by optical detections of emission
following the merger. We searched for high-energy neutrinos from the merger in
the GeV--EeV energy range using the ANTARES, IceCube, and Pierre Auger
Observatories. No neutrinos directionally coincident with the source were
detected within s around the merger time. Additionally, no MeV
neutrino burst signal was detected coincident with the merger. We further
carried out an extended search in the direction of the source for high-energy
neutrinos within the 14-day period following the merger, but found no evidence
of emission. We used these results to probe dissipation mechanisms in
relativistic outflows driven by the binary neutron star merger. The
non-detection is consistent with model predictions of short GRBs observed at a
large off-axis angle.Comment: 22 pages, 2 figure
Calibration and Monitoring of the Pierre Auger Observatory
Contributions to the 31st International Cosmic Ray Conference, Lodz, Poland, July 2009International audienceReports on the atmospheric monitoring, calibration, and other operating systems of the Pierre Auger Observatory. Contributions to the 31st International Cosmic Ray Conference, Lodz, Poland, July 2009