Large-scale distribution in arrival directions of UHECRs detected at the Pierre Auger Observatory, and study of the Molecular Bremsstrahlung Radiation as a GHz radio emission process to estimate the primary mass of extensive air showers

par Imen Al Samarai (IPNO)

lundi 2 févr. 2015, 14:00 → 15:00 Europe/Paris

Amphithéâtre (CPPM)

The Pierre Auger Observatory (PAO) is the largest Ultra-High Energy (UHE) Cosmic Ray (CR) detector up to date. The search for anisotropies in the arrival direction of CRs at large scales might give important hints about CR production sites. The data of the Observatory would soon confirm a signal in the direction of the Galactic Center at energies below ~10^18 eV. This would provide a signature of the CRs origin at these energies. In this seminar, I will present the related analysis and the astrophysical implications of these results. Meanwhile, due to the scarcity of particles at UHE and the limited duty-cycle of fluorescence telescopes, novel techniques of detection of Extensive Air Showers (EAS) are being developed in PAO in order to measure the CR mass composition. One of these techniques is based on the Molecular Bremsstrahlung Radiation (MBR) in the GHz bandwidth. I will present the mechanisms leading to MBR emission in EAS, the status of the current radio-detection setups using this technique, and the prospects to improve their sensitivity.