[Phys-seminars] 2018-05-22 Physics Colloquium

eichler eichler at bgu.ac.il
Sun May 13 22:18:19 IDT 2018

Physics Colloquium

 DATE: 22-05-18

 TIME: 15:30

 PLACE: Nanotechnology institute building (#51) room 15

On the Origin of Ultrahigh Energy Cosmic Rays

Dr. Noemie Globus, HU

Cosmic rays are one of the most fascinating, yet surprisingly common, phenomena in the universe. They consist of energetic particles with an out-of-equilibrium power-law spectrum extending over at least eleven orders of magnitude in energy, from ~1 GeV to 10^11 GeV. In the past few years, new measurements by experiments such as KASCADE- Grande, the Pierre Auger observatory and Telescope Array, have greatly improved our knowledge of the highest energy domain of the cosmic-ray spectrum. Recent Auger composition analyses suggest a composition getting gradually heavier above a few 10^18 eV. I review the recent observations and show that the observational data can be explained by a generic model having only one Galactic component and one extragalactic component. The key to the success of this model is that the protons emitted by the extragalactic sources have a different spectrum from the other types of nuclei, as we recently showed to be expected in highly magnetised and photon-r
 ich environments, such as the relativistic jets associated with GRB or AGN. I will discuss multi-messenger constrains brought by neutrino and gamma-ray experiments and discuss the possible extragalactic origin of the UHECR dipole anisotropy, recently reported by Auger.

More information about the Phys-seminars mailing list