Astrophysique à Haute Energie

More than one century after their discovery, the origin of cosmic rays remains one of the most important open questions in astrophysics. They are detected as a flux of charged particles, mainly protons and light nuclei, reaching extremely high energies (up to around 10^20 eV). The detection of cosmic rays implies the existence of efficient particle accelerators in the Universe.

Cosmic rays are energetic particles that reach the Earth from outer space. Most cosmic rays are accelerated within our Galaxy, and remain trapped in the Galactic magnetic field for about 10 million years before escaping in the intergalactic space.