Gamma-ray bursts afterglow physics and the VHE domain

Understand

Afterglow radiation in gamma-ray bursts (GRB), extending from the radio band to GeV energies, is produced as a result of the interaction between the relativistic jet and the ambient medium.

• Although in general the origin of the emission is robustly identified as synchrotron radiation from the shock-accelerated electrons, many aspects remain poorly constrained, such as the role of inverse Compton emission, the particle acceleration mechanism, the properties of the environment and of the GRB jet itself.
• The extension of the afterglow emission into the TeV band has been discussed and theorized for years, but has eluded for a long time the observations.
• Recently the Cherenkov telescopes MAGIC and H.E.S.S.