Gamma-Ray Bursts are short lived (0.1-100 s) gamma-ray transient sources that appear randomly on the entire sky. Even if they have been discovered at the end of the 1960s, their nature remained mysterious until the end of the 1990s. It is only thanks to the observations of the BeppoSAX satellite at the end of the last century and especially thanks to the observations of the Swift satellite starting from 2004, that the mysterious nature of GRBs started to be elucidated.
These emissions are related to the final stages of very massive stars (30-50 times the mass of the Sun) for the long GRBs (<2 s) or to the merger of two compact objects (typically two neutron stars) for the short GRBs (< 2s). In either case there is the creation of a powerful relativistic jet, which is at the origin of the electromagnetic emission that is measure in gamma-rays and in other energy bands. If this jet points towards the Earth, GRBs can be detected up to very long distances (z~9.1) corresponding to a young age of the Universe (~500 Myr).
Svom is a sino-french space mission dedicated to GRBs, which has been successfully launched on June 22nd 2024, and in which CEA/Irfu/DAp is deeply involved. The PHD subject is aimed at exploiting the multi-wavelength data of SVOM and its partner telescopes in order to investigate the nature of GRBs, and in particular to make use of X-ray data from the MXT telescope in order to try to constrain the nature of the compact object which is at the origin of the relativistic jets.