Title: High-energy studies of Microquasars: spectropolarimetry with INTEGRAL and preliminary results from SVOM
Place: CEA – Orme des Merisiers, building 703 (Ground floor Amphitheater / room 45)
Abstract: Black Hole X-ray Binaries are binary systems where a stellar-mass Black Hole accretes material from a companion star, leading to X-ray to gamma-ray emission attributed to heat dissipation in the accretion disk and inverse Compton radiation from a corona. Above the typical spectral cut-off of the Compton component, strong hard X-ray emission was also detected in several sources. Known as the hard-tail, it was interpreted as either non-thermal inverse Compton emission, or synchrotron emission, or a mix of both. These objects are also found to have powerful bipolar jets similarly to Quasars, resulting in the name Microquasar as their scaled down version. The hard-tail emission could be linked to these accretion-ejection processes.
Although challenging to measure properly, spectro-polarization is a critical tool to understand and distinguish the precise emission mechanisms, as it provides novel diagnosis to constrain parameters related to source geometry and magnetic fields. In particular, the INTEGRAL satellite and the newly launched French-Chinese SVOM satellite are well fitted to achieved those goals.
Supervisors: RODRIGUEZ-VACHOUX Jerôme, LAURENT Philippe
Jury members: MARCOWITH Alexandre, BOUCHET Laurent, HANLON Lorraine, KIERANS Carolyn, PETRUCCI Pierre-Olivier, TATISCHEFF Vincent, CANGEMI Floriane (invitée)