Samia Drappeau (U. of Amsterdam)
Jeudi 22 Novembre - 11 h 00
Salle Manuel Forestini - IPAG
X-ray binaries (XRBs) are binary systems in which a compact object (neutron star or black hole) accretes matter from a companion star. The accretion processes onto a compact object emit strongly in the X-ray band, making XRBs the brightest sources of X-rays in our galaxy. Also associated with XRBs is radio emission from both discrete ejecta as well as collimated, compact jets. The jets are relativistic outflows launched from the vicinity of the compact object and are believed to be powerful particle accelerators. As a consequence of the intense studies of XRBs from the radio through X-ray bands over the past decades, we can characterize properties such as distinct accretion states, and the disk/jet connection via correlations such as that observed between the radio/IR and X-rays. In the last few years, the rapid development of gamma-ray observations has open a new window on these sources, with at least one solid detection so far. Associated with these gamma-ray are neutrino emission. In this talk we present a new lepto-hadronic model that is based on successful work fitting the lower energy, broadband spectra of XRBs in the compact jet-dominated state. Protons (and electrons) are accelerated throughout the jet and cool via radiation and inelastic collisions, and we calculate spectral energy distributions (SEDs) including both hadronic and leptonic induced processes. We present new predictions for the gamma-ray fluxes in the GeV-TeV range. Moreover we will discuss neutrino flux prediction from the model, in particular assessing whether these sources will be visible to the planned KM3NET. This model can also be scaled to describe the SEDs of low-luminosity active galactic nuclei (LLAGN) such as our own Galactic Center black hole Sgr A*.
Dans la même rubrique :