Phase-resolved optical and X-ray spectroscopy of low-mass X-ray binary X1822-371

The X1822-371 is the prototypical accretion disc corona X-ray source, a low-mass X-ray binary viewed at very high inclination, thereby allowing the disc structure and extended disc coronal regions to be visible. As the brightest such source, X1822-371 is ideal for studying the shape and edge structure of an accretion disc, and comparing with detailed models. The authors study the structure of the accretion disc in X1822-371 by modelling the phase-resolved spectra both in optical and X-ray regime. They analyse high time resolution optical ESO/VLT spectra of X1822-371 to study the variability in the emission line profiles. In addition, they use data from XMM-Newton space observatory to study phase-resolved as well as high resolution X-ray spectra. They find that their results from both the optical and X-ray analysis can be explained with a model where the accretion disc has a thick rim in the region where the accretion stream impacts the disc.