Ekaterina Sokolova-Lapa (Astronomisches Institut der Universität Erlangen-Nürnberg)
The accretion powered X-ray pulsars are one of the brightest X-ray sources of our galaxy. Despite the long period of research, we still do not have a self consistent model for the emerging radiation that would describe the spectral energy distribution of these sources. Often, only phenomenological models are used for investigation. The reason for this is partly due to the computational difficulties involved in analytical and numerical modeling, partly still due to some lack of understanding of the physical processes in such extreme conditions. The X-ray radiation during accretion onto the magnetized neutron star originates from regions with very high temperature and strong magnetic fields which makes the propagation of the radiation highly anisotropic. The radiation is strongly polarized due to magnetized plasma effects and vacuum birefringence. In this talk, I will introduce accreting neutron stars and outline the main difficulties encountered in modeling the spectral formation process, with the focus on low accretion rate case when the accreting matter stops to the rest in the neutron star atmosphere.
Paweł Haensel (CAMK, Warsaw)
The talk is based on the recent work of I. Tews, J. Margueron and S. Reddy: https://arxiv.org/abs/1901.09874
