Title：Radiation pressure dominated disks in accreting X-ray pulsars  

　　Speaker：纪龙(德国Tuebingen大学博士后)  

　　Abstract：X-ray pulsars are highly magnetized neutron stars in binary systems with B ~ 10^12G, fed by accretion of matter from a donor star. The accretion matters lose their angular momentum via the viscosity effect and form a Shakura-Sunyaev accretion disk. The accretion disk is believed to be dominated by gas and radiation pressures in the outer and inner regions, respectively. In accreting X-ray pulsars, due to the strong magnetic field, the accretion disk is generally truncated at a distance far away from the pulsar, which is in a gas pressure dominated regime. However recently the presence of the radiation pressure dominated disk is proposed in some sources via different methods. In this talk, I would like to introduce the accretion processes in X-ray pulsars and represent state-of-the-art observational clues of radiation pressure dominated disks.  

紫金山天文台学术委员会