Supergiant Fast X-ray Transients observed by INTEGRAL

Abstract

We review X-ray properties of the Supergiant Fast X-ray Transients following from their observations with INTEGRAL and show that a compact object in these systems is a neutron star with strong magnetic field accreting from the stellar wind of a donor star. We show that presence of a centrifugal barrier at the magnetospheric boundary of the neutron star may be a key to understanding of abrupt short X-ray outbursts of these transients and long intervals of their quiescence.