The Transient 42 Second X-Ray Pulsar EXO 2030+375. I. The Discovery and the Luminosity Dependence of the Pulse Period Variations
Stella, L.; Parmar, A. N.; White, N. E.; Ferri, P.; Izzo, C.
Netherlands
Abstract
The discovery of a new transient X-ray pulsar, EXO 2030+375, that is associated with a Be star companion, is reported. The results of a series of EXOSAT observations, where the evolution of the pulsar's properties over two orders of magnitude in luminosity was monitored. The dependence of the change in pulsar period on luminosity is measured and compared with that predicted by accretion torque theory. The pulsar properties are also compared with those of other transient X-ray pulsars.