Disappearing Pulses in Vela X-1
Astrophysics
2009-10-31 v1
Abstract
We present results from a 20 h RXTE observation of Vela X-1, ncluding a peculiar low state of a few hours duration, during which the pulsation of the X-ray emission ceased, while significant non-pulsed emission remained. This ``quiescent state'' was preceded by a ``normal state'' without any unusual signs and followed by a ``high state'' of several hours of increased activity with strong, flaring pulsations. while there is clear spectral evolution from the normal state to the low state, the spectra of the following high state are surprisingly similar to those of the low state.
Cite
@article{arxiv.astro-ph/9910539,
title = {Disappearing Pulses in Vela X-1},
author = {P. Kretschmar and I. Kreykenbohm and J. Wilms and R. Staubert and W. A. Heindl and D. E. Gruber and R. E. Rothschild},
journal= {arXiv preprint arXiv:astro-ph/9910539},
year = {2009}
}
Comments
5 pages, 5 figures, Proceedings of the 5th Compton Symposium, AIP, in press