Statistical analysis of archival Vela X-1 data
Abstract
We present a detailed analysis of all archival INTEGRAL data of the accreting X-ray pulsar Vela X-1. We extracted lightcurves in several energy bands from 20 keV up to 60 keV. The lightcurves show that the source was found in very active as well as quiet states. During the active states several giant flares were detected. For these states spectra between 5 keV and 120 keV were obtained. The spectra of the active states were found to be significantly softer than those from the quiet states. We performed a statistical analysis of the flaring behavior. The resulting log-normal distribution of the intensity of Vela X-1 shows that the source spends most of the time at an average flux level of 300 mCrab but also that the distribution extends well up to more than 2.0 Crab.
Keywords
Cite
@article{arxiv.0903.0832,
title = {Statistical analysis of archival Vela X-1 data},
author = {Felix Fürst and Ingo Kreykenbohm and Jörn Wilms and Peter Kretschmar and Dmitry Klochkov and Andrea Santangelo and Rüdiger Staubert},
journal= {arXiv preprint arXiv:0903.0832},
year = {2010}
}
Comments
9 pages, 7 figures, Published as as PoS(Integral08)119 in the 7th INTEGRAL workshop - An INTEGRAL View of Compact Objects Proceedings