|
| | | | |
| | | |
| Stat |
Members: 3645
Articles: 2'506'133
Articles rated: 2609
27 April 2024 |
|
| | | | |
|
Article overview
| |
|
|
The Properties of X-Ray and Optical Light Curves of X-Ray Novae | | Wan Chen
; C.R. Shrader
; Mario Livio
; | | Date: |
12 Jul 1997 | | Subject: | astro-ph | | Affiliation: | Univ. of Maryland & NASA/GSFC), C.R. Shrader (USRA & NASA/GSFC), Mario Livio (STScI | | Abstract: | We have collected the available data from the literature and from public data archives covering the past two decades for the long-term X-ray and optical light curves of X-ray nova (XN) outbursts, and carry out for the first time a systematic, statistical study of XN light curves which are classified into 5 morphological types. Basic light curve parameters, e.g., the outburst peak flux, amplitude, luminosity, rise and decay timescales, the observed and expected outburst durations, and total energy radiated, are tabulated and discussed. The rise timescales are found to have a flat distribution while the decay timescales have a much narrower and near-Gaussian distribution, centered around 30 days and dominated by the strongest outbursts. The peak luminosity is also distributed like a Gaussian, centered around 0.2 in Eddington units, while the total energy released has a much broader distribution around 10E44 ergs. We identify and discuss additional light curve features, such as precursors, plateaus, and secondary maxima. The plateaus exhibited in the light curves of black hole sources are found to have, on average, longer durations and they are followed by longer decays. The identified secondary maxima seem to occur mostly in black hole systems. For the frequency of outbursts, we find that the average XN outburst rate is about 2.6 per year for events >0.3 Crab, and that the mean recurrence time between outbursts from a single source is 6 years. The spatial and logN-logS distribution of the XN sources, with limited statistics, agrees with a source population in the Galactic disk, as observed from a point at a distance of 8.5 kpc from the Galactic center. Finally, we point out that the observed XN light curve properties can in general be explained by a disk thermal instability model, although some important problems still remain. | | Source: | arXiv, astro-ph/9707138 | | Services: | Forum | Review | PDF | Favorites | |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
|
| |
|
|
|
|
News, job offers and information for researchers and scientists:
| |
REGISTER