Following the 2008 outburst decay of the black hole candidate H 1743-322 in x-ray and radio
Jonker, P. G., Miller-Jones, J., Homan, J., Gallo, E., Rupen, M., Tomsick, J., Fender, R. P., Kaaret, P., Steeghs, D. (Danny), 1972-, Torres, M. A. P., Wijnands, R., Markoff, S. and Lewin, W. H. G.. (2010) Following the 2008 outburst decay of the black hole candidate H 1743-322 in x-ray and radio. Monthly Notices of the Royal Astronomical Society, Vol.401 (No.2). pp. 1255-1263. ISSN 0035-8711Full text not available from this repository.
Official URL: http://dx.doi.org/10.1111/j.1365-2966.2009.15717.x
In this paper, we report on radio (Very Large Array and Austrialian Telescope Compact Array) and X-ray (RXTE, Chandra and Swift) observations of the outburst decay of the transient black hole candidate H 1743-322 in early 2008. We find that the X-ray light curve followed an exponential decay, levelling off towards its quiescent level. The exponential decay time-scale is approximate to 4 days and the quiescent flux corresponds to a luminosity of 3 x 10(32)(d/7.5kpc)(2)erg s(-1). This together with the relation between quiescent X-ray luminosity and orbital period reported in the literature suggests that H 1743-322 has an orbital period longer than approximate to 10 h. Both the radio and X-ray light curve show evidence for flares. The radio-X-ray correlation can be well described by a power-law with index approximate to 0.18. This is much lower than the index of approximate to 0.6-0.7 found for the decay of several black hole transients before. The radio spectral index measured during one of the radio flares while the source is in the low-hard state is -0.5 +/- 0.15, which indicates that the radio emission is optically thin. This is unlike what has been found before in black hole sources in the low-hard state. We attribute the radio flares and the low index for the radio-X-ray correlation to the presence of shocks downstream the jet flow, triggered by ejection events earlier in the outburst. We find no evidence for a change in X-ray power-law spectral index during the decay, although the relatively high extinction of N-H approximate to 2.3 x 10(22) cm(-2) limits the detected number of soft photons and thus the accuracy of the spectral fits.
|Item Type:||Journal Article|
|Subjects:||Q Science > QB Astronomy|
|Divisions:||Faculty of Science > Physics|
|Journal or Publication Title:||Monthly Notices of the Royal Astronomical Society|
|Official Date:||11 January 2010|
|Number of Pages:||9|
|Page Range:||pp. 1255-1263|
|Access rights to Published version:||Restricted or Subscription Access|
|Funder:||Netherlands Organisation for Scientific Research, NASA, DTHS|
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