H. Stiele, T. Muñoz-Darias, S. Motta, T. M. Belloni
We report on a spectral-timing analysis of the black hole X-ray binary
candidate MAXI J1543- 564 during its 2011 outburst. All 99 pointed observations
of this outburst obtained with the Rossi X-ray Timing Explorer (RXTE) were
included in our study. We computed the fundamental diagrams commonly used to
study black hole transients, and fitted power density and energy spectra to
study the spectral and timing parameters along the outburst. The determination
of timing parameters and hence of exact transitions between different states
was hampered by the rather low count rate at which his outburst was observed.
We detected two periods of exponential decay, one after the source was
brightest, which was interrupted by several flares, and another one during the
high/soft state. The detection of these decays allowed us to obtain an estimate
for the source distance of at least 8.5 kpc. This leaves two possible
explanations for the observed low count rate; either the source has a distance
similar to that of other black hole X-ray binary candidates and it is
intrinsically faint, or it has a similar luminosity, but is located more than
12 kpc away from us. Furthermore, in the high/soft state the source spectrum
appears to be completely disc dominated.
View original:
http://arxiv.org/abs/1201.5895
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