The 2009 outburst of H~1743-322 as observed by RXTE

Abstract

We analyze the RXTE observations of the 2009 outburst of H~1743-322, as well as the observations of the previous five outbursts for comparison. The hardness-intensity diagram (HID) shows a complete counter-clockwise q-track for the 2009 outburst and, interestingly, the track falls in} between a huge one in 2003, with a complete transition to high/soft state, and that of} the failed outburst in 2008. It leaves the low/hard state but does not reach the leftmost edge of the overall HID. While the lowest hardness (6--19 keV/3--6 keV) values} in the HID is about 0.3--0.4 for the 2009 outburst, similar to the ``failed state transition" seen in the persistent black hole XRB Cyg X-1, the timing analysis shows that a transition to the high soft state occurred. During the low/hard state of the 2009 outburst, the inner radius of the accretion disk is found to be closer to the central black hole and have an anti-correlation with the disk temperature. These results may be understood as the reprocessing} of the hot corona on the disk's} soft X-rays, which can lead to an underestimation of the inner radius of the accretion disk. In the luminosity diagram of the corona versus the disk, the tracks of the outbursts} in 2003 and 2009 cross the line which represents a roughly equal contribution to the entire emission from the thermal and the non-thermal components;} the track of the 2008 outburst has the turn-over falling} on this line. This may be indicative of an emission balance between the corona and the disk, which prevents the state transition from going further than the low/hard state.