[ Previous | Next ]
ATEL # 1414; F. Capitanio, M. Del Santo & A. Bazzano (INAF/IASF-Roma)
on 6 Mar 2008; 18:01 UT
Password Certification: Melania Del Santo (firstname.lastname@example.org)
Subjects: X-ray, Binaries, Black Holes, Transients
We followed the BHC H1743-322/IGR J17464-3213 (ATels #1348,#1349,#1352) with Swift/XRT during the decreasing phase of the outburst until quiescence for a total amount of 20 ks (in 6 pointings). The observations were performed two times per week from 2008 February 12th at 01:31:00 UT until March 5 13:19:18 UT. The source flux decreasing along the observing period occurred with a constant spectral shape, namely an absorbed power-law. The best fit parameters of all pointings are consistent within the errors with the first observation, i. e. gamma=1.8 +/- 0.2 and Nh=2.4+/-0.3 cm-2 (ATel #1387). On 2008 February 26th 01:17:50 UT (latest detection) the unabsorbed flux between 2-10 keV (8.0E-12 erg cm-2 s-1) was two orders of magnitude lower than in the first pointing (ATel #1387). Thereafter on March 4 13:19:18 UT the source flux was at the Swift/XRT detection limit. The 2 sigma level upper limit flux was estimated in 3.4E-14 erg cm-2 s-1 which translates in a luminosity of about 3 E+32 erg s-1 (at 8 kpc). We would like to thank N. Gehrels and the whole Swift Team for their support.