INTEGRAL Galactic bulge monitoring observations (ATel #438) on UT 13 September 2015 18:50-22:32 reveal renewed X-ray activity from the low-mass X-ray binary transient and Type I X-ray burster SAX J1750.8-2900 (IAU Circ. #6597). The last outburst from this source was reported in 2011 (ATels #3170, 3181).
The JEM-X 3-10 keV and 10-25 keV fluxes during our observations are 32+/-3 mCrab and 16+/-6 mCrab respectively. A Type I X-ray burst from SAX J1750.8-2900 was detected during these observations, on UT 13 September 2015 20:51, with a peak flux of 2.3+/-0.2 Crab (3-25 keV) and a duration of 17 seconds.
The source is not detected with IBIS/ISGRI on September 13 with 3-sigma upper limits of about 5 and 8 mCrab in the 18-40 keV and 40-100 keV bands, respectively (12.6 ksec exposure).
Similar observations about 5 days earlier (on UT 8 September 2015 13:52-17:34; 12.6 ksec exposure) did not reveal the source with 3-sigma upper limits of 7 (3-10 keV) and 15 mCrab (10-25 keV).
We encourage further observations of SAX J1750.8-2900 at X-rays and other wavelengths.
|Publication date||15 Sep 2015|
|Publication status||Published - 15 Sep 2015|
|Series||The Astronomer's telegram|
- Neutron Star