INTEGRAL detects an X-ray burst from SAX J1747.0-2853 with no detectable persistent emission
ATel #1944; J. Chenevez, S. Brandt (National Space Institute, Denmark), E. Kuulkers (ESA/ESAC, Spain), V. Beckmann (ISDC, Switzerland), T. Bird (Southampton, UK), A. Domingo (LAEFF/INTA, Spain), K. Ebisawa (ISAS, Japan), P. Jonker (SRON, The Netherlands), P. Kretschmar (ESA/ESAC, Spain), C. Markwardt (GSFC, USA), T. Oosterbroek (ESA/ESTEC, The Netherlands), A. Paizis (INAF-IASF, Italy), D. Risquez (LAEFF/INTA, Spain), C. Sanchez-Fernandez (ESA/ESAC, Spain), S. Shaw (Southampton, UK), R. Wijnands (UvA, The Netherlands)
on 26 Feb 2009; 16:06 UT
Credential Certification: Jerome CHENEVEZ (jerome@dsri.dk)
Subjects: X-ray, Request for Observations, Binary, Neutron Star, Transient
A new season of observations for the INTEGRAL Galactic Bulge monitoring (see ATel #438) has started on 2009 Feb. 21st.
During the latest observation between 2009 Feb 25 13:21 and 17:02 (UT) a type I X-ray burst from SAX J1747.0-2853 (1A 1743-288, aka GX .2-0.2) was detected by JEM-X at UT 14:50:51 (MJD=54887.61865). The burst profile showed clear evidence of a photospheric radius expansion event and the peak flux reached 1.6 Crab (4.2x10-8 erg/cm2/s) in the 3-25 keV range. The total duration of the event was
about 20 s, which is quite typical for the X-ray bursts from this source (see, e.g., ATELS #256, #642, and #734).
No persistent emission from the source was otherwise detected by JEM-X with upper limits of 5 mCrab (8x10-11 erg/cm2/s) and 2 mCrab (2x10-11 erg/cm2/s) in the 3-10 kev and 10-25 keV energy bands, respectively. The upper limit for ISGRI (10-40 keV) is about 10 mCrab.
This burst could be the first indication of renewed activity from this recurrent neutron star transient. A new outburst, if it is confirmed, would indeed be consistent with previous observations showing a periodicity of about 185 days (see Atel #1228), and expected to reach a maximum around the end of April 2009.
We will observe the source again on 2009 March 03 as part of the INTEGRAL Galactic Bulge monitoring program.
Follow-up observations are encouraged.