INTEGRAL identified with SAX J1747.0-2853 a source of the X-ray outburst in the Galactic center region detected by MAXI

ATel #12578; I. A. Mereminskiy, S. A. Grebenev, R. A. Sunyaev (Space Research Institute, Moscow), E. Kuulkers (ESA/ESTEC, Noordwijk)
on 14 Mar 2019; 15:36 UT
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Credential Certification: Sergei Grebenev (sergei@hea.iki.rssi.ru)

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INTEGRAL observed the Galactic Center region on Feb. 12-16, Mar. 5-9 (PI: Grebenev) and Mar. 14, 2019 (PIs: Kuulkers, Sunyaev). This is the time when MAXI/GSC detected a strong outburst of a possible new X-ray transient in the Galactic Center region (tentatively named MAXI J1746-290, see ATEL #12576).

We have reconstructed the INTEGRAL/JEM-X mosaic images of the region in the 3-12 keV band using all the accumulated data to identify a source of the outburst. JEM-X has been used due to its good angular resolution (higher than that of IBIS - the other INTEGRAL telescope). There are no signs of new transient sources in the image, although there was significant activity detected from the well-known LMXB SAX J1747.0-2853 (=A 1743-288). The 3-12 keV flux from this source was equal to ~300 mCrab on Feb. 12, reached ~650 mCrab on Feb. 15-16, dropped to ~180 mCrab by Mar. 5-9 and then again raised to ~235 mCrab (on Mar. 14). The averaged flux in the mosaic image was ~340 mCrab. The data of Crab Nebula observations on Mar. 11 were used as a calibration source for these estimates.

There is another well-known source in the MAXI/GSC error circle, 1E 1743.1-2843 which is much fainter than SAX J1747.0-2853 (~34 mCrab). Both the sources are frequently observed with JEM-X, see, e.g. Grebenev, Mereminskiy, Astron. Lett. 41, 765 (2015).

INTEGRAL/JEM-X X-ray image of the Galactic Center field (Feb. 12 - Mar. 14, 2019)