ART-XC Galactic Bulge survey - first results

ATel #13095; I. Mereminskiy, M. Pavlinsky, I. Lapshov, A. Lutovinov, S. Molkov, A. Semena, A. Shtykovsky, A. Tkachenko (IKI RAS) on behalf of ART-XC collaboration
on 9 Sep 2019; 20:42 UT
Credential Certification: Ilya Mereminskiy (i.a.mereminskiy@gmail.com)

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After completion of the initial calibration program, the ART-XC telescope on board the SRG observatory has started its performance verification program. The core part of this program is the Galactic Bulge Survey, which will cover a region of a few dozen square degrees, centered at l,b=(0,0) and elongated along the Galactic Plane.
During the first scanning observations performed on September 03-09, we detected the continued activity of two X-ray binaries located in this region (previously reported in June, ATel #12843):
the burster SAX J1750.8-2900 is registered up to ~25 keV with an estimated flux of 6.5x10^-11 erg/cm2/s in the 4-11 keV energy band,
the symbiotic binary XMMU J174445.5-295044 is fainter, with a flux of 2.0x10^-12 erg/cm2/s in the same energy band.
During the observation of the outer part of the Galactic bulge, ART-XC detected a previously unknown bright source in a field that was not previously covered with sensitive X-ray telescopes: SRGA J174956-34086 (where SRGA denotes that the source is discovered by SRG/ART-XC) has a flux of 2.7x10^-12 erg/cm2/s (4-11 keV).
We performed a short (1 ks) follow-up observation with Swift/XRT in order to improve its localization. The source is well detected in the 0.3-10 keV image and located at RA,Dec = 267.4854, -34.1459 (90% confidence radius is 4.3"). There are two bright stars in the VVV DR2 catalog (Minniti+, 2017) within this error box. Follow-up observations of SRGA J174956-34086 in other wavebands are encouraged.
ART-XC is an X-ray telescope on board the SRG observatory. The telescope is designed and built by IKI (Russian Academy of Sciences) and RFNC, with the participation from MSFC/NASA. The SRG observatory was launched from the Baikonur cosmodrome on 13 July 2019 by a Proton rocket and is now approaching the L2 point.
The ART-XC collaboration is grateful to the Swift team for the support and rapid scheduling of follow-up observations.