Optical counterpart of MAXI J1348-630

ATel #12430; D. Denisenko (Education Center on Donskaya, Moscow; SAI MSU), I. Denisenko, M. Evtushenko, D. Fernandez OrtiZ, I. Kotelnikov, M. Komarov, I. Larin, I. Spasic, D. Vdovin (Education Center on Donskaya, Moscow)
on 26 Jan 2019; 17:33 UT
Credential Certification: Denis Denisenko (d.v.denisenko@gmail.com)

Tweet

We have observed error box of new X-ray transient MAXI J1348-630 (F. Yatabe et al., ATel #12425) with iTelescope.Net T31 instrument (0.51-m f/6.8 reflector + CCD) in Siding Spring, Australia. A series of unfiltered 60-sec exposures was taken at 16:09-16:14 UT on 2019 Jan. 26 with the T31 field of view (0.93x0.93 degree) covering the entire 90% confidence level uncertainty area. The combined images were compared to the scanned DSS Red plates taken on 1994-03-10, 1994-08-12, 1997-03-31 and 1999-02-16. The only object that stands out in the inspected field is the new optical transient at the following position (J2000.0): R.A. = 13 48 12.88, Decl. = -63 16 28.4. The magnitude of the object (unfiltered with the red zero point) at 2019-01-26.675 UT is 16.18 measured using 2MASS J13480967-6315325 as reference star with V=14.43 in APASS DR9 (A. Henden et al., 2016).

T31 discovery image is posted at http://scan.sai.msu.ru/~denis/J1348-630-T31-20190126.jpg

The new OT is within Swift error circle (V. D'Elia et al., GCN #23796), 82 arc sec from its center. There is no known variable star at this position in AAVSO VSX and GCVS. The nearest star in Gaia DR2 is 1.6 arc sec away with Gmag=21.13. Precise astrometry, spectroscopy and photometric time series of the new OT are strongly encouraged.