Unusual Optical Transient in Orion detected by MASTER
ATel #6702; V. Vladimirov, D. Denisenko, V. Lipunov, E. Gorbovskoy, N. Tiurina, P. Balanutsa, V. Kornilov, N. Shatskiy, V. Chazov, A. Kuznetsov, E. Popova (Lomonosov Moscow State University, SAI), A. Tlatov, D. Dormidontov, V. Senik, A. Parkhomenko (Kislovodsk Solar Station of Pulkovo Observatory), V. Krushinsky, I. Zalozhnih, A. Popov, A. Bourdanov (Ural Federal University), K. Ivanov, S. Yazev, N. Budnev, E. Konstantinov, O. Chuvalaev, V. Poleshchuk, O. Gress (Irkutsk State University), V. Yurkov, A. Gabovich, Y. Sergienko, E. Sinyakov (Blagoveshchensk Educational University), V. Shumkov, S. Shurpakov (MASTER team members)
on 15 Nov 2014; 12:44 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)
Subjects: Optical, X-ray, Transient, Variables, Young Stellar Object
Referred to by ATel #: 6713
MASTER OT J053123.94+120051.5 - flare of X-ray source near Orion OB 2 association
MASTER-Kislovodsk auto-detection system discovered OT source at (RA, Dec) = 05h 31m 23.94s +12d 00m 51.5s on 2014-11-14.11406 UT. The OT unfiltered magnitude is 18.2m (limit 18.8m). The OT is seen in 2 images. There is no minor planet at this place. We have reference image without OT on 2011-10-29.01676 UT with unfiltered magnitude limit 20.0m.
The OT at quiescence is identical to the star USNO-B1.0 1020-0062195 (R1=18.70 B2=20.58 I=18.45) that is variable on the digitized Palomar plates. The large proper motion reported in USNO-B1.0 and PPMXL is not real. The object does not move significantly between 1951-1954 POSS-I and 1989-1998 POSS-II plates. Color-combined DSS finder chart is uploaded to http://master.sai.msu.ru/static/OT/J053123+120051-BRIR.jpg (10'x10' FOV). The object is located near Orion OB 2 association with several reflection nebulae and dark clouds within 10' distance. This area of sky in Orion is not covered by SDSS and GALEX. The object is not present in infrared and radio catalogs.
The OT has an X-ray counterpart 1SXPS J053124.1+120048 = 3XMM J053123.9+120051. The nature of the object is uncertain. Follow up multi-wavelength observations and spectroscopy are required. Checking the light curve in archival data is also encouraged. The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/053123.94120051.5.png
List of Optical Transients discovered by MASTER
Global MASTER Robotic Net
