Bright outburst of X-ray source 2E 1756.8+1451 detected by MASTER
ATel #4970; D. Denisenko, V. Lipunov, E. Gorbovskoy, P. Balanutsa, N. Tiurina, V. Kornilov, A. Belinski, N. Shatskiy, V. Chazov, A. Kuznetsov, V. Yecheistov, D. Zimnukhov (Moscow State University, SAI), V. Krushinsky, I. Zalozhnih, A. Popov, A. Bourdanov, A. Punanova (Ural Federal University), K. Ivanov, S. Yazev, N. Budnev, E. Konstantinov, O. Chuvalaev, V. Poleshchuk, O. Gress, A. Frolova, (Irkutsk State University), A. Parkhomenko, A. Tlatov, D. Dormidontov, V. Senik (Kislovodsk solar station of the Pulkovo observatory RAS), V. Yurkov, Y. Sergienko, D. Varda, E. Sinyakov (Blagoveshchensk Educational University), P. Podvorotny, V. Shumkov, S. Shurpakov (MASTER team members), H. Levato, C. Saffe (ICATE), C. Mallamaci, C. Lopez and F. Podest (OAFA)
on 11 Apr 2013; 21:29 UT
Credential Certification: Vladimir Lipunov (firstname.lastname@example.org)
Subjects: Optical, X-ray, Cataclysmic Variable, Transient
MASTER OT J175908.60+145130.2 - new bright CV (outburst of 2E 1756.8+1451)
MASTER-Amur auto-detection system discovered OT source at (RA, Dec) = 17h 59m 08.60s +14d 51m 30.2s on 2013-04-11.75324 UT. The OT unfiltered magnitude is 14.2m (limit 18.4m). The OT is seen in 16 images. There is no minor planet at this place. We have reference image with OT at 17.4m on 2012-05-29.69487 UT (limit 18.6m). The object was also bright (14.1m) on two archival MASTER-Amur images obtained on 2011-04-17.685 and 17.721 UT.
The OT is identical to the star USNO-A2.0 0975-10134613 (17 59 08.66 +14 51 31.8 R=18.0 B=18.6) and
USNO-B1.0 1048-0310652 (17 59 08.598 +14 51 31.17 pmRA=-14 pmDE=-10 B1=18.57 R1=17.16 B2=19.08 R2=17.49 I=17.00). Color-combined (BRIR) finder chart is uploaded to http://master.sai.msu.ru/static/OT/J175908+145130-BRIR.jpg (10'x10' FOV).
The object is present in 2MASS catalog as 2MASS 17590860+1451309 (J=15.75+/-0.07, H=15.10+/-0.10, K=14.86+/-0.09). It also has an UV counterpart GALEX J175908.5+145130 (FUV=19.66+/-0.16, NUV=20.18+/-0.16). Finally, there is a previously unidentified X-ray source in EINSTEIN (HEAO 2) catalog 2E 1756.8+1451 (2E 3986) formally 15" away with the positional error 48" and X-ray flux 0.0218+/-0.0020 cnts/s.
There is nothing at this position in GCVS and AAVSO VSX. This area of sky in Hercules is not covered by SDSS and CRTS. No previous outbursts were detected on 9 digitized Palomar plates and on 48 NEAT images obtained on 18 different nights from 1997 Aug. 01 to 2005 Aug. 31.
Based on the presence of X-ray and UV counterparts, amplitude of variability and previous outburst detection we suggest that MASTER OT J175908.60+145130.2 is a new cataclysmic variable (dwarf nova). Follow up observations are required. The discovery and reference images are available at: http://master.sai.msu.ru/static/OT/175908.60145130.2.png
List of Optical Transients discovered by MASTER
Global MASTER Robotic Net