PSN J13101968+3228257 prediscovery observations by MASTER
ATel #4762; D. Denisenko, V. Lipunov, E. Gorbovskoy, N. Tiurina, V. Kornilov, A. Belinski, N. Shatskiy, V. Chazov, A. Kuznetsov, 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. Balanutsa, S. Shurpakov, V. Shumkov, V. Yecheistov, P. Podvorotny (MASTER team members), H. Levato, C. Saffe (ICATE), C. Mallamaci, C. Lopez and F. Podest (Observatorio Astronomico Felix Aguilar; OAFA)
on 25 Jan 2013; 16:17 UT
Credential Certification: Vladimir Lipunov (lipunov2007@gmail.com)
Following the posting on CBAT TOCP of PSN J13101968+3228257 in UGC 8250 (unfiltered magnitude 17.0 on 2013 Jan. 22.36) we have checked the archival observations of this field by MASTER-II robotic telescopes (0.4-m f/2.5 reflectors with 4kx4k CCDs). The object is clearly visible on six MASTER-Kislovodsk survey images of 2012 Dec. 07.096-07.128 UT (unfiltered magnitude 15.02+/-0.03) and on 10 MASTER-Amur images obtained on 5 different nights from 2012 Nov. 30 to 2013 Jan. 19. Coordinates measured by the robot are: R.A.=13h10m19.64s, Dec.=+32o28'25.4" which is 6"W and 33"S of the center of host galaxy. The automatic photometry from MASTER-Amur images (60-sec exposures) with reference to (0.8R+0.2B) magnitudes from USNO-B1.0 is presented in Table below.
| Obs. time (UT) | Mag. | Err. |
| 2012-11-30 21:41:08 | 15.86 | 0.14 |
| 2012-12-14 17:47:44 | 14.82 | 0.07 |
| 2012-12-14 18:34:04 | 14.83 | 0.07 |
| 2012-12-21 18:02:09 | 15.12 | 0.06 |
| 2012-12-21 18:48:31 | 15.06 | 0.05 |
| 2012-12-25 17:56:16 | 15.50 | 0.11 |
| 2012-12-25 18:41:32 | 15.31 | 0.09 |
| 2013-01-19 18:51:39 | 16.90 | 0.17 |
| 2013-01-19 19:37:57 | 16.78 | 0.17 |
| 2013-01-19 19:37:57 | 17.02 | 0.16 |
We have the latest pre-outburst image without PSN on 2012-11-22.856 UT with limiting magnitude 18.3. The comparison of MASTER-Amur images on 2012 Nov. 22 (pre-outburst) and Dec. 14 (maximum brightness) is uploaded to http://master.sai.msu.ru/static/OT/131019.65322825.0.png
MASTER-Amur light curve of PSN J13101968+3228257 is posted at http://master.sai.msu.ru/static/OT/PSNJ13101968+3228257-MASTER-Amur.gif and is consistent with that of SN Ia with the maximum (14.8U) near 2012 Dec. 14.
Global MASTER Robotic Net
