Аннотация:MASTER OT J071404.52+550304.2 discovery in PGC020455 - short variable OT, preliminary optical counterpart of GRB190404.29
During FERMI trigger 576054086/GRB190404.29 inspection (07h 09m 04.08s,+55d 16m 01.20s, R=11.45deg. Ttrig=2019-04-04 07:01:21.93 UT)
MASTER-Tavrida auto-detection system (Global MASTER-Net http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy,vol. 2010, 30L)
discovered OT source at (RA, Dec) = 07h 14m 04.52s +55d 03m 04.2s on 2019-04-04.78094 UT (Lipunov et al. GCN #24058).
The OT unfiltered magnitude is 18.5 (limit 19.8m). There are only 2 images (MASTER inspect mode of large error-fields observations)at this night:
Date_UT, unfiltered_mag (W=0.2B+0.8R by USNO-B1 thousands field stars)
2019-04-04 18:36:58.335 18.5 +-0.2
2019-04-04 18:44:33.528 18.3 +-0.2
There is no OT in 24h: at 2019-04-05 19:02:36UT with mlim=19.8 (MASTER-Tavrida)
This OT is in 21.2W,55.1N from the center of bright (Btc=15mag) galaxy PGC020455.
We have also reference image (without OT) on 2017-08-03.00720 UT with unfiltered magnitude limit 19.6m.
Deep photometry and spectroscopy are required.
The discovery and reference images are available at http://observ.pereplet.ru/images/MASTEROTJ071404.52+550304.2.jpg
MASTER cover map of Fermi trigger inspection is
http://observ.pereplet.ru/images/MASTERGRB180404.29map.jpg
http://www.astronomerstelegram.org/?read=12637