[vsnet-grb-info 21959] Hard Fermi GRB1904204.29/TriggNum576054086: MASTER optical counterpart discovery near PGC020455

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  24058
SUBJECT: Hard Fermi GRB1904204.29/TriggNum576054086: MASTER optical counterpart discovery near PGC020455
DATE:    19/04/07 18:19:41 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov at xray.sai.msu.ru>

V. Lipunov, T.Pogrosheva, E. Gorbovskoy, N.Tyurina, V.Kornilov, 
D.Vlasenko, V.Vladimirov, D.Zimnukhov,
A.Kuznetsov, P.Balanutsa, I.Gorbunov, A. Chasovnikov, V.Topolev, D.Kuvshinov (Lomonosov 
Moscow State University, SAI, Physics Department),

R. Podesta, C. Lopez, C.Francile, F. Podesta (Observatorio Astronomico Felix Aguilar OAFA, San Juan National University),

H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE,SJNU)

R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres (The Instituto de Astrofisica de Canarias),

D. Buckley (South African Astronomical Observatory),

O. Gress, N.M. Budnev, O.Ershova (Applied Physics Institute, Irkutsk State University),

V. Yurkov, A. Gabovich, Yu. Sergienko, D. Kobcev (Blagoveschensk Educational State University),

A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov (Kislovodsk Solar  Station of the Pulkovo Observatory),

MASTER-Tavrida robotic telescope  (Global MASTER-Net http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy,vol. 2010, 30L)
  located in Russia (Lomonosov MSU, SAI Crimea astronomical station)
automatically was pointed to the  FERMI GRB190404.29
(trigger 576054086  07h 09m 04.08s , +55d 16m 01.20s, R=11.45 Ttrig=2019-04-04 07:01:21.93UT)
40918 sec after trigger time at 2019-04-04 18:23:19 UT, with upper limit up to  20.2 mag.
The observations started at zenit distance = 25deg. The sun  altitude  was -22.6 deg.

MASTER OT J071404.52+550304.2 discovery in PGC020455

MASTER-Tavrida auto-detection system discovered OT source
at (RA, Dec) = 07h 14m 04.52s +55d 03m 04.2s on 2019-04-04.78094 UT.
The OT unfiltered magnitude is 18.5 (limit 19.8m).
There is 15 mag (B) galaxy PGC020455 at 160 Mpc. OT offset is  21.2W 55.1N 
arcsec from PGC020455 center.

The OT is seen in 2 inspection images (there is no minor planet at this 
place):
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 at MASTER-Tavrida image 
with mlim=19.8.

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 is 
http://observ.pereplet.ru/images/MASTERGRB180404.29map/jpg

The message may be cited.