[vsnet-grb-info 21465] GRB 181225A: Global MASTER Net optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  23564
SUBJECT: GRB 181225A: Global MASTER Net optical observations 
DATE:    18/12/26 11:36:28 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov at xray.sai.msu.ru>

D.Kobtsev, V. Yurkov, A. Gabovich, Yu. Sergienko,
(Blagoveschensk State Pedagogical University, Russia)

V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina,  P.Balanutsa, A.Kuznetsov, D. Vlasenko,
(Lomonosov Moscow State University, SAI)

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

D. Buckley (South African Astronomical Observatory)

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

O. Gres, N.M. Budnev, S. Yazev, O. Chuvalaev (API, Irkutsk State University)

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

H. Levato
(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio of San 
Juan National University, Argentina)


Global MASTER-Net (http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)
was pointed to LAT GRB 181225A (Arimoto et al. GCN 23561, first detected by AGILE in GCN 23560 Ursi et al. )
by MASTER-SAAO (at 2018-12-25 21:08:21UT, alert_altitude=9deg.) and by 
MASTER-IAC.

MASTER-IAC robotic telescope, located in Spain (IAC Teide Observatory), 
was pointed to the LAT GRB181225.49 ( 23h 12m 16.80s , -09d 28m 48.00s, R=0.13)
34022 sec after trigger time at 2018-12-25 21:11:14 UT, with upper limit up to 19.9 mag.

We didn't find OT brighter 19.9 (unfiltered).

The observations started at zenit distance = 60 deg. The sun altitude was -38.0 deg.
The galactic latitude b = -60 deg., longitude l = 98 deg.

Updated in real-time cover map and discovered OT will be  available here:
https://master.sai.msu.ru/site/master2/observ.php?id=893244

The observation and reduction will be continued.

The message may be cited.