TITLE:   GCN CIRCULAR
NUMBER:  42769
SUBJECT: GRB 251018A: FRAM-Auger optical detection
DATE:    25/11/19 20:02:40 GMT
FROM:    Martin Jelinek at Astro.Inst-AVCR,Ondrejov <martin.jelinek@asu.cas.cz>

Anurag Talele (University of Potsdam),

Martin Jelinek, Alzbeta Malenakova, Jan Strobl 
(ASU CAS Ondrejov, CZ), 

Filip Novotny (ASU Ondrejov + Masaryk University),

Martin Masek, Petr Janecek, Sergey Karpov, Jakub Jurysek, 
Jan Ebr, Ronan Cunniffe, Petr Travnicek and Michael Prouza
(Institute of Physics, Prague, CZ)

report:

The 30 cm robotic telescope at the FRAM-Auger in
Malargue (Argentina) reacted robotically to the
Swift/BAT alert of GRB251018A (trigger 1405083, Gupta
et. al. GCN42343) issued at 03:12:02 UT.

FRAM obtained its first unfiltered exposure 42 seconds
after the trigger, at 03:12:44 UT, followed by a
sequence of 20s and 60s exposures.

An optical transient is detected at the UVOT position.
It appears at R(Vega) roughly 15.5 mag at T0 + 78s and
fades to roughly 18.0 mag by the end of our 28 minutes
observing run consistent with detections by Lipunov et.
al. GCN42346, Hu et. al. GCN42363 and Kuin et. al.
GCN42353.