MASTER OT J045237.07+851925.2 - bright optical counterpart of Fermi LAT/GBM GRB211023A
ATel #14996; K. Zhirkov, V. Lipunov, E. Gorbovskoy, P. Balanutsa, A. Kuznetsov, O. Gress, G. Antipov, D. Vlasenko, N. Tiurina, D. Zimnukhov, V. Senik, V. Topolev, A. Chasovnikov, E. Minkina, V. Grinshpun, D. Cheryasov (Lomonosov MSU), R. Rebolo, M. Serra(IAC), D. A.H. Buckley (SAAO), O. A. Gres, N. M. Budnev (ISU, API), R. Podesta, C. Lopez, F. Podesta, C. Francile (OAFA), A. Tlatov, D. Dormidontov (KSS, Pulkovo observatory), A. Gabovich, V. Yurkov (BSPU)
on 24 Oct 2021; 20:59 UT
Credential Certification: Nataly Tyurina (tiurina@sai.msu.ru)
Subjects: Optical, Gamma Ray, Request for Observations, Gamma-Ray Burst, Transient, Variables
MASTER OT J045237.07+851925.2 discovery - optical counterpart of Fermi LAT/GBM GRB 211023A
MASTER Global robotic net (http://observ.pereplet.ru Lipunov et al.,2010,Advances in Astronomy,2010,30L)
started FERMI GRB 211023A ( Fermi GBM team, GCN #30958, Ttrigger=13:05:43, Fermi LAT GCN #30961) errorbox inspect just after sunset at 2021-10-23 15:12:50 UT (Lipunov et al. GCN #30970 https://master.sai.msu.ru/site/master2/event.php?id=1762531).
MASTER-Kislovodsk auto-detection system ( Lipunov et al., "MASTER Global Robotic Net", Advances in Astronomy, 2010, 30L )
discovered OT source - changing optical counterpart of this GRB
at (RA, Dec) = 04h 52m 37.07s +85d 19m 25.2s at 2021-10-23.65385 UT.
OT unfiltered magnitude at one of first images is 15.6m (mlim=18.9).
There is no minor planet in MPC and no any known sources in VIZIER at this place.
We have reference image on 2017-01-28.75669 UT with unfiltered mlim=19.9m.
Deep images and possibly host galaxy spectral observations are required.
MASTER Global Robotic Net
