GCN Circular 45799
Subject
Fermi GRB 261003A: Global MASTER-Net observations report
Event
Date
2026-10-03T02:45:49Z (6 hours ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
Via
email
V.Lipunov, E.Gorbovskoy, A.Kuznetsov, K.Zhirkov, I.Panchenko, N.Tiurina, P.Balanutsa, V.Topolev, D.Vlasenko,
G.Antipov, A.Sankovich, Yu.Tselik, Ya..Kechin, V.Senik, A.Chasovnikov, K.Labsina (Lomonosov MSU)
D.Buckley (SAAO),
A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity)
A.Sosnovskij (Lomonosov MSU)
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory)
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory)
R.Rebolo (The Instituto de Astrofisica de Canarias)
O.Gress, N.Budnev(ISU)
M. Segura, F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA)
MASTER-Tavrida robotic telescope [1] located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB 261003A ( Fermi GBM team, GCN 45797) errorbox 4620 sec after notice time and 4654 sec after trigger time at 2026-10-03 02:36:10 UT, with upper limit up to 16.5 mag. Observations started at twilight. The observations began at zenith distance = 80 deg. The sun altitude is -12.5 deg.
The galactic latitude b = 4 deg., longitude l = 83 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=3517714
We obtain a following upper limits.
Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
4660 | 2026-10-03 02:36:10 | MASTER-Tavrida | (19h 21m 38.90s , +53d 18m 43.8s) | C | 10 | 15.7 |
4673 | 2026-10-03 02:36:22 | MASTER-Tavrida | (19h 21m 38.98s , +53d 18m 43.0s) | C | 10 | 15.7 |
4673 | 2026-10-03 02:36:23 | MASTER-Tavrida | (19h 21m 33.52s , +53d 20m 03.7s) | C | 10 | 14.2 |
4687 | 2026-10-03 02:36:36 | MASTER-Tavrida | (19h 21m 39.10s , +53d 18m 43.1s) | C | 10 | 15.8 |
4687 | 2026-10-03 02:36:36 | MASTER-Tavrida | (19h 21m 33.60s , +53d 20m 04.4s) | C | 10 | 14.1 |
4705 | 2026-10-03 02:36:50 | MASTER-Tavrida | (19h 21m 39.22s , +53d 18m 43.0s) | C | 20 | 16.2 |
4706 | 2026-10-03 02:36:50 | MASTER-Tavrida | (19h 21m 33.74s , +53d 20m 04.6s) | C | 20 | 14.6 |
4729 | 2026-10-03 02:37:13 | MASTER-Tavrida | (19h 21m 39.35s , +53d 18m 43.2s) | C | 20 | 16.0 |
4756 | 2026-10-03 02:37:36 | MASTER-Tavrida | (19h 21m 39.48s , +53d 18m 43.1s) | C | 30 | 16.2 |
4756 | 2026-10-03 02:37:36 | MASTER-Tavrida | (19h 21m 33.97s , +53d 20m 05.5s) | C | 30 | 14.6 |
4790 | 2026-10-03 02:38:10 | MASTER-Tavrida | (19h 21m 39.60s , +53d 18m 43.8s) | C | 30 | 16.3 |
4790 | 2026-10-03 02:38:10 | MASTER-Tavrida | (19h 21m 34.10s , +53d 20m 06.4s) | C | 30 | 14.6 |
4829 | 2026-10-03 02:38:43 | MASTER-Tavrida | (19h 21m 39.63s , +53d 18m 44.3s) | C | 40 | 16.4 |
4829 | 2026-10-03 02:38:44 | MASTER-Tavrida | (19h 21m 34.15s , +53d 20m 07.0s) | C | 40 | 14.9 |
4878 | 2026-10-03 02:39:27 | MASTER-Tavrida | (19h 21m 39.67s , +53d 18m 45.2s) | C | 50 | 16.5 |
4878 | 2026-10-03 02:39:27 | MASTER-Tavrida | (19h 21m 34.17s , +53d 20m 08.5s) | C | 50 | 14.9 |
4937 | 2026-10-03 02:40:21 | MASTER-Tavrida | (19h 21m 39.72s , +53d 18m 46.8s) | C | 60 | 16.5 |
4937 | 2026-10-03 02:40:21 | MASTER-Tavrida | (19h 21m 34.22s , +53d 20m 10.4s) | C | 60 | 14.9 |
5007 | 2026-10-03 02:41:27 | MASTER-Tavrida | (19h 21m 39.75s , +53d 18m 48.6s) | C | 70 | 16.5 |
5007 | 2026-10-03 02:41:27 | MASTER-Tavrida | (19h 21m 34.25s , +53d 20m 12.4s) | C | 70 | 14.9 |
Filter C is a clear (unfiltred) band.
The observation and reduction will continue.
The message may be cited.
[1] - V.M. Lipunov, V.G. Kornilov, E.S. Gorbovskoy, N.A. Tiurina & A.S.Kuznetsov, 2023, Astronomical Robotic Networks and Operative Multichanel Astrophysics, Lomonosov MSU PRESS, 591pp.
http : // www.pereplet.ru/lipunov/625.html