GCN Circular 43809
Subject
Fermi GRB 260223A: Global MASTER-Net observations report
Event
Date
2026-02-23T05:15:25Z (2 days 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, I. Gorbunov (Lomonosov MSU),
O.Gress, N.Budnev (ISU),
C.Francile, F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A.Sosnovskij (CrAO),
A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity),
D.Buckley (SAAO),
R.Rebolo (The Instituto de Astrofisica de Canarias),
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory)
MASTER-OAFA robotic telescope [1] located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 260223A ( Fermi GBM team, GCN 43808) errorbox 123 sec after notice time and 154 sec after trigger time at 2026-02-23 04:13:44 UT, with upper limit up to 19.8 mag. The observations began at zenith distance = 32 deg. The sun altitude is -48.2 deg.
The galactic latitude b = -7 deg., longitude l = 243 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=3152151
We obtain a following upper limits.
Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
170 | 2026-02-23 04:13:44 | MASTER-OAFA | (07h 21m 14.73s , -29d 00m 58.9s) | C | 30 | 19.3 |
210 | 2026-02-23 04:14:20 | MASTER-OAFA | (07h 21m 14.73s , -29d 00m 58.0s) | C | 40 | 19.5 |
262 | 2026-02-23 04:15:07 | MASTER-OAFA | (07h 21m 14.77s , -29d 00m 57.4s) | C | 50 | 19.6 |
324 | 2026-02-23 04:16:03 | MASTER-OAFA | (07h 21m 14.79s , -29d 00m 56.9s) | C | 60 | 18.9 |
395 | 2026-02-23 04:17:09 | MASTER-OAFA | (07h 21m 14.83s , -29d 00m 56.3s) | C | 70 | 19.8 |
603 | 2026-02-23 04:20:17 | MASTER-OAFA | (07h 22m 38.12s , -29d 04m 33.0s) | C | 110 | 19.3 |
730 | 2026-02-23 04:22:15 | MASTER-OAFA | (07h 22m 38.17s , -29d 04m 33.2s) | C | 130 | 19.4 |
882 | 2026-02-23 04:24:31 | MASTER-OAFA | (07h 22m 38.28s , -29d 04m 33.1s) | C | 160 | 19.5 |
998 | 2026-02-23 04:27:17 | MASTER-OAFA | (07h 22m 38.38s , -29d 04m 32.8s) | C | 60 | 18.9 |
1063 | 2026-02-23 04:28:23 | MASTER-OAFA | (07h 22m 38.43s , -29d 04m 32.7s) | C | 60 | 19.2 |
1129 | 2026-02-23 04:29:29 | MASTER-OAFA | (07h 22m 38.49s , -29d 04m 32.7s) | C | 60 | 19.1 |
1196 | 2026-02-23 04:30:35 | MASTER-OAFA | (07h 22m 38.53s , -29d 04m 32.7s) | C | 60 | 19.1 |
1261 | 2026-02-23 04:31:40 | MASTER-OAFA | (07h 22m 38.57s , -29d 04m 32.8s) | C | 60 | 18.9 |
1326 | 2026-02-23 04:32:46 | MASTER-OAFA | (07h 22m 38.61s , -29d 04m 33.1s) | C | 60 | 18.9 |
1393 | 2026-02-23 04:33:52 | MASTER-OAFA | (07h 22m 38.66s , -29d 04m 33.1s) | C | 60 | 19.0 |
1458 | 2026-02-23 04:34:58 | MASTER-OAFA | (07h 22m 38.71s , -29d 04m 33.0s) | C | 60 | 18.8 |
1524 | 2026-02-23 04:36:04 | MASTER-OAFA | (07h 22m 38.76s , -29d 04m 33.3s) | C | 60 | 19.2 |
1591 | 2026-02-23 04:37:10 | MASTER-OAFA | (07h 22m 38.81s , -29d 04m 33.5s) | C | 60 | 19.2 |
1656 | 2026-02-23 04:38:15 | MASTER-OAFA | (07h 22m 38.85s , -29d 04m 33.5s) | C | 60 | 19.2 |
1721 | 2026-02-23 04:39:21 | MASTER-OAFA | (07h 22m 38.89s , -29d 04m 33.7s) | C | 60 | 19.1 |
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