GCN Circular 44601

Subject
Fermi GRB 260512A: Global MASTER-Net observations report
Event
GRB 260512A
Date
2026-05-14T00:15:51Z (9 days ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
Via
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 260512A ( Fermi GBM team, GCN 44587Loading...
 
 ) errorbox  1 days 24421 sec after notice time and 1 days 24449 sec after trigger time at 2026-05-13 23:44:12 UT, with upper limit up to  19.9 mag. The observations began at zenith distance = 51 deg. The sun  altitude  is -24.8 deg. 

The galactic latitude b = -22 deg., longitude l = 298 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=3309891

We obtain a following upper limits.  

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

  110879 | 2026-05-13 23:44:12 |         MASTER-OAFA | (10h 10m 53.82s , -82d 11m 47.5s) |   C |    60 | 19.7 |        
  110939 | 2026-05-13 23:44:12 |         MASTER-OAFA | (10h 10m 53.83s , -82d 11m 47.6s) |   C |   180 | 19.9 |  Coadd 
  110955 | 2026-05-13 23:45:28 |         MASTER-OAFA | (10h 11m 00.56s , -82d 09m 55.3s) |   C |    60 | 19.7 |        
  111036 | 2026-05-13 23:46:49 |         MASTER-OAFA | (10h 10m 53.19s , -82d 10m 52.8s) |   C |    60 | 19.6 |        
  111114 | 2026-05-13 23:48:07 |         MASTER-OAFA | (10h 10m 56.57s , -82d 09m 54.2s) |   C |    60 | 19.6 |        
  111174 | 2026-05-13 23:48:07 |         MASTER-OAFA | (10h 10m 56.60s , -82d 09m 54.2s) |   C |   180 | 19.9 |  Coadd 
  111193 | 2026-05-13 23:49:26 |         MASTER-OAFA | (10h 11m 01.87s , -82d 10m 51.8s) |   C |    60 | 19.5 |        
  111266 | 2026-05-13 23:50:39 |         MASTER-OAFA | (10h 10m 56.31s , -82d 11m 49.2s) |   C |    60 | 19.5 |        
  111342 | 2026-05-13 23:51:55 |         MASTER-OAFA | (10h 11m 03.48s , -82d 11m 44.4s) |   C |    60 | 19.6 |        
  111416 | 2026-05-13 23:53:10 |         MASTER-OAFA | (10h 11m 03.76s , -82d 09m 59.6s) |   C |    60 | 19.6 |        
  111493 | 2026-05-13 23:54:26 |         MASTER-OAFA | (10h 11m 03.44s , -82d 11m 36.7s) |   C |    60 | 19.6 |        
  111569 | 2026-05-13 23:55:42 |         MASTER-OAFA | (10h 11m 08.67s , -82d 10m 08.0s) |   C |    60 | 19.3 |        
  111642 | 2026-05-13 23:56:55 |         MASTER-OAFA | (10h 11m 04.41s , -82d 10m 48.5s) |   C |    60 | 18.6 |        
  111721 | 2026-05-13 23:58:14 |         MASTER-OAFA | (10h 11m 06.38s , -82d 09m 49.6s) |   C |    60 | 18.2 |        
  111805 | 2026-05-13 23:59:38 |         MASTER-OAFA | (10h 08m 14.34s , -84d 04m 05.1s) |   C |    60 | 17.5 |        
  111880 | 2026-05-14 00:00:53 |         MASTER-OAFA | (10h 08m 08.20s , -84d 05m 00.1s) |   C |    60 | 17.9 |        
  111956 | 2026-05-14 00:02:09 |         MASTER-OAFA | (10h 08m 17.81s , -84d 04m 38.0s) |   C |    60 | 18.2 |        
  112035 | 2026-05-14 00:03:28 |         MASTER-OAFA | (10h 12m 11.06s , -80d 13m 12.6s) |   C |    60 | 18.4 |        
  112111 | 2026-05-14 00:04:44 |         MASTER-OAFA | (10h 12m 11.82s , -80d 14m 41.3s) |   C |    60 | 18.3 |        
  112186 | 2026-05-14 00:05:59 |         MASTER-OAFA | (10h 12m 17.07s , -80d 13m 35.4s) |   C |    60 | 18.6 |        
  112262 | 2026-05-14 00:07:15 |         MASTER-OAFA | (09h 58m 34.51s , -80d 14m 16.2s) |   C |    60 | 19.3 |        
  112341 | 2026-05-14 00:08:34 |         MASTER-OAFA | (09h 58m 35.92s , -80d 13m 16.8s) |   C |    60 | 19.3 |        
  112416 | 2026-05-14 00:09:49 |         MASTER-OAFA | (09h 58m 42.73s , -80d 14m 14.8s) |   C |    60 | 19.3 |        
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