GCN Circular 44050

Subject
Fermi GRB 260318A: Global MASTER-Net observations report
Event
GRB 260318A
Date
2026-03-18T23:00:55Z (22 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-Kislovodsk robotic telescope  [1]  located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB 260318A ( Fermi GBM team, GCN 44049Loading...
 
 ) errorbox  572 sec after notice time and 596 sec after trigger time at 2026-03-18 22:45:44 UT, with upper limit up to  18.1 mag. The observations began at zenith distance = 62 deg. The sun  altitude  is -43.5 deg. 

The galactic latitude b = 12 deg., longitude l = 92 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=3194853

We obtain a following upper limits.  

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

     657 | 2026-03-18 22:45:44 |   MASTER-Kislovodsk | (20h 14m 11.39s , +56d 41m 32.7s) |  P| |   120 | 17.6 |        
     797 | 2026-03-18 22:48:04 |   MASTER-Kislovodsk | (20h 14m 11.18s , +56d 41m 32.8s) |  P| |   120 | 17.4 |        
     938 | 2026-03-18 22:50:25 |   MASTER-Kislovodsk | (20h 14m 11.08s , +56d 41m 36.1s) |  P| |   120 | 18.1 |        
    1078 | 2026-03-18 22:52:45 |   MASTER-Kislovodsk | (20h 14m 11.06s , +56d 41m 40.9s) |  P| |   120 | 18.0 |        


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