GCN Circular 31712

V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, 
G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov,  D.Cheryasov, Ya.Kechin
(Lomonosov Moscow State University, SAI, Physics Department),

R. Podesta, C.Lopez, F. Podesta, C.Francile 
(Observatorio Astronomico Felix Aguilar OAFA),

R. Rebolo, M. Serra 
(The Instituto de Astrofisica de Canarias),

D. Buckley 
(South African Astronomical Observatory),

O.A. Gres, N.M. Budnev
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez 
(INAOE, Guillermo Haro Astrophysics Observatory),

A. Tlatov, D. Dormidontov 
(Kislovodsk Solar Station of the Pulkovo Observatory),

A. Gabovich, V.Yurkov 
(Blagoveschensk Educational State University)


MASTER-OAFA robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB220308.23 (trigger No 668410535,19h 27m 19.20s , +26d 26m 24.0s, R=5.29) errorbox 12912 sec after trigger time at 2022-03-08 09:10:42 UT, with upper limit up to  18.5 mag. The observations began at zenith distance = 73 deg. The sun  altitude  is -17.4 deg. 

MASTER-OAGH robotic telescope  located in Mexico (OAGH National Institute for Astrophysics, Optics and Electronics) started inspect of the Fermi GRB220308.23 errorbox 21903 sec after trigger time at 2022-03-08 11:40:33 UT, with upper limit up to  19.4 mag. The observations began at zenith distance = 54 deg. The sun  altitude  is -25.8 deg. 

MASTER-Amur robotic telescope  located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB220308.23 errorbox  32 sec after notice time and 42434 sec after trigger time at 2022-03-08 17:22:44 UT, with upper limit up to  15.7 mag. The observations began at zenith distance = 75 deg. The sun  altitude  is -40.1 deg. 

The galactic latitude b =  4 deg., longitude l = 61 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1904572

We obtain a following upper limits.  

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

   13003 | 2022-03-08 09:10:42 |         MASTER-OAFA | (19h 21m 05.82s , +19d 17m 45.2s) |   C |   180 | 18.5 |        
   21993 | 2022-03-08 11:40:33 |         MASTER-OAGH | (19h 20m 05.47s , +20d 01m 41.8s) |   C |   180 | 19.4 |        
   21993 | 2022-03-08 11:40:33 |         MASTER-OAGH | (19h 20m 30.72s , +19d 36m 32.7s) |   C |   180 | 19.2 |        
   22685 | 2022-03-08 11:52:04 |         MASTER-OAGH | (19h 20m 04.23s , +20d 00m 12.0s) |   C |   180 | 19.4 |        
   22685 | 2022-03-08 11:52:04 |         MASTER-OAGH | (19h 20m 28.73s , +19d 35m 00.5s) |   C |   180 | 19.1 |        
   26462 | 2022-03-08 12:55:02 |         MASTER-OAGH | (19h 20m 11.61s , +20d 01m 23.5s) |   C |   180 | 18.0 |        
   26462 | 2022-03-08 12:55:02 |         MASTER-OAGH | (19h 20m 31.93s , +19d 36m 20.8s) |   C |   180 | 17.8 |        
   42524 | 2022-03-08 17:22:44 |         MASTER-Amur | (19h 30m 03.74s , +26d 41m 14.3s) |   C |   180 | 15.4 |        
   42724 | 2022-03-08 17:26:03 |         MASTER-Amur | (19h 30m 09.90s , +26d 41m 10.2s) |   C |   180 | 15.6 |        
   42923 | 2022-03-08 17:29:23 |         MASTER-Amur | (19h 30m 07.95s , +26d 43m 03.7s) |   C |   180 | 15.6 |        
   43123 | 2022-03-08 17:32:43 |         MASTER-Amur | (19h 30m 08.07s , +26d 41m 04.5s) |   C |   180 | 15.7 |        
Filter C is a clear (unfiltred) band. 


The observation and reduction will continue. 
The message may be cited.