TITLE:   GCN CIRCULAR
NUMBER:  32083
SUBJECT: Fermi  trigger No 674868783: Global MASTER-Net observations report 
DATE:    22/05/22 09:15:24 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

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-OAGH robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Mexico (OAGH National Institute for Astrophysics, Optics and Electronics) started inspect of the Fermi GRB220521.98 (trigger No 674868783,22h 03m 55.92s , -08d 04m 01.2s, R=32.7) errorbox  34381 sec after notice time and 34419 sec after trigger time at 2022-05-22 09:06:37 UT, with upper limit up to  17.7 mag. The observations began at zenith distance = 68 deg. The sun  altitude  is -32.1 deg. 

The galactic latitude b = -46 deg., longitude l = 51 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1980507

We obtain a following upper limits.  

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

   34509 | 2022-05-22 09:06:37 |         MASTER-OAGH | (22h 17m 01.29s , +05d 23m 56.7s) |   C |   180 | 16.7 |        
   34509 | 2022-05-22 09:06:37 |         MASTER-OAGH | (22h 17m 22.89s , +04d 59m 38.4s) |   C |   180 | 17.7 |        
Filter C is a clear (unfiltred) band. 


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