TITLE:   GCN CIRCULAR
NUMBER:  31810
SUBJECT: Fermi  trigger No 670501065: Global MASTER-Net observations report 
DATE:    22/04/01 17:30:45 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-Tavrida robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB220401.43 (trigger No 670501065,00h 39m 48.00s , +52d 42m 36.0s, R=4.55) errorbox  25457 sec after notice time and 25468 sec after trigger time at 2022-04-01 17:22:08 UT, with upper limit up to  14.1 mag. Observations started at twilight.  The observations began at zenith distance = 67 deg. The sun  altitude  is -13.6 deg. 

The galactic latitude b = -10 deg., longitude l = 122 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1929363

We obtain a following upper limits.  

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

   25498 | 2022-04-01 17:22:08 |      MASTER-Tavrida | (00h 46m 37.78s , +54d 01m 12.7s) |   C |    60 | 14.1 |        
   25578 | 2022-04-01 17:23:28 |      MASTER-Tavrida | (01h 00m 18.46s , +54d 03m 20.4s) |   C |    60 | 13.6 |        
Filter C is a clear (unfiltred) band. 


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