TITLE:   GCN CIRCULAR
NUMBER:  30818
SUBJECT: Fermi  trigger No 653066776: Global MASTER-Net observations report 
DATE:    21/09/11 22:30:14 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, 
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,
D.Kuvshinov,  D. Cheryasov
(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, O.Ershova 
(Irkutsk State University, API),

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

V. Yurkov, A. Gabovich, Yu. Sergienko 
(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 GRB210911.64 (trigger No 653066776,19h 54m 52.80s , +10d 04m 48.0s, R=4.24) errorbox  22093 sec after notice time and 22135 sec after trigger time at 2021-09-11 21:35:07 UT, with upper limit up to  18.3 mag. The observations began at zenith distance = 49 deg. The sun  altitude  is -41.7 deg. 

The galactic latitude b = -10 deg., longitude l = 50 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1717607

We obtain a following upper limits.  

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

   22166 | 2021-09-11 21:35:07 |      MASTER-Tavrida | (20h 01m 18.32s , +16d 06m 41.1s) |   C |    60 | 18.3 |        
   22796 | 2021-09-11 21:45:37 |      MASTER-Tavrida | (19h 48m 57.15s , +12d 19m 07.8s) |   C |    60 | 17.7 |        
   23724 | 2021-09-11 22:01:05 |      MASTER-Tavrida | (19h 40m 52.24s , +12d 17m 26.1s) |   C |    60 | 17.2 |        
   23803 | 2021-09-11 22:02:24 |      MASTER-Tavrida | (19h 48m 56.93s , +12d 16m 26.0s) |   C |    60 | 17.5 |        
   23882 | 2021-09-11 22:03:43 |      MASTER-Tavrida | (20h 05m 58.01s , +14d 12m 15.3s) |   C |    60 | 18.2 |        
Filter C is a clear (unfiltred) band. 


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