TITLE:   GCN CIRCULAR
NUMBER:  29214
SUBJECT: Fermi  trigger No 631113166: Global MASTER-Net observations report 
DATE:    21/01/01 03:30:21 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 GRB201231.55 (trigger No 631113166,16h 05m 04.80s , -05d 28m 48.0s, R=2.53) errorbox  28347 sec after notice time and 47754 sec after trigger time at 2021-01-01 02:28:35 UT, with upper limit up to  17.8 mag. The observations began at zenith distance = 77 deg. The sun  altitude  is -29.4 deg. 

The galactic latitude b = 32 deg., longitude l =  6 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1516288

We obtain a following upper limits.  

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

   47784 | 2021-01-01 02:28:35 |      MASTER-Tavrida | (16h 10m 45.95s , -01d 47m 28.8s) |   C |    60 | 16.4 |        
   49040 | 2021-01-01 02:49:31 |      MASTER-Tavrida | (15h 56m 25.48s , -03d 46m 02.6s) |   C |    60 | 16.8 |        
   49358 | 2021-01-01 02:54:49 |      MASTER-Tavrida | (16h 10m 45.19s , -01d 45m 55.1s) |   C |    60 | 17.4 |        
   49793 | 2021-01-01 03:02:05 |      MASTER-Tavrida | (16h 15m 21.28s , -05d 46m 56.1s) |   C |    60 | 13.7 |        
   50032 | 2021-01-01 03:06:04 |      MASTER-Tavrida | (15h 56m 25.79s , -03d 45m 43.2s) |   C |    60 | 17.8 |        
   50350 | 2021-01-01 03:11:21 |      MASTER-Tavrida | (16h 10m 46.09s , -01d 45m 40.0s) |   C |    60 | 17.6 |        
   50565 | 2021-01-01 03:14:56 |      MASTER-Tavrida | (16h 08m 43.66s , -09d 44m 24.3s) |   C |    60 | 17.1 |        
   50644 | 2021-01-01 03:16:16 |      MASTER-Tavrida | (15h 59m 23.53s , -05d 45m 08.7s) |   C |    60 | 17.6 |        
   50724 | 2021-01-01 03:17:35 |      MASTER-Tavrida | (16h 03m 22.97s , -07d 46m 14.4s) |   C |    60 | 17.2 |        
   50803 | 2021-01-01 03:18:54 |      MASTER-Tavrida | (16h 12m 30.89s , -03d 46m 34.5s) |   C |    60 | 17.5 |        
   50883 | 2021-01-01 03:20:14 |      MASTER-Tavrida | (16h 15m 25.53s , -05d 44m 53.1s) |   C |    60 | 17.4 |        
Filter C is a clear (unfiltred) band. 


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