[vsnet-grb-info 27814] Fermi GRB 210430B: Global MASTER-Net observations report

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  29917
SUBJECT: Fermi GRB 210430B: Global MASTER-Net observations report 
DATE:    21/04/30 23:45:14 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov at 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-Kislovodsk robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB 210430B ( Fermi GBM team, GCN 29916) errorbox  6673 sec after notice time and 6710 sec after trigger time at 2021-04-30 23:34:08 UT, with upper limit up to  17.1 mag. The observations began at zenith distance = 79 deg. The sun  altitude  is -23.0 deg. 

The galactic latitude b = -47 deg., longitude l = 86 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1604728

We obtain a following upper limits.  

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

    6741 | 2021-04-30 23:34:08 |   MASTER-Kislovodsk | (22h 47m 52.89s , +14d 03m 13.2s) |   C |    60 | 16.9 |        
    6741 | 2021-04-30 23:34:08 |   MASTER-Kislovodsk | (22h 51m 45.19s , +13d 39m 00.0s) |   C |    60 | 17.1 |        
    6901 | 2021-04-30 23:36:49 |   MASTER-Kislovodsk | (22h 43m 52.25s , +10d 04m 18.5s) |   C |    60 | 16.9 |        
    6901 | 2021-04-30 23:36:49 |   MASTER-Kislovodsk | (22h 47m 40.74s , +09d 40m 01.6s) |   C |    60 | 16.9 |        
Filter C is a clear (unfiltred) band. 


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