[vsnet-grb-info 28459] Swift GRB 210730A: Global MASTER-Net observations report

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  30562
SUBJECT: Swift GRB 210730A: Global MASTER-Net observations report 
DATE:    21/07/31 05:00:27 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-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) was pointed to the Swift GRB 210730A ( E. Sonbas et al., GCN 30548) errorbox  47961 sec after notice time and 47903 sec after trigger time at 2021-07-30 18:17:14 UT, with upper limit up to  19.2 mag. Observations started at twilight.  The observations began at zenith distance = 54 deg. The sun  altitude  is -11.0 deg. 

MASTER-IAC robotic telescope  located in Spain (IAC Teide Observatory) was pointed to the Swift GRB 210730A errorbox  64883 sec after notice time and 64826 sec after trigger time at 2021-07-30 22:59:17 UT, with upper limit up to  17.7 mag. The observations began at zenith distance = 76 deg. The sun  altitude  is -34.0 deg. 

MASTER-Kislovodsk robotic telescope  located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) was pointed to the Swift GRB 210730A errorbox  71489 sec after notice time and 71432 sec after trigger time at 2021-07-31 00:49:22 UT, with upper limit up to  16.5 mag. Observations started at twilight.  The observations began at zenith distance = 65 deg. The sun  altitude  is -11.7 deg. 

The galactic latitude b = 41 deg., longitude l = 141 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1675497

We obtain a following upper limits.  

Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________

   47934 |      MASTER-Tavrida |   C |    60 | 17.0 |        
   48488 |      MASTER-Tavrida |   C |    60 | 17.9 |        
   48962 |      MASTER-Tavrida |   C |    60 | 18.4 |        
   49437 |      MASTER-Tavrida |   C |    60 | 18.8 |        
   49912 |      MASTER-Tavrida |   C |    60 | 18.7 |        
   50386 |      MASTER-Tavrida |   C |    60 | 19.1 |        
   50684 |      MASTER-Tavrida |   C |   180 | 18.9 |        
   51671 |      MASTER-Tavrida |   C |   180 | 19.2 |        
   64916 |          MASTER-IAC |   C |   180 | 17.5 |        
   64916 |          MASTER-IAC |   C |   180 | 17.3 |        
   65096 |          MASTER-IAC |   C |   540 | 17.7 |  Coadd 
   65131 |          MASTER-IAC |   C |   180 | 17.2 |        
   65131 |          MASTER-IAC |   C |   180 | 16.8 |        
   65311 |          MASTER-IAC |   C |   540 | 17.5 |  Coadd 
   65341 |          MASTER-IAC |   C |   180 | 17.2 |        
   65341 |          MASTER-IAC |   C |   180 | 17.0 |        
   65551 |          MASTER-IAC |   C |   180 | 17.1 |        
   65551 |          MASTER-IAC |   C |   180 | 16.8 |        
   65760 |          MASTER-IAC |   C |   180 | 17.0 |        
   65760 |          MASTER-IAC |   C |   180 | 17.0 |        
   65970 |          MASTER-IAC |   C |   180 | 17.2 |        
   65970 |          MASTER-IAC |   C |   180 | 16.7 |        
   66179 |          MASTER-IAC |   C |   180 | 17.0 |        
   66179 |          MASTER-IAC |   C |   180 | 16.9 |        
   66394 |          MASTER-IAC |   C |   180 | 17.1 |        
   66394 |          MASTER-IAC |   C |   180 | 16.8 |        
   66604 |          MASTER-IAC |   C |   180 | 17.0 |        
   66604 |          MASTER-IAC |   C |   180 | 16.8 |        
   66815 |          MASTER-IAC |   C |   180 | 17.1 |        
   66815 |          MASTER-IAC |   C |   180 | 16.6 |        
   67023 |          MASTER-IAC |   C |   180 | 17.0 |        
   67023 |          MASTER-IAC |   C |   180 | 16.7 |        
   67238 |          MASTER-IAC |   C |   180 | 17.0 |        
   67238 |          MASTER-IAC |   C |   180 | 16.7 |        
   67565 |          MASTER-IAC |   C |    60 | 16.7 |        
   67834 |          MASTER-IAC |   C |    60 | 16.7 |        
   67834 |          MASTER-IAC |   C |    60 | 16.2 |        
   67923 |          MASTER-IAC |   C |    60 | 16.0 |        
   68440 |          MASTER-IAC |   C |   180 | 16.9 |        
   68440 |          MASTER-IAC |   C |   180 | 16.6 |        
   68770 |          MASTER-IAC |   C |    60 | 16.4 |        
   69041 |          MASTER-IAC |   C |    60 | 16.5 |        
   69041 |          MASTER-IAC |   C |    60 | 16.0 |        
   69130 |          MASTER-IAC |   C |    60 | 15.7 |        
   69636 |          MASTER-IAC |   C |   180 | 16.6 |        
   69636 |          MASTER-IAC |   C |   180 | 16.3 |        
   69964 |          MASTER-IAC |   C |    60 | 16.2 |        
   70235 |          MASTER-IAC |   C |    60 | 16.4 |        
   70235 |          MASTER-IAC |   C |    60 | 15.8 |        
   70323 |          MASTER-IAC |   C |    60 | 15.5 |        
   70835 |          MASTER-IAC |   C |   180 | 16.4 |        
   70835 |          MASTER-IAC |   C |   180 | 15.9 |        
   71522 |   MASTER-Kislovodsk |   C |   180 | 16.5 |        
   71722 |   MASTER-Kislovodsk |   C |   180 | 16.1 |        
   72000 |          MASTER-IAC |   C |   180 | 16.1 |        
   72000 |          MASTER-IAC |   C |   180 | 16.0 |        
   73190 |          MASTER-IAC |   C |   180 | 15.8 |        
   73190 |          MASTER-IAC |   C |   180 | 15.9 |        
Filter C is a clear (unfiltred) band. 


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