[vsnet-grb-info 25514] IceCube Alert 200421.02: Global MASTER-Net observations report

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27614
SUBJECT: IceCube Alert 200421.02: Global MASTER-Net observations report 
DATE:    20/04/21 13:39:10 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),

H.Levato 
(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),

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-Tunka robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the IceCube Alert 200421.02 (trigger No 60770138,05h 57m 01.20s , +07d 54m 25.2s, R=0.61) errorbox  45894 sec after notice time and 45943 sec after trigger time at 2020-04-21 13:21:07 UT, with upper limit up to  15.6 mag. Observations started at twilight.  The observations began at zenith distance = 68 deg. The sun  altitude  is -10.4 deg. 

The galactic latitude b = -8 deg., longitude l = 200 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1341229

We obtain a following upper limits.  

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

   45973 | 2020-04-21 13:21:07 |        MASTER-Tunka | (05h 51m 49.84s , +08d 17m 27.8s) |   C |    60 | 15.3 |        
   46053 | 2020-04-21 13:22:27 |        MASTER-Tunka | (05h 59m 58.32s , +08d 19m 28.6s) |   C |    60 | 15.6 |        
Filter C is a clear (unfiltred) band. 


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