TITLE:   GCN CIRCULAR
NUMBER:  31623
SUBJECT: IceCube Alert 220221.03: Global MASTER-Net observations report 
DATE:    22/02/21 17:39:16 GMT
FROM:    Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>

V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, 
D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, T.Pogrosheva, E.Minkina,
A.Chasovnikov, V.Topolev, V.Grinshpun, 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
(Irkutsk State University, API),

B.L.Carrasco, J.R.Valdes,V.Chavushyan, C.J.Martinez, V.M.Patino Alvarez,
M.L.H.Rodriguez (INAOE, OAGH)

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

A. Gabovich, V.Yurkov 
(Blagoveschensk Educational State University)


MASTER-Amur robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the IceCube Alert 220221.03 (trigger No 65788242,19h 19m 24.72s , +36d 05m 52.8s, R=7.37) errorbox  58455 sec after notice time and 58500 sec after trigger time at 2022-02-21 16:57:19 UT, with upper limit up to  16.4 mag. The observations began at zenith distance = 70 deg. The sun  altitude  is -47.7 deg. 

The galactic latitude b = 10 deg., longitude l = 69 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1889953

We obtain a following upper limits.  

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

   58531 | 2022-02-21 16:57:19 |         MASTER-Amur | (18h 39m 59.74s , +39d 33m 05.0s) |   C |    60 | 16.1 |        
   58610 | 2022-02-21 16:58:39 |         MASTER-Amur | (18h 54m 15.84s , +43d 19m 18.5s) |   C |    60 | 16.4 |        
   58690 | 2022-02-21 16:59:58 |         MASTER-Amur | (19h 05m 18.73s , +43d 19m 32.2s) |   C |    60 | 16.4 |        
Filter C is a clear (unfiltred) band. 


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