TITLE:   GCN CIRCULAR
NUMBER:  31124
SUBJECT: IceCube Alert 211125.27: Global MASTER-Net observations report 
DATE:    21/11/25 12:39:14 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),

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

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


MASTER-OAFA robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L)  located in Argentina (OAFA observatory of San Juan National University) started inspect of the IceCube Alert 211125.27 (trigger No 74588253,02h 54m 39.84s , +21d 32m 31.2s, R=1.08) errorbox  201 sec after notice time and 242 sec after trigger time at 2021-11-25 06:26:23 UT, with upper limit up to  18.0 mag. The observations began at zenith distance = 69 deg. The sun  altitude  is -30.2 deg. 

The galactic latitude b = -32 deg., longitude l = 158 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=1795993

We obtain a following upper limits.  

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

     277 | 2021-11-25 06:26:23 |         MASTER-OAFA | (02h 54m 54.02s , +20d 45m 09.9s) |   C |    70 | 17.7 |        
     377 | 2021-11-25 06:27:53 |         MASTER-OAFA | (02h 54m 47.02s , +20d 44m 15.3s) |   C |    90 | 17.8 |        
     496 | 2021-11-25 06:29:42 |         MASTER-OAFA | (02h 54m 52.70s , +20d 44m 42.7s) |   C |   110 | 18.0 |        
     636 | 2021-11-25 06:31:52 |         MASTER-OAFA | (02h 54m 50.15s , +20d 46m 08.7s) |   C |   130 | 17.9 |        
     800 | 2021-11-25 06:34:21 |         MASTER-OAFA | (02h 54m 49.88s , +20d 44m 32.6s) |   C |   160 | 17.9 |        
     990 | 2021-11-25 06:37:21 |         MASTER-OAFA | (02h 54m 53.14s , +20d 46m 08.2s) |   C |   180 | 18.0 |        
    1189 | 2021-11-25 06:40:40 |         MASTER-OAFA | (02h 54m 46.30s , +20d 45m 18.3s) |   C |   180 | 17.9 |        
    1389 | 2021-11-25 06:44:00 |         MASTER-OAFA | (02h 54m 45.76s , +20d 46m 15.8s) |   C |   180 | 17.8 |        
    1588 | 2021-11-25 06:47:19 |         MASTER-OAFA | (02h 54m 52.84s , +20d 45m 12.9s) |   C |   180 | 17.7 |        
    1788 | 2021-11-25 06:50:39 |         MASTER-OAFA | (02h 54m 46.90s , +20d 44m 09.1s) |   C |   180 | 17.6 |        
Filter C is a clear (unfiltred) band. 


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