Back
GCN Circular 36220

Subject
Fermi GRB 240421B: Global MASTER-Net observations report
Date
2024-04-22T02:15:40Z (12 days ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
Via
legacy email
V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik,  D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(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. Gress, N.M. Budnev, O.Ershova
(Irkutsk State University, API),

L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez
(INAOE, Guillermo Haro Astrophysics Observatory),

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

V. Yurkov, A. Gabovich
(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) started inspect of the Fermi GRB 240421B ( C. Fletcher (USRA) and C. Meegan (UAH) report on behalf of et al., GCN 36218Not found
 
 
) errorbox  19358 sec after notice time and 56607 sec after trigger time at 2024-04-22 01:26:08 UT, with upper limit up to  17.1 mag. Observations started at twilight.  The observations began at zenith distance = 67 deg. The sun  altitude  is -14.1 deg. 

The galactic latitude b = -22 deg., longitude l = 22 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2430649

We obtain a following upper limits.  

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

   56637 | 2024-04-22 01:26:08 |      MASTER-Tavrida | (19h 37m 21.45s , -18d 16m 09.9s) |   C |    60 | 16.4 |        
   56785 | 2024-04-22 01:28:36 |      MASTER-Tavrida | (19h 53m 26.05s , -18d 16m 57.8s) |   C |    60 | 14.1 |        
   56858 | 2024-04-22 01:29:50 |      MASTER-Tavrida | (19h 49m 21.85s , -22d 05m 18.0s) |   C |    60 | 14.2 |        
   57563 | 2024-04-22 01:41:35 |      MASTER-Tavrida | (19h 50m 44.40s , -20d 11m 20.7s) |   C |    60 | 15.8 |        
   57636 | 2024-04-22 01:42:47 |      MASTER-Tavrida | (19h 59m 17.11s , -20d 10m 02.0s) |   C |    60 | 16.6 |        
   57709 | 2024-04-22 01:44:00 |      MASTER-Tavrida | (19h 37m 21.08s , -18d 16m 19.0s) |   C |    60 | 17.1 |        
   57782 | 2024-04-22 01:45:13 |      MASTER-Tavrida | (19h 45m 45.17s , -18d 15m 26.6s) |   C |    60 | 17.0 |        
   57926 | 2024-04-22 01:47:38 |      MASTER-Tavrida | (19h 43m 02.18s , -20d 11m 33.0s) |   C |    60 | 16.8 |        
   57999 | 2024-04-22 01:48:50 |      MASTER-Tavrida | (19h 53m 25.96s , -18d 17m 25.9s) |   C |    60 | 16.7 |        
   58144 | 2024-04-22 01:51:16 |      MASTER-Tavrida | (19h 49m 20.84s , -22d 05m 40.1s) |   C |    60 | 14.5 |        
Filter C is a clear (unfiltred) band. 


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