TITLE:   GCN CIRCULAR
NUMBER:  34114
SUBJECT: Fermi GRB 230628D: Global MASTER-Net observations report
DATE:    23/06/29 02:00:34 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, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov,  D.Cheryasov, Ya.Kechin
(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),

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),

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 Fermi GRB 230628D ( Fermi GBM team, GCN 34108) errorbox  15347 sec after notice time and 15383 sec after trigger time at 2023-06-29 00:38:54 UT, with upper limit up to  19.0 mag. The observations began at zenith distance = 60 deg. The sun  altitude  is -36.9 deg. 

The galactic latitude b = 68 deg., longitude l = 253 deg.


Real time updated cover map and OT discovered available here: 
https://master.sai.msu.ru/site/master2/observ.php?id=2230025

We obtain a following upper limits.  

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

   15473 | 2023-06-29 00:38:54 |         MASTER-OAFA | (11h 38m 17.90s , +12d 57m 37.4s) |   C |   180 | 18.3 |        
   15653 | 2023-06-29 00:38:54 |         MASTER-OAFA | (11h 38m 17.90s , +12d 57m 37.4s) |   C |   540 | 19.0 |  Coadd 
   15685 | 2023-06-29 00:42:26 |         MASTER-OAFA | (11h 38m 23.91s , +12d 56m 35.9s) |   C |   180 | 18.2 |        
   16524 | 2023-06-29 00:56:25 |         MASTER-OAFA | (11h 38m 20.58s , +12d 55m 38.5s) |   C |   180 | 18.1 |        
   18504 | 2023-06-29 01:29:25 |         MASTER-OAFA | (11h 42m 15.16s , +13d 09m 29.7s) |   C |   180 | 17.8 |        
   18684 | 2023-06-29 01:29:25 |         MASTER-OAFA | (11h 42m 15.16s , +13d 09m 29.7s) |   C |   540 | 18.5 |  Coadd 
   18716 | 2023-06-29 01:32:57 |         MASTER-OAFA | (11h 42m 15.00s , +13d 08m 03.9s) |   C |   180 | 17.8 |        
   18927 | 2023-06-29 01:36:28 |         MASTER-OAFA | (11h 42m 16.98s , +13d 09m 21.5s) |   C |   180 | 17.9 |        
   19137 | 2023-06-29 01:39:58 |         MASTER-OAFA | (11h 42m 12.15s , +13d 08m 40.0s) |   C |   180 | 17.6 |        
   19581 | 2023-06-29 01:47:22 |         MASTER-OAFA | (11h 38m 17.87s , +11d 38m 32.8s) |   C |   180 | 17.6 |        
   19792 | 2023-06-29 01:50:54 |         MASTER-OAFA | (11h 38m 12.10s , +11d 37m 29.1s) |   C |   180 | 17.9 |        
Filter C is a clear (unfiltred) band. 


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