GCN Circular 45771
Subject
EP260924a: Global MASTER-Net observations report
Event
Date
2026-09-27T22:10:00Z (17 hours ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
Via
email
M. Segura, F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA)
O.Gress, N.Budnev(ISU)
V.Lipunov, E.Gorbovskoy, A.Kuznetsov, K.Zhirkov, I.Panchenko, N.Tiurina, P.Balanutsa, V.Topolev, D.Vlasenko,
G.Antipov, A.Sankovich, Yu.Tselik, Ya..Kechin, V.Senik, A.Chasovnikov, K.Labsina (Lomonosov MSU)
D.Buckley (SAAO),
A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity)
A.Sosnovskij (Lomonosov MSU)
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory)
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory)
R.Rebolo (The Instituto de Astrofisica de Canarias)
MASTER-OAFA robotic telescope [1] located in Argentina (OAFA observatory of San Juan National University) was pointed to the EP260924a ( EP Team at NAOC/CAS <ep_ta@bao.ac.cn> et al., GCN 45737) errorbox 37856 sec after trigger time at 2026-09-26 01:54:57 UT, with upper limit up to 17.5 mag. The observations began at zenith distance = 80 deg. The sun altitude is -41.2 deg.
MASTER-Tunka robotic telescope located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the EP260924a errorbox 29448 sec after notice time and 74429 sec after trigger time at 2026-09-26 12:04:30 UT, with upper limit up to 18.6 mag. Observations started at twilight. The observations began at zenith distance = 32 deg. The sun altitude is -11.2 deg.
The galactic latitude b = -10 deg., longitude l = 101 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=3511773
We obtain a following upper limits.
Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
37886 | 2026-09-26 01:54:57 | MASTER-OAFA | (22h 36m 03.94s , +46d 52m 07.4s) | C | 60 | 16.2 |
37946 | 2026-09-26 01:54:57 | MASTER-OAFA | (22h 36m 04.05s , +46d 51m 59.7s) | C | 180 | 16.9 | Coadd
39889 | 2026-09-26 02:28:19 | MASTER-OAFA | (22h 34m 33.57s , +46d 46m 42.3s) | C | 60 | 16.9 |
39971 | 2026-09-26 02:29:41 | MASTER-OAFA | (22h 34m 40.43s , +46d 46m 51.9s) | C | 60 | 16.9 |
40049 | 2026-09-26 02:31:00 | MASTER-OAFA | (22h 34m 36.21s , +46d 48m 25.6s) | C | 60 | 16.9 |
40109 | 2026-09-26 02:31:00 | MASTER-OAFA | (22h 34m 36.24s , +46d 48m 25.4s) | C | 180 | 17.5 | Coadd
40123 | 2026-09-26 02:32:14 | MASTER-OAFA | (22h 34m 35.98s , +46d 47m 01.5s) | C | 60 | 16.9 |
40198 | 2026-09-26 02:33:28 | MASTER-OAFA | (22h 34m 38.26s , +46d 48m 50.1s) | C | 60 | 16.9 |
40271 | 2026-09-26 02:34:42 | MASTER-OAFA | (22h 34m 31.91s , +46d 47m 53.6s) | C | 60 | 16.8 |
40331 | 2026-09-26 02:34:42 | MASTER-OAFA | (22h 34m 31.91s , +46d 47m 53.2s) | C | 180 | 17.3 | Coadd
40349 | 2026-09-26 02:35:59 | MASTER-OAFA | (22h 34m 33.43s , +46d 48m 55.3s) | C | 60 | 16.7 |
40426 | 2026-09-26 02:37:16 | MASTER-OAFA | (22h 34m 38.47s , +46d 47m 57.2s) | C | 60 | 16.8 |
43874 | 2026-09-26 03:34:44 | MASTER-OAFA | (22h 34m 24.33s , +46d 48m 13.7s) | C | 60 | 16.2 |
43953 | 2026-09-26 03:36:04 | MASTER-OAFA | (22h 34m 20.79s , +46d 49m 45.2s) | C | 60 | 16.1 |
44032 | 2026-09-26 03:37:22 | MASTER-OAFA | (22h 34m 20.41s , +46d 48m 21.2s) | C | 60 | 16.1 |
44109 | 2026-09-26 03:38:39 | MASTER-OAFA | (22h 34m 24.06s , +46d 49m 39.9s) | C | 60 | 16.0 |
74460 | 2026-09-26 12:04:30 | MASTER-Tunka | (22h 34m 43.51s , +46d 43m 34.6s) | C | 60 | 18.2 | Coadd
74460 | 2026-09-26 12:04:31 | MASTER-Tunka | (22h 34m 11.94s , +46d 50m 36.9s) | C | 60 | 18.1 |
74550 | 2026-09-26 12:06:01 | MASTER-Tunka | (22h 34m 38.21s , +46d 42m 31.6s) | C | 60 | 18.3 | Coadd
74550 | 2026-09-26 12:06:01 | MASTER-Tunka | (22h 34m 06.38s , +46d 49m 34.0s) | C | 60 | 18.3 |
74641 | 2026-09-26 12:07:31 | MASTER-Tunka | (22h 34m 43.74s , +46d 42m 30.1s) | C | 60 | 18.3 | Coadd
74641 | 2026-09-26 12:07:31 | MASTER-Tunka | (22h 34m 11.67s , +46d 49m 32.6s) | C | 60 | 18.2 |
74731 | 2026-09-26 12:09:02 | MASTER-Tunka | (22h 34m 41.00s , +46d 44m 23.0s) | C | 60 | 18.3 | Coadd
74731 | 2026-09-26 12:09:02 | MASTER-Tunka | (22h 34m 08.72s , +46d 51m 25.3s) | C | 60 | 18.2 |
74812 | 2026-09-26 12:10:23 | MASTER-Tunka | (22h 34m 08.71s , +46d 49m 44.2s) | C | 60 | 18.3 |
74812 | 2026-09-26 12:10:23 | MASTER-Tunka | (22h 34m 41.13s , +46d 42m 42.1s) | C | 60 | 18.3 | Coadd
74895 | 2026-09-26 12:11:46 | MASTER-Tunka | (22h 34m 43.75s , +46d 44m 15.5s) | C | 60 | 18.3 | Coadd
74896 | 2026-09-26 12:11:46 | MASTER-Tunka | (22h 34m 11.15s , +46d 51m 17.4s) | C | 60 | 18.3 |
74981 | 2026-09-26 12:13:11 | MASTER-Tunka | (22h 34m 38.50s , +46d 43m 16.0s) | C | 60 | 18.5 | Coadd
74981 | 2026-09-26 12:13:11 | MASTER-Tunka | (22h 34m 05.70s , +46d 50m 17.8s) | C | 60 | 18.4 |
75056 | 2026-09-26 12:14:27 | MASTER-Tunka | (22h 34m 39.32s , +46d 44m 13.1s) | C | 60 | 18.4 | Coadd
75056 | 2026-09-26 12:14:27 | MASTER-Tunka | (22h 34m 06.38s , +46d 51m 15.1s) | C | 60 | 18.4 |
75137 | 2026-09-26 12:15:48 | MASTER-Tunka | (22h 34m 11.71s , +46d 50m 12.3s) | C | 60 | 18.4 |
75137 | 2026-09-26 12:15:48 | MASTER-Tunka | (22h 34m 44.80s , +46d 43m 10.3s) | C | 60 | 18.5 | Coadd
75217 | 2026-09-26 12:17:08 | MASTER-Tunka | (22h 34m 38.43s , +46d 42m 07.2s) | C | 60 | 18.5 | Coadd
75217 | 2026-09-26 12:17:08 | MASTER-Tunka | (22h 34m 05.17s , +46d 49m 09.2s) | C | 60 | 18.4 |
75299 | 2026-09-26 12:18:29 | MASTER-Tunka | (22h 34m 43.93s , +46d 42m 23.8s) | C | 60 | 18.5 | Coadd
75299 | 2026-09-26 12:18:29 | MASTER-Tunka | (22h 34m 10.46s , +46d 49m 25.9s) | C | 60 | 18.4 |
75379 | 2026-09-26 12:19:50 | MASTER-Tunka | (22h 34m 08.19s , +46d 51m 00.8s) | C | 60 | 18.5 |
75379 | 2026-09-26 12:19:50 | MASTER-Tunka | (22h 34m 41.92s , +46d 43m 58.7s) | C | 60 | 18.5 | Coadd
76215 | 2026-09-26 12:33:46 | MASTER-Tunka | (22h 34m 40.11s , +46d 42m 55.1s) | C | 60 | 18.5 | Coadd
76216 | 2026-09-26 12:33:46 | MASTER-Tunka | (22h 34m 01.96s , +46d 51m 03.4s) | C | 60 | 18.5 |
76292 | 2026-09-26 12:35:02 | MASTER-Tunka | (22h 34m 01.96s , +46d 49m 12.7s) | C | 60 | 18.4 |
76292 | 2026-09-26 12:35:02 | MASTER-Tunka | (22h 34m 40.13s , +46d 41m 04.4s) | C | 60 | 18.5 | Coadd
76371 | 2026-09-26 12:36:22 | MASTER-Tunka | (22h 34m 05.12s , +46d 50m 57.7s) | C | 60 | 18.5 |
76371 | 2026-09-26 12:36:22 | MASTER-Tunka | (22h 34m 43.34s , +46d 42m 49.5s) | C | 60 | 18.5 | Coadd
76449 | 2026-09-26 12:37:39 | MASTER-Tunka | (22h 34m 38.05s , +46d 41m 54.4s) | C | 60 | 18.6 | Coadd
76449 | 2026-09-26 12:37:39 | MASTER-Tunka | (22h 33m 59.71s , +46d 50m 02.6s) | C | 60 | 18.5 |
76528 | 2026-09-26 12:38:58 | MASTER-Tunka | (22h 34m 37.78s , +46d 42m 51.6s) | C | 60 | 18.5 | Coadd
76528 | 2026-09-26 12:38:58 | MASTER-Tunka | (22h 33m 59.26s , +46d 50m 59.7s) | C | 60 | 18.4 |
76605 | 2026-09-26 12:40:16 | MASTER-Tunka | (22h 34m 04.26s , +46d 49m 56.8s) | C | 60 | 18.4 |
76606 | 2026-09-26 12:40:16 | MASTER-Tunka | (22h 34m 42.87s , +46d 41m 48.8s) | C | 60 | 18.5 | Coadd
76683 | 2026-09-26 12:41:34 | MASTER-Tunka | (22h 33m 59.21s , +46d 48m 53.9s) | C | 60 | 18.4 |
76684 | 2026-09-26 12:41:34 | MASTER-Tunka | (22h 34m 37.95s , +46d 40m 45.8s) | C | 60 | 18.5 | Coadd
76760 | 2026-09-26 12:42:51 | MASTER-Tunka | (22h 34m 42.68s , +46d 41m 00.3s) | C | 60 | 18.5 | Coadd
76761 | 2026-09-26 12:42:51 | MASTER-Tunka | (22h 34m 03.84s , +46d 49m 08.2s) | C | 60 | 18.5 |
76838 | 2026-09-26 12:44:08 | MASTER-Tunka | (22h 34m 01.60s , +46d 50m 45.7s) | C | 60 | 18.4 |
76838 | 2026-09-26 12:44:08 | MASTER-Tunka | (22h 34m 40.57s , +46d 42m 37.6s) | C | 60 | 18.5 | Coadd
76915 | 2026-09-26 12:45:26 | MASTER-Tunka | (22h 34m 40.66s , +46d 41m 04.7s) | C | 60 | 18.5 | Coadd
76915 | 2026-09-26 12:45:26 | MASTER-Tunka | (22h 34m 01.59s , +46d 49m 12.6s) | C | 60 | 18.5 |
76992 | 2026-09-26 12:46:43 | MASTER-Tunka | (22h 34m 44.68s , +46d 42m 23.4s) | C | 60 | 18.5 | Coadd
76992 | 2026-09-26 12:46:43 | MASTER-Tunka | (22h 34m 05.45s , +46d 50m 31.2s) | C | 60 | 18.4 |
77070 | 2026-09-26 12:48:00 | MASTER-Tunka | (22h 34m 38.61s , +46d 41m 32.6s) | C | 60 | 18.5 | Coadd
77070 | 2026-09-26 12:48:00 | MASTER-Tunka | (22h 33m 59.30s , +46d 49m 40.4s) | C | 60 | 18.4 |
77529 | 2026-09-26 12:55:40 | MASTER-Tunka | (22h 34m 43.27s , +46d 41m 52.8s) | C | 60 | 18.6 | Coadd
77529 | 2026-09-26 12:55:40 | MASTER-Tunka | (22h 34m 04.10s , +46d 51m 31.7s) | C | 60 | 18.4 |
77606 | 2026-09-26 12:56:56 | MASTER-Tunka | (22h 34m 37.60s , +46d 41m 14.6s) | C | 60 | 18.6 | Coadd
77606 | 2026-09-26 12:56:56 | MASTER-Tunka | (22h 33m 58.23s , +46d 50m 52.9s) | C | 60 | 18.5 |
77684 | 2026-09-26 12:58:15 | MASTER-Tunka | (22h 33m 58.55s , +46d 51m 49.9s) | C | 60 | 18.5 |
77684 | 2026-09-26 12:58:15 | MASTER-Tunka | (22h 34m 38.01s , +46d 42m 11.8s) | C | 60 | 18.6 | Coadd
77762 | 2026-09-26 12:59:33 | MASTER-Tunka | (22h 34m 43.48s , +46d 41m 08.7s) | C | 60 | 18.6 | Coadd
77762 | 2026-09-26 12:59:33 | MASTER-Tunka | (22h 34m 03.96s , +46d 50m 46.9s) | C | 60 | 18.5 |
77839 | 2026-09-26 13:00:50 | MASTER-Tunka | (22h 34m 37.07s , +46d 40m 05.7s) | C | 60 | 18.6 | Coadd
77840 | 2026-09-26 13:00:50 | MASTER-Tunka | (22h 33m 57.44s , +46d 49m 43.8s) | C | 60 | 18.5 |
77924 | 2026-09-26 13:02:14 | MASTER-Tunka | (22h 34m 43.60s , +46d 40m 08.2s) | C | 60 | 18.6 | Coadd
77924 | 2026-09-26 13:02:14 | MASTER-Tunka | (22h 34m 03.85s , +46d 49m 46.3s) | C | 60 | 18.5 |
Filter C is a clear (unfiltred) band.
The observation and reduction will continue.
The message may be cited.
[1] - V.M. Lipunov, V.G. Kornilov, E.S. Gorbovskoy, N.A. Tiurina & A.S.Kuznetsov, 2023, Astronomical Robotic Networks and Operative Multichanel Astrophysics, Lomonosov MSU PRESS, 591pp.
http : // www.pereplet.ru/lipunov/625.html