GCN 44098: Fermi GRB 260323A: Global MASTER-Net observations report
2026-03-24T00:15:25.035Z | rev 0
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, I. Gorbunov (Lomonosov MSU),
O.Gress, N.Budnev (ISU),
C.Francile, F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A.Sosnovskij (CrAO),
A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity),
D.Buckley (SAAO),
R.Rebolo (The Instituto de Astrofisica de Canarias),
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory)
MASTER-OAFA robotic telescope [1] located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 260323A ( Fermi GBM team, GCN 44097) errorbox 143 sec after notice time and 173 sec after trigger time at 2026-03-23 23:54:21 UT, with upper limit up to 20.1 mag. Observations started at twilight. The observations began at zenith distance = 43 deg. The sun altitude is -16.3 deg.
The galactic latitude b = -27 deg., longitude l = 289 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=3206970
We obtain a following upper limits.
Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
188 | 2026-03-23 23:54:21 | MASTER-OAFA | (06h 02m 40.77s , -72d 38m 38.2s) | C | 30 | 18.8 |
229 | 2026-03-23 23:54:57 | MASTER-OAFA | (06h 02m 40.97s , -72d 38m 38.5s) | C | 40 | 18.9 |
280 | 2026-03-23 23:55:43 | MASTER-OAFA | (06h 02m 41.22s , -72d 38m 38.9s) | C | 50 | 19.2 |
341 | 2026-03-23 23:56:39 | MASTER-OAFA | (06h 02m 41.55s , -72d 38m 39.0s) | C | 60 | 19.3 |
650 | 2026-03-24 00:01:17 | MASTER-OAFA | (06h 42m 20.00s , -76d 51m 39.3s) | C | 120 | 20.1 |
786 | 2026-03-24 00:03:23 | MASTER-OAFA | (06h 42m 20.80s , -76d 51m 40.5s) | C | 140 | 20.1 |
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
GCN 44097: GRB 260323A: Fermi GBM Final Real-time Localization
2026-03-24T00:02:09.834Z | rev 0
The Fermi GBM team reports the detection of a likely LONG GRB
At 23:51:27 UT on 23 Mar 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260323A (trigger 796002692.989066 / 260323994).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 100.1, Dec = -77.1 (J2000 degrees, equivalent to J2000 06h 40m, -77d 05'), with a statistical uncertainty of 5.5 degrees.
The angle from the Fermi LAT boresight is 149.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260323994/quicklook/glg_skymap_all_bn260323994.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260323994/quicklook/glg_healpix_all_bn260323994.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260323994/quicklook/glg_lc_medres34_bn260323994.gif