GRB 260207A
GCN Circular 43936
Subject
GRB 260207A: TESS Detection and Possible VLA Counterpart
Date
2026-03-06T18:35:15Z (5 days ago)
From
Sarah Chastain at Texas Tech University <sarahichastain@gmail.com>
Via
Web form
S. I Chastain (TTU) and M. M. Fausnaugh (TTU) report:
Approximately 93% of the Fermi GBM localization of GRB 260207A (Fermi GBM Team, GCN 43628) fell within the field of view of the Transiting Exoplanet Survey Satellite (TESS; Ricker et al. JATIS 1 2015) during observations of sector 100.
We identified a counterpart consistent with the counterpart reported by MASTER-OT (C. Francile et al., GCN 43633).
At around 14 days post-burst, we carried out VLA observations of this counterpart and identified a faint source within the error region with a flux of 24 +/- 4 microJy/BM at 6 GHz.
The position of this source is:
RA (J2000): 10:44:11.3314 ± 0.0016 seconds
Declination (J2000): -33:09:36.053 ± 0.067 arcseconds
This circular includes data collected with the TESS mission, obtained from the MAST data archive at the Space Telescope Science Institute (STScI). Funding for the TESS mission is provided by the NASA Explorer Program. STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555.
These observations were carried out as part of project SF171128,
approved in the framework of the Fermi - NRAO joint program agreement.
GCN Circular 43633
Subject
GRB 260207A : MASTER optical counterpart discovery
Date
2026-02-07T19:42:05Z (a month ago)
Edited On
2026-02-09T14:26:53Z (a month ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Vladimir Lipunov at Lomonosov Moscow State University <lipunov@sai.msu.ru>
Via
email
C. Francile (OAFA), O.Gress (ISU), V.M.Lipunov (Lomonosov MSU), R.Podesta, F.Podesta (OAFA),
D.Svinkin, A.Ridnaya (Ioffe Institute),
I.Panchenko, P.Balanutsa, G.Antipov, A.Kuznetsov, E.Gorbovskoy, N. Tiurina, Ya.Kechin,A.Chasovnikov,
V.A.Senik, D.Vlasenko, I.Ionov,Yu.Tselik(Lomonosov MSU),
N.Budnev, R.Mirgazov, A.Diachok, O.Ershova (Irkutsk State University),
E. Gonzalez (OAFA, San JuanUni.,Argentina);
D.Buckley (SAAO),
A. Sosnovskij (CrAO RAS),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino, J.Martinez, A.R.Corella, J.G.
Tanori, L. F. Villalobos, L.H.Rodriguez (INAOE, Guillermo Haro AstrophysicObservatory, Mexico)
V.M.Pillet, R.Rebolo Lopez (The Instituto de Astrofisica de Canarias,Spain)
MASTER Global Robotic Net started (Lipunov et al. GCN 43627) Fermi GRB 260207A (GCN 43628)
alert observtions at MASTER-OAFA 110 sec after notice time and 142 sec after trigger time at 2026-02-07 05:44:56 UT
MASTER OT J104411.31-330936.2 discovery
MASTER-OAFA auto-detection system ( Lipunov et al., "MASTER Global Robotic Net", Advances in Astronomy, 2010, 30L )
discovered OT source at (RA, Dec) = 10h 44m 11.31s -33d 09m 36.2s on 2026-02-07.24049 UT.
The OT unfiltered magnitude was 17.3m(mlim19.8=).
The OT is seen in 27 images with typical decay with different features at light curves.
There is no minor planet at this place.
We have reference image on 2025-02-08.36365 UT with unfiltered 20.1m.
Deep photometry and spectral observations are required.
We reobserved these coordinates at MASTER-SAAO at 2026-02-07 18:59:00 without object, that confirmed GRB optical counterpart nature
GCN Circular 43628
Subject
GRB 260207A: Fermi GBM Final Localization
Date
2026-02-07T06:32:02Z (a month ago)
From
Rushikesh Sonawane at IISER, TVM <rushikesh23@iisertvm.ac.in>
Via
Web form
The Fermi GBM team reports the detection of a likely LONG GRB
"At 05:42:33.65 UT on 07 February 2026, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 260207A (trigger 792135758/260207238).
The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 160.45, Dec = -34.44 (J2000 degrees, equivalent to J2000 10h 41m, -34d 26'),
with a statistical uncertainty of 3.29 degrees.
The angle from the Fermi LAT boresight is 37 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260207238/quicklook/glg_skymap_all_bn260207238.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/bn260207238/quicklook/glg_healpix_all_bn260207238.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260207238/quicklook/glg_lc_medres34_bn260207238.gif"
GCN Circular 43627
Subject
Fermi trigger No 792135758: Global MASTER-Net observations report
Date
2026-02-07T06:16:25Z (a month ago)
Edited On
2026-02-09T14:27:14Z (a month ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Vladimir Lipunov at Lomonosov Moscow State University <lipunov@sai.msu.ru>
Via
email
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 GRB260207.24 (trigger No 792135758,10h 41m 48.00s , -34d 26m 24.0s, R=3.29) errorbox 110 sec after notice time and 142 sec after trigger time at 2026-02-07 05:44:56 UT, with upper limit up to 20.7 mag. The observations began at zenith distance = 7 deg. The sun altitude is -41.7 deg.
The galactic latitude b = 21 deg., longitude l = 275 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=3124959
We obtain a following upper limits.
Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
158 | 2026-02-07 05:44:56 | MASTER-OAFA | (10h 51m 33.24s , -33d 38m 46.3s) | C | 30 | 19.5 |
203 | 2026-02-07 05:44:56 | MASTER-OAFA | (10h 51m 33.24s , -33d 38m 46.4s) | C | 120 | 20.0 | Coadd
198 | 2026-02-07 05:45:32 | MASTER-OAFA | (10h 51m 33.30s , -33d 38m 44.9s) | C | 40 | 19.6 |
250 | 2026-02-07 05:46:18 | MASTER-OAFA | (10h 51m 33.38s , -33d 38m 43.0s) | C | 50 | 19.7 |
311 | 2026-02-07 05:47:14 | MASTER-OAFA | (10h 51m 33.48s , -33d 38m 40.8s) | C | 60 | 19.8 |
382 | 2026-02-07 05:48:20 | MASTER-OAFA | (10h 51m 33.59s , -33d 38m 38.3s) | C | 70 | 19.8 |
644 | 2026-02-07 05:52:17 | MASTER-OAFA | (10h 42m 03.76s , -34d 05m 23.7s) | C | 120 | 19.9 |
799 | 2026-02-07 05:52:17 | MASTER-OAFA | (10h 42m 03.76s , -34d 05m 23.7s) | C | 430 | 20.7 | Coadd
781 | 2026-02-07 05:54:24 | MASTER-OAFA | (10h 42m 04.00s , -34d 05m 19.4s) | C | 140 | 19.9 |
942 | 2026-02-07 05:56:50 | MASTER-OAFA | (10h 42m 04.28s , -34d 05m 14.5s) | C | 170 | 19.9 |
1064 | 2026-02-07 05:59:47 | MASTER-OAFA | (10h 42m 04.50s , -34d 05m 10.9s) | C | 60 | 19.7 |
1129 | 2026-02-07 06:00:52 | MASTER-OAFA | (10h 42m 04.62s , -34d 05m 08.8s) | C | 60 | 19.7 |
1194 | 2026-02-07 06:01:58 | MASTER-OAFA | (10h 42m 04.73s , -34d 05m 07.0s) | C | 60 | 19.7 |
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