January 2026 - vsnet-grb-info - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-grb-info 41619] Fermi-LAT Gamma-ray Observations of IceCube-260125A
by GCN Circulars 26 Jan '26

26 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43519 SUBJECT: Fermi-LAT Gamma-ray Observations of IceCube-260125A DATE: 26/01/26 21:49:24 GMT FROM: Leo Pfeiffer at University of Würzburg <pfeiffer.leo(a)gmail.com> L. Pfeiffer (Univ. of Wuerzburg), S. Buson (DESY, Univ. of Wuerzburg) and S. Garrappa (Weizmann Institute of Science) on behalf of the Fermi-LAT collaboration: We report an analysis of observations of the vicinity of the high-energy IC260125A neutrino event (GCN 43512) with all-sky survey data from the Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope. The IceCube event was detected on 2026-01-25 at 10:09:39.88 UTC (T0) with J2000 position RA = 243.72 (+0.52, -0.56) deg, Decl. = 6.69 (+0.62, -0.61) deg 90% PSF containment (J2000). No cataloged gamma-ray sources are found within the 90% IC260125A localization error (4FGL-DR4; The Fourth Fermi-LAT catalog Data Release 4, The Fermi-LAT collaboration 2023, arXiv:2307.12546). We searched for the existence of intermediate (days to years) timescale emission from a new gamma-ray transient source. Preliminary analysis indicates no significant (>5sigma) new excess emission (> 100 MeV) within the IC260125A 90% confidence localization. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IC260125A best-fit position, the >100 MeV flux upper limit (95% confidence) is < 1.4e-10 ph cm^-2 s^-1 for ~17-years (2008-08-04 / T0), <5.3e-09 (<8.8e-08) ph cm^-2 s^-1 for a 1-month (1-day) integration time before T0. Since Fermi normally operates in an all-sky scanning mode, regular monitoring of this source will continue. For this analysis, the Fermi-LAT contact person is L. Pfeiffer (leonard.pfeiffer at uni-wuerzburg.de). The Fermi LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden. View this GCN Circular online at https://gcn.nasa.gov/circulars/43519. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41618] GRB 260125A: NOT optical observations on GOTO26acv / AT 2026bjf
by GCN Circulars 26 Jan '26

26 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43518 SUBJECT: GRB 260125A: NOT optical observations on GOTO26acv / AT 2026bjf DATE: 26/01/26 14:19:11 GMT FROM: Daniele Bjørn Malesani at Cosmic Dawn Center, Niels Bohr Institute <daniele.malesani(a)nbi.ku.dk> D. B. Malesani (DAWN/NBI and Radboud), B. P. Gompertz (Birmingham), G. Corcoran (UCD), L. Izzo (INAF/OAC and DARK/NBI), A. Martin-Carrillo (UCD), S. Bijavara Seshashayana (NOT), report on behalf of a larger collaboration: We observed the optical candidate GOTO26acv / AT 2026bjf (Gompertz et al., GCN 43514) of the Fermi GRB 260125A (Fermi GBM team, GCN 43510) using the Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. Observations were carried out using the SDSS griz filters, and started on 2026 Jan 25.995 UT (16.27 hr after the Fermi/GBM trigger). Visual inspection reveals no obvious point source at the coordinates of GOTO26acv / AT 2026bjf, on top of the galaxy PGC 139241 (LEDA 139241), in any of the observed bands, though we note that the bright and complex morphology of the galaxy makes a clear identification tough. Image subtraction against the Legacy survey archival images yields an upper limit r > 22.75 (AB) at a mean time of 16.47 hr after trigger (5x150 s exposure time). This value is calibrated against the Pan-STARRS catalog and is not corrected for Galactic extinction. Our limit is notionally deeper than the extrapolation of the power-law decay reported by Gompertz et al. (GCN 43514), even after accounting for a GOTO/ALFOSC color term and the quoted decay index uncertainty. View this GCN Circular online at https://gcn.nasa.gov/circulars/43518. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41617] Konus-Wind detection of GRB 260120B
by GCN Circulars 26 Jan '26

26 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43517 SUBJECT: Konus-Wind detection of GRB 260120B DATE: 26/01/26 13:06:35 GMT FROM: Anna Ridnaia at Ioffe Institute <ridnaia(a)mail.ioffe.ru> A. Ridnaia, D. Frederiks, A. Lysenko, D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline, on behalf of the Konus-Wind team, report: The long-duration GRB 260120B (Fermi GBM detection: Fermi GBM team, GCN 43477; Godwin & Meegan, GCN 43489; Swift-BAT detection: Ferro et al., GCN 43479; Palmer et al., GCN 43493; AstroSat CZTI detection: Goyal et al., GCN 43504) triggered Konus-Wind at T0=64826.649 s UT (18:00:26.649). The burst light curve shows a single pulse, which starts at ~T0-3.2 s and has a total duration of ~5.9 s. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB260120_T64826/ As observed by Konus-Wind, the burst had a fluence of 3.41(-0.52,+0.58)x10^-6 erg/cm2, and a 64-ms peak flux, measured from T0-0.064 s, of 1.97(-0.58,+0.60)x10^-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range). Since a major part of the burst emission was detected before the trigger, the spectral analysis was performed using the KW 3-channel light curve data. Modelling the KW 3-channel time-integrated spectrum (measured from T0-3.173 s to T0+2.720 s) by a power law with exponential cutoff (CPL) model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep), yields alpha = -0.56(-0.23,+0.30) and Ep = 246(-53,+67) keV. All the quoted errors are at the 68% confidence level. All the quoted values are preliminary. View this GCN Circular online at https://gcn.nasa.gov/circulars/43517. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41616] GRB 251222A: SVOM/ECLAIRs refined analysis
by GCN Circulars 26 Jan '26

26 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43516 SUBJECT: GRB 251222A: SVOM/ECLAIRs refined analysis DATE: 26/01/26 11:12:41 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> Hui Yang, Sebastien Guillot, Olivier Godet, Marius Brunet, Guangxuan Lan (IRAP) Using the event-by-event data downloaded through the X-band ground station, we report further analysis of ECLAIRs observations of GRB 251222A (SVOM burst-id sb25122206, GCN 43188). The burst that triggered ECLAIRs consists of multiple peaks, and is detected for more than 200 s in the 4-120 keV energy band. The time-averaged spectrum before the slew from T0-14 s to T0+37 s (T0 = 2025-12-22T17:05:46) in the energy range 5-120 keV is best fitted by a cutoff power-law model with a photon index of 1.3+/-0.1, an Ecut of 54(+29/-15) keV, giving a corresponding 4-120 keV flux of (4.9+/-0.3)e-8 erg/cm^2/s. The spectrum from T0+162 s to T0+192 s after the slew in the energy range 5-120 keV is well fitted by a power-law model with a photon index of 2.4 +/-0.2 giving a corresponding 4-120 keV flux of (9+/-1)e-9 erg/cm^2/s. All the quoted errors are at the 68% confidence level. The Space-based multi-band astronomical Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA), French Space Agency (CNES), and the Chinese Academy of Sciences (CAS), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. ECLAIRs was developed jointly by CNES, CEA-IRFU, CNRS-IRAP, CNRS-APC. The SVOM/ECLAIRs point of contact for this burst is: Hui Yang (IRAP) (hyang(a)irap.omp.eu) View this GCN Circular online at https://gcn.nasa.gov/circulars/43516. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41615] GRB 260125A: Swift ToO observations
by GCN Circulars 26 Jan '26

26 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43515 SUBJECT: GRB 260125A: Swift ToO observations DATE: 26/01/26 02:44:30 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> P. A. Evans (U. Leicester) reports on behalf of the Swift team: Swift has initiated a ToO observation of the Fermi/GBM-detected event GRB 260125A. Automated analysis of the XRT data will be presented online at https://www.swift.ac.uk/ToO_GRBs/00021899 Any uncatalogued X-ray sources detected in this analysis will be reported on this website and via GCN COUNTERPART notices. These are not necessarily related to the Fermi/GBM event. Any X-ray source considered to be a probable afterglow candidate will be reported via a GCN Circular after manual consideration. Details of the XRT automated analysis methods are detailed in Evans et al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8). This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/43515. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41614] GRB 260125A: GOTO candidate optical counterpart
by GCN Circulars 25 Jan '26

25 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43514 SUBJECT: GRB 260125A: GOTO candidate optical counterpart DATE: 26/01/25 20:20:30 GMT FROM: Ben Gompertz at U of Birmingham <b.gompertz(a)bham.ac.uk> B. P. Gompertz, S. Moran, D. O’Neill, R. Starling, K. Ackley, M. Dyer, J. Lyman, K. Ulaczyk, D. Steeghs, D. Galloway, V. Dhillon, P. O'Brien, G. Ramsay, K. Noysena, R. Kotak, R. Breton, J. Casares, L. Nuttall, B. Godson, T. Killestein, A. Kumar, M. Pursiainen report on behalf of GOTO collaboration: We report on optical observations with the Gravitational-wave Optical Transient Observer (GOTO; Steeghs et al. 2022, Dyer et al. 2024) in response to the GRB 260125A (Fermi GBM Team, GCN 43510). Observations from GOTO-South (Siding Spring) covering the localisation area began at 2026-01-25 12:06:29 UT (+4.49h post trigger) and continued through to 2026-01-25 15:46:04 UT (+8.54h post trigger). 292 images were taken, across 16 unique pointings, covering 510.2 within the 90% localisation contour. ~78.0% of the total 2D localisation probability was covered, with an average 5-sigma depth of 20.8 mag. Images were processed immediately after acquisition using the GOTO pipeline. Difference imaging was performed using deeper template observations. Source candidates were initially filtered using a classifier (Killestein et al. 2021) and cross-matched against a variety of contextual and minor planet catalogs. Human vetting was carried out in real time on any candidates that passed the above checks. Within the 90% probability region, we identify a new transient, GOTO26acv (AT 2026bjf), lying on the 20th percentile contour of the GBM localisation map at coordinates: RA = 10:06:16.71, Dec = -06:34:33.55 (J2000), equivalent to RA = 151.56962, Dec = -6.57599 degrees. GOTO26acv / AT 2026bjf was discovered with an AB magnitude of L = 20.17 ± 0.16 in an epoch taken at 12:29:25 UT, i.e. 4.87h post-trigger. Across three epochs of detection, it was observed to fade by 0.42 ± 0.25 magnitudes in 2.35 hours, equivalent to a power-law decay rate of t^-0.92 ± 0.38. The final detection magnitude was L = 20.59 ± 0.19 at 14:50:26 UT. The source is spatially coincident with the galaxy PGC 139241 at a luminosity distance of 53 Mpc. It is offset from the nucleus by ~9”. The source was not present in the most recent survey image of the field, taken at 13:37:58 UT on 2026-01-24 (0.75 days prior to the GRB trigger), to a 3-sigma limiting magnitude of L > 20.95. We also find no evidence of GOTO26acv / AT 2026bjf prior to the GRB trigger time in the ZTF observations provided by the Lasair broker (Smith et al. 2019), or the ATLAS forced photometry server (Shingles et al. 2021). Further follow-up observations to establish the nature of GOTO26acv / AT2026bjf and its potential association with GRB 260125A are encouraged. Magnitudes were calibrated using ATLAS-REFCAT2 (Tonry et al. 2018) and not corrected for Galactic extinction. GOTO (https://goto-observatory.org) is a network of telescopes that is principally funded by the STFC and operated at the Roque de los Muchachos Observatory on La Palma, Spain, and Siding Spring Observatory in NSW, Australia, on behalf of a consortium including the University of Warwick, Monash University, Armagh Observatory & Planetarium, the University of Leicester, the University of Sheffield, the National Astronomical Research Institute of Thailand (NARIT), the University of Turku, the University of Portsmouth, the University of Manchester, the University of Birmingham and the Instituto de Astrofisica de Canarias (IAC). View this GCN Circular online at https://gcn.nasa.gov/circulars/43514. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41613] Fermi GRB 260125B: Global MASTER-Net observations report
by GCN Circulars 25 Jan '26

25 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43513 SUBJECT: Fermi GRB 260125B: Global MASTER-Net observations report DATE: 26/01/25 11:45:33 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov(a)xray.sai.msu.ru> 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-Tunka robotic telescope [1] located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB 260125B ( Fermi GBM team, GCN 43511) errorbox 3759 sec after notice time and 3791 sec after trigger time at 2026-01-25 11:28:56 UT, with upper limit up to 18.4 mag. Observations started at twilight. The observations began at zenith distance = 43 deg. The sun altitude is -16.2 deg. The galactic latitude b = -13 deg., longitude l = 185 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3114740 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 3821 | 2026-01-25 11:28:56 | MASTER-Tunka | (05h 18m 03.87s , +20d 44m 22.3s) | C | 60 | 18.4 | 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 View this GCN Circular online at https://gcn.nasa.gov/circulars/43513. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41612] Fermi GRB 260125B: Global MASTER-Net observations report
by GCN Circulars 25 Jan '26

25 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43513 SUBJECT: Fermi GRB 260125B: Global MASTER-Net observations report DATE: 26/01/25 11:45:33 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov(a)xray.sai.msu.ru> 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-Tunka robotic telescope [1] located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB 260125B ( Fermi GBM team, GCN 43511) errorbox 3759 sec after notice time and 3791 sec after trigger time at 2026-01-25 11:28:56 UT, with upper limit up to 18.4 mag. Observations started at twilight. The observations began at zenith distance = 43 deg. The sun altitude is -16.2 deg. The galactic latitude b = -13 deg., longitude l = 185 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3114740 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 3821 | 2026-01-25 11:28:56 | MASTER-Tunka | (05h 18m 03.87s , +20d 44m 22.3s) | C | 60 | 18.4 | 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 View this GCN Circular online at https://gcn.nasa.gov/circulars/43513. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41611] IceCube-260125A - IceCube observation of a high-energy neutrino candidate track-like event
by GCN Circulars 25 Jan '26

25 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43512 SUBJECT: IceCube-260125A - IceCube observation of a high-energy neutrino candidate track-like event DATE: 26/01/25 11:33:55 GMT FROM: A. Zegarelli at Ruhr University Bochum <azegarelli(a)icecube.wisc.edu> The IceCube Collaboration (http://icecube.wisc.edu/) reports: On 26-01-25 at 10:09:39.88 UT IceCube detected a track-like event with a moderate probability of being of astrophysical origin. The event was selected by the ICECUBE_Astrotrack_BRONZE alert stream. The average astrophysical neutrino purity for Bronze alerts is 30%. This alert has an estimated false alarm rate of 1.9783 events per year due to atmospheric backgrounds. The IceCube detector was in a normal operating state at the time of detection. After the initial automated alert (https://gcn.gsfc.nasa.gov/notices_amon_g_b/141985_63695019.amon) more sophisticated reconstruction algorithms have been applied offline, with the direction refined to: Date: 26-01-25 Time: 10:09:39.88 UT RA: 243.72 (+0.52/-0.56 deg 90% PSF containment) J2000 Dec: 6.69 (+0.62/-0.61 deg 90% PSF containment) J2000 As announced in GCN Circular 43419, IceCube alert notices for high-energy track alerts are now also streamed via Kafka. IceCube Gold/Bronze track alerts are available on the Kafka topic 'gcn.notices.icecube.gold_bronze_track_alerts'. The probability distribution of the true neutrino direction, allowing the extraction of precise 90% containment regions around the best-fit direction, is now available for revised reconstruction of high-energy track alerts. The corresponding sky map is distributed as a FITS file and follows the explicit naming convention IceCube-YYMMDDX (e.g. IceCube-260125A, for this alert), where YYMMDD indicates the date of the event and X is a letter distinguishing multiple alerts on the same day. The download link (e.g., for this alert https://roc-2.icecube.wisc.edu/public/alerts/IceCube-260125A_skymap_probden…) is provided through the GCN schema distributed via Kafka. Additional information will be soon available at https://gcn.nasa.gov/missions/icecube. In the near future, classical GCN stream will be deactivated. No known gamma-ray sources listed in the Fermi 4FGL-DR4 or 3FHL catalogs are located within the 90% uncertainty region of this event. The IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc(a)icecube.wisc.edu View this GCN Circular online at https://gcn.nasa.gov/circulars/43512. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41610] GRB 260125B: Fermi GBM Final Real-time Localization
by GCN Circulars 25 Jan '26

25 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43511 SUBJECT: GRB 260125B: Fermi GBM Final Real-time Localization DATE: 26/01/25 10:36:26 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply(a)GIOC.nsstc.nasa.gov> The Fermi GBM team reports the detection of a likely LONG GRB At 10:25:45 UT on 25 Jan 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260125B (trigger 791029550.226442 / 260125435). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 77.1, Dec = 17.6 (J2000 degrees, equivalent to J2000 05h 08m, 17d 36'), with a statistical uncertainty of 11.6 degrees. The angle from the Fermi LAT boresight is 28.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260125435/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260125435/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260125435/… View this GCN Circular online at https://gcn.nasa.gov/circulars/43511. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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