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[vsnet-grb-info 43010] GRB 260604C: further SAO RAS optical observations
by GCN Circulars 08 Jun '26

08 Jun '26

TITLE: GCN CIRCULAR NUMBER: 44877 SUBJECT: GRB 260604C: further SAO RAS optical observations DATE: 26/06/08 22:27:43 GMT FROM: Alexander Moskvitin at SAO RAS <mosk(a)sao.ru> A. Moskvitin (SAO RAS), O. Spiridonova (SAO RAS), A. Pozanenko (IKI), A. Volnova (IKI), N. Pankov (IKI) report on behalf of GRB follow-up team We observed the field of long GRB 260604C discovered by Fermi (The Fermi GBM team, GCN 44822; Neights & Meegan, GCN 44831); SVOM (Gotz et al., GCN 44823) and GECAM-B (Luo et al., GCN 44854) with the Zeiss-1000 1-m telescope of SAO RAS equipped with the CCD photometer. We obtained 12 x 300 sec. images in Rc band on June 08, 20:01:14--21:07:58 UT. The OT (Lipunov, GCN 44827; Konno et al., GCN 44828; GCN 44836; Zhu et al., GCN 44832; Becerra et al., GCN 44834; Hellot et al., GCN 44835; Gompertz et al., GCN 44837; Gompertz et al., GCN 44843; Chen et al., GCN 44851; Moskvitin et al., GCN 44852; Sasaki et al., GCN 44857; Pankov et al., GCN 44858; Pankov et al., GCN 44862; Burkhonov et al., GCN 44865; Lincetto et al., GCN 44873) is detected in our stacked image with the following brightness: Date UTstart t-T0 Exp. Filter Mag +/- Err. UL (mid,d) (n*s) (3-sigma) 2026.06.08 20:01:14 4.01102 12*300 Rc 23.08 +/- 0.18 23.8 The preliminary photometry is based on nearby SDSS stars (R-magnitudes were obtained using Lupton 2005 transformation equations) as in Moskvitin et al., GCN 44852, and was not corrected for the Galactic extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/44877. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43009] GRB 260607A: AT2026ong (GOTO26fqf) is a type-Ia SN
by GCN Circulars 08 Jun '26

08 Jun '26

TITLE: GCN CIRCULAR NUMBER: 44876 SUBJECT: GRB 260607A: AT2026ong (GOTO26fqf) is a type-Ia SN DATE: 26/06/08 18:46:23 GMT FROM: Daniele Bjørn Malesani at Cosmic Dawn Center, Niels Bohr Institute <daniele.malesani(a)nbi.ku.dk> G. Corcoran (UCD), L. Izzo (INAF/OAC and DARK/NBI), B. Schneider (LAM), J. An (NAOC), B. P. Gompertz (Birmingham), V. Abril-Melgarejo (LUX-Paris Obs.), D. B. Malesani (DAWN/NBI and Radboud) report on behalf of the Stargate collaboration: We observed the transient AT2026ong (GOTO26fqf; Gompertz et al., GCN 44864; He et al., GCN 44866; Lincetto et al., GCN 44875), proposed to be associated with the Fermi GBM GRB 260607A (Fermi GBM team, GCN 44855) using the ESO Very Large Telescope (VLT) UT3 (Melipal) equipped with the X-shooter telescope. Our spectra cover the wavelength range 3000-25000 AA, and consist of 2 exposures of 600 s each. The observation mid time was 2026 Jun 8.40 UT (20.87 hr after the GRB). In the acquisition image, we measure an AB magnitude r = 19.49 +- 0.03 (calibrated against Pan-STARRS, not corrected for Galactic extinction). The slit also covers the galaxy just east of the transient (Gompertz et al., GCN 44864), its likely host galaxy. From detection of multiple emission (Halpha, [N II], [S II]) and absorption (Ca II, G band) features, we measure for the galaxy a redshift of z = 0.111. The spectrum of the transient reveals a clear continuum with broad undulations across the entire optical range, markedly different from GRB afterglow spectra. Template matching via SNID-SAGE (Stoppa et al. 2026, doi:10.48550/arXiv.2603.28741) indicates a good agreement with a type-Ia SN, at a redshift consistent with the galaxy redshift. GOTO26fqf is thus not related to GRB 260607A and has been now named SN 2026ong. The UVB and VIS spectra of the transient are available via TNS at https://www.wis-tns.org/object/2026ong. We acknowledge excellent support from the ESO observing staff in Paranal, in particular Celia Desgrange and Francisco Caceres, for rapidly executing these observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/44876. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43008] GRB 260607A / GOTO26fqf / AT2026ong: COLIBRÍ optical observations
by GCN Circulars 08 Jun '26

08 Jun '26

TITLE: GCN CIRCULAR NUMBER: 44875 SUBJECT: GRB 260607A / GOTO26fqf / AT2026ong: COLIBRÍ optical observations DATE: 26/06/08 18:24:05 GMT FROM: Massimiliano Lincetto at Aix Marseille Univ, CNRS/IN2P3, CPPM <lincetto(a)cppm.in2p3.fr> Massimiliano Lincetto (CPPM), Leonardo García García (UNAM), Jean-Grégoire Ducoin (CPPM), Benjamin Schneider (LAM), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Alan M. Watson (UNAM), Edilberto Aguilar-Ruiz (UNAM), Jean-Luc Atteia (IRAP), Camila Angulo (UNAM), Dalya Akl (NYUAD), Sarah Antier (IJCLAB), Rosa L. Becerra (UNAM), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Francis Fortin (IRAP), Ramandeep Gill (UNAM), Noémie Globus (UNAM), Marion Guelfand (CPPM), Asuka Kuwata (UNAM), Nikos Mandarakas (LAM), Diego López-Cámara (UNAM), Francesco Magnani (CPPM), Enrique Moreno Méndez (UNAM), Margarita Pereyra (UNAM), Ny Avo Rakotondrainibe (LAM), Fredd Sánchez Álvarez (UNAM) and Antonio de Ugarte Postigo (LAM) report: We imaged the candidate optical counterpart GOTO26fqf / AT2026ong (Gompertz et al., GCN Circ. 44864) of the Fermi GRB 260607A (Fermi GBM, GCN Circ. 44855) using the DDRAGO two-channel wide-field imager on the COLIBRÍ telescope. We observed from 2026-06-08 09:42 to 09:58 UTC (23 hours after the trigger) and obtained 840 seconds of simultaneous exposure in the r/z filters. The data were reduced and coadded with the COLIBRÍ ASU pipeline and analysed in STDWeb/STDPipe (Karpov 2025). The photometry was calibrated using nearby stars from the PanSTARRS DR1 catalog, is in the AB system, and is not corrected for Galactic extinction. After subtracting template Pan-STARRS images, we detected the optical counterpart reported by Gompertz et al., GCN Circ. 44864, at preliminary magnitudes of: r = 19.72 +/- 0.01 z = 20.05 +/- 0.04 The measurement is consistent with a no-evolution scenario with reference to the GOTO measurement taken 14.7h after the trigger. The color r-z = -0.33 indicates a blue object, not consistent with typical GRB afterglows. We thank the staff of the Observatorio Astronómico Nacional at Sierra de San Pedro Mártir, as well as the technical and engineering teams at CEA, CPPM, IRAP, LAM, OHP, OSU Pytheas, and UNAM. COLIBRÍ is an astronomical observatory developed and operated jointly by France (AMU, CNES and CNRS) and Mexico (UNAM and SECIHTI). It is located at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir, Baja California, Mexico. View this GCN Circular online at https://gcn.nasa.gov/circulars/44875. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43007] GRB 260608B: Fermi GBM Final Localization
by GCN Circulars 08 Jun '26

08 Jun '26

TITLE: GCN CIRCULAR NUMBER: 44874 SUBJECT: GRB 260608B: Fermi GBM Final Localization DATE: 26/06/08 17:54:52 GMT FROM: oindabimukherjee(a)gmail.com The Fermi GBM team reports the detection of a likely LONG GRB "At 12:41:28.68 UT on 08 June 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260608B (trigger 802615293/260608529). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 56.98, Dec = 64.15 (J2000 degrees, equivalent to J2000 3h 47m, +64d 9'), with a statistical uncertainty of 3.78 degrees. The angle from the Fermi LAT boresight is 116 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260608529/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260608529/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260608529/…" View this GCN Circular online at https://gcn.nasa.gov/circulars/44874. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43006] GRB 260604C: SVOM/COLIBRÍ (FM-GFT) colour evolution and confirmation of the late rebrightening
by GCN Circulars 08 Jun '26

08 Jun '26

TITLE: GCN CIRCULAR NUMBER: 44873 SUBJECT: GRB 260604C: SVOM/COLIBRÍ (FM-GFT) colour evolution and confirmation of the late rebrightening DATE: 26/06/08 15:49:40 GMT FROM: Rosa Leticia Becerra Godínez at Instituto de Astronomía, UNAM <rbecerra(a)astro.unam.mx> Massimiliano Lincetto (CPPM), Leonardo García García (UNAM), Rosa L. Becerra (UNAM), Antonio de Ugarte Postigo (LAM), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Alan M. Watson (UNAM), Sarah Antier (IJCLAB), Edilberto Aguilar-Ruiz (UNAM), Jean-Luc Atteia (IRAP), Camila Angulo (UNAM), Dalya Akl (NYUAD), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Jean-Grégoire Ducoin (CPPM), Francis Fortin (IRAP), Ramandeep Gill (UNAM), Noémie Globus (UNAM), Marion Guelfand (CPPM), Asuka Kuwata (UNAM), Nikos Mandarakas (LAM), Diego López-Cámara (UNAM), Francesco Magnani (CPPM), Enrique Moreno Méndez (UNAM), Margarita Pereyra (UNAM), Ny Avo Rakotondrainibe (LAM), Fredd Sánchez Álvarez (UNAM), Benjamin Schneider (LAM), and Sofia Bisero (CEA Saclay) report: We re-imaged the field of GRB 260604C (Fermi GBM Team, GCN Circ. 44822, Gotz et al., GCN Circ. 44823) using the DDRAGO two-channel wide-field imager on the COLIBRÍ telescope. We observed from 2026-06-08 06:37 to 09:24 UTC (from 3.43 to 3.54 days after the trigger) and obtained 64, 63, and 127 minutes of exposure in the g, r, and z filters respectively. The data were reduced, coadded and analysed with the ASU COLIBRÍ pipeline. The photometry was calibrated using nearby stars from the PanSTARRS DR1 catalog, is in the AB system, and is not corrected for Galactic extinction. In our first epoch reported by Becerra et al. (GCN Circ. 44827), we measured: g-r = 0.13 +/- 0.07 g-z = 0.48 +/- 0.10 In this epoch, we measured: g-r = 0.47 +/- 0.06 g-z = 0.86 +/- 0.09 Our measurements indicate a significant reddening of the source between the two epochs. Moreover, we also observe the rebrightening first reported by the Mondy team (Pankov et al., GCN Circ. 44862). The rise began approximately 30 hours after the trigger and lasted for about 30 hours. Further observations and analysis are ongoing. We thank the staff of the Observatorio Astronómico Nacional at Sierra de San Pedro Mártir, as well as the technical and engineering teams at CEA, CPPM, IRAP, LAM, OHP, OSU Pytheas, and UNAM. COLIBRÍ is an astronomical observatory developed and operated jointly by France (AMU, CNES and CNRS) and Mexico (UNAM and SECIHTI). It is located at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir, Baja California, Mexico. View this GCN Circular online at https://gcn.nasa.gov/circulars/44873. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43005] GRB 260604C: SVOM/C-GFT upper limit
by GCN Circulars 08 Jun '26

08 Jun '26

TITLE: GCN CIRCULAR NUMBER: 44872 SUBJECT: GRB 260604C: SVOM/C-GFT upper limit DATE: 26/06/08 15:20:05 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> C. Wu (NAOC), Z. Kang (CHO), L.P. Xin（NAOC), S.J. Yin (GXU), X.H. Han, P.P. Zhang, X.M. Lu (NAOC), Z.W. Li, Y. Lv (CHO), R.S. Zhang, Y.J. Xiao, Y.L. Qiu, J. Wang, J.S. Deng, L. Huang, J.Y. Wei (NAOC), N. Dagoneau, S. Bisero (CEA Saclay) report on behalf of the SVOM/C-GFT team: We observed the field of GRB 260604C (SVOM burst-id sb26060404) detected by SVOM/ECLAIRs (GCN 44823) with LATIOS on SVOM/C-GFT. Observations started at 2026-06-05T15:54:29 UTC, ~19.54 h after the trigger. We obtained 9X90s exposures in the SDSS g filter. After preliminary analysis，we do not detect the optical counterpart (Lipunov et al., GCN 44827; Konno et al., GCN 44828; Zhu et al., GCN 44832, Becerra et al., GCN 44834; Hellot et al., GCN 44835; Gompertz et al., GCN 44837; Gompertz et al., GCN 44843; Saccardi et al., GCN 44844; Chen et al., GCN 44851; Moskvitin et al., GCN 44852; Sasaki et al., GCN 44857 ; Pankov et al., GCN 44858 ; Pankov et al., GCN 44862 ; Burkhonov et al., GCN 44865 ) in the stacked image. The upper limit is measured as follows: g > 21.1 AB (3-sigma, mid-time 19.68 h after the trigger). The photometry was calibrated against Pan-STARRS1 DR1 catalog and no correction for Galactic dust extinction was applied. We thank the observation assistants Hong-Xu Xue and Bo-Wen Li at Jilin observatory for their excellent support. The Chinese Ground Follow-up Telescope (C-GFT) for the SVOM mission is located at Jilin Station, Changchun Observatory, National Astronomical Observatories, CAS. It features two instruments: (1) CATCH at the Cassegrain focus with a 21 arcsec x 21 arcsec FOV for simultaneous g/r/i-band imaging, and (2) LATIOS, a 4k x 4k CMOS camera at the prime focus with a 1.28 deg x 1.28 deg FOV that images in g, r, and i bands via filter switching. View this GCN Circular online at https://gcn.nasa.gov/circulars/44872. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43004] GRB 260607B: AstroSat CZTI detection
by GCN Circulars 08 Jun '26

08 Jun '26

TITLE: GCN CIRCULAR NUMBER: 44871 SUBJECT: GRB 260607B: AstroSat CZTI detection DATE: 26/06/08 13:00:00 GMT FROM: Anuraag Arya at IIT Bombay <aryaanuraag910(a)gmail.com> Harsha K. H. (IUCAA), S. Salunke (IUCAA), A. Arya (IITB), A. Goyal (IITB), G. Waratkar (Caltech/IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration: Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long GRB 260607B which was also detected by Fermi GBM (Fermi GBM Team, GCN Circ. 44859), Fermi LAT (Airasca et. al. , GCN Circ. 44860). The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve showed multiple peaks of emission with the strongest peak at 2026-06-07 13:19:41.91 UTC. The measured peak count rate associated with the burst is 508 (+45, -30) counts/s above the background in the combined data of all quadrants, with a total of 8523 (+313, -323) counts. The local mean background count rate was 280 (+2, -2) counts/s. Using cumulative rates, we measure a T90 of 45.8 (+0.2, -0.6) s. The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.The light curve showed multiple peaks of emission with the strongest peak at 2026-06-07 13:19:41.36 UTC. The measured peak count rate associated with the burst is 4613 (+124, -120) counts/s above the background in the combined data of all quadrants, with a total of 79352 (+766, -730) counts. The local mean background count rate was 1278 (+4, -5) counts/s. We measure a T90 of 45.8 (+0.1, -0.1) s from the cumulative Veto light curve. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project. CZTI data products like interactive and downloadable light curves for this GRB can be found at: https://astrosat.iucaa.in/cift/cift_products/ET20260607T131928/ET20260607T1… CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project. CZTI GRB detections are reported regularly on the payload site at: http://astrosat.iucaa.in/czti/?q=grb View this GCN Circular online at https://gcn.nasa.gov/circulars/44871. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43003] GRB 260608A: SVOM detection of a burst
by GCN Circulars 08 Jun '26

08 Jun '26

TITLE: GCN CIRCULAR NUMBER: 44870 SUBJECT: GRB 260608A: SVOM detection of a burst DATE: 26/06/08 12:08:17 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> M. Brunet, L. Bouchet (IRAP), C.-W. Wang (IHEP) D.-F. Kong (GXU) report on behalf of the SVOM mission team: At 2026-06-08T11:35:32 UTC (T0), SVOM/ECLAIRs triggered and located the gamma-ray burst GRB 260608A (SVOM burst-id sb26060803), which is also detected by Fermi/GBM (GCN 44868). The following trigger information was received on the ground with low latency by the SVOM VHF Alert Network. The burst was detected both by the Count-Rate Trigger (CRT) and the Image Trigger (IMT), which produced a sequence of 34 alerts. IMT provided the alert with the best signal-to-noise-ratio in the image (SNR) of 24.71 in the [8-120] keV energy band over a time window of 81.92 seconds starting at 2026-06-08T11:35:14. The localization of the best alert is R.A., Dec. 81.3711, -48.3879 degrees: R.A. (J2000) = 5h25m29.07s Dec. (J2000) = -48d23m16.62s with a 90% confidence level (C.L.) radius of 3.70 arcmin (including systematic error of 2 arcmin added in quadrature). TThe SVOM/ECLAIRs light curve showed a multiple peak structure with a T90 duration of about 46.839 (-2.959 +3.411) s. This burst was also detected by SVOM/GRM with a significance of 18.20. The SVOM/GRM light curve showed a multiple peak structure with a T90 duration of about 53.73 (-2.457 +2.459) s. The SVOM/GRM light curve can be found here: https://www.bursthub.cn//admin/static/svgrb260608A.png Due to Sun constraint, no X-ray observation could be performed by SVOM/MXT and no optical observation could be performed by SVOM/VT for the time being. 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. SVOM/ECLAIRs was developed jointly by CNES, CEA-IRFU, CNRS-IRAP, CNRS-APC. SVOM/GRM was developed by the Institute of High Energy Physics (IHEP) of CAS. SVOM/MXT was developed jointly by CNES, CEA-IRFU, CNRS-IJCLab, University of Leicester, MPE. The Burst Advocate (BA) on shift for this alert is Chenwei Wang: cwwang(a)ihep.ac.cn Please contact the BA by email if you require additional information. View this GCN Circular online at https://gcn.nasa.gov/circulars/44870. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43002] GRB 260608A: Fermi GBM Final Real-time Localization
by GCN Circulars 08 Jun '26

08 Jun '26

TITLE: GCN CIRCULAR NUMBER: 44869 SUBJECT: GRB 260608A: Fermi GBM Final Real-time Localization DATE: 26/06/08 11:47:57 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 11:35:31 UT on 8 Jun 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260608A (trigger 802611336.05914 / 260608483). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 78.4, Dec = -45.2 (J2000 degrees, equivalent to J2000 05h 13m, -45d 12'), with a statistical uncertainty of 3.2 degrees. The angle from the Fermi LAT boresight is 29.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260608483/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260608483/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260608483/… View this GCN Circular online at https://gcn.nasa.gov/circulars/44869. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 43001] GRB 260608A: Fermi GBM Final Real-time Localization
by GCN Circulars 08 Jun '26

08 Jun '26

TITLE: GCN CIRCULAR NUMBER: 44868 SUBJECT: GRB 260608A: Fermi GBM Final Real-time Localization DATE: 26/06/08 11:46:30 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 11:35:31 UT on 8 Jun 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260608A (trigger 802611336.05914 / 260608483). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 78.4, Dec = -45.2 (J2000 degrees, equivalent to J2000 05h 13m, -45d 12'), with a statistical uncertainty of 3.2 degrees. The angle from the Fermi LAT boresight is 29.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260608483/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260608483/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260608483/… View this GCN Circular online at https://gcn.nasa.gov/circulars/44868. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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