October 2025 - vsnet-grb-info - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-grb-info 40534] GRB 251026A: SVOM detection of a long burst
by GCN Circulars 26 Oct '25

26 Oct '25

TITLE: GCN CIRCULAR NUMBER: 42454 SUBJECT: GRB 251026A: SVOM detection of a long burst DATE: 25/10/26 09:04:48 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> J.X Cao (GXU), X. Tian (GXU), J-L. Atteia (IRAP), W.J Xie (NAOC), F. Lacreu (IAP), M. Moita (CEA), report on behalf of the SVOM mission team: At 2025-10-26T08:27:22 UTC (T0), SVOM/ECLAIRs triggered and located the gamma-ray burst GRB 251026A (SVOM burst-id sb25102605). 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 11 alerts. IMT provided the alert with the best signal-to-noise-ratio in the image (SNR) of 11.73 in the [8-120] keV energy band over a time window of 81.92 seconds starting at 2025-10-26T08:26:46. The localization of the best alert is R.A., Dec. 72.5819, 51.8058 degrees (J2000) with a 90% confidence level (C.L.) radius of 6.86 arcmin (including systematic error of 2 arcmin added in quadrature). SVOM slewed to the burst. SVOM/MXT began observing the field at 2025-10-26T08:31:19 UTC, 237 seconds after T0. Using onboard processed data we found an uncatalogued X-ray source located at R.A., Dec. 72.707, 51.776 degrees: R.A. (J2000) = 04h50m49s Dec. (J2000) = 51d46m32s with a 90% C.L. radius of 65 arcseconds. This location is 5.17 arcminutes from the ECLAIRs onboard position. This position may be improved as more data is received. VT began observing the field after the slew. The analysis of the data will be published in a future circular. 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 Jiaxin Cao: cjx(a)st.gxu.edu.cn. Please contact the BA by email if you require additional information. View this GCN Circular online at https://gcn.nasa.gov/circulars/42454. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40533] GRB 251025B: SVOM/VT optical bump
by GCN Circulars 26 Oct '25

26 Oct '25

TITLE: GCN CIRCULAR NUMBER: 42453 SUBJECT: GRB 251025B: SVOM/VT optical bump DATE: 25/10/26 04:30:16 GMT FROM: Huali Li at at NAOC, SVOM <lhl(a)nao.cas.cn> H.L. Li, L.P. Xin, Y.L. Qiu, C. Wu, Y.N. Ma, Z.H. Yao, X.H. Han, J. Wang, H.B. Cai, W.J. Xie, Y. Xu, J.R. Xu, P.P. Zhang, Y.J. Xiao, J.S. Deng, J.Y. Wei (NAOC), J. Palmerio (CEA), J.X. Cao, X. Tian (GXU), S. Hussein (IJCLab), M. Brunet (IRAP) report on behalf of the SVOM team. SVOM performed an automatic slew on the burst GRB 251025B triggered by SVOM/ECLAIRs (Julakanti et al., GCN 42437) in VT_B (400nm-650nm) and VT_R (650nm-1000nm) channels simultaneously. The observation began at 2025-10-25T14:26:52, i.e., 167 sec post trigger. The optical counterpart (Wu et al., GCN 42438, 42440; Budnev et al., GCN 42439; Mohan et al., GCN 42447; Fung et al., GCN 42450) consistent with the location of Swfit-XRT (Beardmore et al., GCN 42445) was clearly detected in both VT channels. The brightness was decaying with a slope of -0.7 before 3000 sec post trigger, followed by a bump with the peak of VT_R~19.59+/-0.05 mag and VT_B~19.95+/-0.05 mag at the mid time of 5.24 hours post trigger. Our photometry was estimated in AB magnitude, and not corrected for Galactic extinction. More follow-up for this burst is encouraged. The Space Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA, China), National Center for Space Studies (CNES, France) and the Chinese Academy of Sciences (CAS, China), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. VT was jointly developed by Xi'an Institute of Optics and Precision Mechanics (XIOPM), CAS and National astronomical observatories (NAOC), CAS. View this GCN Circular online at https://gcn.nasa.gov/circulars/42453. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40532] GRB 251025B: SVOM/COLIBRÍ (FM-GFT) strong rebrightening of the optical counterpart
by GCN Circulars 26 Oct '25

26 Oct '25

TITLE: GCN CIRCULAR NUMBER: 42452 SUBJECT: GRB 251025B: SVOM/COLIBRÍ (FM-GFT) strong rebrightening of the optical counterpart DATE: 25/10/26 04:18:33 GMT FROM: Margarita Pereyra Talamantes at IA-UNAM Ensenada <mpereyra(a)astro.unam.mx> Margarita Pereyra (UNAM), Antonio de Ugarte Postigo (LAM), Benjamin Schneider (LAM), Alan M. Watson (UNAM), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Jean-Luc Atteia (IRAP), Dalya Akl (NYUAD), Camila Angulo (UNAM), Sarah Antier (IJCLAB), Rosa L. Becerra (UNAM), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Jean-Grégoire Ducoin (CPPM), Francis Fortin (IRAP), Leonardo García-García (UNAM), Ramandeep Gill (UNAM), Noémie Globus (UNAM), Diego López-Cámara (UNAM), Kin Ocelotl López (UNAM), Francesco Magnani (CPPM), Enrique Moreno Méndez (UNAM), Ny Avo Rakotondrainibe (LAM), Fredd Sánchez Álvarez (UNAM), and S. Hussein (IJCLab) report: We imaged the field of the SVOM GRB 251025B (Hussein et al., GCN Circ. 42437) using the DDRAGO two-channel wide-field imager on the SVOM/COLIBRÍ (FM-GFT) telescope. We observed from 2025-10-26 02:54 to 03:17 (12.51 to 12.89 hours after the trigger) and obtained 6, 5, 5, and 16 minutes exposure in the the g, r, i, and z filters. The images were analyzed with STDWeb/STDPipe (Karpov 2025). The photometry was calibrated using nearby stars from the PanSTARRS catalog, is in the AB system, and is not corrected for Galactic extinction. We detect the optical counterpart (Wu et al., GCN Circ. 42438; Gress et al., GCN Circ. 42439; Wu et al., GCN Circ. 42440; Beardmore et al., GCN Circ. 42445; Mohan et al., GCN Circ. 42447; Hernández Funget al., GCN Circ. 42450) with preliminary magnitudes of: g = 20.58 +/- 0.03 r = 20.20 +/- 0.03 i = 19.90 +/- 0.04 z = 19.79 +/- 0.04 We note that the afterglow appears to be brighter in r in our observations at about 12 hours than it was in the observations of Mohan et al. (GCN Circ. 42447) at about 2 hours, suggesting a very strong rebrightening. We further note a possible host galaxy candidate at the afterglow position in the Legacy Survey with r ≈ 23.3 and a photometric redshift if z ≈ 0.98 +/- 0.19. This is consistent with the detection in g. Further observations and analysis are ongoing. We thank the staff of the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir and the COLIBRÍ and DDRAGO engineering teams. 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/42452. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40531] GRB 251023A: SVOM/GRM observation
by GCN Circulars 26 Oct '25

26 Oct '25

TITLE: GCN CIRCULAR NUMBER: 42451 SUBJECT: GRB 251023A: SVOM/GRM observation DATE: 25/10/26 03:54:05 GMT FROM: Chenwei Wang at IHEP <cwwang(a)ihep.ac.cn> SVOM/GRM team: Chen-Wei Wang, Zheng-Hang Yu, Wen-Jun Tan, Yue Huang, Shi-Jie Zheng, Shao-Lin Xiong, Shuang-Nan Zhang (IHEP) SVOM/ECLAIRs team: Feliu Lacreu (IAP) Report on behalf of the SVOM team: SVOM/GRM was triggered in-flight by a burst GRB 251023A (SVOM trigger reference: sb25102301) at 2025-10-23T05:57:44.000 UTC (T0), which is also detected by Fermi/GBM (Fermi GBM team, GCN#42385) and Glowbug (R. Woolf, GCN#42408). With the event-by-event data downloaded through the X-band ground station, the GRM light curve shows that this burst consists of multiple peaks with a T90 of 63.5 +19.5/-5.5 s in the 15-5000 keV band. The SVOM/GRM light curve can be found here: https://www.bursthub.cn//admin/static/svgrb251023A.png In addition, the position of this burst, as determined by Fermi/GBM (RA= 39.87, DEC= -6.53, GCN#42385), is located at about 51 degrees from the SVOM optical axis, which is outside the ECLAIRs field of view. With this localization, the time-averaged spectrum from T0-2 to T0+70 s is best fitted by a power law function with an exponential high-energy cutoff. The power law index is -0.45 +0.25/-0.26 and the cutoff energy, parameterized as Epeak, is 143 +26/-19 keV. The event fluence (10-1000 keV) in this time interval is (5.47 +0.55/-0.56)E-6 erg/cm^2. The localization of GRB 251023A in the 'Amati' relation diagram is shown at: https://www.bursthub.cn//admin/static/svgrb251023A_amati.png The Space Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA, China), National Center for Space Studies (CNES, France) and the Chinese Academy of Sciences (CAS, China), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. GRM is developed by the Institute of High Energy Physics (IHEP) of CAS. The SVOM point of contact for this burst is: Chen-Wei Wang (IHEP)(cwwang(a)ihep.ac.cn) View this GCN Circular online at https://gcn.nasa.gov/circulars/42451. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40530] GRB 251025B: ULL-ASTRO-MASTER optical counterpart detection with IAC80 telescope at Teide Observatory
by GCN Circulars 26 Oct '25

26 Oct '25

TITLE: GCN CIRCULAR NUMBER: 42450 SUBJECT: GRB 251025B: ULL-ASTRO-MASTER optical counterpart detection with IAC80 telescope at Teide Observatory DATE: 25/10/26 03:31:47 GMT FROM: Ismael Perez-Fournon at Instituto de Astrofisica de Canarias <ipf(a)iac.es> J. Hernández Fung, P.G. Berdayes, M. Contreras, B. Gandolfi, L. Juliá-Maroto, A. Schenone-Zanuzzi, E. Urquijo-Rodríguez, J. Basurto Merino, A. Caballero-Almagro, A. Cerón, F. Díaz-Segado, T. Ferrer-Laviña, V. Ghiraldo, E. Lekaroz-Urriza, M. Manzano García, E. Mejía-Martínez, J. Prieto Polo, M. Pulido-Torres, M. Quintana-Ansaldo, A. Selezneva, T. Tundidor Rodríguez (all ULL), M. Abdul-Masih (IAC and ULL), and I. Pérez-Fournon (IAC and ULL). Following the detection of GRB 251025B (sb25102502) by SVOM (Hussein et al., GCN circ. 42437), we observed the field with the IAC80 telescope equipped with the CAMELOT2 camera at Teide Observatory (Tenerife, Canary Islands, Spain). The observation, a single exposure of 300 sec in the SDSS g' filter, started on 2025-10-26 at 00:50:31 UT, about 10.44 hours after the SVOM trigger. The optical counterpart detected by Wu et al. (GCN circ. 42438), Gress et al. (GCN circ. 42439), Wu et al. (GCN circ. 42440), and Mohan et al. (GCN circ. 42447) is clearly detected in our image with a magnitude of g = 20.37 +/- 0.12 (AB), calibrated against PanSTARRS-1 DR2 stars and not corrected for galactic extinction. The optical counterpart position is consistent within the errors with the position of the X-ray afterglow measured by Swift-XRT (Beardmore et al. GCN circ. 42445). This work is based on observations made with the IAC80 telescope operated on the island of Tenerife by the Instituto de Astrofísica de Canarias in the Spanish Observatorio del Teide. We acknowledge the expert assistance of Roberto C. Álvarez and Borja Castañeda. These observations are part of a course in Astrophysical Techniques of the Master in Astrophysics of the Astrophysics Department of the University of La Laguna in collaboration with the Instituto de Astrofísica de Canarias (La Laguna, Tenerife, Canary Islands, Spain). This work made use of the Astro-COLIBRI platform (P. Reichherzer et al. 2021, ApJS, 256, 5). View this GCN Circular online at https://gcn.nasa.gov/circulars/42450. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40529] GRB 251025C: Fermi GBM Final Real-time Localization
by GCN Circulars 25 Oct '25

25 Oct '25

TITLE: GCN CIRCULAR NUMBER: 42449 SUBJECT: GRB 251025C: Fermi GBM Final Real-time Localization DATE: 25/10/25 23:19:13 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 23:08:40 UT on 25 Oct 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 251025C (trigger 783126525.293544 / 251025964). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 170.7, Dec = 54.9 (J2000 degrees, equivalent to J2000 11h 22m, 54d 53'), with a statistical uncertainty of 2.2 degrees. The angle from the Fermi LAT boresight is 103.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251025964/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251025964/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251025964/… View this GCN Circular online at https://gcn.nasa.gov/circulars/42449. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40528] Konus-Wind detection of GRB 251016B
by GCN Circulars 25 Oct '25

25 Oct '25

TITLE: GCN CIRCULAR NUMBER: 42448 SUBJECT: Konus-Wind detection of GRB 251016B DATE: 25/10/25 20:36:05 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 251016B (Ferm-GBM detection: The Fermi GBM team, GCN 42316; Godwin and Meegan, GCN 42383; CALET-GBM detection: Yamaoka et al., GCN 42320; AstroSat-CZTI detection: Harsha et al., GCN 42324; IPN triangulation: Kozyrev et al., GCN 42403) triggered Konus-Wind at T0=86340.495 s UT (23:59:00.495). The burst light curve shows a single pulse which starts at ~T0-0.5 s and has a total duration of ~18.5 s. The emission is seen up to ~6 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB251016_T86340/ As observed by Konus-Wind, the burst had a fluence of 3.50(-0.18,+0.18)x10^-5 erg/cm2, and a 64-ms peak flux, measured from T0+2.320 s, of 1.22(-0.11,+0.11)x10^-5 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum of the burst (measured from T0 to T0+11.520 s) is best fit in the 20 keV - 10 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -0.98(-0.06,+0.06), the high energy photon index beta = -2.29(-0.10,+0.08), the peak energy Ep = 226(-18,+19) keV (chi2 = 93/85 dof). The spectrum near the maximum count rate (measured from T0+0.256 to T0+3.328 s) is best fit in the 20 keV - 10 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -0.85(-0.05,+0.06), the high energy photon index beta = -2.41(-0.11,+0.09), the peak energy Ep = 294(-21,+21) keV (chi2 = 67/67 dof). 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/42448. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40527] GRB 251025B: GROWTH-India Telescope optical observations
by GCN Circulars 25 Oct '25

25 Oct '25

TITLE: GCN CIRCULAR NUMBER: 42447 SUBJECT: GRB 251025B: GROWTH-India Telescope optical observations DATE: 25/10/25 20:34:06 GMT FROM: V. Swain at IIT Bombay <vishwajeet.s(a)iitb.ac.in> T. Mohan, V. Swain, S. Patil, A.P. Saikia, V. Bhalerao (IITB), G.C. Anupama, S. Barway (IIA) and K. Angail (IAO) report on behalf of the GIT team: We observed the field of SVOM GRB 251025B (Hussein et al., GCN 42437), with 0.7m GROWTH-India Telescope (GIT). We started the observation at 2025-10-25 15:47:08 UT, i.e., 1.38 hours after the SVOM trigger. Multiple exposures were obtained in the r′-filter, and we detect the optical counterpart in our stacked image. The photometry result follows as: | MJD (mid) | tmid - t0 (hours) | Filter | Exposure (s) | Magnitude (AB) | | --------- | ----------------- | ------ | ------------ | -------------- | |60973.68833| 2.12 | r' | 4 x 360 | 20.41 +- 0.11 | The measurement is calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction. Our result is consistent with other optical observations (WU et al., GCN 42438; Gress et al., GCN 42439; Wu et al., GCN 42440). Further multiband optical observations are ongoing. The GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/. View this GCN Circular online at https://gcn.nasa.gov/circulars/42447. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40526] GRB 251025B: GROWTH-India Telescope optical observations
by GCN Circulars 25 Oct '25

25 Oct '25

TITLE: GCN CIRCULAR NUMBER: 42447 SUBJECT: GRB 251025B: GROWTH-India Telescope optical observations DATE: 25/10/25 20:34:06 GMT FROM: V. Swain at IIT Bombay <vishwajeet.s(a)iitb.ac.in> T. Mohan, V. Swain, S. Patil, A.P. Saikia, V. Bhalerao (IITB), G.C. Anupama, S. Barway (IIA) and K. Angail (IAO) report on behalf of the GIT team: We observed the field of SVOM GRB 251025B (Hussein et al., GCN 42437), with 0.7m GROWTH-India Telescope (GIT). We started the observation at 2025-10-25 15:47:08 UT, i.e., 1.38 hours after the SVOM trigger. Multiple exposures were obtained in the r′-filter, and we detect the optical counterpart in our stacked image. The photometry result follows as: | MJD (mid) | tmid - t0 (hours) | Filter | Exposure (s) | Magnitude (AB) | | --------- | ----------------- | ------ | ------------ | -------------- | |60973.68833| 2.12 | r' | 4 x 360 | 20.41 +- 0.11 | The measurement is calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction. Our result is consistent with other optical observations (WU et al., GCN 42438; Gress et al., GCN 42439; Wu et al., GCN 42440). Further multiband optical observations are ongoing. The GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/. View this GCN Circular online at https://gcn.nasa.gov/circulars/42447. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40525] GRB 251024A: Swift/UVOT Upper Limits
by GCN Circulars 25 Oct '25

25 Oct '25

TITLE: GCN CIRCULAR NUMBER: 42446 SUBJECT: GRB 251024A: Swift/UVOT Upper Limits DATE: 25/10/25 20:11:36 GMT FROM: Mike Siegel at PSU/Swift MOC <mhs18(a)psu.edu> M. H. Siegel and M. J. Moss (GSFC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 251024A 132 s after the BAT trigger (Moss et al., GCN Circ. 42426). No optical afterglow consistent with the XRT position (Beardmore et al., GCN Circ. 42430) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 132 282 147 >21.0 u_FC 290 540 246 >19.9 white 132 591 167 >21.0 v 622 641 19 >18.0 b 547 567 20 >19.8 u 290 540 246 >19.9 w2 597 617 20 >19.2 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.044 in the direction of the burst (Schlegel et al. 1998). View this GCN Circular online at https://gcn.nasa.gov/circulars/42446. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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