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[vsnet-grb-info 42307] EP260402a/GRB 260402A: Einstein Probe detection of an X-ray transient
by GCN Circulars 02 Apr '26

02 Apr '26

TITLE: GCN CIRCULAR NUMBER: 44186 SUBJECT: EP260402a/GRB 260402A: Einstein Probe detection of an X-ray transient DATE: 26/04/02 14:16:37 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> Y. Q. Zhao (USTC,PRIC), C. L. Guo, J. W. Hu, C. Jin (NAO, CAS) on behalf of the Einstein Probe (EP) team: We report on the detection of an X-ray transient by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission, designated EP260402a. The transient triggered EP-WXT (ID: 01709259488) at 2026-04-02T10:30:41 (UTC). The WXT position of the source is R.A. = 170.994 deg, DEC = 63.604 deg (J2000) with an uncertainty of 3 arcmin in radius (90% C.L. statistical and systematic). EP260402a is temporally and spatially consistent with GRB 260402A (GCN #44181). A follow-up observation with the Follow-up X-ray Telescope (FXT) was performed automatically triggered by SVOM GRB detection, began at 2026-04-02T12:55:33Z. Within the WXT error circle, an uncatalogued X-ray source was detected at R.A. = 170.9607 deg, DEC = 63.6128 deg (J2000) with an uncertainty of 20 arcsec in radius (90% C.L. statistical and systematic). Further information will be updated when the telemetry data is received. Launched on January 9, 2024, EP is a space X-ray observatory to monitor the soft X-ray sky with X-ray follow-up capability (Yuan et al. 2022, Handbook of X-ray and Gamma-ray Astrophysics). View this GCN Circular online at https://gcn.nasa.gov/circulars/44186. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 42306] GRB 260402A: Kilonova-Catcher optical upper limit
by GCN Circulars 02 Apr '26

02 Apr '26

TITLE: GCN CIRCULAR NUMBER: 44185 SUBJECT: GRB 260402A: Kilonova-Catcher optical upper limit DATE: 26/04/02 13:09:54 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> M. Freeberg (KNC), D. Turpin (CEA-Saclay/Irfu), C. Andrade(UMN), S. Antier (IJCLab), M. Coughlin (UMN), S. Karpov (FZU), P. Hello (IJCLAB), M. Pillas (IAP) on behalf of the GRANDMA/Kilonova-Catcher collaboration: We observed the field of GRB 260402A detected by SVOM/ECLAIRs (Tan et al., GCN 44181) with the GRANDMA citizen science project Kilonova-catcher (KNC). Our observations were performed with the TEC160FL telescope operated by M. Freeberg. Our observations started at TGRB+20.8 min and were taken with the sdssr filter. In our stacked frames, subtracted from the PanSTARRS DR2 template image, we do not detect any optical counterpart in the SVOM/ECLAIRs error radius. We report our follow-up results in the table below: +----------------+----------+---------+---------------+--------------+ | Tmid-TGRB (min)| Exp (s) | Filter | Magnitude | Instrument | +================+==========+=========+===============+==============+ | 29.97 | 5 x 180s | r (AB) | 19.5 (5 sigma)| TEC160FL | +----------------+----------+---------+---------------+--------------+ All the data have been reduced by a single data processing pipeline, STDPipe (Karpov et al., 2022). Images obtained with the Sloan filters were calibrated using the PanSTARRS DR1 catalog. We use the SkyPortal application (skyportal.io) to monitor our observational campaign (Coughlin et al. 2023). GRANDMA is a worldwide telescope network (grandma.ijclab.in2p3.fr) devoted to the observation of transients in the context of multi-messenger astrophysics (Antier et al. 2020 MNRAS 497, 5518). Kilonova-Catcher (KNC) is the citizen science program of GRANDMA (http://kilonovacatcher.in2p3.fr/) View this GCN Circular online at https://gcn.nasa.gov/circulars/44185. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 42305] GRB 260402A: MASTER optical observations
by GCN Circulars 02 Apr '26

02 Apr '26

TITLE: GCN CIRCULAR NUMBER: 44184 SUBJECT: GRB 260402A: MASTER optical observations DATE: 26/04/02 12:22:04 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov(a)xray.sai.msu.ru> L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez,J.Martinez, A.R.Corella, J.Tanori, L. Villalobos, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory) V.Lipunov, A.Kuznetsov, I.Panchenko, P.Balanutsa, G.Antipov, E.Gorbovskoy, N.Tiurina, V.Senik, A.Chasovnikov, Ya.Kechin, V.Topolev, D.Vlasenko, A.Sankovich,Yu.Tselik (Lomonosov MSU), M.J. Segura, C.Francile, F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), N.Budnev, O.Gress (ISU), A.Sosnovskij (CrAO), D.Buckley (SAAO), R.Rebolo (The Instituto de Astrofisica de Canarias), A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity) MASTER-OAGH robotic telescope of MASTER Global Robotic Net [1-4] started SVOM GRB 260302A (Tan et al. GCN 44181, Gotz et al. GCN 44182 Ttrigger=2026-04-02 10:30:17UT) at 2026-04-02 10:55:46UT (25min after trigger time) with m_lim=19.1m(unfiltered) at 1st image. We didn't find new object inside error-box at single images.Observations and reduction will be continued. Error-box altitude was 34deg, the sun_alt=-28deg, the FULL moon (0.99) alt=27deg (in 75 deg from erro-box) Cover map is available here https://master.sai.msu.ru/site/master2/event.php?id=3227188 [1] Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L [2] Lipunov et al. 2022, Universe, Vol. 8(5), id.271 [3] Lipunov et a. 2019, ARep, vol.63, 293 [4] Lipunov et al. 2023, Astronomical Robotic Networks and Operative Multichanel Astrophysics,Lomonosov MSU PRESS, 591pp. http://www.pereplet.ru/lipunov/625.html#625 View this GCN Circular online at https://gcn.nasa.gov/circulars/44184. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 42304] GRB 260402A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
by GCN Circulars 02 Apr '26

02 Apr '26

TITLE: GCN CIRCULAR NUMBER: 44183 SUBJECT: GRB 260402A: SVOM/COLIBRÍ (FM-GFT) optical upper limit DATE: 26/04/02 12:17:52 GMT FROM: antier(a)ijclab.in2p3.fr Sarah Antier (IJCLAB), Rosa L. Becerra (UNAM), 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), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Jean-Grégoire Ducoin (CPPM), Francis Fortin (IRAP), Leonardo García García (UNAM), Ramandeep Gill (UNAM), Noémie Globus (UNAM), Marion Guelfand (CPPM), Asuka Kuwata (UNAM), Massimiliano Lincetto (CPPM), 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), Antonio de Ugarte Postigo (LAM), W. Tan (IHEP), R. Li (IHEP) report: We imaged the field of the SVOM GRB 260402A (Tan et al., GCN Circ. 44181) using the DDRAGO wide-field imager on the SVOM/COLIBRÍ (FM-GFT) telescope. We observed from 2026-04-02 10:37:04 to 11:52:05 UTC (from 7 minutes after the trigger) and obtained about 45 min of exposure in the r/z filters. The data were reduced and coadded with the ASU and Colibri 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 the stacked image, we do not detect any new source at the ECLAIRs and MXT source position (Tan et al., GCN Circ. 44181, Gotz et al., GCN Circ.44182) and down to the following 3-sigma limit: r > 22.6 z > 22.0 Further observations 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/44183. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 42303] GRB 260402A: SVOM/MXT candidate X-ray afterglow
by GCN Circulars 02 Apr '26

02 Apr '26

TITLE: GCN CIRCULAR NUMBER: 44182 SUBJECT: GRB 260402A: SVOM/MXT candidate X-ray afterglow DATE: 26/04/02 11:12:18 GMT FROM: Diego Gotz at CEA <diego.gotz(a)cea.fr> D. Gotz (CEA Saclay) on behalf of the SVOM MXT team reports: MXT observed the field of GRB 260402A at 10:53:24 U.T., about 23 minutes after the ECLAIRs trigger. The automatic on board software detects a faint source at R.A.= 170.806 deg (J2000) Dec.= +63.627 deg (J2000) with a R90 uncertainty (incdluding systematics) of 114 arc sec. This position is at 4.7 arc min from the ECLAIRs position reported by Tan et al. (GCN 44181). Further data will be needed to confirm the afterglow nature of this candidate source. 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 Wenjun Tan: tanwj at 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/44182. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 42302] GRB 260402A: SVOM detection of a burst
by GCN Circulars 02 Apr '26

02 Apr '26

TITLE: GCN CIRCULAR NUMBER: 44181 SUBJECT: GRB 260402A: SVOM detection of a burst DATE: 26/04/02 10:51:18 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> W. Tan, R. Li (IHEP), M. Brunet, O. Godet (IRAP), D. Gotz (CEA), report on behalf of the SVOM mission team: At 2026-04-02T10:30:17 UTC (T0), SVOM/ECLAIRs triggered and located the gamma-ray burst GRB 260402A (SVOM burst-id sb26040203). 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 17 alerts. CRT provided the alert with the best signal-to-noise-ratio in the image (SNR) of 18.74 in the [5-20] keV energy band over a time window of 10.20 seconds starting at 2026-04-02T10:30:17. The localization of the best alert is R.A., Dec. 170.982, 63.622 degrees: R.A. (J2000) = 11h23m55s Dec. (J2000) = 63d37m18s with a 90% confidence level (C.L.) radius of 4.57 arcmin (including systematic error of 2 arcmin added in quadrature). The SVOM/ECLAIRs light curve showed a broad peak structure with a T90 duration of 15.17 (-1.27 / +5.86) s in the 5-120 keV energy band. This burst was also detected by SVOM/GRM with a significance of 7.20. SVOM slewed to the burst. No prompt X-ray observation could be performed by SVOM/MXT for the time being. 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 Wenjun Tan: tanwj at 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/44181. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 42301] Fermi GRB 260401A: Global MASTER-Net observations report
by GCN Circulars 02 Apr '26

02 Apr '26

TITLE: GCN CIRCULAR NUMBER: 44180 SUBJECT: Fermi GRB 260401A: Global MASTER-Net observations report DATE: 26/04/02 06:00:50 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-OAFA robotic telescope [1] located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 260401A ( Fermi GBM team, GCN 44174) errorbox 63483 sec after notice time and 63518 sec after trigger time at 2026-04-02 04:32:04 UT, with upper limit up to 19.0 mag. The observations began at zenith distance = 29 deg. The sun altitude is -63.7 deg. The galactic latitude b = 38 deg., longitude l = 337 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3225119 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 33732 | 2026-04-01 20:15:08 | MASTER- | (14h 42m 26.86s , -15d 41m 21.2s) | C | 60 | 12.9 | 63549 | 2026-04-02 04:32:04 | MASTER-OAFA | (14h 25m 14.66s , -15d 38m 17.7s) | C | 60 | 18.4 | 63609 | 2026-04-02 04:32:04 | MASTER-OAFA | (14h 25m 14.66s , -15d 38m 17.8s) | C | 180 | 19.0 | Coadd 63624 | 2026-04-02 04:33:19 | MASTER-OAFA | (14h 25m 11.96s , -15d 36m 34.5s) | C | 60 | 18.3 | 63700 | 2026-04-02 04:34:36 | MASTER-OAFA | (14h 25m 12.06s , -15d 37m 47.2s) | 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/44180. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 42300] GRB 260401A: Fermi GBM Observation
by GCN Circulars 01 Apr '26

01 Apr '26

TITLE: GCN CIRCULAR NUMBER: 44179 SUBJECT: GRB 260401A: Fermi GBM Observation DATE: 26/04/01 23:33:42 GMT FROM: Daniel Fernandez at University of Alabama In Huntsville (UAH) <df0062(a)uah.edu> D. Fernandez (UAH), M. Dafčíková (MUNI) and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team: "At 10:53:26.00 UT on 01 April 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260401A (trigger 796733611/260401454), which was also detected by MAXI (T. Usuki et al. 2026, GCN 44176). The Fermi GBM on-ground location (GCN 44174) is consistent with the MAXI position. The angle from the Fermi LAT boresight is 60 degrees. The GBM light curve consists of a bright emission episode with multiple peaks with a duration (T90) of about 27 s (50-300 keV). The time-averaged spectrum from T0-0.8 to T0+32.1 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.78 +/- 0.01 and the cutoff energy, parameterized as Epeak, is 239 +/- 1 keV. The event fluence (10-1000 keV) in this time interval is (1.80 +/- 0.02)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+7.5 s in the 10-1000 keV band is 21.1 +/- 0.4 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/" View this GCN Circular online at https://gcn.nasa.gov/circulars/44179. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 42299] GRB 260401A: NuSTAR detection of prompt emission
by GCN Circulars 01 Apr '26

01 Apr '26

TITLE: GCN CIRCULAR NUMBER: 44178 SUBJECT: GRB 260401A: NuSTAR detection of prompt emission DATE: 26/04/01 23:21:40 GMT FROM: Gaurav Waratkar at Caltech <gauravwaratkar(a)iitb.ac.in> G. Waratkar (Caltech) and B. Grefenstette (Caltech) report on behalf of the NuSTAR Search for INteresting Gamma-ray Signals (SINGS) working group: The NuSTAR SINGS working group reports the detection of prompt emission from the long-duration GRB 260401A in both the NuSTAR CsI anti-coincidence shields. Details of the search algorithm will be described in a future paper. The NuSTAR SINGS algorithm, triggered at 2026-04-01 10:53:26.0 UTC, shows a detection of GRB 260401A, consistent with Fermi/GBM (Fermi GBM team, GCN Circ. 44174, MAXI/GSC (Usuki et al., GCN Circ. 44176), CALET/GBM (Cannady et al., GCN Circ. 44177) and SVOM/GRM (GCN Notices). The NuSTAR CsI shield data are recorded at 1 Hz. We detect a single peak lasting for ~10-s which is consistent with the bright part of the burst as seen in the GBM lightcurve. The peak count rate is ~3000-cps with a baseline rate of ~1000-cps during this time period. We do not see any evidence in the signal above 100 keV in the CZT detectors. The GBM localization (GCN Circular 44174) at RA = 219.5, Dec = -17.4 implies an offset from the NuSTAR boresight of 42-deg (i.e. from the side of the instrument) and an offset from the geocenter of 73-deg. Lightcurves and analysis for this GRB can be found here: https://nustarsoc.caltech.edu/NuSTAR_Public/grbs/reports/2026/260401A/ Information on NuSTAR SINGS can be found here: https://nustarsoc.caltech.edu/NuSTAR_Public/grbs/ NuSTAR is a NASA Small Explorer mission led by Caltech and managed by JPL for NASA's Science Mission Directorate in Washington. View this GCN Circular online at https://gcn.nasa.gov/circulars/44178. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 42298] GRB 260401A: CALET Gamma-Ray Burst Monitor detection
by GCN Circulars 01 Apr '26

01 Apr '26

TITLE: GCN CIRCULAR NUMBER: 44177 SUBJECT: GRB 260401A: CALET Gamma-Ray Burst Monitor detection DATE: 26/04/01 16:20:41 GMT FROM: Yuta Kawakubo at Aoyama Gakuin University <kawakubo(a)phys.aoyama.ac.jp> N. Cannady (GSFC), A. Yoshida, T. Sakamoto, S. Sugita, Y. Kawakubo (AGU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA), Y. Asaoka (ICRR), S. Torii, Y. Akaike, K. Kobayashi (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), M. L. Cherry (LSU), S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena), and the CALET collaboration: The long GRB 260401A (Fermi GBM Final Real-time Localization: Fermi GBM team, GCN Circ. 44174; BALROG localization: Preis et al., GCN Circ 44175; MAXI/GSC detection: Usuki et al., GCN Circ 44176) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 10:53:31.52 UTC on 1 April 2026 (https://cgbm.calet.jp/cgbm_trigger/flight/1459075956/index.html) The burst signal was seen by all CGBM detectors. The burst light curve shows a single pulse that starts at T+1.4 sec, peaks at T+2.2 sec, and ends at T+6.3 sec. The T90 and T50 durations measured by the SGM data are 4.4 +/- 0.6 sec and 2.0 +/- 0.3 sec (40-1000 keV), respectively. The ground-processed light curve is available at https://cgbm.calet.jp/cgbm_trigger/ground/1459075956 The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at Waseda University. View this GCN Circular online at https://gcn.nasa.gov/circulars/44177. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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