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

[vsnet-grb-info 39160] GRB 250717A: Fermi GBM Final Real-time Localization
by GCN Circulars 17 Jul '25

17 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41105 SUBJECT: GRB 250717A: Fermi GBM Final Real-time Localization DATE: 25/07/17 03:58:51 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 03:48:11 UT on 17 Jul 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250717A (trigger 774416896.059134 / 250717158). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 22.9, Dec = 3.5 (J2000 degrees, equivalent to J2000 01h 31m, 3d 30'), with a statistical uncertainty of 2.9 degrees. The angle from the Fermi LAT boresight is 60.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250717158/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250717158/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250717158/… View this GCN Circular online at https://gcn.nasa.gov/circulars/41105. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39159] GRB 250716A: Swift ToO observations
by GCN Circulars 16 Jul '25

16 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41104 SUBJECT: GRB 250716A: Swift ToO observations DATE: 25/07/16 23:30:19 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 250716A. Automated analysis of the XRT data will be presented online at https://www.swift.ac.uk/ToO_GRBs/00021845 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/41104. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39158] GRB 250716A: GOTO tentative optical counterpart candidate
by GCN Circulars 16 Jul '25

16 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41103 SUBJECT: GRB 250716A: GOTO tentative optical counterpart candidate DATE: 25/07/16 20:30:19 GMT FROM: Ben Rayson at University of Leicester <br155(a)leicester.ac.uk> B. Rayson, D. O’Neill, B. P. Gompertz, A. Kumar, R. Starling, K. Ackley, M. J. Dyer, J. Lyman, K. Ulaczyk, B. Godson, D. Steeghs, D. K. Galloway, V. Dhillon, P. O'Brien, G. Ramsay, K. Noysena, R. Kotak, R. P. Breton, L. K. Nuttall, and J. Casares report on behalf of the 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 GRB 250716A (Fermi GBM Team, GCNs 41099, 41102). Targeted observations were performed beginning at 2025-07-16 17:07:29 UT, (+15.64h post trigger) and continued through to 2025-07-16 19:03:17 UT (+17.57h post trigger). 85 images were taken, across 10 unique pointings, covering 203 sq degrees, within the 90% localisation contour. ~90.0% of the total 2D localisation probability was covered, with an average 5-sigma depth of 19.9 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. A new optical source GOTO25eyp (AT 2025rhc) is identified within the GBM 90% localisation region, lying on the 16% probability contour. The source was initially detected with magnitude L = 18.20 ± 0.04 AB mag at +16.33h post trigger, before fading to L = 18.26 ± 0.04 AB mag at +17.46h post trigger. In total the source was detected in three consecutive epochs. The measured magnitudes are consistent with a decay rate of ~t^(-0.83±0.09). However, we caution that the measured decay is based on a relatively short temporal baseline and is therefore sensitive to scatter in the photometric measurements. The source is coincident with a faint (g=25.15 AB mag) extended source in the legacy survey with a mean photo z=0.98 ± 0.21. We find no evidence of the source prior to the GRB trigger time in previous GOTO observations or the ATLAS forced photometry server (Shingles et al. 2021). Due to the absence of pre-trigger detections, possible power-law decay, and the presence of a candidate host galaxy, we propose GOTO25eyp / AT 2025rhc as a candidate optical counterpart for GRB 250716A. Follow-up observations are encouraged. Magnitudes were calibrated using ATLAS-REFCAT2 (Tonry et al. 2018) and are 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 and the Instituto de Astrofisica de Canarias (IAC). View this GCN Circular online at https://gcn.nasa.gov/circulars/41103. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39157] GRB 250716A: Fermi GBM Observation
by GCN Circulars 16 Jul '25

16 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41102 SUBJECT: GRB 250716A: Fermi GBM Observation DATE: 25/07/16 15:35:42 GMT FROM: oindabimukherjee(a)gmail.com O. Mukherjee (USRA) and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team: "At 01:29:06.25 UT on 16 July 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250716A (trigger 774322151/250716062). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 65.72, Dec = -48.56 (J2000 degrees, equivalent to J2000 4h 22m, -48d 33'), with a statistical uncertainty of 1.00 degrees. (radius, 1-sigma containment, statistical only; there is additionally a systematic error which we have characterized as a mixture of two Gaussians, one with a radius of 1.8 degrees (52% contribution) and one with a radius of 4.1 degrees (47% contribution) [A. Goldstein et al. 2020, ApJ, 895, 1]). The angle from the Fermi LAT boresight is 126 degrees. The GBM light curve consists of two pulses with a duration (T90) of about 66 s (50-300 keV). The time-averaged spectrum from T0-3.1 to T0+79.9 s is best fit by a Band function with Epeak = 1153 +/- 133 keV, alpha = -1.29 +/- 0.01, and beta = -1.89 +/- 0.03. The event fluence (10-1000 keV) in this time interval is (9.9 +/- 0.1)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+5.5 s in the 10-1000 keV band is 37.9 +/- 0.7 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/41102. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39156] GRB 250714A: SVOM/GRM observation
by GCN Circulars 16 Jul '25

16 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41101 SUBJECT: GRB 250714A: SVOM/GRM observation DATE: 25/07/16 15:02:55 GMT FROM: tanwj(a)ihep.ac.cn SVOM/GRM team: Wen-Jun Tan, Chen-Wei Wang, Shi-Jie Zheng, Yue Huang, Shao-Lin Xiong, Shuang-Nan Zhang (IHEP) SVOM/ECLAIRs team: Jean-Luc Atteia, Olivier Godet (IRAP) Report on behalf of the SVOM team: SVOM/GRM was triggered in-flight by a bright burst GRB 250714A (SVOM trigger reference: sb25071402) at 2025-07-14T07:15:27.00 UTC (T0), which is also detected by Fermi/GBM (Fermi GBM Team, GCN#41088). With the event-by-event data downloaded through the X-band ground station, the GRM light curve shows that this burst consists of a main peak following behind a relatively weak emission, with a T90 of 21.6+/-10.2 s in the 15-500 keV band. The SVOM/GRM light curve can be found here: https://www.bursthub.cn//admin/static/svgrb250714A.png In addition, the position of this burst, as determined by Fermi/GBM (RA= 94.7, DEC= -21.2, GCN#41088), is located at about 101 degree from the SVOM optical axis, which is well outside the ECLAIRs field of view. But the burst emission has been detected by ECLAIRs through reflection onto the Earth atmosphere, and some of the low-energy emission of GRM is also detected through atmosphere reflection. 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: Wen-Jun Tan (IHEP) (tanwj(a)ihep.ac.cn) View this GCN Circular online at https://gcn.nasa.gov/circulars/41101. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39155] Fermi GRB 250716A: Global MASTER-Net observations report
by GCN Circulars 16 Jul '25

16 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41100 SUBJECT: Fermi GRB 250716A: Global MASTER-Net observations report DATE: 25/07/16 02:15:32 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-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 250716A ( Fermi GBM team, GCN 41099) errorbox 93 sec after notice time and 128 sec after trigger time at 2025-07-16 01:31:14 UT, with upper limit up to 20.3 mag. The observations began at zenith distance = 65 deg. The sun altitude is -51.6 deg. The galactic latitude b = -44 deg., longitude l = 255 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2937727 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 144 | 2025-07-16 01:31:14 | MASTER-SAAO | (04h 21m 01.64s , -48d 49m 17.3s) | C | 30 | 18.7 | 144 | 2025-07-16 01:31:15 | MASTER-SAAO | (04h 23m 46.59s , -49d 04m 32.8s) | C | 30 | 18.9 | 445 | 2025-07-16 01:36:01 | MASTER-SAAO | (04h 10m 39.54s , -50d 08m 38.2s) | C | 60 | 19.1 | 445 | 2025-07-16 01:36:01 | MASTER-SAAO | (04h 13m 29.24s , -50d 23m 52.1s) | C | 60 | 19.3 | 644 | 2025-07-16 01:39:20 | MASTER-SAAO | (04h 19m 15.27s , -48d 35m 54.2s) | C | 60 | 19.1 | 704 | 2025-07-16 01:39:20 | MASTER-SAAO | (04h 19m 15.27s , -48d 35m 54.2s) | C | 180 | 20.1 | Coadd 644 | 2025-07-16 01:39:20 | MASTER-SAAO | (04h 21m 59.51s , -48d 51m 08.0s) | C | 60 | 19.5 | 704 | 2025-07-16 01:39:20 | MASTER-SAAO | (04h 21m 59.50s , -48d 51m 08.0s) | C | 180 | 20.3 | Coadd 723 | 2025-07-16 01:40:39 | MASTER-SAAO | (04h 19m 15.21s , -48d 35m 54.7s) | C | 60 | 19.2 | 723 | 2025-07-16 01:40:39 | MASTER-SAAO | (04h 21m 59.40s , -48d 51m 08.0s) | C | 60 | 19.3 | 802 | 2025-07-16 01:41:58 | MASTER-SAAO | (04h 19m 15.12s , -48d 35m 55.6s) | C | 60 | 19.2 | 802 | 2025-07-16 01:41:58 | MASTER-SAAO | (04h 21m 59.30s , -48d 51m 08.5s) | C | 60 | 19.4 | 881 | 2025-07-16 01:43:17 | MASTER-SAAO | (04h 19m 14.99s , -48d 35m 56.7s) | C | 60 | 19.2 | 881 | 2025-07-16 01:43:17 | MASTER-SAAO | (04h 21m 59.18s , -48d 51m 09.2s) | C | 60 | 19.5 | 1549 | 2025-07-16 01:54:25 | MASTER-SAAO | (04h 23m 14.98s , -50d 08m 51.1s) | C | 60 | 19.2 | 1549 | 2025-07-16 01:54:25 | MASTER-SAAO | (04h 26m 05.15s , -50d 24m 04.2s) | C | 60 | 19.3 | 1642 | 2025-07-16 01:55:58 | MASTER-SAAO | (04h 10m 40.25s , -50d 08m 03.6s) | C | 60 | 19.2 | 1642 | 2025-07-16 01:55:58 | MASTER-SAAO | (04h 13m 30.51s , -50d 23m 15.5s) | C | 60 | 19.2 | 1737 | 2025-07-16 01:57:32 | MASTER-SAAO | (04h 24m 02.44s , -48d 13m 28.0s) | C | 60 | 19.2 | 1737 | 2025-07-16 01:57:33 | MASTER-SAAO | (04h 26m 45.90s , -48d 28m 40.4s) | C | 60 | 19.3 | 1830 | 2025-07-16 01:59:05 | MASTER-SAAO | (04h 35m 57.93s , -48d 13m 47.8s) | C | 60 | 19.2 | 1830 | 2025-07-16 01:59:06 | MASTER-SAAO | (04h 38m 41.15s , -48d 29m 00.3s) | C | 60 | 19.3 | 2023 | 2025-07-16 02:02:18 | MASTER-SAAO | (04h 13m 05.25s , -48d 15m 56.4s) | C | 60 | 19.2 | 2023 | 2025-07-16 02:02:19 | MASTER-SAAO | (04h 15m 48.99s , -48d 31m 08.2s) | C | 60 | 19.5 | 2117 | 2025-07-16 02:03:53 | MASTER-SAAO | (04h 14m 31.65s , -46d 20m 24.2s) | C | 60 | 19.1 | 2117 | 2025-07-16 02:03:53 | MASTER-SAAO | (04h 17m 09.42s , -46d 35m 36.2s) | C | 60 | 19.3 | 2210 | 2025-07-16 02:05:26 | MASTER-SAAO | (04h 26m 08.46s , -46d 21m 08.9s) | C | 60 | 19.1 | 2210 | 2025-07-16 02:05:26 | MASTER-SAAO | (04h 28m 46.06s , -46d 36m 20.9s) | C | 60 | 19.4 | 2504 | 2025-07-16 02:10:19 | MASTER-SAAO | (04h 23m 06.32s , -50d 07m 32.2s) | C | 60 | 19.3 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. View this GCN Circular online at https://gcn.nasa.gov/circulars/41100. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39154] GRB 250716A: Fermi GBM Final Real-time Localization
by GCN Circulars 16 Jul '25

16 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41099 SUBJECT: GRB 250716A: Fermi GBM Final Real-time Localization DATE: 25/07/16 01:39:42 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 01:29:06 UT on 16 Jul 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250716A (trigger 774322151.245036 / 250716062). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 65.7, Dec = -48.6 (J2000 degrees, equivalent to J2000 04h 22m, -48d 36'), with a statistical uncertainty of 1.0 degrees. The angle from the Fermi LAT boresight is 126.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250716062/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250716062/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250716062/… View this GCN Circular online at https://gcn.nasa.gov/circulars/41099. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39153] Fermi GRB 250715A: Global MASTER-Net observations report
by GCN Circulars 15 Jul '25

15 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41098 SUBJECT: Fermi GRB 250715A: Global MASTER-Net observations report DATE: 25/07/15 17:31:36 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-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 250715A ( Fermi GBM team, GCN 41097) errorbox 6778 sec after notice time and 6809 sec after trigger time at 2025-07-15 16:47:48 UT, with upper limit up to 19.0 mag. Observations started at twilight. The observations began at zenith distance = 73 deg. The sun altitude is -11.8 deg. The galactic latitude b = 72 deg., longitude l = 88 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2936965 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 6840 | 2025-07-15 16:47:48 | MASTER-SAAO | (13h 39m 24.98s , +41d 17m 09.8s) | C | 60 | 17.4 | 6840 | 2025-07-15 16:47:48 | MASTER-SAAO | (13h 41m 45.27s , +41d 01m 47.1s) | C | 60 | 17.4 | 6933 | 2025-07-15 16:49:21 | MASTER-SAAO | (13h 49m 58.86s , +41d 14m 56.3s) | C | 60 | 17.5 | 6933 | 2025-07-15 16:49:21 | MASTER-SAAO | (13h 52m 19.04s , +40d 59m 32.5s) | C | 60 | 17.5 | 7121 | 2025-07-15 16:52:30 | MASTER-SAAO | (13h 36m 16.48s , +39d 23m 35.6s) | C | 60 | 18.2 | 7121 | 2025-07-15 16:52:30 | MASTER-SAAO | (13h 38m 33.02s , +39d 08m 13.3s) | C | 60 | 18.0 | 7665 | 2025-07-15 17:01:34 | MASTER-SAAO | (13h 46m 43.77s , +39d 21m 51.3s) | C | 60 | 18.6 | 7665 | 2025-07-15 17:01:34 | MASTER-SAAO | (13h 49m 00.33s , +39d 06m 23.4s) | C | 60 | 18.6 | 7759 | 2025-07-15 17:03:07 | MASTER-SAAO | (13h 39m 31.43s , +41d 17m 22.0s) | C | 60 | 18.7 | 7759 | 2025-07-15 17:03:07 | MASTER-SAAO | (13h 41m 51.72s , +41d 01m 53.4s) | C | 60 | 18.6 | 7852 | 2025-07-15 17:04:41 | MASTER-SAAO | (13h 50m 06.50s , +41d 15m 29.6s) | C | 60 | 18.7 | 7852 | 2025-07-15 17:04:41 | MASTER-SAAO | (13h 52m 26.74s , +41d 00m 00.9s) | C | 60 | 18.7 | 8040 | 2025-07-15 17:07:48 | MASTER-SAAO | (13h 36m 21.22s , +39d 23m 06.4s) | C | 60 | 19.0 | 8040 | 2025-07-15 17:07:49 | MASTER-SAAO | (13h 38m 37.98s , +39d 07m 39.5s) | C | 60 | 18.9 | 8230 | 2025-07-15 17:10:58 | MASTER-SAAO | (13h 43m 46.68s , +43d 09m 56.5s) | C | 60 | 18.8 | 8230 | 2025-07-15 17:10:58 | MASTER-SAAO | (13h 46m 11.14s , +42d 54m 27.8s) | C | 60 | 18.5 | 8325 | 2025-07-15 17:12:33 | MASTER-SAAO | (13h 54m 46.94s , +43d 09m 33.9s) | C | 60 | 18.9 | 8325 | 2025-07-15 17:12:33 | MASTER-SAAO | (13h 57m 11.37s , +42d 54m 04.2s) | C | 60 | 18.8 | 8418 | 2025-07-15 17:14:06 | MASTER-SAAO | (13h 46m 44.39s , +39d 23m 28.0s) | C | 60 | 19.0 | 8418 | 2025-07-15 17:14:06 | MASTER-SAAO | (13h 49m 01.18s , +39d 07m 60.0s) | C | 60 | 19.0 | 8511 | 2025-07-15 17:15:40 | MASTER-SAAO | (13h 39m 34.83s , +41d 16m 33.4s) | C | 60 | 18.9 | 8511 | 2025-07-15 17:15:40 | MASTER-SAAO | (13h 41m 55.31s , +41d 01m 04.1s) | C | 60 | 18.8 | 8605 | 2025-07-15 17:17:13 | MASTER-SAAO | (13h 50m 14.55s , +41d 17m 42.6s) | C | 60 | 18.9 | 8605 | 2025-07-15 17:17:13 | MASTER-SAAO | (13h 52m 35.07s , +41d 02m 12.8s) | C | 60 | 19.0 | 8698 | 2025-07-15 17:18:46 | MASTER-SAAO | (13h 38m 42.15s , +39d 07m 59.9s) | C | 60 | 19.0 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. View this GCN Circular online at https://gcn.nasa.gov/circulars/41098. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39152] GRB 250713A: SVOM detection of a long burst
by GCN Circulars 15 Jul '25

15 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41078 SUBJECT: GRB 250713A: SVOM detection of a long burst DATE: 25/07/13 17:46:03 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> P. Maggi (ObAS), M. Brunet, L.Bouchet (IRAP), D. Gotz (CEA) report on behalf of the SVOM mission team: At 2025-07-13T17:06:26 UTC (T0), SVOM/ECLAIRs triggered and located the gamma-ray burst GRB 250713A (SVOM burst-id sb25071320). 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 7 alerts. IMT provided the alert with the best signal-to-noise-ratio in the image (SNR) of 14.04 in the [8-120] keV energy band over a time window of 40.96 seconds starting at 2025-07-13T17:06:02. The localization of the best alert is R.A., Dec. 336.9666, 38.7686 degrees (J2000) with a 90% confidence level (C.L.) radius of 5.84 arcmin (including systematic error of 2 arcmin added in quadrature). SVOM slewed to the burst. SVOM/MXT began observing the field at 2025-07-13T17:08:48 UTC, 142 seconds after T0. Using onboard processed data we found an uncatalogued X-ray source located at R.A., Dec. 336.9045, 38.7670 degrees: R.A. (J2000) = 22h27m37.09s Dec. (J2000) = 38d46m01.31s with a 90% C.L. radius of 55 arcseconds (including systematic error of 25 arcsec added in quadrature). This location is 2.90 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 Pierre Maggi: pierre.maggi(a)astro.unistra.fr. Please contact the BA by email if you require additional information. View this GCN Circular online at https://gcn.nasa.gov/circulars/41078. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39151] GRB 250715A: Fermi GBM Final Real-time Localization
by GCN Circulars 15 Jul '25

15 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41097 SUBJECT: GRB 250715A: Fermi GBM Final Real-time Localization DATE: 25/07/15 15:04:48 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 14:54:18 UT on 15 Jul 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250715A (trigger 774284063.63281 / 250715621). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 205.4, Dec = 41.2 (J2000 degrees, equivalent to J2000 13h 41m, 41d 12'), with a statistical uncertainty of 4.3 degrees. The angle from the Fermi LAT boresight is 92.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250715621/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250715621/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250715621/… View this GCN Circular online at https://gcn.nasa.gov/circulars/41097. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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