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

[vsnet-grb-info 38940] GRB 250702F: Swift detection of a burst with an optical counterpart
by GCN Circulars 02 Jul '25

02 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40894 SUBJECT: GRB 250702F: Swift detection of a burst with an optical counterpart DATE: 25/07/02 21:42:54 GMT FROM: Mike Siegel at PSU/Swift MOC <siegel(a)swift.psu.edu> N. J. Klingler (GSFC/UMBC/CRESSTII), A. D'Ai (INAF-IASFPA), R. Gupta (NASA GSFC), A. Y. Lien (U Tampa), T. M. Parsotan (GSFC) and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 21:06:43.27 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 250702F (trigger= 1329888). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 212.933, +16.699 which is RA(J2000) = 14h 11m 44s Dec(J2000) = 16d 41' 57" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a multi-peaked structure with a duration of about 70 sec. The peak count rate was ~4000 counts/sec (15-350 keV), at ~38 sec after the trigger. The XRT began observing the field at 21:08:11.7 UT, 88.5 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 212.9378, 16.7475 which is equivalent to: RA(J2000) = 14h 11m 45.07s Dec(J2000) = +16d 44' 51.0" with an uncertainty of 4.8 arcseconds (radius, 90% containment). This location is 175 arcseconds from the BAT onboard position, within the BAT error circle. No event data are yet available to determine the column density using X-ray spectroscopy. The initial flux in the 2.5 s image was 5.48e-09 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 150 seconds with the White filter starting 97 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at RA(J2000) = 14:11:44.69 = 212.93622 DEC(J2000) = +16:44:55.0 = 16.74861 with a 90%-confidence error radius of about 0.74 arc sec. This position is 6.7 arc sec. from the center of the XRT error circle. The estimated magnitude is 15.85 with a 1-sigma error of about 0.14. No correction has been made for the expected extinction corresponding to E(B-V) of 0.017. This burst is spatially and temporally coincident with the burst reported by Fermi GBM (GCN Circ. 40892). Burst Advocate for this burst is N. J. Klingler (noelklin AT umbc.edu) Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/) View this GCN Circular online at https://gcn.nasa.gov/circulars/40894. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38939] Swift GRB250702.88: Global MASTER-Net observations report
by GCN Circulars 02 Jul '25

02 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40893 SUBJECT: Swift GRB250702.88: Global MASTER-Net observations report DATE: 25/07/02 21:36:54 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) was pointed to the Swift GRB250702.88 (trigger No 1329888,14h 11m 43.92s , +16d 41m 56.4s, R=0.05) errorbox 1057 sec after notice time and 1076 sec after trigger time at 2025-07-02 21:24:39 UT, with upper limit up to 16.9 mag. The observations began at zenith distance = 68 deg. The sun altitude is -70.5 deg. The galactic latitude b = 68 deg., longitude l = 8 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2923573 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 1106 | MASTER-SAAO | P/ | 60 | 16.2 | 1106 | MASTER-SAAO | P\\ | 60 | 16.2 | 1185 | MASTER-SAAO | P/ | 60 | 16.8 | 1185 | MASTER-SAAO | P\\ | 60 | 16.7 | 1264 | MASTER-SAAO | P/ | 60 | 16.9 | 1264 | MASTER-SAAO | P\\ | 60 | 16.8 | 1343 | MASTER-SAAO | P/ | 60 | 13.8 | The observation and reduction will continue. The message may be cited. View this GCN Circular online at https://gcn.nasa.gov/circulars/40893. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38938] GRB 250702F: Fermi GBM Final Real-time Localization
by GCN Circulars 02 Jul '25

02 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40892 SUBJECT: GRB 250702F: Fermi GBM Final Real-time Localization DATE: 25/07/02 21:17:16 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 21:06:43 UT on 2 Jul 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250702F (trigger 773183208.102296 / 250702880). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 215.8, Dec = 16.6 (J2000 degrees, equivalent to J2000 14h 23m, 16d 36'), with a statistical uncertainty of 2.2 degrees. The angle from the Fermi LAT boresight is 43.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250702880/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250702880/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250702880/… View this GCN Circular online at https://gcn.nasa.gov/circulars/40892. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38937] Fermi GBM Triggers 250702B, C, D and E are likely from the same source
by GCN Circulars 02 Jul '25

02 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40891 SUBJECT: Fermi GBM Triggers 250702B, C, D and E are likely from the same source DATE: 25/07/02 19:04:27 GMT FROM: eliza.neights(a)gmail.com E. Neights (GWU, NASA GSFC), O.J. Roberts (USRA, NASA MSFC), E. Burns (LSU), P. Veres (UAH) report on behalf of the Fermi-GBM Team: At 13:09:02.03 UT, Fermi GBM triggered on GRB 250702D and was initially localized to an RA and Dec of 292.9 and 3.6 (19h, 31m, +03,33’; J2000), with an error of 14.7 deg. The light curve shows several peaks occurring over ~60 seconds. Since then, an additional three bursts have triggered GBM with similar lightcurve characteristics and localizations. The trigger times and localizations are summarized as follows: GRB Name MET (s) Time (UT) RA (deg) Dec (deg) Err (deg) 250702E 773166098 16:21:33.07 286.8 -17.7 11.6 (GCN 40890) 250702C 773160576 14:49:31.91 270.3 1.4 12.7 (GCN 40885) 250702B 773157370 13:56:05.77 286.0 -8.7 7.8 (GCN 40883) 250702D 773154547 13:09:02.03 292.9 3.6 14.7 (GCN 40886) Despite the similar position lying close to or on the galactic plane, we observe photons in the BGO up to 1 MeV, with the majority of the photons occurring in the 50-300 keV range, which suggest the source may not be a typical galactic source and might be an ultra-long GRB or another source class. If a GRB origin is confirmed, it is 11.5 ks long, making it one of the longest ultra-long GRBs detected. The combined GBM skymap can be found here: https://zenodo.org/records/15793558. The skymaps are all associated with each other with confidence between 89.2 and 98.5%. There were no joint-GW detections during these triggered times. We strongly suggest follow-up of the region to determine the nature of the source over multiple wavelengths. View this GCN Circular online at https://gcn.nasa.gov/circulars/40891. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38936] Fermi GBM Triggers 250702B, C, D and E are likely from the same source
by GCN Circulars 02 Jul '25

02 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40891 SUBJECT: Fermi GBM Triggers 250702B, C, D and E are likely from the same source DATE: 25/07/02 19:04:27 GMT FROM: eliza.neights(a)gmail.com E. Neights (GWU, NASA GSFC), O.J. Roberts (USRA, NASA MSFC), E. Burns (LSU), P. Veres (UAH) report on behalf of the Fermi-GBM Team: At 13:09:02.03 UT, Fermi GBM triggered on GRB 250702D and was initially localized to an RA and Dec of 292.9 and 3.6 (19h, 31m, +03,33’; J2000), with an error of 14.7 deg. The light curve shows several peaks occurring over ~60 seconds. Since then, an additional three bursts have triggered GBM with similar lightcurve characteristics and localizations. The trigger times and localizations are summarized as follows: GRB Name MET (s) Time (UT) RA (deg) Dec (deg) Err (deg) 250702E 773166098 16:21:33.07 286.8 -17.7 11.6 (GCN 40890) 250702C 773160576 14:49:31.91 270.3 1.4 12.7 (GCN 40885) 250702B 773157370 13:56:05.77 286.0 -8.7 7.8 (GCN 40883) 250702D 773154547 13:09:02.03 292.9 3.6 14.7 (GCN 40886) Despite the similar position lying close to or on the galactic plane, we observe photons in the BGO up to 1 MeV, with the majority of the photons occurring in the 50-300 keV range, which suggest the source may not be a typical galactic source and might be an ultra-long GRB or another source class. If a GRB origin is confirmed, it is 11.5 ks long, making it one of the longest ultra-long GRBs detected. The combined GBM skymap can be found here: https://zenodo.org/records/15793558. The skymaps are all associated with each other with confidence between 89.2 and 98.5%. There were no joint-GW detections during these triggered times. We strongly suggest follow-up of the region to determine the nature of the source over multiple wavelengths. View this GCN Circular online at https://gcn.nasa.gov/circulars/40891. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38935] GRB 250702E: Fermi GBM Final Real-time Localization
by GCN Circulars 02 Jul '25

02 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40890 SUBJECT: GRB 250702E: Fermi GBM Final Real-time Localization DATE: 25/07/02 16:32:10 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 16:21:33 UT on 2 Jul 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250702E (trigger 773166098.071902 / 250702682). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 286.8, Dec = -17.7 (J2000 degrees, equivalent to J2000 19h 07m, -17d 41'), with a statistical uncertainty of 11.6 degrees. The angle from the Fermi LAT boresight is 106.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250702682/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250702682/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250702682/… View this GCN Circular online at https://gcn.nasa.gov/circulars/40890. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38934] Konus-Wind detection of GRB 250627A
by GCN Circulars 02 Jul '25

02 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40889 SUBJECT: Konus-Wind detection of GRB 250627A DATE: 25/07/02 16:17:20 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 short-duration GRB 250627A (SVOM-GRM detection: Wang et al., GCN 40871; Insight-HXMT detection: Wang et al., GCN 40872; IPN triangulation: Kozyrev et al., GCN 40888) triggered Konus-Wind at T0=60377.861 s UT (16:46:17.861). The burst light curve shows a multipeaked structure which starts at ~T0-0.3 s and has a total duration of ~1.1 s. The emission is seen up to ~10 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB250627_T60377/ As observed by Konus-Wind, the burst had a fluence of 9.65(-1.16,+1.29)x10^-6 erg/cm2, and a 16-ms peak flux, measured from T0+0.420 s, of 2.60(-0.49,+0.52)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+8.448 s) is best fit in the 20 keV - 10 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -0.31(-0.21,+0.25) and Ep = 874(-128,+160) keV (chi2 = 73/76 dof). Fitting by a GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -2.7 (chi2 = 73/75 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/40889. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38933] IPN triangulation of GRB 250627A (short)
by GCN Circulars 02 Jul '25

02 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40888 SUBJECT: IPN triangulation of GRB 250627A (short) DATE: 25/07/02 16:13:38 GMT FROM: Anna Ridnaia at Ioffe Institute <ridnaia(a)mail.ioffe.ru> A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin on behalf of the HEND/Mars Odyssey team, A. Ridnaia, D. Frederiks, A. Lysenko, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, E. Burns on behalf of the IPN, Y. Zhang, C. Wang, S. Xiong, J. Wei, and B. Cordier on behalf of the SVOM-GRM team, and W. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr, and A.S. Gardner on on behalf of the GRS-Odyssey GRB team, report: The short-duration GRB 250627A (SVOM-GRM detection: Wang et al., GCN 40871; Insight-HXMT detection: Wang et al., GCN 40872) was detected by SVOM (GRM), Insight-HXMT, Konus-Wind, and Mars-Odyssey (HEND) at about 60378 s UT (16:46:18). We have triangulated it to a preliminary, 3 sigma error box whose coordinates are: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 90.764 (06h 03m 03s) +10.097 (+10d 05' 48") Corners: 90.676 (06h 02m 42s) +10.618 (+10d 37' 04") 90.803 (06h 03m 13s) +9.585 ( +9d 35' 07") 90.855 (06h 03m 25s) +9.577 ( +9d 34' 37") 90.727 (06h 02m 55s) +10.609 (+10d 36' 32") --------------------------------------------- The error box area is 185 sq. arcmin, and its maximum dimension is 1.1 deg (the minimum one is 2.4 arcmin). The Sun distance was 14 deg. This localization may be improved. A triangulation map and HEALPix FITS file are posted at http://www.ioffe.ru/LEA/GRBs/GRB250627_T60377/IPN The HEALPix triangulation map is the multi-order HEALPix in units of probability density. The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular. View this GCN Circular online at https://gcn.nasa.gov/circulars/40888. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38932] GRB 250702A: Fermi GBM Detection
by GCN Circulars 02 Jul '25

02 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40887 SUBJECT: GRB 250702A: Fermi GBM Detection DATE: 25/07/02 15:35:45 GMT FROM: Christian Malacaria at INAF-OAR <cmalacaria.astro(a)gmail.com> C. Malacaria (INAF-OAR) and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team: "At 09:54:07.56 UT on 02 July 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250702A (trigger 773142852/250702413). The Fermi-GBM position was reported in GCN 40883 (Fermi GBM Team 2025). The angle from the Fermi LAT boresight is 56 degrees. The GBM light curve consists of a single bright emission episode with a duration (T90) of about 52.7 s (50-300 keV). The time-averaged spectrum from T0 to T0+69 s is best fit by a Band function with Epeak= 242 +/- 9 keV, alpha =-0.57 +/- 0.03 and beta =-2.6 +/- 0.2. A power law function with an exponential high-energy cutoff fits the spectrum equally well with a power law index of -0.61 +/- 0.02 and a cutoff energy, parameterized as Epeak, of 262 +/- 7 keV. The event fluence (10-1000 keV) in this time interval is (3.84 +/- 0.08)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+3.9 s in the 10-1000 keV band is 12.8 +/- 0.3 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/40887. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38931] GRB 250702D: Fermi GBM Final Localization Correction
by GCN Circulars 02 Jul '25

02 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40886 SUBJECT: GRB 250702D: Fermi GBM Final Localization Correction DATE: 25/07/02 15:19:41 GMT FROM: eliza.neights(a)gmail.com The Fermi GBM team reports the detection of a likely LONG GRB "At 13:09:02.03 UT on 02 July 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250702D (trigger 773154547/250702548). This trigger was initially classified as Below horizon by the flight software, but is in fact a GRB. The on-ground calculated location, using the Fermi GBM trigger data, is RA = 292.86, Dec = 3.55 (J2000 degrees, equivalent to J2000 19h 31m, +3d 32'), with a statistical uncertainty of 14.69 degrees. The angle from the Fermi LAT boresight is 92 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250702548/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250702548/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250702548/…" View this GCN Circular online at https://gcn.nasa.gov/circulars/40886. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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