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

[vsnet-grb-info 38847] GRB 250620A: SVOM/GRM observation of a short burst
by GCN Circulars 22 Jun '25

22 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40806 SUBJECT: GRB 250620A: SVOM/GRM observation of a short burst DATE: 25/06/22 05:55:18 GMT FROM: Chenwei Wang at IHEP <cwwang(a)ihep.ac.cn> SVOM/GRM team: Chen-Wei Wang, Shi-Jie Zheng, Yue Huang, Shao-Lin Xiong, Shuang-Nan Zhang (IHEP) SVOM/ECLAIRs team: Ulysse Jacob (LUPM) Report on behalf of the SVOM team: SVOM/GRM was triggered in-flight by a bright burst GRB 250620A (SVOM trigger reference: sb25062002) at 2025-06-20T08:05:19 UTC (T0), which is also detected by Fermi/GBM (Fermi GBM Team, GCN#40791) and Swift/BAT (James DeLaunay et al., GCN#40796). With the event-by-event data downloaded through the X-band ground station, the GRM light curve shows that this burst consists of a narrow spike with a T90 of 0.15 +/-0.05 s in the 15-5000 keV band. The SVOM/GRM light curve can be found here: https://www.bursthub.cn//admin/static/svgrb250620A.png In addition, the position of this burst, as determined by Fermi/GBM (RA= 46.2, DEC= 65.8, GCN#40791), is located at about 111 degrees from the SVOM optical axis, which is outside the ECLAIRs field of view. With this localization, the time-averaged spectrum from T0-0.2 to T0 s is best fitted by a power law function with an exponential high-energy cutoff. The power law index is -1.64 +0.25/-0.19 and the cutoff energy, parameterized as Epeak, is 1310 +1780/-780 keV. The event fluence (10-1000 keV) in this time interval is (8.36 +0.89/-0.87)E-07 erg/cm^2. The localization of GRB 250620A in the 'Amati' relation diagram is shown at: https://www.bursthub.cn//admin/static/grb250620A_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/40806. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38846] GRB250620A: Fermi GBM Observation
by GCN Circulars 21 Jun '25

21 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40805 SUBJECT: GRB250620A: Fermi GBM Observation DATE: 25/06/21 23:52:54 GMT FROM: rhamburg(a)usra.edu R. Hamburg (USRA) and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team: "At 08:05:18.94 UT on 20 June 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250620A (trigger 772099523/250620337) which was also detected by Swift/BAT-GUANO (DeLaunay et al. 2025, GCN 40796). The angle from the Fermi LAT boresight is 164 degrees. The GBM light curve two pulses with a duration (T90) of about 12 s (50-300 keV). The time-averaged spectrum from T0-0.3 to T0+10 s is best fit by a simple power law function with index -1.6 +/- 0.2. The event fluence (10-1000 keV) in this time interval is (1.1 +/- 1.3)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+3.8 s in the 10-1000 keV band is 9 +/- 2 ph/s/cm^2. A Band function fits the spectrum equally well with Epeak = 2000 +/- 200 keV, alpha = -1.08 +/- 0.03 and beta = -2.44 +/- 0.09. 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/40805. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38845] GRB 250617B: Calapai Observatory, Massa S. Giorgio (Messina), optical observation.
by GCN Circulars 21 Jun '25

21 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40804 SUBJECT: GRB 250617B: Calapai Observatory, Massa S. Giorgio (Messina), optical observation. DATE: 25/06/21 21:08:57 GMT FROM: Giovanni Calapai at Calapai Astronomical Observatory, Massa S. Giorgio, Messina, Italy <giovannicalapai(a)tiscali.it> Giovanni Calapai at Calapai Astronomical Observatory, Massa S. Giorgio, (Messina) Italy Member of: GRB/UAI Gamma Ray Burst Section of Unione Astrofili Italiani. Report: We observed the field of GRB 250617B detected by Swift/BAT (Page et al. GCN 40760) with the 11 inches Schmidt-Cassegrain (Celestron 11) telescope F/D=6,3. The observations were started at 2025-06-17 23:10:55 UT (approximately 2.15 hours after burst) stacking a two consecutive sets of unfiltered CCD image. The observations were carried out with visibility disturbed by passing clouds. The OT was detected at the following position: RA (J2000.0) 22h 11m 35.21s +/- 0.02 Decl. (J2000.0) +32° 43' 57.6" +/- 1.1 The results of our photometry are: Observation Mid-Time T-T0 (hr) Exposure Filter Mag. S/N Mag. err. 2025-06-18 00:05:21 UT 3.06 90x60s CR 19.24 9.1 +/-0.17 2025-06-18 01:47:28 UT 4.76 88x60s CR 20.75 3.4 +/-0.30 Given the low S/N for the OT of second set, we cannot completely rule out it being due to background fluctuation. Along the span of our observations and within our uncertainties, the afterglow evolves in agreement with a power-law decay index of ~0.89. Magnitude was calibrated with the nearby PanSTARRS stars converted using Lupton (2005) equations. No correction for galactic dust extinction was applied. Our observations are consistent with other already reported Moskvitin et al. (GCN 40761); Jelinek et al. (GCN 40762); Kumar et al. (GCN 40768); Lipunov et al. (GCN 40769); Grossan et al. (GCN 40771); Ma et al. (GCN 40772); Williams et al. (GCN 40773); Schneider et al. (GCN 40774); Antier et al. (GCN 40775); Corcoran et al. (GCN 40776); Turpin et al. (GCN 40777); Siegel et al. (GCN 40778); Pankov et al. (GCN 40783); Gendreau-Distler et al. (GCN 40789). The message may be cited. View this GCN Circular online at https://gcn.nasa.gov/circulars/40804. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38844] Fermi GRB 250621A: Global MASTER-Net observations report
by GCN Circulars 21 Jun '25

21 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40803 SUBJECT: Fermi GRB 250621A: Global MASTER-Net observations report DATE: 25/06/21 02:30:51 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 (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 250621A ( Fermi GBM team, GCN 40801) errorbox 79 sec after notice time and 111 sec after trigger time at 2025-06-21 01:16:46 UT, with upper limit up to 18.2 mag. The observations began at zenith distance = 77 deg. The sun altitude is -45.4 deg. The galactic latitude b = 10 deg., longitude l = 248 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2910652 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 122 | 2025-06-21 01:16:46 | MASTER-OAFA | (08h 35m 57.13s , -26d 43m 55.5s) | C | 20 | 17.4 | 161 | 2025-06-21 01:17:21 | MASTER-OAFA | (08h 46m 34.40s , -23d 40m 16.6s) | C | 30 | 17.8 | 202 | 2025-06-21 01:17:57 | MASTER-OAFA | (08h 46m 34.42s , -23d 40m 16.3s) | C | 40 | 17.9 | 253 | 2025-06-21 01:18:43 | MASTER-OAFA | (08h 46m 34.45s , -23d 40m 16.4s) | C | 50 | 18.0 | 315 | 2025-06-21 01:19:40 | MASTER-OAFA | (08h 46m 34.42s , -23d 40m 15.2s) | C | 60 | 17.9 | 386 | 2025-06-21 01:20:46 | MASTER-OAFA | (08h 46m 34.44s , -23d 40m 15.4s) | C | 70 | 18.2 | 472 | 2025-06-21 01:22:02 | MASTER-OAFA | (08h 46m 34.52s , -23d 40m 15.8s) | C | 90 | 18.2 | 573 | 2025-06-21 01:23:38 | MASTER-OAFA | (08h 46m 34.55s , -23d 40m 15.7s) | C | 100 | 18.2 | 702 | 2025-06-21 01:25:32 | MASTER-OAFA | (08h 39m 15.15s , -24d 49m 47.5s) | C | 130 | 18.1 | 848 | 2025-06-21 01:27:48 | MASTER-OAFA | (08h 39m 15.35s , -24d 49m 48.3s) | C | 150 | 17.9 | 1019 | 2025-06-21 01:30:24 | MASTER-OAFA | (08h 39m 15.58s , -24d 49m 49.7s) | C | 180 | 17.8 | 1205 | 2025-06-21 01:33:30 | MASTER-OAFA | (08h 39m 15.88s , -24d 49m 51.5s) | C | 180 | 17.6 | 1392 | 2025-06-21 01:36:36 | MASTER-OAFA | (08h 39m 16.16s , -24d 49m 53.1s) | C | 180 | 17.5 | 1578 | 2025-06-21 01:39:42 | MASTER-OAFA | (08h 39m 16.38s , -24d 49m 59.7s) | C | 180 | 17.2 | 1763 | 2025-06-21 01:42:48 | MASTER-OAFA | (08h 39m 16.61s , -24d 50m 07.5s) | C | 180 | 16.8 | 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/40803. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38843] GRB 250619B: Fermi GBM Observation
by GCN Circulars 21 Jun '25

21 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40802 SUBJECT: GRB 250619B: Fermi GBM Observation DATE: 25/06/21 01:38:07 GMT FROM: Jacob Smith at Fermi-GBM Team <jrs0118(a)uah.edu> Jacob Smith (UAH) and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team: At 23:36:17.17 UT on 19 June 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250619B (trigger 772068982/250619984). which was also detected by Swift/BAT-GUANO (J. DeLaunay et al. 2025, GCN 40795). The Fermi GBM on-ground location is consistent with the Swift/BAT-GUANO position. The angle from the Fermi LAT boresight is 48 degrees. The GBM light curve consists of a double emission episode with a duration (T90) of about 29 s (50-300 keV). The time-averaged spectrum from T0-1 to T0+28.7 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -1.1 +/- 0.2 and the cutoff energy, parameterized as Epeak, is 67 +/- 9 keV. A Band function fits the spectrum equally well with Epeak = 57 +/- 13 keV, alpha = -1 +/- 0.4 and beta = -2.5 +/- 0.4. The event fluence (10-1000 keV) in this time interval is (1.4 +/- 0.1)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0-0.32 s in the 10-1000 keV band is 2.2 +/- 0.2 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/40802. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38842] GRB 250621A: Fermi GBM Final Real-time Localization
by GCN Circulars 21 Jun '25

21 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40801 SUBJECT: GRB 250621A: Fermi GBM Final Real-time Localization DATE: 25/06/21 01:25:28 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 01:14:55 UT on 21 Jun 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250621A (trigger 772161300.203902 / 250621052). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 129.7, Dec = -25.1 (J2000 degrees, equivalent to J2000 08h 38m, -25d 06'), with a statistical uncertainty of 1.9 degrees. The angle from the Fermi LAT boresight is 50.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250621052/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250621052/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250621052/… View this GCN Circular online at https://gcn.nasa.gov/circulars/40801. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38841] GRB 250620B: Swift/BAT-GUANO localization skymap of a burst
by GCN Circulars 21 Jun '25

21 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40800 SUBJECT: GRB 250620B: Swift/BAT-GUANO localization skymap of a burst DATE: 25/06/21 00:30:05 GMT FROM: Samuele Ronchini at PSU <sjs8171(a)psu.edu> Samuele Ronchini (PSU), James DeLaunay (PSU), Aaron Tohuvavohu (Caltech), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC), Maia Williams (PSU) report: Swift/BAT did not localize GRB 250620B onboard (T0: 2025-06-20T13:22:56.94 UTC, Fermi/GBM GCN 40792) The Fermi notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1). Upon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 200 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground. The BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), performed on the temporal window [T0-20 s, T0+20 s], detects the burst with a sqrt(TS) of 13.83 in a 4.096 s analysis time bin, starting at T0 - 1.024 s. Using the NITRATES analysis, parameter estimation was performed to obtain the localization of this burst in the form of a HEALPIX Multi-Order Coverage (MOC) skymap. This localization accounts for both statistical and systematic errors. More details in the creation and calibration of these maps will soon be published (DeLaunay et al. 2025. in prep) The 90% credible area is 8,562 deg2 and the 50% credible area is 2,685 deg2. The integrated probability inside the coded field of view is 8%. The NITRATES skymap is consistent with the Fermi localization reported in the final position notice (GCN 40792). The combined Fermi/GBM+NITRATES 90% credible area is 158 deg2 and the 50% credible area is 51 deg2. A plot of the probability skymap can be viewed here: [skymap_plot](https://guano.swift.psu.edu/trigger_report?id=772118612/#:~:te… The probability skymap and joint skymap files can be downloaded from the links here [skymap_fits_file](https://guano.swift.psu.edu/files/772118612/0_n_PROBMAP) [joint_skymap_fits_file](https://guano.swift.psu.edu/files/772118612/0_n_JOI… Instructions on how to read and manipulate this map can be found here: https://guano.swift.psu.edu/documentation More details about this burst can be found on the trigger report page here: https://guano.swift.psu.edu/trigger_report?id=772118612 GUANO is a fully autonomous, extremely low latency, spacecraft commanding pipeline designed for targeted recovery of BAT event mode data around the times of compelling astrophysical events to enable more sensitive GRB searches. A live reporting of Swift/BAT event data recovered by GUANO can be found at: https://www.swift.psu.edu/guano/ View this GCN Circular online at https://gcn.nasa.gov/circulars/40800. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38840] GRB250620C: Fermi GBM Observation
by GCN Circulars 20 Jun '25

20 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40799 SUBJECT: GRB250620C: Fermi GBM Observation DATE: 25/06/20 23:48:00 GMT FROM: oindabimukherjee(a)gmail.com O. Mukherjee (USRA) reports on behalf of the Fermi Gamma-ray Burst Monitor Team: "At 16:07:09.92 UT on 20 June 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB250620C (trigger 772128434/250620672). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 142.61, Dec = 54.96 (J2000 degrees, equivalent to J2000 9h 30m, +54d 57'), 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 124 degrees. The GBM light curve consists of multiple emission episodes with a duration (T90) of about 32 s (50-300 keV). The time-averaged spectrum from T0 to T0+35.7 s is best fit by a Band function with Epeak= 371 +/- 15 keV, alpha = -0.93 +/- 0.02 and beta = -2.6 +/- 0.2. The event fluence (10-1000 keV) in this time interval is (6.64 +/- 0.07)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+0.96 s in the 10-1000 keV band is 50.1 +/- 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/40799. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38839] GRB 260506A - SVOM/ECLAIRs Refined analysis
by GCN Circulars 20 Jun '25

20 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40798 SUBJECT: GRB 260506A - SVOM/ECLAIRs Refined analysis DATE: 25/06/20 22:04:35 GMT FROM: sebastien.guillot(a)irap.omp.eu Authors: S. Guillot (IRAP), F. Cangemi, A. Coleiro (APC), M.-G. Bernardini (INAF-OAB, LUPM), O. Godet (IRAP), Chenwei WANG (IHEP), Lin LAN (NAOC) Using the event-by-event data downloaded through the X-band ground station, we report further analysis of ECLAIRs observations of GRB 250506A (SVOM burst-id sb25050601). The burst that triggered ECLAIRs onboard (GCN 40358) consists of a single pulse with a duration of T90 = 6.4 +1.0/-0.6 s in the 4-120 keV energy band. We note that ECLAIRs only saw the first peak of this GRB since the source passed behind the Earth during the burst. Therefore, this T90 value is only for the first peak, and is shorter than those measured by Fermi/GBM (GCN 40362) and GECAM (GCN 40396). The time-averaged spectrum of the burst from T0 + 4.12 sec to T0 + 12.12 sec (T0 = 2025-05-06T02:23:16.88) in the energy range 5-115 keV is best fit by a broken power-law model with a break energy of 14.2 +3.8/-1.9 keV, a photon index of -0.3 +/- 0.2 before the break, and of -0.97 +0.06/-0.08 after the break. The photon index after the break is broadly consistent with the PL index (50-300 keV) reported from the Fermi/GBM analysis (GCN 40362). With this model, the total 4-120 keV fluence, assuming the T90 measured, is 1.75 +0.28/-0.5 x 10^-6 erg/cm^2. All the quoted errors are at the 90% confidence level. Other models (power law, cutoff power law, blackbody + power law, gamma-ray burst continuum) do not satisfactorily fit the data. The comparison of the power-law and broken power-law fits yields a spectral break significance of 5.1 sigma (Gaussian two-sided). We note that the calibration of SVOM/ECLAIRs is undergoing thus these results are preliminary. 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. ECLAIRs was developed jointly by CNES, CEA-IRFU, CNRS-IRAP, CNRS-APC. The SVOM/ECLAIRs point of contact for this burst is: Sébastien Guillot (IRAP) (sebastien.guillot at irap.omp.eu) View this GCN Circular online at https://gcn.nasa.gov/circulars/40798. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38838] The EP-WXT trigger 01709179071 is likely a flaring star
by GCN Circulars 20 Jun '25

20 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40797 SUBJECT: The EP-WXT trigger 01709179071 is likely a flaring star DATE: 25/06/20 20:59:28 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> X. Mao, Y. J. Song, T. Zhao, Z. X. Ling (NAO, CAS) on behalf of the Einstein Probe (EP) team: The EP-WXT trigger 01709179071 at the time of 2025-06-20T19:46:46, is likely a stellar flare associated with 2MASS J21370885-6036054. The estimated flux of the flare is around 1e-10 erg/s/cm^2 in 0.5-4.0 keV, corresponding to an X-ray luminosity of around 2.4e31 erg/s. 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/40797. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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