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

[vsnet-grb-info 39070] Fermi-LAT Gamma-ray Observations of IceCube-250706A
by GCN Circulars 07 Jul '25

07 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41020 SUBJECT: Fermi-LAT Gamma-ray Observations of IceCube-250706A DATE: 25/07/07 20:54:25 GMT FROM: Simone Garrappa at Weizmann Institute of Science <simone.garrappa(a)weizmann.ac.il> S. Garrappa (Weizmann Institute of Science), L. Pfeiffer (Univ. of Wuerzburg), S. Buson (DESY, Univ. of Wuerzburg) and C. Bartolini (INFN Bari) on behalf of the Fermi-LAT collaboration: We report an analysis of observations of the vicinity of the high-energy IC250706A neutrino event (GCN 40994) with all-sky survey data from the Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope. The IceCube event was detected on 2025-07-06 at 13:14:40.04 UTC (T0) with J2000 position RA = 266.00 (+0.57, -0.59) deg, Decl. = 38.97 (+0.49, -0.47) deg 90% PSF containment (J2000). No cataloged gamma-ray sources are found within the 90% IC250706A localization error (4FGL-DR4; The Fourth Fermi-LAT catalog Data Release 4, The Fermi-LAT collaboration 2023, arXiv:2307.12546). We searched for the existence of intermediate (days to years) timescale emission from a new gamma-ray transient source. Preliminary analysis indicates no significant (>5sigma) new excess emission (> 100 MeV) within the IC250706A 90% confidence localization. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IC250706A best-fit position, the >100 MeV flux upper limit (95% confidence) is <5.0e-10 ph cm^-2 s^-1 for ~16-years (2008-08-04 / T0), <5.0e-09 (<9.2e-08) ph cm^-2 s^-1 for a 1-month (1-day) integration time before T0. Since Fermi normally operates in an all-sky scanning mode, regular monitoring of this source will continue. For this source, the Fermi-LAT contact person is S. Garrappa (simone.garrappa at weizmann.ac.il). The Fermi LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden. View this GCN Circular online at https://gcn.nasa.gov/circulars/41020. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39069] GRB 250706B/C: Fermi-LAT detection
by GCN Circulars 07 Jul '25

07 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41019 SUBJECT: GRB 250706B/C: Fermi-LAT detection DATE: 25/07/07 20:48:10 GMT FROM: N. Di Lalla at Stanford University <niccolo.dilalla(a)stanford.edu> F. Longo (University and INFN, Trieste), N. Di Lalla (Stanford Univ.), A. Holzmann Airasca (UniTrento and INFN Bari), E. Bissaldi (Politecnico and INFN Bari), R. Gupta (NASA/GSFC), S. Lopez (CNRS / IN2P3) and J. Racusin (NASA/GSFC) report on behalf of the Fermi-LAT Collaboration: On July 06, 2025, Fermi-LAT detected high-energy emission from GRB 250706B/C, which was also detected by Konus-Wind (named GRB 250706C in GCN 41013), SVOM/Eclairs (named GRB 250706B in GCN 40989), Swift/XRT (named GRB 250706B in GCN 40996) and Swift/UVOT (named GRB 250706B in GCN 41015). The best LAT on-ground location is found to be: RA, Dec = 41.17, -50.04 (J2000) with an error radius of 0.07 deg (90 % containment, statistical error only). This was 87 deg from the LAT boresight at the time of the Konus-Wind trigger (T0 = 16:45:22.626 UT). The data from the Fermi-LAT shows a significant increase in the event rate starting about 600 s after the Konus-Wind trigger, as soon as the GRB position entered the LAT field of view. The LAT emission is spatially and temporally correlated with both the Konus-Wind (GRB 250706C) and SVOM (GRB 250706B) emission with high significance, which are therefore to be considered part of the same burst. The photon flux above 100 MeV in the time interval 600 - 10000 s after the Konus-Wind trigger is (3.52 ± 0.59) E-6 ph/cm2/s. The estimated photon index above 100 MeV is -1.87 ± 0.12. The highest-energy photon is a 21 GeV event which is observed ~ 8 ks seconds after the Konus-Wind trigger. The Fermi-LAT point of contact for this burst is Dimakatso Maheso (d.j.maheso(a)gmail.com) The Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden. View this GCN Circular online at https://gcn.nasa.gov/circulars/41019. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39068] IceCube Alert 250706.55: Global MASTER-Net observations report
by GCN Circulars 07 Jul '25

07 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41018 SUBJECT: IceCube Alert 250706.55: Global MASTER-Net observations report DATE: 25/07/07 19:39:20 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) was pointed to the IceCube Alert 250706.55 (trigger No 37015490,17h 43m 54.48s , +38d 59m 38.4s, R=0.6) errorbox 58565 sec after notice time and 58603 sec after trigger time at 2025-07-07 05:31:23 UT, with upper limit up to 18.5 mag. The observations began at zenith distance = 76 deg. The sun altitude is -75.7 deg. MASTER-Tavrida robotic telescope located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the IceCube Alert 250706.55 errorbox 1 days 20760 sec after notice time and 1 days 20797 sec after trigger time at 2025-07-07 19:01:17 UT, with upper limit up to 14.9 mag. Observations started at twilight. The observations began at zenith distance = 16 deg. The sun altitude is -13.3 deg. The galactic latitude b = 29 deg., longitude l = 65 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2927494 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 58633 | 2025-07-07 05:31:23 | MASTER-OAFA | (17h 52m 43.98s , +39d 48m 07.5s) | C | 60 | 17.9 | 58693 | 2025-07-07 05:31:23 | MASTER-OAFA | (17h 52m 43.98s , +39d 48m 07.6s) | C | 180 | 18.5 | Coadd 58708 | 2025-07-07 05:32:38 | MASTER-OAFA | (17h 52m 37.32s , +39d 47m 39.5s) | C | 60 | 17.9 | 58782 | 2025-07-07 05:33:52 | MASTER-OAFA | (17h 52m 36.76s , +39d 48m 41.6s) | C | 60 | 17.9 | 58857 | 2025-07-07 05:35:07 | MASTER-OAFA | (17h 52m 42.61s , +39d 47m 42.4s) | C | 60 | 17.9 | 58931 | 2025-07-07 05:36:20 | MASTER-OAFA | (17h 52m 35.82s , +39d 46m 43.9s) | C | 60 | 17.8 | 59005 | 2025-07-07 05:37:34 | MASTER-OAFA | (17h 52m 41.21s , +39d 47m 10.1s) | C | 60 | 17.8 | 107228 | 2025-07-07 19:01:17 | MASTER-Tavrida | (17h 43m 55.10s , +39d 01m 11.7s) | C | 60 | 14.9 | 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/41018. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39067] GRB 250704A: SVOM/COLIBRÍ (FM-GFT) optical observations
by GCN Circulars 07 Jul '25

07 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41017 SUBJECT: GRB 250704A: SVOM/COLIBRÍ (FM-GFT) optical observations DATE: 25/07/07 19:33:31 GMT FROM: Benjamin Schneider at MIT <bschn(a)mit.edu> Sarah Antier (OCA), Kin Ocelotl López (UNAM), Alan M. Watson (UNAM), Benjamin Schneider (LAM), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Fredd Alvarez (UNAM), Jean-Luc Atteia (IRAP), Camila Angulo (UNAM), Dalya Akl (AUS), Rosa L. Becerra (U Roma), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Jean-Grégoire Ducoin (CPPM), Francis Fortin (IRAP), Leonardo García García (UNAM), Noémie Globus (UNAM), Diego López-Cámara (UNAM), Francesco Magnani (CPPM), Enrique Moreno Méndez (UNAM), Margarita Pereyra (UNAM), Ny Avo Rakotondrainibe (LAM), Antonio de Ugarte Postigo (LAM), J. X Cao (GXU) and Y.H Cheng (SWIFAR, YNU): We imaged the field of the SVOM GRB 250704A (Cao et al., GCN Circ. 40934) using the DDRAGO wide-field imager on the SVOM/COLIBRÍ (FM-GFT) telescope. We observed from 2025-07-05 10:03:36 to 10:45:54 UTC (from 1.26 to 1.29 days after the trigger) and obtained 32 minutes of exposure in the r filter. The data were reduced and coadded with the COLIBRÍ pipeline and analyzed with STDWeb/STDPipe (Karpov 2025). The photometry was calibrated using nearby stars from the PanSTARRS DR1 catalog, is in the AB system, and is not corrected for Galactic extinction. We detected the optical counterpart reported by Schneider et al., GCN Circ. 40953; Cao et al., GCN Circ 40964; and Siegel et al., GCN 40981 at a preliminary magnitude of: r = 22.05 +/- 0.09 Further observations are planned. 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/41017. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39066] EP250702a/GRB250702 B,D,E: GRANDMA Upper Limit
by GCN Circulars 07 Jul '25

07 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41016 SUBJECT: EP250702a/GRB250702 B,D,E: GRANDMA Upper Limit DATE: 25/07/07 19:18:12 GMT FROM: Dalya Akl at American Uni. SHJ <dalyaakl.d(a)gmail.com> D. Akl (AUS), K. Noysena, A. Manasanun (NARIT), M. Freeberg, R. Hellot (KNC), C. Andrade (UMN), W. Corradi (LNA), M. Pillas (Uliege), S. Antier (OCA/IJCLAB), N. Kochiashvili (AbAO), M. Lamoureux (UCLouvain), on behalf of GRANDMA: We observed the field of EP250702a (GCN 40906; associated with GRBs 250702/B/D/E) with GRANDMA and Kilonova Catcher and did not detect any optical counterpart. All our measurements can be downloaded from: [https://skyportal-icare.ijclab.in2p3.fr/public/sources/EP250702a/](https://… 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. Images obtained with the Johnson-Cousin filters were calibrated using the Gaia DR3 Synphot catalog. We use the SkyPortal application (skyportal.io) to monitor our observational campaign (Coughlin et al. 2023). Our observations are consistent with previously reported measurements (refer to SkyPortal for a subset of GCN measurements we collected). 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/41016. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39065] GRB 250706B: Swift/UVOT Detection
by GCN Circulars 07 Jul '25

07 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41015 SUBJECT: GRB 250706B: Swift/UVOT Detection DATE: 25/07/07 18:35:19 GMT FROM: Mike Siegel at PSU/Swift MOC <mhs18(a)psu.edu> M. H. Siegel (PSU) reports on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 250706B 12.5 ks after the SVOM/ECLAIRs trigger (Palmerio et al., GCN Circ. 40989). A source consistent with the XRT position (Ferro et al., GCN Circ. 40996) and the optical transient (Zhu et al., GCN Circ. 40991; Palmerio et al., GCN Circ. 40992; Romanov, GCN Circ. 40995) is detected in the UVOT exposures. The preliminary UVOT position is: RA (J2000) = 02:44:53.43 = 41.23097 (deg.) Dec (J2000) = -50:03:40.2 = -50.06116 (deg.) with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence). Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag u 12471 18805 2023 16.49+/-0.03 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.026 in the direction of the burst (Schlegel et al. 1998). View this GCN Circular online at https://gcn.nasa.gov/circulars/41015. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39064] EP250702a/ GRB 250702B: NuSTAR X-ray Observations
by GCN Circulars 07 Jul '25

07 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41014 SUBJECT: EP250702a/ GRB 250702B: NuSTAR X-ray Observations DATE: 25/07/07 17:46:46 GMT FROM: Brendan O'Connor at Carnegie Mellon University <boconno2(a)andrew.cmu.edu> Brendan O’Connor (CMU), Dheeraj Pasham (Eureka Scientific/George Washington), Igor Andreoni (UNC), Jeremy Hare (Catholic/GSFC) report on behalf of a larger collaboration: We observed the X-ray transient EP250702a (GCN 40906), which is also associated with the multiple gamma-ray triggers designated as GRB 250702B/D/E (GCNs 40883, 40886, 40890, 40891, 40931, 40903, 40914, 40923), with the NuSTAR X-ray Telescope through a Target of Opportunity observation through GO program 11282 (PI: Pasham). The observation occurred between 2025-07-03 20:45:21 and 2025-07-04 09:15:00 UTC for an on-source exposure of ~21.5 ks, simultaneous with Swift/XRT observations (ObsID: 19906002). The source is clearly detected at an average rate of ~0.4 cts/s. The 3-79 keV X-ray lightcurve shows short term variability throughout the full exposure in both FPMA and FPMB, but no flaring is observed. The source varies in count rate by a factor of 2-3 on timescales as short as a few ks. Compared to NuSTAR observations of GRB 221009A at a similar count rate (GCNs 32695, 32788), the source shows more significant variability, which we suggest disfavors an ultralong GRB origin, especially in conjunction with the July 1st onset reported by the Einstein Probe (GCN 40906). The X-ray spectra are featureless and do not show any Fe lines or reflection features. This is consistent with the lack of features in the Swift/XRT spectra. The 3-79 keV spectrum (FPMA+FPMB) is well fit by an absorbed powerlaw with a photon index of Gamma~1.81+/-0.03, which is consistent with the initial Swift/XRT spectral index within errors (GCN 40919). The hydrogen column density was fixed to 1e22 cm^-2 as per the best-fit Swift/XRT spectra (see https://www.swift.ac.uk/LSXPS/transients/9377) The unabsorbed 3-79 keV flux (time-averaged) is (2.35+/-0.05)e-11 erg/cm^2/s during our observation. We also performed a fit with an absorbed cutoff powerlaw and find a cutoff energy >60 keV. In this case, the best-fit photon index is Gamma~1.67+/-0.08. This has better agreement with the EP/FXT result, although the FXT observation was obtained at an earlier time (GCN 40917). The C-stat between both fits to the NuSTAR data was nearly identical and the cutoff powerlaw is not a statistically significant improvement. We suggest that the lack of Fe lines, and lack of cutoff in the powerlaw spectra (out to at least 60 keV), is atypical for an X-ray binary. We performed a Lomb-Scargle analysis on the barycenter corrected X-ray data, and did not identify any periodic signals over the frequency range 1e-3 to 100 Hz, consistent with the EP/FXT report (GCN 40917). The periodogram becomes red noise dominated below 3e-3 Hz. Further analysis is underway and additional NuSTAR and Swift observations are planned. We thank the NuSTAR SOC, and in particular Karl Forster and Brian Grefenstette, for promptly implementing these observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/41014. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39063] GRB 250706C: Konus-Wind detection of a very bright GRB ~1200 s before GRB 250706B
by GCN Circulars 07 Jul '25

07 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41013 SUBJECT: GRB 250706C: Konus-Wind detection of a very bright GRB ~1200 s before GRB 250706B DATE: 25/07/07 17:17:34 GMT FROM: Dmitry Frederiks at Ioffe Institute <fred(a)mail.ioffe.ru> D. Frederiks, A.Lysenko, A. Ridnaia, D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline, on behalf of the Konus-Wind team, report: The long-duration GRB 250706C triggered Konus-Wind (KW) at T0=60322.626 s UT (16:45:22.626). The burst light curve shows a very bright, multi-peaked emission pulse with the duration of ~50 s (20-1500 keV). This pulse is followed by a weaker, smoothly decaying emission tail, visible at lower energies (20-100 keV) up to the end of the KW triggered data record (~T0+250 s). A preliminary plot of the KW light curve is available at http://www.ioffe.ru/LEA/GRBs/GRB250706_T60322/KW20250706_60322_BG.png The KW ecliptic latitude response suggest the source location in the southern ecliptic hemisphere, at moderate-to-high ecliptic latitude. We note that the KW trigger time is ~1200 s before SVOM/ECLAIRs trigger on GRB 250706B at 2025-07-06T17:05:23 (Palmerio et al., GCN 40989), in the [5-20] keV energy band, and localized to R.A., Dec. 41.1337, -50.1172 deg, which is consistent with the KW ecliptic latitude response. This may suggest that the KW GRB 250706C is an initial, prompt emission episode of GRB 250706B. The KW analysis of GRB 250706C is ongoing and its detailed results will be reported in a separate GCN. View this GCN Circular online at https://gcn.nasa.gov/circulars/41013. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39062] GRB 250704A: Swift/BAT-GUANO localization skymap of a burst
by GCN Circulars 07 Jul '25

07 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41012 SUBJECT: GRB 250704A: Swift/BAT-GUANO localization skymap of a burst DATE: 25/07/07 16:55:49 GMT FROM: Jimmy DeLaunay at Penn State <delauj2(a)gmail.com> James DeLaunay (PSU), Samuele Ronchini (PSU), Aaron Tohuvavohu (Caltech), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC), Maia Williams (PSU) report: Swift/BAT did not localize GRB 250704A onboard (T0: 2025-07-04T03:42:20.17 UTC, SVOM trig sb25070404) 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 90 seconds of BAT event-mode data from [-45,+45] 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 12.0 in a 4.096 s analysis time bin, starting at T0. 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 9,536 deg2 and the 50% credible area is 2,278 deg2. The integrated probability inside the coded field of view is <1%. The NITRATES skymap is consistent with the SVOM/ECLAIRS position (GCN 40934), and the afterglow position (SVOM/VT GCN 40964, SVOM/MXT GCN 40934, Swift/XRT GCN 40950, Swift/UVOT GCN 40981, VLT/X-shooter GCN 40953) with the position lying on the ~0.01 credible region contour. A plot of the probability skymap can be viewed here: [skymap_plot](https://guano.swift.psu.edu/trigger_report?id=773293376/#:~:te… The probability skymap file can be downloaded from the link here [skymap_fits_file](https://guano.swift.psu.edu/files/773293376/0_n_PROBMAP) 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=773293376 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/41012. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39061] GRB 250702F: GRANDMA observations
by GCN Circulars 07 Jul '25

07 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41011 SUBJECT: GRB 250702F: GRANDMA observations DATE: 25/07/07 16:38:26 GMT FROM: Sarah Antier at OCA <sarah.antier(a)oca.eu> S. Antier (OCA/IJCLAB), S. Karpov (FZU), E. de Bruin (UMN), N. Kochiashivili (AbAO), M. Lamoureux (Uliege), T. Du Laz (Caltech), A. Klotz (IRAP), C. Limonta (OCA) on behalf of GRANDMA: We observed the field of GRB 250702F (Fermi GBM team, GCN 40892; Klingler et al., GCN 40894) with TAROT and Kilonova catcher (GCN 40969), 1.72 min post T0 and obtained optical counterpart detection. All our measurements are made public and can be downloaded in order to support the Swift and Fermi/GBM GRB science: https://skyportal-icare.ijclab.in2p3.fr/public/sources/GRB-250702_210643/ve… All the data have been reduced by a single data processing pipeline, STDPipe (Karpov et al., 2025). Images obtained with the sloan filters were calibrated using the PanSTARRS DR1 catalog. Images obtained with the Johnson-cousins filters were calibrated using the GAIA DR3 synphot catalog. We use the SkyPortal application (skyportal.io) to monitor our observational campaign (Coughlin et al. 2023). Our observations are consistent with other already reported (see the Skyportal page) Jelinek et al. (GCN 40895); Kumar et al. (GCN 40896); Lipunov et al. (GCN 40898); Martin-Carrillo et al. (GCN 40900); Angulo et al. (GCN 40907); Becerra et al. (GCN 40911); Brivio et al. (GCN 40913); An et al. (GCN 40916); Dutton et al. (GCN 40921); Odeh et al. (GCN 40925); Moretti et al. (GCN 40926); Siegel et al. (GCN 40933); Ma et al. (GCN 40936); Vinko et al. (GCN 40939); Mohan et al. (GCN 40946); Ciabattari et al. (GCN 40968). 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/) Skyportal/ICARE is supported by ACME. View this GCN Circular online at https://gcn.nasa.gov/circulars/41011. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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