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

[vsnet-grb-info 38957] GRB 250702F: DDOTI Optical Observation
by GCN Circulars 03 Jul '25

03 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40911 SUBJECT: GRB 250702F: DDOTI Optical Observation DATE: 25/07/03 10:35:15 GMT FROM: Rosa L. Becerra at Tor Vergata, Roma <rosa.becerra(a)roma2.infn.it> Rosa L. Becerra (U Roma), Alan M. Watson (UNAM), Sahil Atri (U Roma), Camila Angulo Valdez (UNAM), Nat Butler (ASU), Simone Dichiara (Penn State University), Tsvetelina Dimitrova (ASU), Alexander Kutyrev (GSFC/UMD), William H. Lee (UNAM), Océlotl López (UNAM), Margarita Pereyra (UNAM) and Eleonora Troja (U Roma) report: We observed the field of GRB 250702F detected by Swift (Klingler et al., GCN Circ. 40894) and Fermi/GBM (Fermi GBM Team, GCN Circ. 40892) with the DDOTI/OAN wide-field imager at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir (http://ddoti.astroscu.unam.mx) on the night of 2025-07-03 UTC. DDOTI observed the Swift/UVOT position (Klingler et al., GCN Circ. 40894) from 04:12 UTC to 08:31 UTC (from T+7.1 h to T+ 11.4 h after the trigger), obtaining a total exposure of 2.4 hours, alternating with other scientific programs. Comparing our observations to Pan-STARRS PS1 DR2 catalogues, we detect the optical counterpart reported by Klingler et al. (GCN Circ. 40894), Jelinek et al. (GCN Circ. 40895), Kumar et al. (GCN Circ. 40896), Lipunov et al. (GCN Circ. 40899), Martin-Carrillo et al. (GCN Circ. 40900), de Ugarte Postigo et al. (GCN Circ. 40901) and Angulo et al. (GCN Circ. 40907) with an AB magnitude of: w = 19.85 +/- 0.05 This value is not corrected for the Galactic extinction. We thank the staff of the Observatorio Astronómico Nacional on the Sierra of San Pedro Mártir. View this GCN Circular online at https://gcn.nasa.gov/circulars/40911. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38956] MAXI/GSC detection of an X-ray activity from a transient associated with GRB 250702B,C,D,E and EP250702a
by GCN Circulars 03 Jul '25

03 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40910 SUBJECT: MAXI/GSC detection of an X-ray activity from a transient associated with GRB 250702B,C,D,E and EP250702a DATE: 25/07/03 09:47:38 GMT FROM: Yuta Kawakubo at Aoyama Gakuin University <kawakubo(a)phys.aoyama.ac.jp> Y. Kawakubo, M. Serino (AGU), H. Negoro, M. Nakajima, , K. Takagi, H. Takahashi, K. Tatano, H. Nishio (Nihon U.), T. Mihara, T. Tamagawa, N. Kawai, M. Matsuoka (RIKEN), T. Sakamoto, S. Sugita, H. Hiramatsu, Y. Kondo, A. Yoshida (AGU), Y. Tsuboi, H. Sugai, N. Nagashima (Chuo U.), M. Shidatsu, Y. Niida, C. Kang, T. Nakamoto (Ehime U.), I. Takahashi, Y. Yatsu (Science Tokyo), S. Nakahira, S. Ueno, H. Tomida, M. Ishikawa, S. Ogawa, M. Kurihara (JAXA), Y. Ueda, K. Fujiwara (Kyoto U.), M. Yamauchi, M. Nishio, C. Hiraizumi (Miyazaki U.), K. Yamaoka (Nagoya U.), M. Sugizaki (Kanazawa U.), W. Iwakiri (Chiba U.), T. Kawamuro (Osaka U.), S. Yamada (Tohoku U) We report on the MAXI/GSC detection of an X-ray transient source on July 2, 2025 (MJD 60858) associated with GRB 250702B,C,D,E/EP250702a. The source was clearly detected at three scan transits from 2025-07-02T12:59 UT to 2025-07-02T16:15. Assuming that the source flux was constant over the three transits, we obtain the source position at (284.462 deg, -7.936 deg) = (18 57 50, -07 56 09) (J2000) with a statistical 90% C.L. elliptical error region with long and short radii of 0.34 deg and 0.24 deg, respectively. The roll angle of the long axis from the north direction is 54.0 deg counterclockwise. There is an additional systematic uncertainty of 0.1 deg (90% containment radius). The X-ray flux averaged over the three scans was 54 +- 11 mCrab. The time and the source position determined by the MAXI observations are consistent with GRB 250702B, C, D, E, observed by Fermi-GBM (GCN 40883, 40885, 40886, 40890, 40891), the source localization skymap provided by Swift/BAT-GUANO (GCN 40903) and EP250702a observed by the Einstein Probe/WXT, FXT (GCN 40906). Follow-up observations are encouraged. View this GCN Circular online at https://gcn.nasa.gov/circulars/40910. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38955] GRB 250703A: Fermi GBM Final Real-time Localization
by GCN Circulars 03 Jul '25

03 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40909 SUBJECT: GRB 250703A: Fermi GBM Final Real-time Localization DATE: 25/07/03 09:28:11 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 09:07:31 UT on 3 Jul 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250703A (trigger 773226456.426922 / 250703380). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 337.6, Dec = 26.1 (J2000 degrees, equivalent to J2000 22h 30m, 26d 06'), with a statistical uncertainty of 1.2 degrees. The angle from the Fermi LAT boresight is 131.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250703380/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250703380/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250703380/… View this GCN Circular online at https://gcn.nasa.gov/circulars/40909. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38954] EP250702a/GRB 250702B,C,D,E: GOTO optical upper limits
by GCN Circulars 03 Jul '25

03 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40908 SUBJECT: EP250702a/GRB 250702B,C,D,E: GOTO optical upper limits DATE: 25/07/03 07:38:27 GMT FROM: Amit Kumar at Royal Holloway - UoL/ U of Warwick, UK <amitkundu515(a)gmail.com> A. Kumar, B. P. Gompertz, G. Ramsay, R. Starling, K. Ackley, M. J. Dyer, J. Lyman, K. Ulaczyk, D. O'Neill, B. Godson, D. Steeghs, D. K. Galloway, V. Dhillon, P. O'Brien, K. Noysena, R. Kotak, R. P. Breton, L. K. Nuttall, and J. Casares report on behalf of the GOTO collaboration: We report on observations with the Gravitational-wave Optical Transient Observer (GOTO; Steeghs et al. 2022, Dyer et al. 2024) in response to GRB 250702B, C, D and E (Fermi GBM Team, GCNs 40883, 40885, 40886, 40890 and 40891). Targeted observations were performed between 2025-07-02 23:16:56 UT and 2025-07-03 02:52:31 UT (between 20.39 and 23.98 hours after trigger). Each observation consisted of 4x90s exposures in the GOTO L-band (400-700 nm). Images were processed immediately after acquisition using the GOTO pipeline. Difference imaging was performed using deeper template observations of the same pointings. Source candidates were initially filtered using a classifier (Killestein et al. 2021) and cross-matched against a variety of contextual and minor planet catalogues. Human vetting was carried out in real time on any candidates that passed the above checks. We identify no candidate optical counterparts within the EP/FXT (Cheng et al. 40906) 90% localisation region with typical 3-sigma limits ranging between L > 19.85 to L > 20.35 (AB). The deepest of these was taken at a mid-time of 2025-07-03 02:06:10 UT (23.21 hours after trigger). Magnitudes were calibrated using ATLAS-REFCAT2 (Tonry et al. 2018) and are not corrected for Galactic extinction. (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/40908. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38953] GRB 250702F: COLIBRÍ Observations of the Afterglow
by GCN Circulars 03 Jul '25

03 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40907 SUBJECT: GRB 250702F: COLIBRÍ Observations of the Afterglow DATE: 25/07/03 05:31:22 GMT FROM: Margarita Pereyra Talamantes at IA-UNAM Ensenada <mpereyra(a)astro.unam.mx> Camila Angulo (UNAM), Margarita Pereyra (UNAM), Alan M. Watson (UNAM), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Jean-Luc Atteia (IRAP), Fredd Alvarez (UNAM), Dalya Akl (AUS), Sarah Antier (OCA), Rosa L. Becerra (U Roma), Nathaniel R. Butler (ASU) , Damien Dornic (CPPM), Jean-Grégoire Ducoin (CPPM), Francis Fortin (IRAP), Leonardo García García (UNAM), Ramandeep Gill (UNAM), Noémie Globus (UNAM), Kin Ocelotl López (UNAM), Diego López-Cámara (UNAM), Francesco Magnani (CPPM), Enrique Moreno Méndez (UNAM), N. A. Rakotondrainibe (LAM), Benjamin Schneider (LAM) and Antonio de Ugarte Postigo (LAM): We imaged the field of the Swift GRB 250702F (Klingler et al., GCN Circ. 40894) using the DDRAGO wide-field imager on the COLIBRÍ telescope. We observed from 2025-07-03 03:53 to 04:03 UTC (from 6.78 to 6.95 hours after the trigger) and obtained 180 seconds of exposure in each of the g, r, and i filters. The data were reduced and coadded with the COLIBRÍ pipeline and analysed 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 Klingler et al. (GCN Circ. 40894), Jelinek et al. (GCN Circ. 40895), Kumar et al. (GCN Circ. 40896), Lipunov et al (GCN Circ. 40899), Martin-Carrillo et al. (GCN Circ. 40900), and de Ugarte Postigo et al (GCN Circ. 40901) at a preliminary magnitude of: g = 19.60 +/- 0.03 r = 19.52 +/- 0.03 i = 19.24 +/- 0.03 Further observations are ongoing. 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/40907. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38952] EP250702a : an X-ray transient detected by Einstein Probe likely associated with GRB 250702B,C,D,E
by GCN Circulars 03 Jul '25

03 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40906 SUBJECT: EP250702a : an X-ray transient detected by Einstein Probe likely associated with GRB 250702B,C,D,E DATE: 25/07/03 04:20:00 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> H. Q. Cheng (NAO, CAS), G. Y. Zhao (SYSU), C. Zhou (HUST), Y. H. Cheng (SWIFAR, YNU), Y. J. Zhang (THU), J. W. Hu, H. Sun and Z. X. Ling (NAO, CAS) on behalf of the Einstein Probe (EP) team: We report on the detection of an X-ray transient by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission, designated EP250702a. The source was first detected in an observation starting at 2025-07-02T02:53:44 (UTC), and was continuously detected in subsequent observations spanning from 2025-07-02T05:57:06 to 2025-07-02T22:32:44. The WXT position of the source is R.A. = 284.700 deg, DEC = -7.869 deg (J2000) with an uncertainty of 2.4 arcmin in radius (90% C.L. statistical and systematic). The source reached a peak flux in the observation starting at 2025-07-02T16:10:11 with an exposure of 827s, the epoch of which is generally consistent with the burst time of GRB 250702E (GCN 40890). Considering that EP250702a is spatially and temporally coincident with the GRB 250702B,C,D,E detected by Fermi /GBM (GCN 40883, 40885, 40886, 40890, 40891), we suggest that EP250702a is likely the X-ray source associated with GRB 250702B,C,D,E. The WXT position is also consistent with the source localization skymap provided by the Swift/BAT-GUANO (GCN 40903). Stacking of the WXT data taken prior to the WXT detection indicated that the source has already emerged on July 1st, 2025. The WXT spectrum of the peak flux epoch can be fitted with an absorbed power-law model (with the column density fixed at the Galactic absorption value of 5e21 cm^-2), yielding a photon index of 0.2+/-0.1 and an unabsorbed 0.5-4 keV flux of (5.5+/-0.7)e-10 ergs/s/cm^2. A follow-up observation with the Follow-up X-ray Telescope (FXT) onboard EP was performed but the telemetry data is still not available yet. The FXT onboard source detection algorithm gives an improved source position at R.A. = 284.6911 deg, DEC = -7.8715 deg (J2000) with an uncertainty of 20 arcsecond in radius (90% C.L. statistical and systematic). More information will be updated when the telemetry data is received. Launched on January 9, 2024, EP is a space X-ray observatory to monitor the soft X-ray sky with X-ray follow-up capability (Yuan et al. 2022, Handbook of X-ray and Gamma-ray Astrophysics) View this GCN Circular online at https://gcn.nasa.gov/circulars/40906. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38951] Fermi GRB 250702E: Global MASTER-Net observations report
by GCN Circulars 03 Jul '25

03 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40905 SUBJECT: Fermi GRB 250702E: Global MASTER-Net observations report DATE: 25/07/03 02:15:35 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 250702E ( Fermi GBM team, GCN 40890) errorbox 28126 sec after notice time and 28161 sec after trigger time at 2025-07-03 00:10:54 UT, with upper limit up to 18.6 mag. The observations began at zenith distance = 28 deg. The sun altitude is -68.5 deg. The galactic latitude b = -12 deg., longitude l = 19 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2923298 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 28191 | 2025-07-03 00:10:54 | MASTER-SAAO | (18h 58m 11.78s , -10d 24m 39.1s) | C | 60 | 18.2 | 28289 | 2025-07-03 00:12:31 | MASTER-SAAO | (19h 06m 18.96s , -10d 26m 55.8s) | C | 60 | 18.6 | 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/40905. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38950] Fermi GRB 250702B: Global MASTER-Net observations report
by GCN Circulars 03 Jul '25

03 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40904 SUBJECT: Fermi GRB 250702B: Global MASTER-Net observations report DATE: 25/07/03 02:15:23 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 250702B ( Fermi GBM team, GCN 40883) errorbox 36852 sec after notice time and 36888 sec after trigger time at 2025-07-03 00:10:54 UT, with upper limit up to 18.6 mag. The observations began at zenith distance = 28 deg. The sun altitude is -68.5 deg. The galactic latitude b = -7 deg., longitude l = 27 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2923151 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 36919 | 2025-07-03 00:10:54 | MASTER-SAAO | (18h 58m 11.78s , -10d 24m 39.1s) | C | 60 | 18.2 | 37016 | 2025-07-03 00:12:31 | MASTER-SAAO | (19h 06m 18.96s , -10d 26m 55.8s) | C | 60 | 18.6 | 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/40904. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38949] GRB 250702D, C, E: Swift/BAT-GUANO localization skymap of a burst or galactic transient
by GCN Circulars 03 Jul '25

03 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40903 SUBJECT: GRB 250702D, C, E: Swift/BAT-GUANO localization skymap of a burst or galactic transient DATE: 25/07/03 01:29:21 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: Fermi/GBM triggered on four possible GRBs with similar localizations (GCN 40891) that may all have a common origin. Three of these bursts (GRB 250702D GCN 40886, GRB 250702C GCN 40885, GRB 250702E GCN 40890) have been detected in Swift/BAT-GUANO data. GRB 250702D (T0: 2025-07-02T13:09:02.03 UTC, Fermi/GBM trig 773154547) was detected by the NITRATES analysis (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169) with a sqrt(TS) of 14.6 in a 8.192 s analysis time bin, starting at T0 - 6.144 s. The localization resulted in a 90% credible area of 5,318 deg2, a 50% credible area of 1,192 deg2, and an integrated probability of 5% inside the coded field of view. GRB 250702C (T0: 2025-07-02T14:49:31.91 UTC, Fermi/GBM trig 773160576) was detected by the NITRATES analysis with a sqrt(TS) of 7.5 in a 16.384 s analysis time bin, starting at T0 - 4.096 s. The localization resulted in a 90% credible area of 13,685 deg2, a 50% credible area of 4,087 deg2, and an integrated probability of 7% inside the coded field of view. GRB 250702E (T0: 2025-07-02T16:21:33.07 UTC, Fermi/GBM trig 773166098) was detected by the NITRATES analysis with a sqrt(TS) of 12.3 in a 8.192 s analysis time bin, starting at T0 - 4.096 s. The localization resulted in a 90% credible area of 8,604 deg2, a 50% credible area of 2,099 deg2, and an integrated probability of 3% inside the coded field of view. The localizations of all three bursts are consistent with the combined GBM skymap (GCN 40891). When the three NITRATES localizations are combined with the combined GBM skymap there is a slight improvement, with a 90% credible region of 142 deg2 centered at, RA, Dec = 285.820, -4.182 deg More details about these bursts and their skymaps can be found here: GRB 250702D https://guano.swift.psu.edu/trigger_report?id=773154577 GRB 250702C https://guano.swift.psu.edu/trigger_report?id=773160607 GRB 250702E https://guano.swift.psu.edu/trigger_report?id=773166128 The combined NITRATES and Fermi GBM skymap localization can be found here: https://zenodo.org/records/15795079 Additionally, imaging was performed to search for persistent emission while the source was in the coded field of view from ~13:28 to 13:48 UTC and from ~17:50 to 18:06 UTC, but nothing significant was found. 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/40903. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38948] GRB 250702F: Enhanced Swift-XRT position
by GCN Circulars 03 Jul '25

03 Jul '25

TITLE: GCN CIRCULAR NUMBER: 40902 SUBJECT: GRB 250702F: Enhanced Swift-XRT position DATE: 25/07/03 00:08:06 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team. Using 2088 s of XRT Photon Counting mode data and 2 UVOT images for GRB 250702F, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 212.93584, +16.74909 which is equivalent to: RA (J2000): 14h 11m 44.60s Dec (J2000): +16d 44' 56.7" with an uncertainty of 2.2 arcsec (radius, 90% confidence). This position may be improved as more data are received. The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177). This circular was automatically generated, and is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/40902. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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