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

[vsnet-grb-info 38771] sb25061207: Mephisto optical upper limits
by GCN Circulars 15 Jun '25

15 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40731 SUBJECT: sb25061207: Mephisto optical upper limits DATE: 25/06/15 03:55:24 GMT FROM: Brajesh Kumar at SWIFAR, YNU <brajesh(a)ynu.edu.cn> Ziwei Li, Guowang Du, Haipeng Lei, Jianhui Lian, Haoyang He, Xingzhu Zou, Yu Pan, Xinlei Chen, Xufeng Zhu, Helong Guo, Tao Wang, Yuan Fang, Jinghua Zhang, Dezi Liu, Chenxu Liu, Shiyan Zhong, Edoardo Lagioia, Brajesh Kumar, Yuanpei Yang, Xiangkun Liu, Xiaowei Liu (all SWIFAR, YNU) report on behalf of the Mephisto Team: We conducted simultaneous multi-band photometric observations of sb25061207 detected by SVOM/ECLAIRs (Zhang et al., GCN 40697) with the Multi-channel Photometric Survey Telescope (Mephisto) of Yunnan University, located at the Lijiang Observatory. Simultaneous u, g and v, r band observations of the field were initiated at 15:52:39 UTC on 2025-06-12 (~5.42 hours after the trigger) and three exposures of 300 seconds were acquired. In the stack images, no credible source was detected at the position of SVOM/VT (Li et al., GCN 40707), Swift/XRT (Evans et al., GCN 40711) and EP-FXT (Song et al., GCN 40718). The preliminary 3-sigma upper limits are listed below which are consistent with SVOM/COLIBRÍ (FM-GFT) (Becerra et. al., GCN 40723). | UT Start |T-T0 (hr)|Band| EXP(s) |Lim-mag (AB) |2025-06-12T15:52:39| 5.42 | u | 300.0*3 | >21.24 |2025-06-12T16:10:13| 5.71 | v | 300.0*3 | >21.31 |2025-06-12T15:52:38| 5.42 | g | 300.0*3 | >21.60 |2025-06-12T16:10:12| 5.71 | r | 300.0*3 | >21.83 ---------------------------------------------------------- Mephisto (Multi-channel Photometric Survey Telescope) is a 1.6-m wide-field multi-channel telescope, the first of its type in the world, capable of imaging the same field of view in three optical bands simultaneously. It provides real-time, high-quality colors of stellar objects. The on-site telescope assemblage and commissioning were carried out in September 2022. The first light in all three channels was achieved on 2023 December 21. ---------------------------------------------------------- View this GCN Circular online at https://gcn.nasa.gov/circulars/40731. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38770] IceCube alert 141029_8144692 retraction
by GCN Circulars 14 Jun '25

14 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40730 SUBJECT: IceCube alert 141029_8144692 retraction DATE: 25/06/14 15:31:50 GMT FROM: Erik Blaufuss at University of Maryland, College Park <blaufuss(a)umd.edu> The IceCube Collaboration (http://icecube.wisc.edu/) reports: On 14 June 2025 at 09:14:04 UT IceCube issued an alert (https://gcn.gsfc.nasa.gov/notices_amon_icecube_cascade/141029_8144692.amon) reporting the detection of a neutrino cascade candidate event with a high chance of being of astrophysical origin. Upon further examination by the IceCube collaboration, the event was found to be from a non-standard configuration that was intended to be excluded from alert selection At the time of this alert, the detector was operating normally but taking data in a non-standard test configuration. Normally, these periods of operation are excluded from generating alerts, but an alert message was significantly delayed in transit from the detector site at the South Pole and arrived after resuming normal operations We apologize for any confusion this error may have caused. The IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc(a)icecube.wisc.edu View this GCN Circular online at https://gcn.nasa.gov/circulars/40730. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38769] Fermi Gamma-ray Burst Monitor trigger 771596290/250614513 is not a GRB
by GCN Circulars 14 Jun '25

14 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40729 SUBJECT: Fermi Gamma-ray Burst Monitor trigger 771596290/250614513 is not a GRB DATE: 25/06/14 13:13:42 GMT FROM: Cuán de Barra at UCD <cuan.debarra(a)ucdconnect.ie> C.de Barra (University College Dublin) reports on behalf of the Fermi Gamma-ray Burst Monitor Team: "The Fermi Gamma-ray Burst Monitor (GBM) trigger 771596290/250614513 at 12:18:05.02 UT on 14 June 2025, tentatively classified as a GRB, is in fact not due to a GRB. This trigger is likely due to local particle activity." View this GCN Circular online at https://gcn.nasa.gov/circulars/40729. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38768] GRB 250614A: Fermi GBM Final Real-time Localization
by GCN Circulars 14 Jun '25

14 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40728 SUBJECT: GRB 250614A: Fermi GBM Final Real-time Localization DATE: 25/06/14 12:28:37 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 12:18:05 UT on 14 Jun 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250614A (trigger 771596290.023932 / 250614513). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 343.1, Dec = 54.6 (J2000 degrees, equivalent to J2000 22h 52m, 54d 36'), with a statistical uncertainty of 1.0 degrees. The angle from the Fermi LAT boresight is 1.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250614513/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250614513/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250614513/… View this GCN Circular online at https://gcn.nasa.gov/circulars/40728. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38767] EP250612a / GRB 250612B: NOT optical observations of the afterglow candidate
by GCN Circulars 14 Jun '25

14 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40727 SUBJECT: EP250612a / GRB 250612B: NOT optical observations of the afterglow candidate DATE: 25/06/14 08:29:34 GMT FROM: Antonio Martin-Carrillo at UCD,Space Science Group <antonio.martin-carrillo(a)ucd.ie> A. de Ugarte Postigo (LAM), A. Martin-Carrillo (UCD), G. Corcoran (UCD), D. B. Malesani (DAWN/NBI and Radboud), D. Xu (NAOC), L. Cotter (UCD), B. P. Gompertz (U. Birmingham), A. A. Djupvik (NOT), L. Fuglsang (NOT), report on behalf of a larger collaboration. We observed the field of EP250612a / GRB 250612B detected by EP (Hua et al., GCN 40700) and Fermi (Fermi GBM team, GCN 40702), using the ALFOSC camera mounted on the Nordic Optical Telescope (NOT). We obtained 12x100 s exposures in the SDSS r-band, starting at 23:19 UT on 2025-05-13 (1.952 days after the EP trigger). At J2000 coordinates RA:15:18:36.667, DEC: -26:46:03.624 (error 0.5”), consistent with those by Li et al. (GCN 40716), the optical counterpart is detected in our stacked image with a preliminary magnitude: r = 23.59 +/- 0.22 (AB). The photometric calibration was performed using nearby stars from the Pan-STARRS catalog and the magnitudes are not corrected for Galactic extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/40727. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38766] Fermi Gamma-ray Burst Monitor trigger 771547945/250613953 is not a GRB
by GCN Circulars 14 Jun '25

14 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40726 SUBJECT: Fermi Gamma-ray Burst Monitor trigger 771547945/250613953 is not a GRB DATE: 25/06/14 00:57:35 GMT FROM: sumanbala2210(a)gmail.com S. Bala (USRA) reports on behalf of the Fermi Gamma-ray Burst Monitor Team: "The Fermi Gamma-ray Burst Monitor (GBM) trigger 771547945/250613953 at 22:52:20.54 UT on 13 June 2025, tentatively classified as a GRB, is in fact not due to a GRB. This trigger is likely due to local particles." View this GCN Circular online at https://gcn.nasa.gov/circulars/40726. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38765] Fermi Gamma-ray Burst Monitor trigger 771541927/250613883 is not a GRB
by GCN Circulars 13 Jun '25

13 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40725 SUBJECT: Fermi Gamma-ray Burst Monitor trigger 771541927/250613883 is not a GRB DATE: 25/06/13 23:39:36 GMT FROM: sumanbala2210(a)gmail.com S. Bala (USRA) reports on behalf of the Fermi Gamma-ray Burst Monitor Team: "The Fermi Gamma-ray Burst Monitor (GBM) trigger 771541927/250613883 at 21:12:02.66 UT on 13 June 2025, tentatively classified as a GRB, is in fact not due to a GRB. This trigger is likely due to local particles. View this GCN Circular online at https://gcn.nasa.gov/circulars/40725. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38764] sb25061218: SVOM/COLIBRÍ (FM-GFT) optical upper limits
by GCN Circulars 13 Jun '25

13 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40724 SUBJECT: sb25061218: SVOM/COLIBRÍ (FM-GFT) optical upper limits DATE: 25/06/13 20:05:07 GMT FROM: Alan Watson at UNAM <alan(a)astro.unam.mx> Alan M. Watson (UNAM), Rosa L. Becerra (U Roma), Enrique Moreno Méndez (UNAM), Sarah Antier (OCA), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Fredd Alvarez (UNAM), Jean-Luc Atteia (IRAP), Camila Angulo (UNAM), Dalya Akl (AUS), Nathaniel R. Butler (ASU) , Damien Dornic (CPPM), Jean-Grégoire Ducoin (CPPM), Francis Fortin (IRAP), Noémie Globus (UNAM), Kin Ocelotl López (UNAM), Diego López-Cámara (UNAM), Francesco Magnani (CPPM), Margarita Pereyra (UNAM), Ny Avo Rakotondrainibe (LAM), Benjamin Schneider (LAM), Antonio de Ugarte Postigo (LAM), and Jerome Rodriguez (CEA): We imaged the field of the SVOM X-ray transient sb25061218 (Rodriguez et al., GCN 40712) using the DDRAGO wide-field imager on the SVOM/COLIBRÍ (FM-GFT) telescope. We observed from 2025-06-13 06:18 to 10:34 UTC (from 9.7 to 14.0 hours after the trigger) and obtained 112 minutes of exposure in the i 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 Pan-STARRS DR1 catalog, is on the AB scale, and is not corrected for Galactic extinction. In the stacked image, we do not detect any new source within the ECLAIRs source region reported by Rodriguez et al. (GCN 40712) to a formal 10-sigma limit of: i > 23.0, although we note that this is roughly the 50% completion limit of the Pan-STARRS DR1 catalog used to identify new sources. We also performed image subtraction against Pan-STARRS DR2 at the position of the two XRT sources 1 and 2 reported by Evans et al. (GCN Circ. 40721) and see no evidence for optical counterparts to the same limit. 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/40724. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38763] sb25061207: SVOM/COLIBRÍ (FM-GFT) optical upper limit
by GCN Circulars 13 Jun '25

13 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40723 SUBJECT: sb25061207: SVOM/COLIBRÍ (FM-GFT) optical upper limit DATE: 25/06/13 19:16:15 GMT FROM: Rosa L. Becerra at Tor Vergata, Roma <rosa.becerra(a)roma2.infn.it> Rosa L. Becerra (U Roma), Alan M. Watson (UNAM), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Fredd Alvarez (UNAM), Jean-Luc Atteia (IRAP), Camila Angulo (UNAM), Dalya Akl (AUS), Sarah Antier (OCA), 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), Margarita Pereyra (UNAM), Ny Avo Rakotondrainibe (LAM), Benjamin Schneider (LAM), Antonio de Ugarte Postigo (LAM), L. Zhang (IHEP), and Y. D. Hu (GXU): We imaged the field of the SVOM/ECLAIR sb25061207 (Zhang et al., GCN Circ. 40697) using the DDRAGO wide-field imager on the SVOM/COLIBRÍ (FM-GFT) telescope. We observed from 2025-06-13 03:49 to 05:52 UTC (from 17.36 to 19.41 hours after the trigger) and obtained 63 minutes of exposure in the r filter. 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. In the stacked image, we do not detect any new source at the EP/FXT position (Song et al., GCN Circ. 40718) or the optical candidate by SVOM/VT (Li et al. GCN Circ. 40717) down to the following 3-sigma limit: r > 22.9 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/40723. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38762] Fermi trigger No 771494087: Global MASTER-Net observations report
by GCN Circulars 13 Jun '25

13 Jun '25

TITLE: GCN CIRCULAR NUMBER: 40722 SUBJECT: Fermi trigger No 771494087: Global MASTER-Net observations report DATE: 25/06/13 18:16:25 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 GRB250613.33 (trigger No 771494087,17h 33m 19.92s , -38d 28m 01.2s, R=22.7) errorbox 32096 sec after notice time and 32128 sec after trigger time at 2025-06-13 16:50:10 UT, with upper limit up to 17.9 mag. Observations started at twilight. The observations began at zenith distance = 60 deg. The sun altitude is -14.4 deg. The galactic latitude b = -3 deg., longitude l = 351 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2901954 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 32158 | 2025-06-13 16:50:10 | MASTER-SAAO | (16h 41m 27.50s , -39d 04m 53.5s) | C | 60 | 17.8 | 32158 | 2025-06-13 16:50:10 | MASTER-SAAO | (16h 39m 08.66s , -38d 49m 46.2s) | C | 60 | 17.8 | 32346 | 2025-06-13 16:53:18 | MASTER-SAAO | (16h 41m 29.84s , -39d 04m 40.2s) | C | 60 | 17.9 | 32346 | 2025-06-13 16:53:18 | MASTER-SAAO | (16h 39m 10.94s , -38d 49m 34.3s) | C | 60 | 17.9 | 32992 | 2025-06-13 17:04:04 | MASTER-SAAO | (16h 41m 23.49s , -39d 06m 43.4s) | C | 60 | 17.8 | 32992 | 2025-06-13 17:04:04 | MASTER-SAAO | (16h 39m 05.20s , -38d 51m 34.7s) | C | 60 | 17.8 | 33181 | 2025-06-13 17:07:13 | MASTER-SAAO | (16h 41m 25.91s , -39d 05m 03.0s) | C | 60 | 17.9 | 33181 | 2025-06-13 17:07:13 | MASTER-SAAO | (16h 39m 07.41s , -38d 49m 54.4s) | C | 60 | 17.9 | 33369 | 2025-06-13 17:10:21 | MASTER-SAAO | (16h 41m 29.24s , -39d 04m 53.3s) | C | 60 | 17.8 | 33369 | 2025-06-13 17:10:21 | MASTER-SAAO | (16h 39m 10.68s , -38d 49m 45.2s) | C | 60 | 17.8 | 33558 | 2025-06-13 17:13:30 | MASTER-SAAO | (16h 41m 22.46s , -39d 04m 40.0s) | C | 60 | 17.8 | 33558 | 2025-06-13 17:13:30 | MASTER-SAAO | (16h 39m 03.78s , -38d 49m 32.6s) | C | 60 | 17.8 | 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/40722. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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