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

[vsnet-grb-info 39120] Fermi GRB 250711A: Global MASTER-Net observations report
by GCN Circulars 11 Jul '25

11 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41068 SUBJECT: Fermi GRB 250711A: Global MASTER-Net observations report DATE: 25/07/11 20:30:49 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-Kislovodsk robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB 250711A ( Fermi GBM team, GCN 41064) errorbox 16346 sec after notice time and 16354 sec after trigger time at 2025-07-11 19:12:47 UT, with upper limit up to 14.3 mag. The observations began at zenith distance = 3 deg. The sun altitude is -19.0 deg. The galactic latitude b = 33 deg., longitude l = 71 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2932393 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 16384 | 2025-07-11 19:12:47 | MASTER-Kislovodsk | (17h 35m 16.38s , +45d 13m 31.4s) | C | 60 | 14.3 | 16560 | 2025-07-11 19:15:42 | MASTER-Kislovodsk | (17h 23m 53.68s , +45d 14m 28.9s) | C | 60 | 14.1 | 16814 | 2025-07-11 19:19:57 | MASTER-Kislovodsk | (17h 27m 35.59s , +47d 07m 43.8s) | C | 60 | 14.1 | 16990 | 2025-07-11 19:22:53 | MASTER-Kislovodsk | (17h 35m 19.19s , +45d 13m 39.0s) | C | 60 | 14.3 | 17157 | 2025-07-11 19:25:39 | MASTER-Kislovodsk | (17h 25m 01.99s , +45d 04m 21.7s) | C | 60 | 14.1 | 17316 | 2025-07-11 19:28:19 | MASTER-Kislovodsk | (17h 12m 47.71s , +43d 09m 45.1s) | C | 60 | 13.8 | 17396 | 2025-07-11 19:29:38 | MASTER-Kislovodsk | (17h 23m 53.71s , +43d 09m 27.0s) | C | 60 | 14.0 | 17475 | 2025-07-11 19:30:58 | MASTER-Kislovodsk | (17h 16m 58.46s , +46d 58m 51.1s) | C | 60 | 14.0 | 17555 | 2025-07-11 19:32:17 | MASTER-Kislovodsk | (17h 28m 41.84s , +46d 57m 30.3s) | C | 60 | 14.3 | 17725 | 2025-07-11 19:35:07 | MASTER-Kislovodsk | (17h 14m 53.39s , +45d 04m 13.4s) | C | 60 | 14.2 | 17804 | 2025-07-11 19:36:27 | MASTER-Kislovodsk | (17h 24m 56.77s , +45d 02m 55.6s) | C | 60 | 13.9 | 17883 | 2025-07-11 19:37:46 | MASTER-Kislovodsk | (17h 33m 42.38s , +43d 11m 07.6s) | C | 60 | 14.1 | 18042 | 2025-07-11 19:40:25 | MASTER-Kislovodsk | (17h 12m 51.25s , +43d 11m 29.3s) | C | 60 | 13.5 | 18122 | 2025-07-11 19:41:44 | MASTER-Kislovodsk | (17h 23m 46.84s , +43d 10m 09.4s) | C | 60 | 14.1 | 18201 | 2025-07-11 19:43:04 | MASTER-Kislovodsk | (17h 16m 53.40s , +46d 58m 56.6s) | C | 60 | 14.1 | 18281 | 2025-07-11 19:44:23 | MASTER-Kislovodsk | (17h 28m 41.67s , +46d 58m 00.4s) | C | 60 | 14.1 | 19103 | 2025-07-11 19:58:05 | MASTER-Kislovodsk | (17h 14m 39.74s , +45d 06m 31.7s) | C | 60 | 14.2 | 19183 | 2025-07-11 19:59:25 | MASTER-Kislovodsk | (17h 24m 52.80s , +45d 05m 05.2s) | C | 60 | 14.2 | 19262 | 2025-07-11 20:00:45 | MASTER-Kislovodsk | (17h 33m 37.59s , +43d 12m 30.2s) | C | 60 | 14.3 | 19421 | 2025-07-11 20:03:23 | MASTER-Kislovodsk | (17h 12m 39.43s , +43d 12m 29.1s) | C | 60 | 14.1 | 19500 | 2025-07-11 20:04:43 | MASTER-Kislovodsk | (17h 23m 43.29s , +43d 11m 35.5s) | C | 60 | 14.1 | 19580 | 2025-07-11 20:06:03 | MASTER-Kislovodsk | (17h 16m 41.83s , +46d 58m 18.5s) | C | 60 | 14.1 | 19660 | 2025-07-11 20:07:22 | MASTER-Kislovodsk | (17h 28m 32.18s , +46d 58m 57.2s) | C | 60 | 14.0 | 19739 | 2025-07-11 20:08:42 | MASTER-Kislovodsk | (17h 36m 11.71s , +45d 06m 17.3s) | C | 60 | 14.1 | 20058 | 2025-07-11 20:14:00 | MASTER-Kislovodsk | (17h 33m 29.49s , +43d 12m 34.0s) | C | 60 | 14.1 | 20217 | 2025-07-11 20:16:39 | MASTER-Kislovodsk | (17h 12m 38.24s , +43d 10m 13.3s) | C | 60 | 13.8 | 20296 | 2025-07-11 20:17:59 | MASTER-Kislovodsk | (17h 23m 42.07s , +43d 10m 47.1s) | C | 60 | 14.2 | 20376 | 2025-07-11 20:19:18 | MASTER-Kislovodsk | (17h 16m 42.38s , +47d 00m 04.9s) | C | 60 | 13.8 | 20455 | 2025-07-11 20:20:38 | MASTER-Kislovodsk | (17h 28m 26.32s , +46d 58m 17.9s) | C | 60 | 14.1 | 20535 | 2025-07-11 20:21:57 | MASTER-Kislovodsk | (17h 36m 11.04s , +45d 06m 15.9s) | C | 60 | 14.1 | 20694 | 2025-07-11 20:24:36 | MASTER-Kislovodsk | (17h 14m 31.90s , +45d 06m 29.8s) | C | 60 | 13.8 | 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/41068. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39119] EP250702a: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes
by GCN Circulars 11 Jul '25

11 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41067 SUBJECT: EP250702a: gamma-ray upper limits from joint observations by the LST-1 and MAGIC telescopes DATE: 25/07/11 17:01:56 GMT FROM: David Paneque at Max Planck Institute for Physics <dpaneque(a)mppmu.mpg.de> D. Paneque (MPP Munich), M. Teshima (MPP Munich), Arnau Aguasca-Cabot (UB, ICCUB, and IEEC-UB), Alessio Berti (MPP Munich), Sweta Menon (UNIROMA2 & INAF), Edna Ruiz-Velasco (LAPP Annecy), Monica Seglar-Arroyo (IFAE Barcelona) and Andrea Simongini (UNIROMA2 & INAF), on behalf of the CTAO-LST and MAGIC Collaborations report: We observed the field of EP250702a / GRBs 250702B,D,E (GCN 40883, 40886, 40890, 40891, 40906). A total of 2.94 hours of observations were conducted with the MAGIC telescopes, beginning at 2025-07-04 01:25:53 UTC. The final 1.79 hours of this period were carried out jointly with LST-1. A preliminary offline analysis of the LST-1 and MAGIC dataset shows no excess of gamma rays above 200 GeV in the field of EP250702a (GCN 40906). These results have been obtained using the LST analysis software, lst-chain (LST Collaboration, 2023 ApJ 956 80, v0.10.7), and the MAGIC analysis software MARS (Zanin et al. 2013, v 3.2.1). Observations were affected by reduced atmospheric transparency. A more in-depth analysis of this data set is ongoing. Subsequent observations are planned after the moonbreak, subject to the nature of upcoming detections. LST-1 is a prototype of the Large-Sized Telescope (LST) for the Cherenkov Telescope Array Observatory, and is located on the Canary island of La Palma, Spain. The telescope design is optimized for observation of gamma rays in the range from 20 GeV to 3 TeV. MAGIC is a system of two 17m-diameter Imaging Atmospheric Cherenkov Telescopes located on the Canary island of La Palma, Spain, and designed to perform gamma-ray astronomy in the energy range from 50 GeV to greater than 50 TeV. View this GCN Circular online at https://gcn.nasa.gov/circulars/41067. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39118] GRB 250704A: GRANDMA observations
by GCN Circulars 11 Jul '25

11 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41066 SUBJECT: GRB 250704A: GRANDMA observations DATE: 25/07/11 16:12:40 GMT FROM: Sarah Antier at OCA <sarah.antier(a)oca.eu> A. Manasanun, K. Noysena (NARIT), R. Hellot (KNC), S. Antier (OCA/IJCLAB), D. Akl (AUS), N. Kochiashivili (AbAO), T. Du Laz (Caltech), A. Klotz (IRAP), C. Limonta (OCA), M. Masek (FZU), M. Lamoureux (UCLouvain) on behalf of GRANDMA: We observed the field of SVOM GRB 250704A (Cao et al., GCN Circ. 40934) with TAROT, TRT and Kilonova catcher. All our measurements are made public and can be downloaded from: https://skyportal-icare.ijclab.in2p3.fr/public/sources/GCN-250704_034220/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-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 (see the Skyportal page), such as Schneider et al., GCN Circ. 40953; Cao et al., GCN Circ 40964; and Siegel et al., GCN 40981. 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/41066. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39117] GRB 250711A: BALROG localization (Fermi Trigger 773937617 / GRB 250711611)
by GCN Circulars 11 Jul '25

11 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41065 SUBJECT: GRB 250711A: BALROG localization (Fermi Trigger 773937617 / GRB 250711611) DATE: 25/07/11 15:08:21 GMT FROM: Jochen Greiner at MPE <jcgrog(a)mpe.mpg.de> T. Preis (University of Innsbruck) & J. Greiner (MPE Garching) report: The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger 773937617 at 14:40:12 on 11 July 2025 were automatically fitted for spectrum and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427; Berlato et al. 2019, ApJ 873, 60). The best-fit position is: RA(2000.0) = 267.8 deg Decl.(2000.0) = 35.9 deg The 1 sigma statistical error radius is 2.1 deg. We estimate an additional systematic error of 1 deg. Further details are available at: https://grb.mpe.mpg.de/grb/GRB250711611/ The Healpix map can be downloaded from: https://grb.mpe.mpg.de/grb/GRB250711611/healpix The location parameters are available as JSON at: https://grb.mpe.mpg.de/grb/GRB250711611/json View this GCN Circular online at https://gcn.nasa.gov/circulars/41065. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39116] GRB 250711A: Fermi GBM Final Real-time Localization
by GCN Circulars 11 Jul '25

11 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41064 SUBJECT: GRB 250711A: Fermi GBM Final Real-time Localization DATE: 25/07/11 14:50:44 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 14:40:12 UT on 11 Jul 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250711A (trigger 773937617.940244 / 250711611). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 261.2, Dec = 44.9 (J2000 degrees, equivalent to J2000 17h 24m, 44d 53'), with a statistical uncertainty of 1.2 degrees. The angle from the Fermi LAT boresight is 28.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250711611/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250711611/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250711611/… View this GCN Circular online at https://gcn.nasa.gov/circulars/41064. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39115] GRB 250704A: SVOM/ECLAIRs refined analysis
by GCN Circulars 11 Jul '25

11 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41063 SUBJECT: GRB 250704A: SVOM/ECLAIRs refined analysis DATE: 25/07/11 12:20:56 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> Authors: N. Dagoneau (CEA), U. Jacob (LUPM), J.X Cao (GXU), Y.H Cheng (SWIFAR, YNU), J.-L. Atteia, M. Brunet, O. Godet (IRAP), F. Cangemi, A. Coleiro (APC) Using the event-by-event data downloaded through the X-band ground station, we report further analysis of ECLAIRs observations of GRB 250704A (SVOM burst-id sb25070404). The burst that triggered ECLAIRs onboard (GCN 40934) consists of a single pulse with a duration of T90 = 9.0 +0.6/-0.5 s in the 4-120 keV energy band. The time-averaged spectrum of the burst from T0 - 1.50 s to T0 + 7.48 s (T0 = 2025-07-04T03:42:22) in the energy range 8-120 keV is best fit by a power-law model with a photon index of -1.3 +/- 0.2. With this model, the total 4-120 keV fluence, assuming the T90 measured, is 1.23 +/- 0.21 x 10^-6 erg/cm^2. All the quoted errors are at the 68% confidence level. 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: Nicolas Dagoneau (nicolas.dagoneau at cea.fr) View this GCN Circular online at https://gcn.nasa.gov/circulars/41063. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39114] LIGO/Virgo/KAGRA S250711q: Identification of a GW compact binary merger candidate
by GCN Circulars 11 Jul '25

11 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41062 SUBJECT: LIGO/Virgo/KAGRA S250711q: Identification of a GW compact binary merger candidate DATE: 25/07/11 04:36:24 GMT FROM: Jyotirmaya Mohanta at University of Tsukuba <s2430161(a)u.tsukuba.ac.jp> The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report: We identified the compact binary merger candidate S250711q during real-time processing of data from LIGO Hanford Observatory (H1), LIGO Livingston Observatory (L1), and Virgo Observatory (V1) at 2025-07-11 03:27:25.108 UTC (GPS time: 1436239663.108). The candidate was found by the cWB [1], cWB BBH [2], GstLAL [3], and MBTA [4] analysis pipelines. S250711q is an event of interest because its false alarm rate, as estimated by the online analysis, is 1.6e-09 Hz, or about one in 20 years. The event's properties can be found at this URL: https://gracedb.ligo.org/superevents/S250711q The classification of the GW signal, in order of descending probability, is BBH (>99%), Terrestrial (<1%), NSBH (<1%), or BNS (<1%). Assuming the candidate is astrophysical in origin, the probability that at least one of the compact objects is consistent with a neutron star mass (HasNS) is <1%. [5] Using the masses and spins inferred from the signal, the probability of matter outside the final compact object (HasRemnant) is <1%. [5] Both HasNS and HasRemnant consider the support of several neutron star equations of state for maximum neutron star mass. The probability that either of the binary components lies between 3 and 5 solar masses (HasMassGap) is <1%. The source chirp mass falls with highest probability in the bin (22.0, 44.0) solar masses, assuming the candidate is astrophysical in origin. Two sky maps are available at this time and can be retrieved from the GraceDB event page: * bayestar.multiorder.fits,0, an initial localization generated by BAYESTAR [6], distributed via GCN and SCiMMA notices about 31 seconds after the candidate event time. * bayestar.multiorder.fits,1, an initial localization generated by BAYESTAR [6], distributed via GCN and SCiMMA notices about 5 minutes after the candidate event time. The preferred sky map at this time is bayestar.multiorder.fits,1. For the bayestar.multiorder.fits,1 sky map, the 90% credible region is 2964 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 9738 +/- 2925 Mpc (a posteriori mean +/- standard deviation). For further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/. [1] Klimenko et al. PRD 93, 042004 (2016) doi:10.1103/PhysRevD.93.042004 [2] T. Mishra et al. PRD 105, 083018 (2022) doi:10.1103/PhysRevD.105.083018 [3] Tsukada et al. PRD 108, 043004 (2023) doi:10.1103/PhysRevD.108.043004 and Ewing et al. PRD 109, 042008 (2024) doi:10.1103/PhysRevD.109.042008 [4] Alléné et al. CQG 42, 105009 (2025) doi:10.1088/1361-6382/add234 [5] Chatterjee et al. ApJ 896, 54 (2020) doi:10.3847/1538-4357/ab8dbe [6] Singer & Price PRD 93, 024013 (2016) doi:10.1103/PhysRevD.93.024013 View this GCN Circular online at https://gcn.nasa.gov/circulars/41062. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39113] GRB 250702B,D,E/EP250702A: JCMT sub-mm observations at 350 GHz
by GCN Circulars 10 Jul '25

10 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41061 SUBJECT: GRB 250702B,D,E/EP250702A: JCMT sub-mm observations at 350 GHz DATE: 25/07/10 21:08:34 GMT FROM: alexandra.tetarenko(a)uleth.ca A.J. Tetarenko (ULethbridge), J. Bright (Oxford), G. Bower (EAO/JCMT), S. Graves (EAO/JCMT): The James Clerk Maxwell Telescope (JCMT) observed the position of GRB 250702B,D,E/EP250702A (GCNs [40906](https://gcn.nasa.gov/circulars/40906?view=group&limit=100), [40883](https://gcn.nasa.gov/circulars/40883?view=group&limit=100), [40885](https://gcn.nasa.gov/circulars/40885?view=group&limit=100), [40886](https://gcn.nasa.gov/circulars/40886?view=group&limit=100), [40890](https://gcn.nasa.gov/circulars/40890?view=group&limit=100), [40891](https://gcn.nasa.gov/circulars/40891?view=group&limit=100), ATels [17259](https://www.astronomerstelegram.org/?read=17259), [17261](https://www.astronomerstelegram.org/?read=17261)) on 2025 July 08 between ~08:50 - 12:30 UTC for 3 scans totalling 0.55 hrs on-source and 2025 July 09 between ~08:15 - 09:20 UTC for 2 scans totalling 1.05 hrs on-source. The observations were made at a central frequency of 850 um (350 GHz) with the SCUBA-2 instrument. We do not detect a target source at the previously reported VLA radio position (RA: 18:58:45.565, Dec: -07:52:26.42; GCN [41053](https://gcn.nasa.gov/circulars/41053?view=group&limit=100)) yielding a 3-sigma upper limit of 6.3 mJy from stacking all of the data. Extrapolating the previous radio detections with MeerKAT/VLA at 1.28/10 GHz of ~0.1/0.5 mJy (which imply a spectral index of ~1.3; GCN [41053](https://gcn.nasa.gov/circulars/41053?view=group&limit=100)) we would expect a clear detection at 350 GHz of ~50 mJy, suggesting a break in the spectrum between the cm and mm/sub-mm regions for this source. However, the recent ALMA detection at 97.5 GHz of ~2 mJy (GCN [41059](https://gcn.nasa.gov/circulars/41059)) taken nearly simultaneously with our JCMT observations, implies a flatter spectral index of ~0.6. Therefore, a more accurate estimate of the expected 350 GHz flux density at the time of our JCMT observations would be ~4 mJy, consistent with our 3-sigma upper limit. Given these constraints, the source appears to likely have an inverted optically thick spectrum extending into the sub-mm bands. *We thank the JCMT staff for rapidly scheduling these observations. The JCMT is operated by the EAO on behalf of ASIAA and NARIT. Additional funds for the construction of SCUBA-2 were provided by the Canada Foundation for Innovation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Maunakea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain.* View this GCN Circular online at https://gcn.nasa.gov/circulars/41061. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39112] GRB 250704B / EP250704a: 1.3 GHz MeerKAT Detection
by GCN Circulars 10 Jul '25

10 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41060 SUBJECT: GRB 250704B / EP250704a: 1.3 GHz MeerKAT Detection DATE: 25/07/10 20:58:22 GMT FROM: Genevieve Schroeder at Cornell University <genevieveschroeder(a)u.northwestern.edu> G. Schroeder (Cornell), L. Rhodes (TSI/McGill), W. Fong (Northwestern), T. Laskar (Utah), E. Berger (Harvard) report: We observed the location of the short-duration GRB 250704B/EP 250704A (Wang et al., GCN 40940; Li et al., GCNs 40941, 40956, Frederiks et al., GCN 40972; Wang et al., GCN 40978; Shimizu et al., GCN 41025) with the MeerKAT radio telescope under program MKT-24032 (PI Schroeder) at a central frequency of 1.3 GHz for a total of 2 hours with a mid time of 2025 July 10 at 00:07 UT (5.7 days post burst). In preliminary analysis, we detect the radio afterglow (Schroeder et al., GCN 41038; Ricci et al., GCN 41046), and measure a flux density of ~70 microJy. Further observations are planned. We thank the staff at the South African Radio Astronomy Observatory for scheduling these observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/41060. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39111] GRB 250702B,D,E / EP250702a: ALMA detection
by GCN Circulars 10 Jul '25

10 Jul '25

TITLE: GCN CIRCULAR NUMBER: 41059 SUBJECT: GRB 250702B,D,E / EP250702a: ALMA detection DATE: 25/07/10 18:59:43 GMT FROM: Kate D. Alexander at University of Arizona <katedenhamalexander(a)gmail.com> Kate D. Alexander (U of Arizona), James Miller-Jones (Curtin U), Adelle Goodwin, (Curtin U), Noah Franz (U of Arizona), Raffaella Margutti (UC Berkeley) Ryan Chornock (UC Berkeley), Dheeraj Pasham (Eureka Scientific/George Washington), Edo Berger (Harvard), Yvette Cendes (U of Oregon), and Collin Christy (U of Arizona) report on behalf of a larger collaboration: We observed the location of the unusual transient GRB 250702B,D,E / EP250702a (GCNs 40906, 40883, 40885, 40886, 40890, 40891) with the Atacama Large Millimeter/submillimeter Array (ALMA) at multiple frequencies (program 2023.1.01731.T, PI: Miller-Jones). On 2025 July 9 02:09:03 UT, 6.97 days after the first detection with the Einstein Probe (GCN 40906) and 6.51 days after the first Fermi trigger (GCN 40883), we clearly detected the source at a mean frequency of 97.5 GHz with a preliminary flux density of ~2 mJy. Further ALMA observations are planned. We thank the ALMA staff for quickly scheduling these observations and for providing the quick-look reduction. View this GCN Circular online at https://gcn.nasa.gov/circulars/41059. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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