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

April 2025

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[vsnet-grb-info 38206] GRB 250419A: AKO Optical Afterglow Detection
by GCN Circulars 19 Apr '25

19 Apr '25
TITLE: GCN CIRCULAR NUMBER: 40180 SUBJECT: GRB 250419A: AKO Optical Afterglow Detection DATE: 25/04/19 19:19:16 GMT FROM: Mohammad Odeh at Al Khatim Observatory M44 <mshodeh(a)gmail.com> Mohammad Odeh (Al-Khatim Observatory, AKO, operated by the International Astronomical Center in Abu Dhabi, UAE), and Shaikha Alshamsi, and Nidhal Guessoum (American University of Sharjah, UAE), report: We observed the field of GRB 250419A detected by SVOM (Wang et al., GCN 40168), using our 0.36m f/7.7 robotic telescope. The observation session began on 19 April 2025 at 15:49 UT and continued until 18:48 UT, with a midpoint at 17:18 UT, approximately 14.8 hours after the trigger. We obtained multiple 180-second exposures using the Ic filter. The optical afterglow was clearly detected at: R.A. (J2000): 13:29:37.30 Dec. (J2000): +07:02:27.7 Our detection is consistent with the results of (López et al., GCN 40169; Xin et al., GCN 40170; Zheng et al., GCN 40171; Kumar et al., GCN 40172; Lipunov et al., GCN 40179). The following observation was calculated using the Atlas catalogue as a reference: ---------------------------------------------------------------------------- - ObsTime (mid), Exposure (sec), Filter, Mag ---------------------------------------------------------------------------- - 2025-04-19T17:18:06Z, 57 x 180s (stacked), Ic, 18.7 +/- 0.16 ---------------------------------------------------------------------------- - The magnitude is not corrected for galactic extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/40180. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 38205] GRB 250419A: MASTER optical afterglow observation
by GCN Circulars 19 Apr '25

19 Apr '25
TITLE: GCN CIRCULAR NUMBER: 40179 SUBJECT: GRB 250419A: MASTER optical afterglow observation DATE: 25/04/19 17:43:59 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov(a)xray.sai.msu.ru> V.Lipunov, A.Kuznetsov, G.Antipov, V.Topolev, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Chasovnikov, Ya.Kechin, V.Senik, K. Labzina, D.Vlasenko, E.Gorboskoy(Lomonosov MSU), O.Gress, N.Budnev (ISU), C.Francile, F. Podesta, R.Podesta, E. Gonzalez (OAFA), A.Sosnovskij (Crao RAS), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity), R.Rebolo (The Instituto de Astrofisica de Canarias), D.Buckley (SAAO), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro AstrophysicsObservatory) MASTER-OAFA robotic telescope  (Global MASTER-Net: http://observ.pereplet.ru,Lipunov et al., 2010, Advances in Astronomy, v. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the SVOM Alert 250419.10 (trigger No 1745029772,13h 29m 32.88s , +07d 05m 09.6s, R=0.1525, Wang et al. GCN 40168, Ocelotl López et al. GCN40169, Xin etl al. GCN40170) 3960 sec after trigger time at 2025-04-19 03:35:32 UT, with upper limit up to 19.9 mag. The observations began at zenith distance = 39 deg. The sun altitude is -66.0 deg. The galactic latitude b = 68 deg., longitude l = 330 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2847195 We obtained the following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment 3991 | 2025-04-19 03:35:32 | MASTER-OAFA | (13h 29m 02.64s , +07d 04m 50.6s) | C | 60 | 19.7 | 5446 | 2025-04-19 03:59:47 | MASTER-OAFA | (13h 28m 54.60s , +07d 03m 09.9s) | C | 60 | 19.7 | 6895 | 2025-04-19 04:23:56 | MASTER-OAFA | (13h 29m 35.13s , +07d 25m 23.4s) | C | 60 | 19.6 | 6955 | 2025-04-19 04:23:56 | MASTER-OAFA | (13h 29m 35.12s , +07d 25m 23.4s) | C | 180 | 19.9 | Coadd 8383 | 2025-04-19 04:48:45 | MASTER-OAFA | (13h 29m 28.53s , +07d 25m 00.4s) | C | 60 | 19.5 | 9666 | 2025-04-19 05:10:08 | MASTER-OAFA | (13h 29m 34.89s , +07d 26m 24.5s) | C | 60 | 19.4 | 10159 | 2025-04-19 05:18:20 | MASTER-OAFA | (13h 29m 31.07s , +07d 26m 26.7s) | C | 60 | 19.5 | Filter C is a clear (unfiltred) band. There is MASTER OT J132937.28+070227.8 since 2025-04-19 03:35:32 with m_OT=18.0 (unfiltered, Lipunov et al. 2010, 2019, 2022, 2023) up to 2025-04-19 05:18:20UT at SVOM VT position (GCN 40170 Xin et al.) The reduction will be continued View this GCN Circular online at https://gcn.nasa.gov/circulars/40179. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 38204] Fermi-LAT Gamma-ray Observations of IceCube-250416A
by GCN Circulars 19 Apr '25

19 Apr '25
TITLE: GCN CIRCULAR NUMBER: 40178 SUBJECT: Fermi-LAT Gamma-ray Observations of IceCube-250416A DATE: 25/04/19 16:52:22 GMT FROM: Simone Garrappa at Weizmann Institute of Science <simone.garrappa(a)weizmann.ac.il> S. Garrappa (Weizmann Institute of Science), C. Bartolini (INFN Bari), S. Buson (DESY, Univ. of Wuerzburg) and L. Pfeiffer (Univ. of Wuerzburg) on behalf of the Fermi-LAT collaboration: We report an analysis of observations of the vicinity of the high-energy IC250416A neutrino event (GCN 40153) 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 2025-04-16 at 18:32:14.97 (T0) with J2000 position RA = 83.1 (+0.57, -0.58) deg, Decl. = 15.64 (+0.49, -0.5) deg 90% PSF containment (J2000). No cataloged gamma-ray sources are found within the 90% IC250416A 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 IC250416A 90% confidence localization. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IC250416A best-fit position, the >100 MeV flux upper limit (95% confidence) is < 3.1 e-10 ph cm^-2 s^-1 for ~16-years (2008-08-04 / T0), < 7.2e-09 (<1.2e-07) 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/40178. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 38203] GRB 250407A: rest-frame energetics from Konus-Wind observation
by GCN Circulars 19 Apr '25

19 Apr '25
TITLE: GCN CIRCULAR NUMBER: 40177 SUBJECT: GRB 250407A: rest-frame energetics from Konus-Wind observation DATE: 25/04/19 14:12:21 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: Assuming the spectrum and the observer-frame energetics of the very bright GRB 250407A (GCN 40104) measured by Konus-Wind (GCN 40121); the redshift z=1.36 (Schneider et al., GCNs 40175); and a standard cosmology with H_0 = 67.3 km/s/Mpc, Omega_M = 0.315, and Omega_Lambda = 0.685 (Planck Collaboration, 2014); we estimate the burst isotropic energy release E_iso to (7.86 ± 0.20)x10^53 erg, the isotropic peak luminosity L_iso to (1.66 ± 0.06)x10^54 erg/s, the rest-frame peak energy of the time-integrated spectrum Ep,i,z to (1530 ± 110) keV, and the rest-frame peak energy at the peak of the emission Ep,p,z to (1970 ± 250) keV. With the obtained estimates, GRB 250407A is among 10 most luminous (and 50 most energetic) GRBs detected by Konus-Wind. The burst is consistent with 68% prediction bands for both 'Amati' and 'Yonetoku' relations derived for the sample of >300 long KW GRBs with known redshifts (Tsvetkova et al., 2017; Tsvetkova et al., 2021), see http://www.ioffe.ru/LEA/GRBs/GRB250407_T56895/GRB250407A_rest_frame.pdf All the quoted errors are estimated at the 68% confidence level. All the presented results are preliminary. View this GCN Circular online at https://gcn.nasa.gov/circulars/40177. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 38202] GRB 250419A: Swift-XRT localisation
by GCN Circulars 19 Apr '25

19 Apr '25
TITLE: GCN CIRCULAR NUMBER: 40176 SUBJECT: GRB 250419A: Swift-XRT localisation DATE: 25/04/19 13:15:36 GMT FROM: K.L. Page at U Leicester <klp5(a)leicester.ac.uk> K.L. Page, P.A. Evans (U. Leicester) and J.A. Kennea (PSU) report on behalf of the Swift-XRT team: The XRT afterglow of the SVOM/ECLAIRs-detected burst GRB 250419A, reported in GCN Circ. 40173, is located at a position of RA, Dec = 202.40554, 7.03987 which is equivalent to RA (J2000): 13h 29m 37.33s Dec (J2000): +07d 02' 23.5" with an uncertainty of 3.8 arcsec (radius, 90% confidence). This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/40176. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 38201] GRB 250407A: GTC/OSIRIS+ spectroscopic redshift z = 1.36
by GCN Circulars 19 Apr '25

19 Apr '25
TITLE: GCN CIRCULAR NUMBER: 40175 SUBJECT: GRB 250407A: GTC/OSIRIS+ spectroscopic redshift z = 1.36 DATE: 25/04/19 13:09:50 GMT FROM: Daniele B. Malesani at IMAPP / Radboud University <d.malesani(a)astro.ru.nl> B. Schneider (LAM), D. B. Malesani (DAWN/NBI and Radboud), A. de Ugarte Postigo (LAM), A. Martin-Carrillo (UCD), J. F. Agui Fernandez (CAHA), M. A. Aloy (UV), J. P. U. Fynbo (DAWN/NBI), L. Galbany (IEEC-CSIC), S. Geier (GTC), L. Izzo (INAF/OACN and DARK/NBI), G. Lombardi (GTC), N. A. Rakotondrainibe (LAM), N. R. Tanvir (Univ. Leicester), C. C. Thoene (AbAO), A. Perez (GTC) and R. Scarpa (GTC), report: We observed the optical afterglow of the GRB 250407A (Fermi GBM team, GCN 40104; Preis & Greiner, GCN 40105; Mukherjee & Meegan, GCN 40114; Molkov et al., GCN 40110; Dichiara et al., GCN 40113; Ducoin et al., GCN 40117; Zheng et al., GCN 40119; Wang et al., GCN 40120; Frederiks et al., GCN 40121; Williams et al., GCN 40123; Pérez-Fournon et al., GCN 40125; Kozyrev et al., GCN 40127; Pankov et al., GCN 40133; deGraw et al., GCN 40135) using the 10.4 m GTC located at the Roque de los Muchachos Observatory in the island of La Palma (Spain) equipped with the OSIRIS+ instrument. In a 60 s acquisition image in the r-band, starting on 2025-04-17 at 21:27:11 UT (10.24 after the Fermi trigger), an object is detected at the position of the optical afterglow (Zheng & Filippenko, GCN 40116), with a magnitude r = 22.48 +/- 0.06 (AB, calibrated against nearby Pan-STARRS objects). At a consistent location, the Legacy Survey also reveals a source, the likely GRB host galaxy, with a somehow fainter magnitude r = 22.65. In our observation the target flux is thus likely dominated by the host, possibly with some transient contribution. Our spectroscopic observations started on 2025-04-17 at 21:32:03 UT (10.24 days after the Fermi trigger) and consisted of 3x900 s exposures with grism R1000R, covering the range between 5100 and 10,000 AA. In a preliminary reduction of the spectra, we clearly detect a continuum over the entire covered range. From the detection of multiple absorption features, including Fe II, Mg II, and Mg I, we infer a redshift of z = 1.36. At a consistent redshift, an emission line is also detected, which we interpret as the [O II] doublet from the host galaxy. We thus conclude that GRB 250407A is at redshift z = 1.36. View this GCN Circular online at https://gcn.nasa.gov/circulars/40175. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 38200] GRB 250419A: VLT/X-shooter spectroscopic redshift z = 0.845
by GCN Circulars 19 Apr '25

19 Apr '25
TITLE: GCN CIRCULAR NUMBER: 40174 SUBJECT: GRB 250419A: VLT/X-shooter spectroscopic redshift z = 0.845 DATE: 25/04/19 09:56:04 GMT FROM: Aishwarya L Thakur at INAF-IAPS, Rome <aishth(a)outlook.com> A. L. Thakur (INAF-IAPS), M. Garnichey (LUX-Paris Obs.), G. Corcoran (UCD), A. J. Levan (Radboud), D. B. Malesani (DAWN/NBI and Radboud)​​, A. Martin-Carrillo (UCD), G. Pugliese (API-UvA), A. Saccardi (CEA/Irfu), S. D. Vergani (LUX-Paris Obs.) report on behalf of the Stargate collaboration: We observed the optical counterpart (Lopez et al., GCN 40169; Xin et al., GCN 40170; Zheng et al., GCN 40171; Kumar et al., GCN 40172) of the SVOM/ECLAIRs GRB 250419A (Wang et al., GCN 40168) using the ESO/VLT UT3 (Melipal) equipped with the X-shooter spectrograph. Observations started on 2025 April 19 at 07:10:59 UT (4.69 hr after the burst). Our spectra cover the wavelength range 3000-21000 AA and consist of 4 exposures of 600 s each. Seeing conditions were very poor at ~3". In a preliminary reduction of the spectra, we clearly detect a continuum over the entire wavelength range. From the detection of multiple absorption features, including Fe II, Mg II, Mg I, Ca II and Ca I we infer a redshift of z = 0.845. We note that no object is visible in the Legacy Survey at the coordinates of the optical transient (López et al., GCN 40169; Xin et al., GCN 40170), down to a magnitude r ~ 24. This is consistent with the lack of emission lines in our spectrum. We acknowledge the prompt response and excellent support of the ESO observing staff in Paranal, particularly from Martina Baratella. This analysis was carried out with the help of the zHunter tool (https://doi.org/10.5281/zenodo.15189495) View this GCN Circular online at https://gcn.nasa.gov/circulars/40174. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 38199] GRB 250419A: Swift-XRT refined Analysis
by GCN Circulars 19 Apr '25

19 Apr '25
TITLE: GCN CIRCULAR NUMBER: 40173 SUBJECT: GRB 250419A: Swift-XRT refined Analysis DATE: 25/04/19 08:09:20 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> K.L. Page (U. Leicester), B. Sbarufatti (INAF-OAB), C. Salvaggio (INAF-OAB), M. Ferro (INAF-OAB), S. Dichiara (PSU), J.A. Kennea (PSU), D.N. Burrows (PSU), A.P. Beardmore (U. Leicester) and P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team: We have analysed 2.0 ks of XRT data for the SVOM/ECLAIRs-detected burst GRB 250419A (SVOM burst-id sb25041901), from 3.8 ks to 9.6 ks after the SVOM/ECLAIRs trigger. The data are entirely in Photon Counting (PC) mode. The light curve is consistent with a constant source of mean count rate 1.1e-01 ct/sec. A power-law fit gives an index of 0.3 (+0.6, -0.5). Despite a constant count rate, we are likely detecting the GRB afterglow. The source is consistent with the position of the optical afterglow detected by the SVOM/COLIBRÍ (FM-GFT) telescope (Lopez et al., GCN 40169), SVOM/VT (Xin et al., GCN 40170), KAIT (Zheng et al., GCN 40171), GOTO (Kumar et al., GCN 40172). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.9 (+0.4, -0.3). The best-fitting absorption column is 7.7 (+9.9, -5.5) x 10^20 cm^-2, consistent with the Galactic value of 2.2 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.5 x 10^-11 (4.1 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 7.7 (+9.9, -5.5) x 10^20 cm^-2 Galactic foreground: 2.2 x 10^20 cm^-2 Excess significance: <1.6 sigma Photon index: 1.9 (+0.4, -0.3) The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00019724. This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/40173. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 38198] GRB 250419A: GOTO optical counterpart detection
by GCN Circulars 19 Apr '25

19 Apr '25
TITLE: GCN CIRCULAR NUMBER: 40172 SUBJECT: GRB 250419A: GOTO optical counterpart detection DATE: 25/04/19 07:52:06 GMT FROM: Amit Kumar at Royal Holloway - UoL/ U of Warwick, UK <amitkundu515(a)gmail.com> A. Kumar, G. Ramsay, B. P. Gompertz, 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 the SVOM GRB 250419A (sb25041901; Wang et al., GCN 40168). The observations were conducted with GOTO-North between 2025-04-19 02:55:03 (25.5 min post-trigger) and 2025-04-19 04:03:07 (93.6 min post-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. We detect the reported optical afterglow, discovered by SVOM/COLIBRÍ FM-GFT (López et al., GCN 40169) and confirmed by SVOM/VT (Xin et al., GCN 40170), and KAIT (Zheng et al., GCN 40171). We obtained the following 3-sigma detections of the optical counterpart: Date | T-T0 (min) | Filter | Mag (AB) --------------------------------------------------------------------------- 2025-04-19T02:55:03 | 25.5 | L | 18.22 ± 0.05 2025-04-19T04:03:07 | 93.6 | L | 18.39 ± 0.07 Based on our observations, the afterglow exhibits a power-law decay with an index of α = -0.12 between these two epochs. We find no evidence of the source prior to the GRB trigger time in archival GOTO observations taken 14.07 min before the trigger, down to a 3-sigma L-band upper limit of 20.26 mag. Magnitudes were calibrated using ATLAS-REFCAT2 (Tonry et al. 2018) and are not corrected for Galactic extinction. Observations are ongoing. GOTO (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/40172. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 38197] GRB 250419A: KAIT optical afterglow observations
by GCN Circulars 19 Apr '25

19 Apr '25
TITLE: GCN CIRCULAR NUMBER: 40171 SUBJECT: GRB 250419A: KAIT optical afterglow observations DATE: 25/04/19 06:04:42 GMT FROM: Weikang Zheng at UC Berkeley <weikang(a)berkeley.edu> WeiKang Zheng (UCB), Xuhui Han (NAOC), Pinpin Zhang (NAOC) and Alexei V. Filippenko (UCB) report on behalf of the KAIT GRB team: The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at Lick Observatory, observed the field of SVOM GRB 250403A (Wang et al., GCN 40168) with a set of clear (roughly R) images starting at 1.47 hours after the trigger. We clearly detected the optical afterglow (López et al., GCN 40169; Xin et al., GCN 40170) in our single image. The afterglow is measured at 18.0 +/- 0.2 mag (Vega) at 1.47 hours after the trigger. It remained to be similar brightness for about 40 minutes then decayed after that. Observation is on going. View this GCN Circular online at https://gcn.nasa.gov/circulars/40171. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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