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

[vsnet-grb-info 37117] EP250108A / SN 2025kg: Upper limits from a neutrino search with IceCube
by GCN Circulars 31 Jan '25

31 Jan '25

TITLE: GCN CIRCULAR NUMBER: 39108 SUBJECT: EP250108A / SN 2025kg: Upper limits from a neutrino search with IceCube DATE: 25/01/31 15:15:59 GMT FROM: Jessie Thwaites at IceCube/U Wisc-Madison <thwaites(a)wisc.edu> The IceCube Collaboration (http://icecube.wisc.edu/) reports: IceCube has performed a search for track-like muon neutrino events arriving from the direction of the FBOT EP250108A in a time window of [-600, +5000] seconds from the initial trigger reported by Einstein Probe (GCN 38861), during which time IceCube was collecting good quality data (2025-01-08 12:20:28.34 UTC to 2025-01-08 13:53:48.34 UTC). Zero track-like events are found coincident with the position of the FBOT. We accordingly derive a time-integrated muon-neutrino flux upper limit for this source of E^2 dN/ dE = 0.29 GeV cm^-2 at 90% CL, under the assumption of an E^-2 power law. 90% of events IceCube would detect from a source at this declination with an E^-2 spectrum have energies in the approximate energy range between 60 TeV and 20 PeV. A subsequent search was performed with a time window of [-2, +12] days with respect to the initial trigger (2025-01-06 12:30:28.34 UTC to 2025-01-20 12:30:28.34 UTC). In this case, we report a p-value of 1.0, consistent with background expectation. We accordingly derive a time-integrated muon-neutrino flux upper limit for this source of E^2 dN/ dE = 0.34 GeV cm^-2 at 90% CL, under the assumption of an E^-2 power law. 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. [1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021) View this GCN Circular online at https://gcn.nasa.gov/circulars/39108. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 37116] GRB 250129A: SAO RAS optical observations
by GCN Circulars 31 Jan '25

31 Jan '25

TITLE: GCN CIRCULAR NUMBER: 39107 SUBJECT: GRB 250129A: SAO RAS optical observations DATE: 25/01/31 12:29:18 GMT FROM: Moskvitin Alexander at SAO RAS <mosk(a)sao.ru> A. Moskvitin, O. Spiridonova, Yu. Sotnikova (SAO RAS), A. Ghosh, S. Razzaque (CAPP, University of Johannesburg) We observed the field of GRB 250129A (Beardmore et al., GCN 39066) with the SAO RAS 1-m telescope Zeiss-1000 on January 30, 23:46:43 -- January 31, 00:19:22 UT (t_mid - T0 = 43.298 hours = 1.8041 days). We obtained 5 x 300 sec. images in Rc band. The OT (Francile et al., GCN 39065; GCN 39075, Beardmore et al., GCN 39066, Schneider et al., GCN 39071, Belkin et al., GCN 39072; Izzo et al., GCN 39073; Izzo and Malesani, GCN 39074; Ghosh et al., GCN 39077; Schneider et al., GCN 39078; Brivio et al., GCN 39079; Siegel and Beardmore, GCN 39085; Zheng and Filippenko, GCN 39090; GCN 39102; Schlekat et al., GCN 39091; Antier et al., GCN 39096; Odeh et al., GCN 39097; Ferro et al., GCN 39098; Bochenek and Perley, GCN 39099; Malesani et al., GCN 39100; Romanov, GCN 39101; Watson et al., GCN 39104; Vinko et al., GCN 39105; Akl et al., GCN 39106) is clearly detected in the stacked frame with the brightness of R = 19.65 +/- 0.13 (calibrated against R2 magnitudes of nearby UNSO-B1 stars and not corrected for the MW extinction). View this GCN Circular online at https://gcn.nasa.gov/circulars/39107. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 37115] GRB 250129A: COLIBRÍ Continuing Detection of the Afterglow
by GCN Circulars 31 Jan '25

31 Jan '25

TITLE: GCN CIRCULAR NUMBER: 39106 SUBJECT: GRB 250129A: COLIBRÍ Continuing Detection of the Afterglow DATE: 25/01/31 11:10:13 GMT FROM: Dalya Akl at American Uni. SHJ <dalyaakl.d(a)gmail.com> Dalya Akl (AUS), Alan M. Watson (UNAM), Camila Angulo (UNAM), Sarah Antier (OCA/IJCLAB), Benjamin Schneider (LAM), Rosa L. Becerra (Università degli Studi di Roma Tor Vergata), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Jean-Luc Atteia (IRAP), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Francis Fortin (IRAP), Jean-Grégoire Ducoin (CPPM), Francesco Magnani (CPPM), and Margarita Pereyra (UNAM) report: We continued imaging the field of the Swift GRB 250129A (Beardmore et al., GCN Circ. 39066) during the commissioning of the COLIBRÍ (SVOM/F-GFT) telescope at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir in Mexico. We observed with the OGSE engineering test camera in a red filter approximating SDSS r starting at 2025-01-31 07:30:00 UTC. Compared to our observations from the previous night, we see a decay with an index of about -1.8 between T+30 and T+52 hours, less steep than the very sharp decline reported by (Zheng & Filippenko, GCN Circ. 39102) from T+28.5 to T+33.5 hours. Further observations are planned. We warmly thank the COLIBRÍ engineering team and the staff of the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir. We warmly thank the GRANDMA IJCLAB team and S. Karpov for the access of the STDWeb service for STDPipe. View this GCN Circular online at https://gcn.nasa.gov/circulars/39106. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 37114] GRB 250129A: optical photometry from Konkoly
by GCN Circulars 31 Jan '25

31 Jan '25

TITLE: GCN CIRCULAR NUMBER: 39105 SUBJECT: GRB 250129A: optical photometry from Konkoly DATE: 25/01/31 10:23:30 GMT FROM: Jozsef Vinko at Konkoly Observator <vinko(a)konkoly.hu> GRB 250129A: optical photometry from Konkoly J. Vinko, A. Horti-David, R. Konyves-Toth, Zs. Bora, L. Kriskovics, A. Pal, R. Szakats (Konkoly Observatory, Hungary) We report detection and photometry of the optical afterglow of GRB 250129A (Beardmore et al., GCN 39066) taken with the RC80 robotic telescope at Piszkesteto Station of Konkoly Observatory, Hungary. The observations started on 2025-01-29 23:35:21 UT, 18.84 hours after the trigger. 5 sets of 300 sec frames were collected through Sloan g', r'- and i' bands. The optical afterglow (Francile et al., GCN 39065; Beardmore et al., GCN 39066; Schneider et al., GCN 39071; Belkin et al., GCN 39072; Izzo et al., GCN 39073; Izzo & Malesani, GCN 39074; Gosh et al., GCN 39077; Schneider et al., GCN 39078; Brivio et al., GCN 39079; Siegel et al., GCN 39085; Zheng et al. GCN 39090; Schlekat et al., GCN 39091; Antier et al., 39096; Odeh et al., GCN 39097; Ferro et al., GCN 39098; Bochenek et al., GCN 39099; Malesani et al., GCN 39100; Romanov, GCN 39101; Zheng & Filippenko, GCN 39102; Watson et al. GCN 39104) was detected on the stacked frames with the following magnitudes, calibrated via nearby PS1 stars: Date UT-middle t-T0(days) Exp(s) g'(AB) r'(AB) i'(AB) 2025-01-30 00:13:39 0.7849 5x300 20.32 (0.21) 19.29 (0.08) 19.12 (0.10) The magnitudes above are not corrected for galactic extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/39105. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 37113] GRB 250129A: COLIBRÍ Optical Observations
by GCN Circulars 31 Jan '25

31 Jan '25

TITLE: GCN CIRCULAR NUMBER: 39104 SUBJECT: GRB 250129A: COLIBRÍ Optical Observations DATE: 25/01/31 07:13:32 GMT FROM: Alan Watson at UNAM <alan(a)astro.unam.mx> Alan M. Watson (UNAM), Camila Angulo (UNAM), D. Akl (AUS), S. Antier (OCA), Benjamin Schneider (LAM), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Jean-Luc Atteia (IRAP), Rosa Becerra (Università degli Studi di Roma Tor Vergata), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Francis Fortin (IRAP), J.-G. Ducoin (CPPM), Francesco Magnani (CPPM) and Margarita Pereyra (UNAM) report: We imaged the field of the Swift GRB 250129A (Beardmore et al., GCN Circ. 39066) during the commissioning of the COLIBRÍ (SVOM/F-GFT) telescope at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir in Mexico. We observed with the OGSE engineering test camera in a red filter that approximates SDSS r from 2025-01-30 07:01 to 12:54 UTC. In the subset of our data from 2025-01-30 12:01 to 12:54, from 31.27 to 32.15 hours after the event, with a total exposure of 2220 seconds, we clearly detect the afterglow with r = 19.38 +/- 0.04 This magnitude is not corrected for Galactic extinction. The data were reduced using custom software and then analysed and calibrated against the PS1 catalog using the STDWeb service. Further observations are planned. We warmly thank the COLIBRÍ engineering team and the staff of the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir. We warmly thank the GRANDMA IJCLAB team and S. Karpov for the access of the STDWeb service for STDPipe. View this GCN Circular online at https://gcn.nasa.gov/circulars/39104. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 37112] GRB 250128B: VLA possible radio detection
by GCN Circulars 31 Jan '25

31 Jan '25

TITLE: GCN CIRCULAR NUMBER: 39103 SUBJECT: GRB 250128B: VLA possible radio detection DATE: 25/01/31 01:38:41 GMT FROM: Genevieve Schroeder at Cornell University <genevieveschroeder(a)u.northwestern.edu> G. Schroeder (Cornell), T. Laskar (Utah), W. Fong, J. Rastinejad (Northwestern) report: We observed the position of the short GRB 250128B (Evans et al., GCN 39058; Fermi GBM team, GCN 39057) with the Karl G. Jansky Very Large Array (VLA) under program 25A-063 (PI: Schroeder) beginning on 2025 Jan 29 at 10:05 UT (0.74 days post-burst) for 0.75 hours at a mean frequency of 6 GHz. Based on preliminary analysis, within the enhanced XRT position (Evans et al., GCN 39069) we find a possible source with a peak flux density of ~20 uJy at the position: RA(J2000): 15:25:42.032 Dec(J2000): -00:32:22.72 with an uncertainty of 0.1 arcsec in each coordinate. This position is ~2 arcsec offset from the optical/near IR sources reported in Yang et al. (GCN 39084) and Rastinejad et al. (GCN 39088). At present we cannot determine if this possible source is associated with the burst. We note that these observations were taken 2.7 hr prior to those reported in Ricci et al. (GCN 39093). We thank the VLA staff for quickly approving and executing these observations. Further observations are planned to assess the temporal behavior of the possible source. View this GCN Circular online at https://gcn.nasa.gov/circulars/39103. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 37111] GRB 250129A: continued KAIT observations indicating steep decay after 28.5h
by GCN Circulars 30 Jan '25

30 Jan '25

TITLE: GCN CIRCULAR NUMBER: 39102 SUBJECT: GRB 250129A: continued KAIT observations indicating steep decay after 28.5h DATE: 25/01/30 22:40:51 GMT FROM: Weikang Zheng at UC Berkeley <weikang(a)berkeley.edu> WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on behalf of the KAIT GRB team: The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at Lick Observatory, continued observing the afterglow of the GRB 250129A (Francile et al., GCN 39065; Beardmore et al., GCN 39066; Schneider et al., GCN 39071; Belkin et al., GCN 39072; Izzo et al., GCN 39073; Izzo & Malesani, GCN 39074; Gosh et al., GCN 39077; Schneider et al., GCN 39078; Brivio et al., GCN 39079; Siegel et al., GCN 39085; Zheng et al. GCN 39090; Schlekat et al., GCN 39091; Antier et al., 39096; Odeh et al., GCN 39097; Ferro et al., GCN 39098; Bochenek et al., GCN 39099; Malesani et al., GCN 39100; Romanov, GCN 39101) in the clear (roughly R) band. Observation started at ~28.5h after the burst and lasted for ~5.0h. The OT was still clearly detected in every individual image. Our photometry results show that the OT was in a single power-law decay phase, decayed from ~18.6 mag (~28.5h) to ~19.5 mag (~33.5h) with a decay index of ~4.1, much steeper compared to the value of ~0.85 reported by Bochenek et al. (GCN 39099). This indicating the OT is likely in a post jet-break phase. View this GCN Circular online at https://gcn.nasa.gov/circulars/39102. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 37110] GRB 250129A: iTelescope optical observation
by GCN Circulars 30 Jan '25

30 Jan '25

TITLE: GCN CIRCULAR NUMBER: 39101 SUBJECT: GRB 250129A: iTelescope optical observation DATE: 25/01/30 20:15:55 GMT FROM: Filipp Dmitrievich Romanov at Amateur astronomer <filipp.romanov.27.04.1997(a)gmail.com> I observed the field of GRB 250129A (Beardmore et al., GCN Circ. 39066) remotely using telescope T11 (0.51-m f/6.8 reflector + CCD + f/4.5 focal reducer) of iTelescope.Net (located in Utah Desert Remote Observatory at Great Basin Desert, Beryl Junction, Utah, USA) on 2025-01-30. Five images (exposure times of 300 seconds, BINx1) were obtained with Rc filter. I detected the optical afterglow in all images in the UVOT position. I measured the magnitude of it = 19.7 +/- 0.2 in the stacked image (mid time 13:11:06 UT = 32.43 h. after the trigger) compared to r magnitudes of nearby stars from Pan-STARRS DR1 catalogue (Chambers et al., 2016). Magnitude was not corrected for Galactic extinction. Stacked image: https://www.flickr.com/photos/filipp-romanov/54297183051/ F. D. Romanov (AAVSO). View this GCN Circular online at https://gcn.nasa.gov/circulars/39101. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 37109] GRB 250129A: NOT optical observations of continuining activity
by GCN Circulars 30 Jan '25

30 Jan '25

TITLE: GCN CIRCULAR NUMBER: 39100 SUBJECT: GRB 250129A: NOT optical observations of continuining activity DATE: 25/01/30 17:47:55 GMT FROM: Daniele B. Malesani at IMAPP / Radboud University <d.malesani(a)astro.ru.nl> D. B. Malesani (DAWN/NBI), K. E. Heintz (DAWN/NBI), B. P. Gompertz (Birmingham), A. Martin-Carrillo (UCD), A. M. Bochenek (LJMU), R. Brivio (INAF/OABr), A. M. Kadela (NOT, NBI), B. N. Hauptmann (NOT and DTU Space), report on behalf of a larger collaboration: We observed the nice optical afterglow of GRB 250129A (Beardmore et al., GCN 39066) using the Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. Seeing conditions were sub-optimal, around 2". Observations were carried out in the r and i filters (exposure time of 3x200 s each). At a mean epoch of Jan 30.0916 UT (21.44 hr after the trigger), we measure for the afterglow r = 19.24 +- 0.03 (AB), calibrated against nearby objects from the Pan-STARRS catalog. We note that this value is ~0.35 mag fainter than the measurement reported at a later epoch by Bochenek & Perley (24.1 hr after trigger; GCN 39099). Accurate relative comparison using a shared set of calibration stars confirms the rebrightening. Flaring was thus still ongoing even ~24 hr after the trigger, continuing the earlier trend highlighted by Belkin et al. (GCN 39072), Francile et al. (GCN 39075), Brivio et al. (GCN 39079), Zheng & Filippenko (GCN 39090), and Antier et al. (GCN 39096). We encourage further follow-up of this unusual event at all wavelengths. View this GCN Circular online at https://gcn.nasa.gov/circulars/39100. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 37108] GRB 250129a: Liverpool Telescope optical follow-up
by GCN Circulars 30 Jan '25

30 Jan '25

TITLE: GCN CIRCULAR NUMBER: 39099 SUBJECT: GRB 250129a: Liverpool Telescope optical follow-up DATE: 25/01/30 14:06:13 GMT FROM: A. Bochenek at Liverpool John Moores University <a.m.bochenek(a)2023.ljmu.ac.uk> A. Bochenek and D. A. Perley (LJMU) report: We observed the field of GRB250129a (Beardmore et al., GCN 39066) using the IO:O optical camera on the 2m robotic Liverpool Telescope. We obtained 6x90s exposures in the SDSS r’ filter starting at 2025-01-30 04:53:17 UT, approximately 24.1 hours after the trigger. Three of the images had to be discarded due to autoguider issues. We report a detection in the stacked images of r = 18.91 ± 0.03 mag. Our detection is consistent with the re-brightening (Brivio et al., GCN 39079, Zheng et al., GCN 39090) and subsequent observations of the afterglow (Odeh et al., GCN39097, Ferro et al. GCN39098). This implies slow decay, approx. 2 magnitudes in r-band from (clear) R ~17.1 at 6.9h post trigger (Zheng et al., GCN 39090) to this work’s r = 18.91 at 24.1h, with the decay index of approximately ~0.85. The photometry was obtained using nearby PanSTARRS standards and was not corrected for extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/39099. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0