July 2024 - vsnet-grb-info - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-grb-info 34829] GRB 240727A: Correction to time in GCN36960
by GCN Circulars 28 Jul '24

28 Jul '24

TITLE: GCN CIRCULAR NUMBER: 36965 SUBJECT: GRB 240727A: Correction to time in GCN36960 DATE: 24/07/28 14:30:48 GMT FROM: Ulisse Quadri at Bassano Bresciano Observatory <osservatoriobassano(a)gmail.com> U.Quadri, L.Strabla and P.Madurini (Bassano Bresciano Astronomical Observatory)report: The times given in GCN36960 are incorrect. The correct times are: Start T0+ End T0+ Vlim 15.97 hour 17.06 hour 20 Magnitudes were estimated with the pan-STARRS catalog. We apologize for the mistake. View this GCN Circular online at https://gcn.nasa.gov/circulars/36965. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34828] GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit
by GCN Circulars 28 Jul '24

28 Jul '24

TITLE: GCN CIRCULAR NUMBER: 36964 SUBJECT: GRB 240727A: Osservatorio Astronomico Nastro Verde upper limit DATE: 24/07/28 11:41:46 GMT FROM: Nello Ruocco at Osservatorio Nastro Verde - Sorrento (Naples) - Italy - MPC Code C82 <osservatorionastroverde(a)gmail.com> Nello Ruocco at Osservatorio Nastro Verde - Sorrento (Naples) - Italy in a large collaboration with: M.G. Dainotti (National Astronomical Observatory of Japan), Y. Niino (Tokyo University, Institute of Astronomy), K. Kalinowski (Aarhus University, Department of Physics and Astronomy), B. De Simone (Universita' degli Studi Di Salerno) report: We image the field of GRB 240727A (Trigger 1245074 T. M. Parsotan (GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL) and B. Sbarufatti (INAF-OAB) GCN Circular 36938) with telescope of Nastro Verde Observatory - Sorrento (Naples), Italy. Member of: AAVSO - American Association of Variable Star Observers. UAI/SSV - Unione Astrofili Italiani/sezione stelle variabili. AstroCampania Associazione The observations started at 19:40 UT of 2024/07/27, after about 15.35 hours after the GRB trigger, at the end of twilight, clear sky, with principal telescope SC 0.35 f/10 with focal reduced + CCD Sbig ST10 XME I took 52 image of 60 sec each. All images are unfiltered, calibrated with masterdark and masterflat,stacked with Tycho Tracker software We have not detected any clearly visible sources, up to 20th magnitude with clear skies. Start T0+ End T0+ Rlim 19:26:25 UT 20:30:16 UT 19.5 We did not found any optical counterpart in the error box of the XRTcandidate. Magnitudes were estimated with the Gaia DR2 cat. and are not corrected for galactic dust extinction. The message may be cited. View this GCN Circular online at https://gcn.nasa.gov/circulars/36964. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34827] EP-WXT trigger 01709002661 is not a real source
by GCN Circulars 28 Jul '24

28 Jul '24

TITLE: GCN CIRCULAR NUMBER: 36963 SUBJECT: EP-WXT trigger 01709002661 is not a real source DATE: 24/07/28 10:36:07 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> D.Y. Li., Q. Y. Wu (NAOC, CAS), Y. F. Liang (PMO, CAS), H. W . Pan (NAOC, CAS) on behalf of the Einstein Probe team The EP-WXT trigger 01709002661 at 05:49:10.549 UTC on 28th July 2024, is not a real source. View this GCN Circular online at https://gcn.nasa.gov/circulars/36963. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34826] GRB 240727A: NOT optical observation
by GCN Circulars 28 Jul '24

28 Jul '24

TITLE: GCN CIRCULAR NUMBER: 36962 SUBJECT: GRB 240727A: NOT optical observation DATE: 24/07/28 09:40:19 GMT FROM: Dong Xu at NAOC/CAS <dxu(a)nao.cas.cn> J. An, S.Y. Fu, S.Q. Jiang, X. Liu, Z.P. Zhu, D. Xu (NAOC), S.G. Sorensen (NOT) report on behalf of a large collaboration: We observed the field of GRB 240727A detected by Swift (Parsotan et al., GCN 36938) using the the 2.56-m Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. We obtained 6x300 s Sloan r-band images at a median time of 21:45:11.8 UT on 2024-07-27. The optical afterglow (Zheng & Filippenko, GCN 36939; Liu et al., GCN 36940; Dubay et al., GCN 36941) is clearly detected in our stacked r-band image with r = 23.4 +/- 0.1 mag, calibrated with nearby Pan-STARRS stars and not corrected for Galactic extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/36962. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34825] GRB 240727A: JinShan optical upper limits
by GCN Circulars 28 Jul '24

28 Jul '24

TITLE: GCN CIRCULAR NUMBER: 36961 SUBJECT: GRB 240727A: JinShan optical upper limits DATE: 24/07/28 09:24:29 GMT FROM: Dong Xu at NAOC/CAS <dxu(a)nao.cas.cn> J. An, S.Y. Fu, S.Q. Jiang, Z.P. Zhu, X. Liu, L.B. He, D. Xu (NAOC), J.Z. Liu (XAO) report on behalf of a large collaboration: We observed the field of GRB 240727A detected by Swift (Parsotan et al., GCN 36938) using the 100C telescope of the JinShan project located at Altay, Xinjiang, China. A series of Sloan r- and i- band frames were obtained from 15:37:37 UT to 17:13:11 UT on 2024-07-27. No source is detected at the optical afterglow position (Zheng & Filippenko, GCN 36939; Liu et al., GCN 36940; Dubay et al., GCN 36941), down to the 5-sigma upper limits of r ~ 23.0 and i ~ 21.8, calibrated with nearby PanSTARRS stars and not corrected for Galactic extinction. We acknowledge the excellent support from S.W. Luo, M.M. Yang, Z.K. Feng, Q.C. Zhao and L.F. Huo for enabling these observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/36961. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34824] GRB 240727A Bassano Bresciano Observatory upper limit
by GCN Circulars 28 Jul '24

28 Jul '24

TITLE: GCN CIRCULAR NUMBER: 36960 SUBJECT: GRB 240727A Bassano Bresciano Observatory upper limit DATE: 24/07/28 08:09:05 GMT FROM: Ulisse Quadri at Bassano Bresciano Observatory <osservatoriobassano(a)gmail.com> U.Quadri, L.Strabla and P.Madurini (Bassano Bresciano Astronomical Observatory), Members of: AAVSO - American Association of Variable Star Observers. UAI/SSV - Unione Astrofili Italiani/SSV-GRB section. GAC - Gruppo Astrofili Cremonesi. In a large collaboration with: M.G. Dainotti (National Astronomical Observatory of Japan), Y. Niino (Tokyo University, Institute of Astronomy), K. Kalinowski (Aarhus University, Department of Physics and Astronomy), B. De Simone (Universita' degli Studi Di Salerno) report: We imaged the field of GRB 240727A detected by SWIFT(trigger 1245074) with the robotic telescope of (IAU station 565) Bassano Bresciano Observatory, Italy. The observations started 19.78 hour after the GRB trigger, At the end of twilight with our Newton telescope D=450 mm F/D=4.5. Weather conditions were good. We co-added 2 series of 30 exposures of 60 sec each. Start T0+ End T0+ Vlim 19.78 hour 20.86 hour 20 We did not found any optical counterpart in the error box of the XRTcandidate. Parsotan et al.(GCN 36938), WeiKanget al.(GCN 36939), X. Liu et al.(GCN 36940). Magnitudes were estimated with the pan-STAR cat. and are not corrected for galactic dust extinction. Reference: http://www.osservatoriobassano.org/GRB.asp The message may be cited. View this GCN Circular online at https://gcn.nasa.gov/circulars/36960. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34823] GRB 240727D: Correction to the GRB name in GCN 36958
by GCN Circulars 28 Jul '24

28 Jul '24

TITLE: GCN CIRCULAR NUMBER: 36959 SUBJECT: GRB 240727D: Correction to the GRB name in GCN 36958 DATE: 24/07/28 06:05:11 GMT FROM: rachel.hamburg(a)ijclab.in2p3.fr R. Hamburg (CNRS/IN2P3/IJCLab) and S. Bala (USRA) report on behalf of the Fermi-GBM Team: "The Fermi Gamma-ray Burst Monitor (GBM) trigger 743817111 / 240727994 at 23:51:46.07 UT on 27 July 2024 was incorrectly named GRB 240727A (GCN 36958). This trigger should be named GRB 240727D. We apologize for any confusion caused." View this GCN Circular online at https://gcn.nasa.gov/circulars/36959. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34822] GRB 240727A: Fermi GBM Final Real-time Localization
by GCN Circulars 28 Jul '24

28 Jul '24

TITLE: GCN CIRCULAR NUMBER: 36958 SUBJECT: GRB 240727A: Fermi GBM Final Real-time Localization DATE: 24/07/28 00:02:26 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 23:51:46 UT on 27 Jul 2024, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 240727A (trigger 743817111.069264 / 240727994). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 115.5, Dec = -33.0 (J2000 degrees, equivalent to J2000 07h 42m, -33d 00'), with a statistical uncertainty of 6.0 degrees. The angle from the Fermi LAT boresight is 22.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240727994/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240727994/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240727994/… View this GCN Circular online at https://gcn.nasa.gov/circulars/36958. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34821] GRB 240727C: AstroSat CZTI detection of a long burst
by GCN Circulars 27 Jul '24

27 Jul '24

TITLE: GCN CIRCULAR NUMBER: 36957 SUBJECT: GRB 240727C: AstroSat CZTI detection of a long burst DATE: 24/07/27 22:57:07 GMT FROM: Gaurav Waratkar at IIT Bombay <gauravwaratkar(a)iitb.ac.in> A. Dasgupta (BITS Pilani, Hyderabad), S. Srijan (IITB), G. Waratkar (IITB), J. Joshi (IUCAA), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration: Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long-duration GRB 240727C which was also detected by INTEGRAL/SPI-ACS (Trigger 10817). The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2024-07-27 17:30:08.2 UTC. The measured peak count rate associated with the burst is 280 (+160, -1) counts/s above the background in the combined data of all quadrants, with a total of 635 (+187, -160) counts. The local mean background count rate was 338 (+4, -8) counts/s. Using cumulative rates, we measure a T90 of 7.0 (+1.0, -2.4) s. It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2024-07-27 17:30:07.7 UTC. The measured peak count rate is 376 (+63, -61) counts/s above the background in the combined Veto data of three quadrants (out of four), with a total of 1084 (+274, -282) counts. The local mean background count rate was 1079 (+7, -9) counts/s. We measure a T90 of 5.7 (+2.7, -3.0) s from the cumulative Veto light curve. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project. CZTI GRB detections are reported regularly on the payload site at: http://astrosat.iucaa.in/czti/?q=grb View this GCN Circular online at https://gcn.nasa.gov/circulars/36957. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 34820] GRB 240727A: Swift-XRT refined Analysis
by GCN Circulars 27 Jul '24

27 Jul '24

TITLE: GCN CIRCULAR NUMBER: 36956 SUBJECT: GRB 240727A: Swift-XRT refined Analysis DATE: 24/07/27 20:27:35 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> J. D. Gropp (PSU), S. Dichiara (PSU), A.P. Beardmore (U. Leicester), J.P. Osborne (U. Leicester), C. Salvaggio (INAF-OAB), M. Ferro (INAF-OAB), R. Brivio (INAF-OAB), J.A. Kennea (PSU) and P.A. Evans report on behalf of the Swift-XRT team: We have analysed 6.6 ks of XRT data for GRB 240727A, from 109 s to 51.8 ks after the BAT trigger. The data comprise 377 s in Windowed Timing (WT) mode (the first 8 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The light curve can be modelled with an initial power-law decay with an index of alpha=0.89 (+0.26, -0.58), followed by a break at T+177 s to an alpha of 1.80 (+0.06, -0.05). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.98 (+/-0.06). The best-fitting absorption column is 1.46 (+0.19, -0.18) x 10^21 cm^-2, in excess of the Galactic value of 3.6 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.25 (+0.14, -0.12) and a best-fitting absorption column consistent with the Galactic value. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 5.3 x 10^-11 (5.4 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 3.6 (+3.6, -0.0) x 10^20 cm^-2 Galactic foreground: 3.6 x 10^20 cm^-2 Excess significance: <1.6 sigma Photon index: 1.25 (+0.14, -0.12) If the light curve continues to decay with a power-law decay index of 1.80, the count rate at T+24 hours will be 4.8 x 10^-4 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.5 x 10^-14 (2.6 x 10^-14) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/01245074. This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/36956. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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