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

[vsnet-grb-info 35195] GRB 240825A: Fermi GBM Observation
by GCN Circulars 26 Aug '24

26 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37301 SUBJECT: GRB 240825A: Fermi GBM Observation DATE: 24/08/26 16:12:52 GMT FROM: Vidushi Sharma at NASA GSFC/UMBC <vidushi.sharma(a)nasa.gov> V. Sharma (NASA GSFC/UMBC), and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team: At 15:53:00 UT on 25 August 2024, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 240825A (trigger 746293985/240825662), which was also detected Swift (R. Gupta et al. 2024, GCN 37274), Fermi-LAT (N. Di Lalla et al. 2024, GCN 37288), and VLT/X-shooter (A. Martin-Carrillo et al. 2024, GCN 37293). The Final Real-time Localization (Fermi GBM Team 2024, GCN 37273) is consistent with Swift and Fermi-LAT. The angle from the Fermi LAT boresight is 52 degrees. The GBM light curve many overlapping short pulses with a duration (T90) of about 4 s (50-300 keV). The time-averaged spectrum from T0+0.96 to T0+6.85 s best fit by a Band function with Epeak = 442 +/- 8 keV, alpha = -0.82 +/- 0.01, and beta = -2.22 +/- 0.02. The event fluence (10-1000 keV) in this time interval is (1.01 +/- 0.01)E-04 erg/cm^2. The 1-s peak photon flux measured starting from T0+1.22 s in the 10-1000 keV band is 203 +/- 1 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/" View this GCN Circular online at https://gcn.nasa.gov/circulars/37301. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35194] GRB 240825A: Fermi GBM Observation
by GCN Circulars 26 Aug '24

26 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37301 SUBJECT: GRB 240825A: Fermi GBM Observation DATE: 24/08/26 16:12:52 GMT FROM: Vidushi Sharma at NASA GSFC/UMBC <vidushi.sharma(a)nasa.gov> V. Sharma (NASA GSFC/UMBC), and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team: At 15:53:00 UT on 25 August 2024, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 240825A (trigger 746293985/240825662), which was also detected Swift (R. Gupta et al. 2024, GCN 37274), Fermi-LAT (N. Di Lalla et al. 2024, GCN 37288), and VLT/X-shooter (A. Martin-Carrillo et al. 2024, GCN 37293). The Final Real-time Localization (Fermi GBM Team 2024, GCN 37273) is consistent with Swift and Fermi-LAT. The angle from the Fermi LAT boresight is 52 degrees. The GBM light curve many overlapping short pulses with a duration (T90) of about 4 s (50-300 keV). The time-averaged spectrum from T0+0.96 to T0+6.85 s best fit by a Band function with Epeak = 442 +/- 8 keV, alpha = -0.82 +/- 0.01, and beta = -2.22 +/- 0.02. The event fluence (10-1000 keV) in this time interval is (1.01 +/- 0.01)E-04 erg/cm^2. The 1-s peak photon flux measured starting from T0+1.22 s in the 10-1000 keV band is 203 +/- 1 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/" View this GCN Circular online at https://gcn.nasa.gov/circulars/37301. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35193] GRB 240825A : MISTRAL/T193 OHP optical follow-up of the afterglow
by GCN Circulars 26 Aug '24

26 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37300 SUBJECT: GRB 240825A : MISTRAL/T193 OHP optical follow-up of the afterglow DATE: 24/08/26 15:52:26 GMT FROM: Emeric Le Floc'h at CEA-Saclay <emeric.lefloch(a)cea.fr> E. Le Floc’h (CEA Paris-Saclay, DAp/AIM), C. Adami (LAM), B. Schneider (MIT), A. Saccardi (GEPI, Obs. De Paris), S. Basa (OSU Pytheas, LAM), M. Dennefeld (IAP), F. Schüssler (CEA Paris-Saclay, DPhP), report on behalf of the MISTRAL GRB collaboration : We observed the field of GRB 240825A (Gupta et al., GCN 37274; Fermi GBM team, GCN 37273) with the MISTRAL instrument mounted on the 193cm telescope at Observatoire de Haute-Provence (France). Three exposures of 5min were obtained in the SDSS r’ band, for a total exposure time of 15min and an observation mid-time of 2024 August 25, ~22:40 UT (~6.85 hr after the GRB trigger). The optical afterglow is clearly detected, at a position consistent with the counterpart reported earlier by other telescopes (e.g., Jiang et al., GCN 37275; Dutton et al., GCN 37276; Odeh et al., GCN 37277, Li et al., GCN 37280, Izzo et al., GCN 37287; Lipunov et al. GCN.37289; Leonini et al. GCN 37291; Wu et al., GCN 37292; Martin-Carrillo et al., GCN 37293; Brivio et al., GCN 37295; Odeh, GCN 37299). We obtain a magnitude of r’ = 20.63 +/- 0.03 mag (AB), calibrated against nearby stars from the Pan-STARRS catalog, and where the photometric uncertainty does not include any systematics. The photometry is not corrected for Galactic extinction. We are grateful to Xavier Delfosse (IPAG) and we also thank the support from the Observatoire de Haute-Provence, in particular Jean-Pierre Troncin and Jérome Schmitt. View this GCN Circular online at https://gcn.nasa.gov/circulars/37300. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35192] GRB 240825A: AKO Optical Follow-Up Observations
by GCN Circulars 26 Aug '24

26 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37299 SUBJECT: GRB 240825A: AKO Optical Follow-Up Observations DATE: 24/08/26 15:40:54 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 Nidhal Guessoum (American University of Sharjah, UAE), report: We followed up our observations (Odeh & Guessoum, GCN 37277) of GRB 240825A (Fermi GBM team, GCN 37273; Gupta et al., GCN 37274; Swift-XRT team, GCN 37290), with our 0.36m f/7.7 robotic telescope, performing 5 observations between 25 August 2024 at 16:48 UT (0.92 hour after the trigger) and 25 August 2024 at 18:57 UT (3.1 hours after the trigger). We obtained multiple 180-sec exposures in Ic filter. The optical afterglow was fading: Our measurements are consistent with other reports (Jiang et al., GCN 37275; Lipunov et al., GCN 37279; and Wei et al., GCN 37292). The following magnitudes were determined using the Atlas catalogue as a reference: ---------------------------------------------------------------------------- ObsTime (mid), t-T0 (hour), Exposure (sec), Filter, Mag & Mag_Err ---------------------------------------------------------------------------- 2024-08-25T16:59Z, 1.1, 7x180s (stacked), Ic, 17.3 +/- 0.15 2024-08-25T17:23Z, 1.5, 7x180s (stacked), Ic, 17.9 +/- 0.18 2024-08-25T17:48Z, 1.9, 7x180s (stacked), Ic, 18.1 +/- 0.13 2024-08-25T18:17Z, 2.4, 7x180s (stacked), Ic, 18.2 +/- 0.13 2024-08-25T18:42Z, 2.8, 7x180s (stacked), Ic, 18.4 +/- 0.17 ---------------------------------------------------------------------------- The magnitudes were not corrected for galactic extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/37299. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35191] GRB 240825A: AstroSat CZTI detection of the long bright burst
by GCN Circulars 26 Aug '24

26 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37298 SUBJECT: GRB 240825A: AstroSat CZTI detection of the long bright burst DATE: 24/08/26 15:39:53 GMT FROM: Gaurav Waratkar at IIT Bombay <gauravwaratkar(a)iitb.ac.in> J. Joshi (IUCAA), G. Waratkar (IITB), 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 bright long-duration GRB 240825A which was also detected by Fermi/GBM (Fermi GBM team, GCN Circ. 37273), Swift/BAT (R. Gupta et al., GCN Circ. 37274), and INTEGRAL/SPI-ACS (Trigger 10871). The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2024-08-25 15:53:01.50 UTC. Due to the extremely bright nature of the GRB, all four quadrants of CZT detectors were saturated. This affects the total counts and peak counts reported. The measured peak count rate associated with the burst is 2791 (+90, -96) counts/s above the background in the combined data of three quadrants (out of four), with a total of 6260 (+168, -178) counts. The local mean background count rate was 251 (+3, -3) counts/s. Using cumulative rates, we measure a T90 of 6.2 (+0.9, -0.8) s. In the preliminary analysis, we find 600 Compton events associated with this event. The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2024-08-25 15:53:01.57 UTC. The measured peak count rate associated with the burst is 9409 (+168, -183) counts/s above the background in the combined data of all quadrants, with a total of 24203 (+406, -428) counts. The local mean background count rate was 1473 (+7, -9) counts/s. We measure a T90 of 6.1 (+0.7, -0.6) 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/37298. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35190] SGR 1E 1841-045 / Kes 73: SVOM/GRM observation
by GCN Circulars 26 Aug '24

26 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37297 SUBJECT: SGR 1E 1841-045 / Kes 73: SVOM/GRM observation DATE: 24/08/26 14:05:15 GMT FROM: Chenwei Wang at IHEP <cwwang(a)ihep.ac.cn> SVOM/GRM team: Chen-Wei Wang, Yong-Wei Dong, Jiang-Tao Liu, Shi-Jie Zheng, Jian-Chao Sun, Wen-Jun Tan, Jiang He, Min Gao, Hao-Xuan Guo, Yue Huang, Lu Li, Yong-Ye Li, Hong-Wei Liu, Xin Liu, Hao-Li Shi, Li-Ming Song, You-Li Tuo, Hao-Xi Wang, Jin Wang, Jin-Zhou Wang, Ping Wang, Rui-Jie Wang, Yu-Xi Wang, Bo-Bing Wu, Shao-Lin Xiong, Jian-Ying Ye, Yi-Tao Yin, Wen-Hui Yu, Fan Zhang, Li Zhang, Peng Zhang, Shuang-Nan Zhang, Wen-Long Zhang, Yan-Ting Zhang, Shu-Min Zhao, Xiao-Yun Zhao, Chao Zheng (IHEP), Maria-Grazia Bernardini (LUPM/INAF-OAB), Laurent Bouchet (IRAP), David Corre (CEA), Tais Maiolino (LUPM), Frédéric Piron (LUPM), Stéphane Schanne (CEA), Jingwei Wang (IAP) SVOM JSWG: Jian-Yan Wei (NAOC), Bertrand Cordier (CEA), Shuang-Nan Zhang (IHEP), Stéphane Basa (LAM), JeanLuc Attéia (IRAP), Arnaud Claret (CEA), Zi-Gao Dai (USTC), Frédéric Daigne (IAP), Jin-Song Deng (NAOC), Andrea Goldwurm (APC), Diego Götz (CEA), Xu-Hui Han (NAOC), Cyril Lachaud (APC), En-Wei Liang (GXU), Yu-Lei Qiu (NAOC), Susanna Vergani (Obs.Paris), Jing Wang (NAOC), Chao Wu (NAOC), Li-Ping Xin (NAOC), Bing Zhang (UNLV) report on behalf of the SVOM team: During the commissioning phase, the SVOM/GRM detected two bursts probably from SGR 1E 1841-045 / Kes 73, one from in-flight trigger and the other from ground search of the data. Here is the list of these bursts: TrigTime (UTC) (1)2024-08-22T11:00:56.800 (SVOM trigger reference: sb24082202). The GRM light curve of this burst can be found here: https://www.bursthub.cn/admin/static/tn240822_110056.png (2)2024-08-21T20:29:24.450, which was also reported by Swift (GCN 37222), Fermi/GBM (GCN 37234) and GECAM-B (GCN 37240). The GRM light curve of this burst can be found here: https://www.bursthub.cn/admin/static/tn240821_202924.png The SVOM/GRM locations of these two bursts are consistent with SGR 1E 1841-045 / Kes 73. At the time of both bursts ECLAIRs was in operational mode and the source 1E 1841-045 was outside of the ECLAIRs field of view. The Space Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA, China), National Center for Space Studies (CNES, France) and the Chinese Academy of Sciences (CAS, China), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. GRM is developed by the Institute of High Energy Physics (IHEP) of CAS. The SVOM/GRM point of contact for this burst is: Chen-Wei Wang (IHEP)(cwwang(a)ihep.ac.cn) View this GCN Circular online at https://gcn.nasa.gov/circulars/37297. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35189] GRB 240825A: Swift/UVOT Detection
by GCN Circulars 26 Aug '24

26 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37296 SUBJECT: GRB 240825A: Swift/UVOT Detection DATE: 24/08/26 12:54:52 GMT FROM: Paul Kuin at MSSL <npkuin(a)gmail.com> N. P. M. Kuin (UCL-MSSL) and Gupta (NASA GSFC) report on behalf of the Swift/UVOT team:The Swift/UVOT began settled observations of the field of GRB 240825A 93 s after the BAT trigger (Gupta et al., GCN Circ. 37274). A source consistent with the XRT position (Evans et al. GCN Circ. 37290 is detected in the initial UVOT exposures. The preliminary UVOT position is: RA (J2000) = 22:58:17.26 = 344.57192 (deg.) Dec (J2000) = +01:01:36.9 = 1.02691 (deg.) with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence). Preliminary detections using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white 93 243 147 15.58 +/- 0.02 v 807 827 20 17.02 +/- 0.20 b 561 580 20 17.54 +/- 0.15 u 305 555 246 16.93 +/- 0.05 w1 684 1281 58 18.55 +/- 0.30 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.063 in the direction of the burst (Schlegel et al. 1998). View this GCN Circular online at https://gcn.nasa.gov/circulars/37296. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35188] GRB 240825A: REM detection of the optical/NIR afterglow
by GCN Circulars 26 Aug '24

26 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37295 SUBJECT: GRB 240825A: REM detection of the optical/NIR afterglow DATE: 24/08/26 12:03:35 GMT FROM: Riccardo Brivio <riccardo.brivio(a)inaf.it> R. Brivio, M. Ferro, P. D'Avanzo, S. Covino, D. Fugazza (INAF-OAB) report on behalf of the REM team: We observed the field of GRB 240825A (Gupta et al., GCN 37274; Fermi GBM team, GCN 37273; Di Lalla et al., GCN 37288) with the REM 60cm robotic telescope located at the ESO observatory of La Silla (Chile). The observations were carried in the g, r, i, z, J, H and K bands, starting on 2024 Aug 26 at 00:28:43 UT (i.e. about 8.6 hours after the Swift trigger) and lasted for about 1 hour. The optical afterglow is detected in the r band at a position coincident with that reported by Swift-UVOT (Gupta et al., GCN 37274) and other optical observations (Jian et al., GCN 37275; Dutton et al., GCN 37276; Odeh et al., GCN 37277; Zhang et al., GCN 37278; Li et al., GCN 37280; Izzo & Malesani, GCN 37287). The NIR afterglow is detected in the J band at a position consistent with the optical counterpart. From preliminary photometry, we derive the following magnitudes: r = 20.5 +/- 0.3 (AB; calibrated against the Pan-STARRS catalogue) at a mid-time of t-t0 ~ 9.1 hours after the trigger, J = 17.7 +/- 0.3 (Vega; calibrated against the 2MASS catalogue) at a mid-time of t-t0 ~ 9.2 hours after the trigger. View this GCN Circular online at https://gcn.nasa.gov/circulars/37295. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35187] GRB 240825A: Swift-XRT refined Analysis
by GCN Circulars 26 Aug '24

26 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37294 SUBJECT: GRB 240825A: Swift-XRT refined Analysis DATE: 24/08/26 10:43:16 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> J. D. Gropp (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), M. Perri (SSDC & INAF-OAR), V. D'Elia (SSDC & INAF-OAR), B. Sbarufatti (INAF-OAB), S. Dichiara (PSU), J.A. Kennea (PSU) and P.A. Evans report on behalf of the Swift-XRT team: We have analysed 8.6 ks of XRT data for GRB 240825A, from 71 s to 56.6 ks after the BAT trigger. The data comprise 1.2 ks in Windowed Timing (WT) mode (the first 10 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The light curve can be modelled with a series of power-law decays. The initial decay index is alpha=3.13 (+0.24, -0.21). At T+119 s the decay flattens to an alpha of 0.83 (+/-0.06). The light curve breaks again at T+406 s to a decay with alpha=1.121 (+0.019, -0.028), and again at T+1288 s s to alpha=1.52 (+6.48, -0.05), before a final break at T+6251 s s after which the decay index is 1.25 (+0.06, -0.08). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.661 (+/-0.017). The best-fitting absorption column is 1.09 (+/-0.04) x 10^22 cm^-2, at a redshift of 0.659, in addition to the Galactic value of 5.3 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.76 (+/-0.09) and a best-fitting absorption column of 9.1 (+1.6, -1.4) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 4.4 x 10^-11 (5.9 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Galactic foreground: 5.3 x 10^20 cm^-2 Intrinsic column: 9.1 (+1.6, -1.4) x 10^21 cm^-2 at z=0.659 Photon index: 1.76 (+/-0.09) If the light curve continues to decay with a power-law decay index of 1.25, the count rate at T+24 hours will be 0.093 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 4.1 x 10^-12 (5.5 x 10^-12) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/01250617. This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/37294. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 35186] GRB 240825A: VLT/X-shooter redshift
by GCN Circulars 26 Aug '24

26 Aug '24

TITLE: GCN CIRCULAR NUMBER: 37293 SUBJECT: GRB 240825A: VLT/X-shooter redshift DATE: 24/08/26 08:44:45 GMT FROM: Antonio Martin-Carrillo at UCD,Space Science Group <antonio.martin-carrillo(a)ucd.ie> A. Martin-Carrillo (UCD), B. Schneider (MIT), G. Pugliese (API-UvA), L. Izzo (INAF-OACn & DARK/NBI), D. B. Malesani (DAWN/NBI and Radboud Univ.), A. Saccardi (GEPI/Obs. de Paris), T. Laskar (Utah), J. F. Agui Fernandez (CAHA) and S. D. Vergani (GEPI/Obs. de Paris) report on behalf of the Stargate collaboration: We observed the optical counterpart of the Swift/Fermi GRB 240825A (Gupta et al., GCN 37274; Fermi GBM team, GCN 37273; Di Lalla et al., GCN 37288) using the ESO VLT UT3 (Melipal) equipped with the X-shooter spectrograph. Our spectra cover the wavelength range 3000-21000 AA, and consist of 4 exposures of 1200 s each. The observation was carried out under good seeing (1”) with mid-time 03:03:55 UT on 2024 August 26 (~11.2 hours after the Swift trigger). In a 60 s image taken with the acquisition camera, we clearly detect the optical afterglow (Gupta et al., GCN 37274; Jiang et al. GCN 37275; Dutton et al. GCN 37276; Odeh et al. GCN 37277; Zhang et al. GCN 37278; Li et al. GCN 37280; Izzo & Malesani, GCN 37287; Lipunov et al. GCN 37289; Leonini et al. GCN 37291; Wu et al. GCN 37292), for which we measure an AB magnitude r = 20.8 (calibrated against nearby stars from the Pan-STARRS catalogue). In a preliminary reduction of the spectra, we clearly detect the continuum over the entire wavelength range. From detection of multiple absorption features, which we interpret as due to Fe II, Fe II*, Mn II, Mg II, Mg I, Ca II and Na I, we infer a common redshift of z = 0.659. We also detect bright emission lines ([O II] and [O III] doublets, Halpha and Hbeta) at a consistent redshift, which we interpret as being due to the GRB host galaxy (Izzo & Malesani, GCN 37287). We conclude that GRB 240825A is at z = 0.659. We acknowledge expert support from the ESO staff in Paranal, in particular Matias Jones. View this GCN Circular online at https://gcn.nasa.gov/circulars/37293. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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