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

[vsnet-grb-info 40712] GRB 251111A: Swift-XRT afterglow detection
by GCN Circulars 12 Nov '25

12 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42648 SUBJECT: GRB 251111A: Swift-XRT afterglow detection DATE: 25/11/12 10:51:12 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> S. Campana (INAF-OAB), D.N. Burrows (PSU), S. Lanava (PSU), S. Dichiara (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A. Melandri (INAF-OAR), T. Sbarrato (INAF-OAB) and P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of GRB 251111A. We searched for X-ray sources in 2.1 ks of Photon Counting (PC) mode data. The total exposure at the position of the afterglow (see below) is 2.1 ks, obtained between T0+7.6 ks and T0+36.9 ks. An uncatalogued X-ray source is detected and is believed to be the afterglow. Using 305 s of PC mode data and 1 UVOT image, we find an enhanced XRT position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 32.36166, +5.22815 which is equivalent to: RA (J2000): 02h 09m 26.80s Dec(J2000): +05d 13' 41.3" with an uncertainty of 5.1 arcsec (radius, 90% confidence). The observed count rate was 2.5 (+1.2, -0.9)e-02 count/s at T0+7.7 ks, falling to 5.2 (+2.6, -1.9)e-03 at T0+33.8 ks, which indicates the X-ray source is fading. The results of the XRT-team automatic analysis are available at https://www.swift.ac.uk/xrt_products/03000189. The results of the full analysis of the XRT observations are available at https://www.swift.ac.uk/SVOM/SVOM_FIELD00049. This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/42648. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 40711] GRB 251111A: SVOM/VT optical observations with X-band data
by GCN Circulars 12 Nov '25

12 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42647 SUBJECT: GRB 251111A: SVOM/VT optical observations with X-band data DATE: 25/11/12 07:32:30 GMT FROM: Yinuo Ma <mayn(a)bao.ac.cn> Y. N. Ma, H. L. Li, L. P. Xin, Z. H. Yao, Y. L. Qiu, C. Wu, X. H. Han, Y. Xu, J. Wang, P. P. Zhang, W. J. Xie, Y. J. Xiao, H. B. Cai, L. Lan, J. S. Deng, J. Y. Wei (NAOC), J. Palmerio (CEA), Y. H. Cheng (SWIFAR, YNU), B. T. Wang(YNAO) report on behalf of the SVOM/VT team. SVOM/VT performed an automatic slew on the burst GRB 251111A (sb25111101) triggered by SVOM/ECLAIRs (Cheng et al., GCN 42637). SVOM/VT began observing the field at 2025-11-11 06:01:57 UTC, 51.656 minutes after T0, in the VT_B (400nm-650nm) and VT_R (650nm-1000nm) channels simultaneously. With X-band data available, the optical counterpart (López-Cámara et al., GCN 42638; Wu et al., GCN 42639; Zheng et al., GCN 42640; Wu et al., GCN 42641) was detected in VT_R band within XRT's error box (Evans et al., GCN 42645) and EP-FXT's error box (Cheng et al., GCN 42643) at the mid time of 1.34 hour, followed with a decay slope of -0.7. The measurements are: mid time (h) | exposure time (s) | band | mag (AB) -------------|-------------------|------|---------------- 1.34 | 28*50 | VT_R | 22.3+/-0.2 6.10 | 14*100 | VT_R | 23.5+/-0.3 Data analysis is on going. Our photometry was not corrected for Galactic extinction. 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. VT was jointly developed by Xi'an Institute of Optics and Precision Mechanics (XIOPM), CAS and National astronomical observatories (NAOC), CAS. View this GCN Circular online at https://gcn.nasa.gov/circulars/42647. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 40710] SVOM GRB251111.42: Global MASTER-Net observations report
by GCN Circulars 11 Nov '25

11 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42646 SUBJECT: SVOM GRB251111.42: Global MASTER-Net observations report DATE: 25/11/11 15:28:29 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 [1] located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the SVOM GRB251111.42 (trigger No 1762855221,21h 58m 08.11s , -32d 32m 58.9s, R=1) errorbox 17209 sec after notice time and 17236 sec after trigger time at 2025-11-11 14:47:37 UT, with upper limit up to 16.2 mag. Observations started at twilight. The observations began at zenith distance = 76 deg. The sun altitude is -10.6 deg. The galactic latitude b = -53 deg., longitude l = 14 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3038591 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 17327 | 2025-11-11 14:47:37 | MASTER-Kislovodsk | (21h 55m 21.98s , -32d 13m 40.7s) | C | 180 | 15.8 | 17327 | 2025-11-11 14:47:37 | MASTER-Kislovodsk | (22h 00m 17.67s , -32d 36m 56.7s) | C | 180 | 16.2 | 17468 | 2025-11-11 14:50:58 | MASTER-Kislovodsk | (22h 00m 08.74s , -32d 41m 52.6s) | C | 60 | 15.6 | 17468 | 2025-11-11 14:50:58 | MASTER-Kislovodsk | (22h 05m 05.54s , -33d 05m 13.1s) | C | 60 | 16.2 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. [1] - V.M. Lipunov, V.G. Kornilov, E.S. Gorbovskoy, N.A. Tiurina & A.S.Kuznetsov, 2023, Astronomical Robotic Networks and Operative Multichanel Astrophysics, Lomonosov MSU PRESS, 591pp. http : // www.pereplet.ru/lipunov/625.html View this GCN Circular online at https://gcn.nasa.gov/circulars/42646. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 40709] GRB 251111A: Swift-XRT observations
by GCN Circulars 11 Nov '25

11 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42645 SUBJECT: GRB 251111A: Swift-XRT observations DATE: 25/11/11 14:02:01 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> P.A. Evans (U. Leicester), J.A. Kennea (PSU), E. Ambrosi (INAF-IASFPA) , A.P. Beardmore (U. Leicester), M.G. Bernardini (INAF-OAB), R. Brivio (INAF-OAB), D.N. Burrows (PSU), S. Campana (INAF-OAB), M. Capalbi (INAF-OAR), A. D'Ai (INAF-IASFPA), P. D'Avanzo (INAF-OAB), V. D'Elia (SSDC & INAF-OAR), S. Dichiara (PSU), M. Ferro (INAF-OAB), A. Melandri (INAF-OAR), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), M. Perri (SSDC & INAF-OAR), C. Salvaggio (INAF-OAB), T. Sbarrato (INAF-OAB), B. Sbarufatti (INAF-OAB), M.A. Williams (PSU) report on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the SVOM/ECLAIRs-detected source GRB 251111A, collecting 288 s of Photon Counting (PC) mode data between T0+7.4 ks and T0+7.8 ks after the trigger. We have detected 1 source. This has been automatically classified as an uncatalogued X-ray source. Uncatalogued X-ray sources -------------------------- Source 1 (SWIFT J020926.8+051342): ================================== RA (J2000.0): 32.3618 = 02 09 26.83 Dec (J2000.0): +5.2284 = +05 13 42.2 Error: 5.7 (arcsec, radius, 90% confidence). Detect flag: GOOD Distance: 2.0 arcmin from the SVOM/ECLAIRs position. Mean rate: 0.0264 [+0.0127, -0.0096] ct s^-1 Mean flux: (7.2 [+3.5, -2.6])e-13 erg cm^-2 s^-1 Peak rate: 0.0264 [+0.0127, -0.0096] ct s^-1 Peak flux: (7.2 [+3.5, -2.6])e-13 erg cm^-2 s^-1 ECF: 2.73e-11 erg cm^-2 ct^-1 assuming NH=5.07e+20 cm^-2, gamma=2.63 determined from a spectral fit. XMM UL: 2.6e-12 erg cm^-2 s^-1, (0.3-10 keV) so the source is not above this 3-sigma upper limit. There is no evidence for fading. The XRT position is consistent the optical counterpart reported by the SVOM/COLIBRÍ (FM-GFT; López-Cámara et al., GCN Circ. 42638), LCO 1m (Wu et al., GCN Circ. 42639) and SVOM/VT (Wu et al., GCN 42641) telescopes, as well as the Einstein Probe FXT X-ray detection (Cheng et al. 42643). All fluxes are 0.3-10 keV, observed. For all flux conversions and comparisons with catalogues and upper limits from other missions, we assumed a power-law spectrum with NH=3x10^20 cm^-2 and photon index (Gamma)=1.7 unless otherwise stated. The results of the XRT-team automatic analysis of the XRT observations, including a position-specific upper limit calculator, are available at https://www.swift.ac.uk/SVOM/SVOM_FIELD00049. This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/42645. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 40708] SVOM GRB251111.22: Global MASTER-Net observations report
by GCN Circulars 11 Nov '25

11 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42644 SUBJECT: SVOM GRB251111.22: Global MASTER-Net observations report DATE: 25/11/11 13:28:25 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-Tunka robotic telescope [1] located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the SVOM GRB251111.22 (trigger No 1762837816,02h 09m 30.79s , +05d 15m 24.1s, R=0.1259) errorbox 28018 sec after notice time and 28619 sec after trigger time at 2025-11-11 13:07:15 UT, with upper limit up to 19.9 mag. The observations began at zenith distance = 58 deg. The sun altitude is -34.8 deg. The galactic latitude b = -52 deg., longitude l = 157 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3038098 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 28650 | 2025-11-11 13:07:15 | MASTER- | (02h 09m 32.85s , +04d 36m 16.3s) | C | 60 | 19.8 | 28650 | 2025-11-11 13:07:15 | MASTER-Tunka | (02h 09m 14.02s , +04d 42m 25.1s) | C | 60 | 19.9 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. [1] - V.M. Lipunov, V.G. Kornilov, E.S. Gorbovskoy, N.A. Tiurina & A.S.Kuznetsov, 2023, Astronomical Robotic Networks and Operative Multichanel Astrophysics, Lomonosov MSU PRESS, 591pp. http : // www.pereplet.ru/lipunov/625.html View this GCN Circular online at https://gcn.nasa.gov/circulars/42644. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 40707] GRB 251111A: EP-FXT counterpart detection
by GCN Circulars 11 Nov '25

11 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42643 SUBJECT: GRB 251111A: EP-FXT counterpart detection DATE: 25/11/11 13:12:22 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> Y.H. Cheng (SWIFAR,YNU), Z. M. Wang (BNU), Y. J. Zhang (THU), C. L. Guo, J. W. Hu, Y. Liu (NAO, CAS) on behalf of the Einstein Probe (EP) team: EP-FXT performed a follow-up observation of the SVOM/ECLAIRs-detected burst GRB 251111A (SVOM/sb25111101, Cheng et al., GCN #42637) at 2025-11-11 06:06:55 (UTC), about 0.93 hours after the SVOM/ECLAIRs trigger, with an exposure time of 1939 s. One uncatalogued source is detected within the ECLAIRs error circle, and the source is spatially consistent with the counterpart reported in optical band (López-Cámara et al., GCN #42638; Wu et al., GCN #42639, Zheng et al., GCN #42640, Wu et al., GCN #42641). Preliminary analysis on this source is automatically conducted, and the details are listed as follows. Source 1 ：EPF_J020926.9+051342 RA (J2000): 32.362 Dec (J2000): 5.228 Flux: 1.24 x 10^-12 erg/s/cm2 (observed, 0.5-10 keV) Flux_err: 3.53 x 10^-13 erg/s/cm2 (1 sigma) The position uncertainty of the source is about 10 arcsec in radius (90% C.L. statistical and systematic). Launched on January 9, 2024, EP is a space X-ray observatory to monitor the soft X-ray sky with X-ray follow-up capability (Yuan et al. 2022, Handbook of X-ray and Gamma-ray Astrophysics). View this GCN Circular online at https://gcn.nasa.gov/circulars/42643. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 40706] GRB 251013C: Chandra X-ray observations and jet break detection
by GCN Circulars 11 Nov '25

11 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42642 SUBJECT: GRB 251013C: Chandra X-ray observations and jet break detection DATE: 25/11/11 10:50:45 GMT FROM: Antonio Martin-Carrillo at UCD,Space Science Group <antonio.martin-carrillo(a)ucd.ie> A. Martin-Carrillo (UCD), B. P. Gompertz (Birmingham), D. B. Malesani (DAWN/NBI and Radboud), report on behalf of a larger collaboration: We observed the afterglow of GRB 251013C (Fermi GBM team, GCN 42221; Rakotondrainibe et al., GCN 42222) with the Chandra X-ray Observatory starting on 2025-11-09 at 03:09:42 UT (i.e., T0+27.396 d, observer frame), for a total of 40 ks exposure, in response to our DDT request (PI A. Martin-Carrillo, ObsID 31983). A faint X-ray source is detected at a location consistent with that of the afterglow (Palmerio et al., GCN 42223; Laskar et al., GCN 42243). Assuming a spectrum model consistent with the one measured by Swift/XRT (Evans et al., GCN 42232; https://www.swift.ac.uk/xrt_spectra/03000137/) we infer a flux in the 0.3-10 keV energy range of ~2.5e-15 erg s^-1 cm^-2. This late Chandra observation implies that the source has undergone significant steepening in its X-ray flux decay when compared with the earlier Swift/XRT and EP/FXT observations (Evans et al., GCN 42232; Wang et al., GCN 42247), suggesting a jet break sometime between 6 and 10 days since trigger in the observer frame. We thank the entire CXO team for the rapid evaluation and scheduling of our observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/42642. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 40705] GRB 251111A: SVOM/VT optical observations with VHF data
by GCN Circulars 11 Nov '25

11 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42641 SUBJECT: GRB 251111A: SVOM/VT optical observations with VHF data DATE: 25/11/11 09:01:37 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> C. Wu (NAOC), J. T. Palmerio (CEA), L.P. Xin (NAOC), H.L. Li, Y. L. Qiu, Yehao Cheng (SWIFAR,YNU), Boting Wang(YNAO) report on behalf of the SVOM team. SVOM/VT performed an automatic slew on the burst of GRB 251111A (sb25111101) triggered by SVOM/ECLAIRs (Cheng et al. GCN 42637). SVOM/VT began observing the field automatically at 2025-11-11T06:01:57 UTC, 51.65 minutes after the T0, with the slew of the platform triggered on-board, in VT_B (400nm-650nm) and VT_R (650nm-1000nm) channels simultaneously. We confirm the detection of the source reported by López-Cámara et al. (GCN 42638) and Wu et al. (GCN 42639) in the VT_R band with the downlinked VHF data. The AB magnitude was derived as follows: -------------------------------------------- (T-T0)_mid exptime band mag 54.15 min 300 sec VT_R 21.32 +/-0.11 No correction for Galactic extinction was applied to the photometry. This result is consistent with the report by Zheng et al. (GCN 42640) 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. VT was jointly developed by Xi'an Institute of Optics and Precision Mechanics (XIOPM), CAS and National astronomical observatories (NAOC), CAS. View this GCN Circular online at https://gcn.nasa.gov/circulars/42641. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 40704] GRB 251111A: KAIT optical upper limit
by GCN Circulars 11 Nov '25

11 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42640 SUBJECT: GRB 251111A: KAIT optical upper limit DATE: 25/11/11 08:13:13 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, automatically responded to the SVOM GRB 251111A (Cheng et al., GCN 42637) starting at 05:12:13, 115 seconds after the burst. Observations were performed in 3 x 3 tiling mode, and a set of clear (roughly R) filter images were obtained. The first image covered the reported afterglow (López-Cámara et al., GCN 42638; Wu et al., GCN 42639) position was at 05:14:50, 272 seconds after the burst. We did not detect the afterglow in our clear images with the following upper limit: mid t-t0(s) exp(s) UL(mag) --------------------------- 282 20 >18.5 561 20 >18.5 763 20 >18.5 1042 20 >18.5 1323 20 >18.5 1690 40 >19.0 2156 40 >19.0 2613 40 >19.0 3168 60 >19.5 3813 60 >19.5 4442 60 >19.5 View this GCN Circular online at https://gcn.nasa.gov/circulars/42640. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 40703] GRB 251111A: LCO optical observation
by GCN Circulars 11 Nov '25

11 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42639 SUBJECT: GRB 251111A: LCO optical observation DATE: 25/11/11 07:59:03 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> C. Wu (NAOC), L. P. Xin, Xuhui Han, J. T. Palmerio (CEA/Irfu), D. Turpin, A. Saccardi, B. Cordier report on behalf of the SVOM mission team: We observed the field of GRB 251111A (SVOM/ECLAIRs, Cheng et al. GCN 42637) with the LCO 1m telescope at Cerro Tololo Inter-American Observatory equipped with the Sinistro instrument. Our observation started at 2025-11-11T05:31:30.632 about 21.21 minutes after the SVOM/ECLAIRs T0 time. We obtained a sequence of 3x200 s exposures in the SDSS r band. The optical counterpart reported by SVOM/COLIBRÍ (FM-GFT) (López-Cámara et al., GCN 42638) is clearly detected in our stacked image. We measure an AB magnitude of r = 21.52 ± 0.15 at a midtime of Tmid − T0 = 26.63 min after the trigger. The photometry was calibrated against nearby Pan-STARRS1 stars and no correction for Galactic dust extinction was applied. This project is funded by the SVOM collaboration. View this GCN Circular online at https://gcn.nasa.gov/circulars/42639. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0