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

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[vsnet-grb-info 42770] GRB 260515A: EP-FXT follow-up observation
by GCN Circulars 16 May '26

16 May '26
TITLE: GCN CIRCULAR NUMBER: 44642 SUBJECT: GRB 260515A: EP-FXT follow-up observation DATE: 26/05/16 09:39:53 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> Z.M. Wang (BNU), X.X. Sun(NAO, CAS), Y.H.Cheng (SWIFAR, YNU), Y. Liu (NAO, CAS) on behalf of the Einstein Probe (EP) team: EP-FXT performed an automatic follow-up observation of GRB 260515A detected by SVOM/ECLAIRs (SVOM/sb26051504, Brunet et al., GCN 44622). The follow-up obervation started at 2026-05-15T20:51:27 UTC, approximately 1.7 hours after the SVOM trigger, with a total exposure time of 5.9 ks. On-ground analysis of the FXT data found an uncatalogued fading source within the ECLAIRs error circle at R.A., Dec. = 227.6846, 24.5566 deg (J2000) with an uncertainty of about 10 arcsec (radius, 90% C.L. statistical and systematic). This position is consistent with the optical counterpart (He et al., GCN 44623; Saccardi et al., GCN 44624; Sosnovskij et al., GCN 44625; He et al., GCN 44626; Wu et al., GCN 44628; Dennefeld et al., GCN 44633; Li et al., GCN 44634). The average FXT 0.3-10 keV spectrum can be fitted with an absorbed power-law model, with the hydrogen column density fixed at the Galactic value of 3.47×10^20 cm^-2 and a photon index of 1.71(-0.09/+0.09). The derived average unabsorbed flux in the 0.3-10 keV band is 7.13(-0.19/+0.21) x 10^(-12) erg/s/cm^2. 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/44642. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 42769] EP260514a: refined analysis of the EP-WXT and follow-up EP-FXT observations
by GCN Circulars 16 May '26

16 May '26
TITLE: GCN CIRCULAR NUMBER: 44641 SUBJECT: EP260514a: refined analysis of the EP-WXT and follow-up EP-FXT observations DATE: 26/05/16 08:08:24 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> Y.-H. Cheng (SWIFAR, YNU), K.R. Ni (CCNU), R.-Z. Li (YNAO, CAS) and W.-D. Zhang (NAO, CAS) on behalf of the Einstein Probe (EP) team: The X-ray transient EP260514a was detected by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission (Cheng et al., GCN 44613) at 2026-05-14T16:56:06 (UTC). The average WXT 0.5-4 keV spectrum can be fitted with an absorbed power law with a fixed Galactic hydrogen column density of 1.49 × 10^20 cm^-2, and a photon index of 1.32 (+/-0.22). The derived average unabsorbed 0.5-4 keV flux is 4.24 (+0.70/-0.60) × 10^(-10) erg/s/cm^2. Follow-up observation by the Follow-up X-ray Telescope (FXT) on board EP was performed at 2026-05-15 08:20:00(UTC), ~15.5 hours after the WXT detection. The exposure time of the observation is around 5 ks. The on-ground analysis of the FXT data found an uncatalogued source at R.A. = 214.2955 deg, DEC = 49.3733 deg (J2000) with an uncertainty of 10 arcsec (radius, 90% C.L. statistical and systematic). The average FXT 0.5-10 keV spectra can be fitted with an absorbed power-law with a fixed hydrogen column density of 1.49 × 10^20 cm^-2 and a photon index of 1.28 (+0.76/-0.67). The derived average unabsorbed 0.5-10 keV flux is 2.28 (-0.55/+1.17) × 10^(-13) erg/s/cm^2. The uncertainties are at the 90% confidence level for the above parameters. The optical observations of EP260514a were reported by Lipunov et al. (GCN 44614), Mohan et al. (GCN 44619), Sánchez et al. (GCN 44632) and Li et al. (GCN 44638), Liu et al.,(GCN 44639) and Liu et al.,(GCN 44640). 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/44641. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 42768] EP260514a: NOT optical counterpart confirmation
by GCN Circulars 16 May '26

16 May '26
TITLE: GCN CIRCULAR NUMBER: 44640 SUBJECT: EP260514a: NOT optical counterpart confirmation DATE: 26/05/16 07:51:09 GMT FROM: liuxing(a)nao.cas.cn X. Liu, Z.P. Zhu, J. An, S.Q. Jiang, L.B. He, D. Xu (NAOC), S.Y. Fu (HUST), J.P.U. Fynbo (DAWN/NBI), L. Fuglsang, A. S. Martensson(NOT)report: We observed the field of EP260514a detected by EP/WXT (Cheng et al., GCN 44613; Lipunov et al., GCN 44614; Mohan et al., GCN 44619; Sánchez et al., GCN 44632; Li et al., GCN 44638; Liu et al., GCN 44639) using the 2.56m Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. Observation started at 2026-05-15 23:05:35 UT, i.e., about 1.26 days post-burst, and 4x300s r-band frames were obtained. The optical counterpart candidate (Liu et al., GCN 44639) has decayed to r = 23.1 +/- 0.1 in our stacked image at a median time of 1.26 days post-trigger, calibrated with Pan-STARRS DR2 stars in the field and not corrected for Galactic extinction. Its coordinares are improved as R.A.(J2000)= 14:17:10.49 Dec.(J2000)= +49:22:31.4 with an uncertainty of ~0.5 arcsec. No optical source could be detected in the Legacy DR10 image at the corresponding coordinates, down to a limiting magnitude of r ~ 24.3. We thus think the source is likely the optical counterpart of EP260514a. View this GCN Circular online at https://gcn.nasa.gov/circulars/44640. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 42767] EP260514a: TRT optical counterpart candidate
by GCN Circulars 16 May '26

16 May '26
TITLE: GCN CIRCULAR NUMBER: 44639 SUBJECT: EP260514a: TRT optical counterpart candidate DATE: 26/05/16 07:39:15 GMT FROM: liuxing(a)nao.cas.cn X. Liu, (NAOC), S. Tinyanont, R. Anutarawiramkul, P. Butpan, K. Noysena, K. Chanchaiworawit (NARIT), S.Q. Jiang, J. An, Z.P. Zhu, L.B. He, D. Xu, Z. Fan, W.X. Li, N.C. Sun (NAOC), S.Y. Fu (HUST) report: We observed the field of EP260514a dtected by EP/WXT (Cheng et al., GCN 44613), using the 0.7-m telescope of the Thai Robotic Telescope network (TRT), located at Fresno, California, U.S.A (SRO). Observation started at 2026-05-15 04:25:07 UT, i.e., 0.48 day post-burst, and 6x300 s R-band frames were obtained. Image subtraction using Legacy-DR10 reveals an uncatalogued optical source within the EP/WXT (Cheng et al., GCN 44613) error circle at coordinates R.A. (J2000) = 14:17:10.41 Dec. (J2000) = +49:22:30.9 with an uncertainty of ~ 1.5 arcsec. The source had R ~ 21.8 mag with SNR of ~3 at a median time of 11.74 hrs post-trigger, calibrated with Pan-STARRS DR2 converted using Lupton (2005) equations and not corrected for Galactic extinction. No NEO would be at the above position at the observational time by checking MPC. We think the source could be the optical cointerpart of EP260514a. View this GCN Circular online at https://gcn.nasa.gov/circulars/44639. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 42766] EP260514a: SVOM/VT optical candidate
by GCN Circulars 16 May '26

16 May '26
TITLE: GCN CIRCULAR NUMBER: 44638 SUBJECT: EP260514a: SVOM/VT optical candidate DATE: 26/05/16 06:59:29 GMT FROM: Huali Li at at NAOC, SVOM <lhl(a)nao.cas.cn> H. L. Li, Y. L. Qiu, C. Wu, L. P. Xin, Y. N. Ma, Z. H. Yao, J. R. Xu, X. H. Han, J. Wang, Y. Xu, P. P. Zhang, W. J. Xie, Y. J. Xiao, H. B. Cai, L. Lan, J. S. Deng, J. Y. Wei (NAOC) and J. Palmerio report on behalf of the SVOM/VT team. SVOM/VT performed ToO observations to the field of EP260514a (Lipunov et al., GCN 44614; Mohan et al., GCN 44619; Sánchez et al., GCN 44632), which was triggered by Einstein Probe (EP260514a, Cheng et al., GCN 44613). The observation started at 2026-05-15T03:03:58 UTC, 10.13 hours post trigger in the VT_B (400-650 nm) and VT_R (650-1000 nm) channels simultaneously. An uncatalogued optical source was detected within WXT's error box (Cheng et al., GCN 44613) in both channels, compared to the Legacy Survey. The following measurements are in the AB magnitude without correction for Galactic extinction: Mid time | Band | Exposure Time | Brightness 11.96 h VT_B 44*50 s 23.15 +/- 0.22 mag 11.97 h VT_R 39*50 s 22.03 +/- 0.14 mag 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/44638. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 42765] Fermi GRB 260516B: Global MASTER-Net observations report
by GCN Circulars 16 May '26

16 May '26
TITLE: GCN CIRCULAR NUMBER: 44637 SUBJECT: Fermi GRB 260516B: Global MASTER-Net observations report DATE: 26/05/16 05:31:19 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-OAGH robotic telescope [1] located in Mexico (OAGH National Institute for Astrophysics, Optics and Electronics) started inspect of the Fermi GRB 260516B ( Fermi GBM team, GCN 44636) errorbox 25 sec after notice time and 66 sec after trigger time at 2026-05-16 05:13:43 UT, with upper limit up to 20.0 mag. The observations began at zenith distance = 33 deg. The sun altitude is -31.9 deg. The galactic latitude b = 62 deg., longitude l = 185 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3317801 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 71 | 2026-05-16 05:13:43 | MASTER-OAGH | (10h 51m 27.92s , +35d 52m 25.3s) | C | 10 | 17.7 | 71 | 2026-05-16 05:13:43 | MASTER-OAGH | (10h 42m 00.53s , +36d 28m 21.0s) | C | 10 | 18.1 | 96 | 2026-05-16 05:14:03 | MASTER-OAGH | (10h 51m 34.28s , +35d 52m 45.8s) | C | 20 | 18.5 | 96 | 2026-05-16 05:14:03 | MASTER-OAGH | (10h 42m 07.12s , +36d 28m 41.3s) | C | 20 | 18.7 | 127 | 2026-05-16 05:14:33 | MASTER-OAGH | (10h 47m 53.89s , +37d 48m 21.6s) | C | 20 | 18.5 | 127 | 2026-05-16 05:14:33 | MASTER-OAGH | (10h 38m 11.43s , +38d 24m 12.2s) | C | 20 | 18.9 | 164 | 2026-05-16 05:15:05 | MASTER-OAGH | (10h 50m 08.55s , +31d 29m 37.4s) | C | 30 | 18.4 | 209 | 2026-05-16 05:15:05 | MASTER-OAGH | (10h 50m 08.53s , +31d 29m 37.5s) | C | 120 | 19.5 | Coadd 164 | 2026-05-16 05:15:05 | MASTER-OAGH | (10h 41m 11.47s , +32d 05m 27.5s) | C | 30 | 19.0 | 209 | 2026-05-16 05:15:05 | MASTER-OAGH | (10h 41m 11.47s , +32d 05m 27.7s) | C | 120 | 19.9 | Coadd 209 | 2026-05-16 05:15:45 | MASTER-OAGH | (10h 50m 12.93s , +31d 31m 17.3s) | C | 40 | 18.6 | 209 | 2026-05-16 05:15:45 | MASTER-OAGH | (10h 41m 15.84s , +32d 07m 06.8s) | C | 40 | 19.2 | 264 | 2026-05-16 05:16:36 | MASTER-OAGH | (10h 50m 05.67s , +31d 30m 35.8s) | C | 50 | 19.0 | 264 | 2026-05-16 05:16:36 | MASTER-OAGH | (10h 41m 08.74s , +32d 06m 25.1s) | C | 50 | 19.4 | 329 | 2026-05-16 05:17:36 | MASTER-OAGH | (10h 50m 05.11s , +31d 31m 37.8s) | C | 60 | 19.0 | 329 | 2026-05-16 05:17:36 | MASTER-OAGH | (10h 41m 08.14s , +32d 07m 26.7s) | C | 60 | 19.5 | 637 | 2026-05-16 05:22:14 | MASTER-OAGH | (10h 49m 47.37s , +36d 49m 59.5s) | C | 120 | 19.7 | 637 | 2026-05-16 05:22:14 | MASTER-OAGH | (10h 40m 14.19s , +37d 25m 42.5s) | C | 120 | 20.0 | 768 | 2026-05-16 05:24:24 | MASTER-OAGH | (10h 49m 47.37s , +36d 48m 29.8s) | C | 120 | 19.7 | 768 | 2026-05-16 05:24:24 | MASTER-OAGH | (10h 40m 14.62s , +37d 24m 14.1s) | C | 120 | 19.8 | 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/44637. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 42764] GRB 260516B: Fermi GBM Final Real-time Localization
by GCN Circulars 16 May '26

16 May '26
TITLE: GCN CIRCULAR NUMBER: 44636 SUBJECT: GRB 260516B: Fermi GBM Final Real-time Localization DATE: 26/05/16 05:23:15 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 05:12:36 UT on 16 May 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260516B (trigger 800601161.994496 / 260516217). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 161.5, Dec = 36.8 (J2000 degrees, equivalent to J2000 10h 46m, 36d 47'), with a statistical uncertainty of 4.8 degrees. The angle from the Fermi LAT boresight is 58.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260516217/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260516217/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260516217/… View this GCN Circular online at https://gcn.nasa.gov/circulars/44636. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 42763] Fermi Gamma-ray Burst Monitor trigger 800592653/260516119 is not a GRB
by GCN Circulars 16 May '26

16 May '26
TITLE: GCN CIRCULAR NUMBER: 44635 SUBJECT: Fermi Gamma-ray Burst Monitor trigger 800592653/260516119 is not a GRB DATE: 26/05/16 05:07:27 GMT FROM: atrigg2(a)lsu.edu A. C. Trigg (NPP ORAU, NASA MSFC) reports on behalf of the Fermi Gamma-ray Burst Monitor Team: "The Fermi Gamma-ray Burst Monitor (GBM) trigger 800592653/260516119 at 02:50:48.94 UT on 16 May 2026, tentatively classified as a GRB, is in fact not due to a GRB. This trigger is likely due to an accidental trigger." View this GCN Circular online at https://gcn.nasa.gov/circulars/44635. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 42762] GRB 260515A: SVOM/VT optical observations
by GCN Circulars 16 May '26

16 May '26
TITLE: GCN CIRCULAR NUMBER: 44634 SUBJECT: GRB 260515A: SVOM/VT optical observations DATE: 26/05/16 03:45:58 GMT FROM: Huali Li at at NAOC, SVOM <lhl(a)nao.cas.cn> H. L. Li, Y. L. Qiu, C. Wu, L. P. Xin, Y. N. Ma, Z. H. Yao, J. R. Xu, X. H. Han, J. Wang, Y. Xu, P. P. Zhang, W. J. Xie, Y. J. Xiao, H. B. Cai, L. Lan, J. S. Deng, J. Y. Wei (NAOC), J. Palmerio, A. Saccardi (CEA/Irfu) report on behalf of the SVOM/VT team. SVOM/VT performed observations with automatic slew of GRB260515A triggered by SVOM/ECLAIRs (sb26051504, Brunet et al., GCN 44622). The observation started at 2026-05-15T19:10:54 UTC, i.e., 155 seconds post trigger in the VT_B (400-650 nm) and VT_R (650-1000 nm) channels simultaneously. An additional ToO observation was performed started at 2026-05-15T20:59:23 UTC, 1.85 hours post trigger. The optical counterpart (He et al., GCN 44623; Saccardi et al., GCN 44624; Sosnovskij et al., GCN 44625; He et al., GCN 44626; Wu et al., GCN 44628; Dennefeld et al., GCN 44633) with redshift z=0.764 (Malesani et al., GCN 44629) was detected clearly in both channels. The following measurements are in the AB magnitude and are not corrected for Galactic extinction: Mid time | Band | Exposure Time | Brightness 3.00 m VT_B 50 s 16.06 +/- 0.05 mag 3.00 m VT_R 50 s 15.49 +/- 0.04 mag 3.91 m VT_B 26*70 s 21.27 +/- 0.08 mag 3.92 h VT_R 19*70 s 20.93 +/- 0.07 mag During our observations the decay slope changed from 1.3 to 0.8. 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/44634. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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[vsnet-grb-info 42761] GRB 260515A: OHP/T193 optical observations
by GCN Circulars 16 May '26

16 May '26
TITLE: GCN CIRCULAR NUMBER: 44633 SUBJECT: GRB 260515A: OHP/T193 optical observations DATE: 26/05/16 03:39:29 GMT FROM: Christophe Adami at LAM <christophe.adami(a)lam.fr> M. Dennefeld (IAP), B. Schneider (LAM), C. Adami (LAM/Pytheas/AMU), S. Basa (LAM/OHP/Pytheas/AMU), E. Le Floc'h (CEA/Irfu), A. Saccardi (CEA/Irfu) report on behalf of a larger collaboration: We observed the field of the SVOM/ECLAIRs GRB 260515A (Brunet et al., GCN 44622; He et al., GCN 44623; Saccardi et al., GCN 44624; Sosnovskij et al., GCN 44625; He et al., GCN 44626; Lipunov et al., GCN 44627; Wu et al., GCN 44628; Malesani et al., GCN 44629) using the T193cm telescope at Observatoire de Haute-Provence (France) with the MISTRAL spectro-imager. We obtained two epochs: 2x5 minutes of exposure in the r-band starting at 2026-05-15T21:29:45 UT (2.36 hr after the trigger), and 3x10 minutes of exposure in the r-band starting at 2026-05-16T001045UT (5.04 hr after the trigger). In the stacked images, the optical counterpart is visible with preliminary magnitudes of: r = 20.42 +/- 0.13 mag (1st visit) r = 21.34 +/- 0.12 mag (2nd visit) The photometric calibration was performed using nearby stars from the PanSTARRS catalog and the STDWeb/STDPipe tools (Karpov 2025), is in the AB system, and is not corrected for Galactic extinction. We acknowledge the excellent support from Observatoire de Haute-Provence and in particular Yoann Degot-Longhi. View this GCN Circular online at https://gcn.nasa.gov/circulars/44633. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…
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