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[vsnet-grb-info 40875] GRB 251122A / EP251122a: WFST optical observations
by GCN Circulars 22 Nov '25

22 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42807 SUBJECT: GRB 251122A / EP251122a: WFST optical observations DATE: 25/11/22 17:50:46 GMT FROM: ylhua(a)pmo.ac.cn Tian-Rui Sun, Yan-Long Hua (PMO), Chao Wu (NAOC), Jin-Jun Geng, Xue-Feng Wu, Jun-Jie Wei,, Yi-Fang Liang, Ding-Fang Hu, Guan-Xiao Li, Yuan-Tai Yang, Xu Kong, Ji-An Jiang report on behalf of the WFST team: Following the detection of GRB 251122A / EP251122a by SVOM/ECLAIRs (Lin et al., GCN 42800) and by the Einstein Probe (Wang et al., GCN 42799), we conducted follow-up observations with the Wide Field Survey Telescope (WFST Collaboration; arXiv:2306.07590) at the Lenghu Astronomical Observation Base in Qinghai Province, China. WFST began i-band imaging at 2025-11-22T15:45:51 UTC, approximately 1.85 hours after the trigger. The afterglow is clearly detected in the i band, with a preliminary magnitude derived from 10 × 150 s exposures: i = 21.89 ± 0.12 (AB) The photometric calibration was performed using nearby stars from the ATLAS-REFCAT2 catalog, in the AB magnitude system. The reported magnitude is not corrected for Galactic extinction. We thank the staff of WFST and the Lenghu observation station for supporting these observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/42807. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40874] GRB 251122A/EP251122a: SVOM/VT optical observations with VHF data
by GCN Circulars 22 Nov '25

22 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42806 SUBJECT: GRB 251122A/EP251122a: SVOM/VT optical observations with VHF data DATE: 25/11/22 17:25:57 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> H.L. Li, C. Wu (NAOC), J. T. Palmerio (CEA), L.P. Xin, Y. L. Qiu (NAOC), Z.-Y. Lin, C. Lachaud (APC) report on behalf of the SVOM team. SVOM/VT performed an automatic slew on the burst of GRB 251122A/EP251122a (sb25112204) triggered by SVOM/ECLAIRs (Lin et al., GCN 42800) and EP/WXT(Wang et al., GCN 42799). SVOM/VT began observing the field automatically at 2025-11-22T14:02:17 UTC, ~5.15 minutes after the T0 (SVOM trigger time:2025-11-22T13:57:08), 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 Cheng et al. (GCN 42803) in the VT_R band of sequence 1 and 3 with the downlinked VHF data. The AB magnitude was derived as follows: -------------------------------------------- (T-T0)mid exptime band mag 7.65 min 300 sec VT_R 21.82 +/-0.12 88.30 min 300 sec VT_R 21.96 +/-0.15 No correction for Galactic extinction was applied to the photometry. This result is consistent with the report by Wu et al.(GCN 42801), Lipunov et al.(GCN 42802), Saccardi et al.(GCN 42804), Cotter et al.(GCN 42805). 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/42806. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40873] GRB 251122A/EP251122a: Additional, deeper LCO optical r band upper limit
by GCN Circulars 22 Nov '25

22 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42805 SUBJECT: GRB 251122A/EP251122a: Additional, deeper LCO optical r band upper limit DATE: 25/11/22 17:04:27 GMT FROM: Laura Cotter at University College Dublin <laura.cotter(a)ucdconnect.ie> L. Cotter, G. Corcoran (UCD), J. A. Chacon (PUC), D. B. Malesani (DAWN/NBI and Radboud), A. Martin-Carrillo (UCD), P. G. Jonker (Radboud), report on behalf of a larger collaboration: We observed the field of the transient event GRB 251122A / EP251122a detected by EP/WXT (Wang et al., GCN 42799) and by SVOM/ECLAIR (Lin et al., GCN 42800) with the Las Cumbres Observatory (LCO) network. We acquired six 300 s exposures in the r band starting on 2025-11-22 at 15:20:01 UTC (86 min after the EP/EXTtrigger). No new source is detected within the error circle provided by EP/FXT (Wang et al., GCN 42799) and SVOM/MXT (Lin et al., GCN 42800). From the stacked r-band images we obtained a three sigma upper limit of r > 22.4 mag (AB), calibrated against the Pan-STARRS catalog and is not corrected for Galactic extinction. We do not detect the candidate counterpart reported by Cheng et al. (GCN 42803), which was however fainter than our limit and observed at an earlier epoch. Our non-detection is also consistent with previous reports (Wu et al., GCN 42801; Lipunov et al., GCN 42802; Saccardi et al., GCN 42804). View this GCN Circular online at https://gcn.nasa.gov/circulars/42805. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40872] GRB 251122A / EP251122a: LCO optical upper limits
by GCN Circulars 22 Nov '25

22 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42804 SUBJECT: GRB 251122A / EP251122a: LCO optical upper limits DATE: 25/11/22 16:36:43 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> A. Saccardi (CEA/Irfu), D. B. Malesani (DAWN/NBI and Radboud), L. P. Xin (NAOC), D. Turpin, J. T. Palmerio (CEA/Irfu), C. Wu (NAOC), B. Cordier (CEA/Irfu), Z.-Y. Lin, C. Lachaud (APC), report on behalf of the SVOM mission team: We observed the field of GRB 251122A / EP251122a detected by SVOM/ECLAIRs (Lin et al. GCN 42800) and EP/WXT (Wang et al., GCN 42799) with the LCO 1m telescope at the Siding Spring Observatory equipped with the Sinistro instrument. Our observation started at 2025-11-22T14:56:27 (UTC) about 1 hour after the trigger. We obtained 3x200 s exposures in each of the SDSS r and Pan-STARRS z filters. The r-band images are unfortunately trailed, which reduces our sensitivity. In the stacked images, we do not detect any new optical source within the EP/FXT and SVOM/MXT error circles. We measure the following 3-sigma upper limits calibrated against the Pan-STARRS catalog, and not corrected for Galactic extinction: r > 20.8 AB (mid time 80 min after the SVOM T0); z > 20.4 AB (mid time 63 min after the SVOM T0). Our results are consistent with the limits reported by Wu et al. (GCN 42801). We do not detect the candidate counterpart reported by Cheng et al. (GCN 42803), which is fainter and reported at an earlier epoch than our observations. This project is funded by the SVOM collaboration. View this GCN Circular online at https://gcn.nasa.gov/circulars/42804. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40871] EP251122a / GRB 251122A: optical counterpart candidate with Kinder observations
by GCN Circulars 22 Nov '25

22 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42803 SUBJECT: EP251122a / GRB 251122A: optical counterpart candidate with Kinder observations DATE: 25/11/22 16:25:24 GMT FROM: Amar Aryan at National Central University, Institute of Astronomy (NCUIA) <amararyan941(a)gmail.com> Y.-C. Cheng (NCU), J.Y.B Choo (UKM), A.N. Garcia (PUP), A.L.A.M. Nasir (UniSZA), J.-L. Yang (NCU) on behalf of the 47th International School for Young Astronomers (ISYA) in Taipei, A. Aryan, T.-W. Chen, Y.-H. Lee, C.-S. Lin (all NCU), S. Yang (HNAS), A. K. H. Kong (NTHU), J. Gillanders, S. J. Smartt (both Oxford), Y. J. Yang (NYUAD), A. Sankar.K, Y.-C. Pan, C.-C. Ngeow, M.-H. Lee, C.-H. Lai, W.-J. Hou, H.-C. Lin, H.-Y. Hsiao, J.-K. Guo (all NCU), Z. N. Wang, L. L. Fan, G. H. Sun (all HNAS), H.-W. Lin (UMich), H. F. Stevance, S. Srivastav, L. Rhodes (all Oxford), M. Nicholl, M. Fulton, T. Moore, K. W. Smith, C. Angus, A. Aamer (all QUB), A. Schultz and M. Huber (both IfA, Hawaii) report: We observed the field of the fast X-ray transient EP251122a (Wang et al., GCN 42799) using the 1m LOT at Lulin Observatory in Taiwan as part of the Kinder collaboration (Chen & Yang et al., 2025, ApJ, 983, 86, doi:10.3847/1538-4357/adb428). A follow-up observation by SVOM found a temporally and spatially coincident long GRB 251122A (Lin et al. GCN 42800). The first LOT epoch of observations began at 14:13 UTC on the 22nd of November 2025 (MJD 61001.592), 0.31 hr after the EP-WXT trigger. We used the Kinder pipeline (Yang et al. A&A 646, A22) to stack the images and perform template subtraction with the DESI Legacy Survey (Dey et al. 2019, AJ 157, 168) DR10 image. In the difference image, we find a faint, uncataloged optical counterpart candidate at RA, DEC = 02:32:05.1284, +14:07:43.826; lying within the 20" EP-FXT localization circle. The counterpart candidate is likely associated with the DESI Legacy Survey (DR10) galaxy at RA, Dec = 38.0213, 14.1289, with r = 24.64 mag and a photometric redshift of 1.113 ± 0.368. We perform PSF photometry on the position of the source with the stacked frames. The details of the observations and measured PSF magnitude (in the AB system) of the proposed counterpart of EP251122a are as follows: Telescope | Filter | MJD (start) | t-t0 (hr) | Exposure (s) | Magnitude | avg. Seeing | med. Airmass LOT | r | 61001.592 | 0.31 | 300 * 6 | 23.1 +/- 0.2 | 0".93 | 1.01 We caution that the optical counterpart candidate is detected at a level close to the detection limit (>23.2 mag). Our observation is consistent with Wu et al. (GCN 42801) and deeper than their limits. The presented magnitude is calibrated using the field stars from the Pan-STARRS1 DR2 and is not corrected for the expected Galactic foreground extinction of A_r = 0.35 mag in the direction of the transient (Schlafly & Finkbeiner 2011). The methodology, details on the Lulin observatory telescopes, and a compilation of our optical follow-up campaign for FXTs discovered within the first year of operation of the Einstein-Probe mission can be found in Aryan et al. 2025, ApJS, 281, 20, doi:10.3847/1538-4365/adfc69. View this GCN Circular online at https://gcn.nasa.gov/circulars/42803. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40870] EP251122a: Global MASTER-Net observations report
by GCN Circulars 22 Nov '25

22 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42802 SUBJECT: EP251122a: Global MASTER-Net observations report DATE: 25/11/22 16:09:30 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) was pointed to the EP251122a ( EP Team et al., GCN 42799) errorbox 3880 sec after notice time and 5537 sec after trigger time at 2025-11-22 15:26:08 UT, with upper limit up to 19.3 mag. The observations began at zenith distance = 60 deg. The sun altitude is -18.9 deg. The galactic latitude b = -42 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=3049413 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 5627 | 2025-11-22 15:26:08 | MASTER-Kislovodsk | (02h 30m 23.79s , +14d 20m 55.2s) | C | 180 | 16.9 | 5628 | 2025-11-22 15:26:08 | MASTER-Kislovodsk | (02h 30m 33.71s , +13d 58m 00.6s) | C | 180 | 17.8 | 7537 | 2025-11-22 15:57:58 | MASTER-Kislovodsk | (02h 30m 49.90s , +14d 17m 52.7s) | C | 180 | 18.7 | 7539 | 2025-11-22 15:58:00 | MASTER-Kislovodsk | (02h 31m 02.20s , +13d 55m 05.3s) | C | 180 | 19.3 | 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/42802. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40869] GRB 251122A/EP251122a: SVOM/C-GFT upper limit
by GCN Circulars 22 Nov '25

22 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42801 SUBJECT: GRB 251122A/EP251122a: SVOM/C-GFT upper limit DATE: 25/11/22 16:06:03 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> Chao WU (NAOC), Zhe Kang (CHO), Liping Xin(NAOC), Xuhui Han(NAOC), Pinpin Zhang (NAOC), Xiaomeng Lu (NAOC), Zhenwei Li (CHO), You Lv (CHO), Ruosong Zhang (NAOC), Yujie Xiao(NAOC), Yulei Qiu(NAOC), Jing Wang (NAOC), Jinsong Deng(NAOC), Lei Huang(NAOC), Jianyan Wei (NAOC), Z.-Y. Lin, C. Lachaud (APC) report on behalf of the SVOM/C-GFT team: We observed the field of GRB 251122A detected by EP/WXT(Wang et al., GCN 42799, ID:01709248658) and SVOM/ECLAIRs (Lin et al., GCN 42800, SVOM burst-id sb25112204) with LATIOS on SVOM/C-GFT. Observations started at 2025-11-22T13:59:06 UTC, ~118 seconds after the trigger. A series of g, r, and i band images were obtained. No credible candidate was detected within the error box provided by EP/FXT (Wang et al., GCN 42799) and SVOM/MXT (Lin et al., GCN 42800 ) in our images after preliminary processing, the three sigma upper limit is: | Date-Obs (mid-time) | Mid_t - T0 (s) | Exposure Time (s) | Band | Upper Limit (AB) | |---------------------|----------------|-------------------|------|------------------| | 2025-11-22T13:59:45 | 157 | 6×10 | i | 20.05 | The photometry was calibrated against nearby UCAC4 catalogue and no correction for Galactic dust extinction was applied. We thank the observation assistants Bowen Li and Hongyan Xue at Jilin observatory for their excellent support. The Chinese Ground Follow-up Telescope (C-GFT) for the SVOM mission is located at Jilin Station, Changchun Observatory, National Astronomical Observatories, CAS. It features two instruments: (1) CATCH at the Cassegrain focus with a 21 arcsec x 21 arcsec FOV for simultaneous g/r/i-band imaging, and (2) LATIOS, a 4k x 4k CMOS camera at the prime focus with a 1.28 deg x 1.28 deg FOV that images in g, r, and i bands via filter switching. View this GCN Circular online at https://gcn.nasa.gov/circulars/42801. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40868] GRB 251122A / EP251122a: SVOM detection of a long burst
by GCN Circulars 22 Nov '25

22 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42800 SUBJECT: GRB 251122A / EP251122a: SVOM detection of a long burst DATE: 25/11/22 14:26:21 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> Z.-Y. Lin, C. Lachaud (APC), S. Schanne, D. Turpin (CEA/Irfu), T. Maiolino (LUPM), D. Götz (CEA/Irfu), D. B. Malesani (DAWN/NBI and Radboud) report on behalf of the SVOM team: At 2025-11-22T13:57:08 UTC (T0), SVOM/ECLAIRs triggered and located the gamma-ray burst GRB 251122A (SVOM burst-id sb25112204), also triggered by EP/WXT as EP251122a (Wang et al., GCN 42799). The following trigger information was received on the ground with low latency by the SVOM VHF Alert Network. The burst was only detected by the Image Trigger (IMT), which produced a sequence of 6 alerts. IMT provided the alert with the best signal-to-noise-ratio in the image (SNR) of 10.68 in the [5-20] keV energy band over a time window of 327.68 seconds starting at 2025-11-22T13:52:01. The localization of the best alert is R.A., Dec. 38.1450, 14.0645 degrees (J2000) with a 90% confidence level (C.L.) radius of 7.48 arcmin (including systematic error of 2 arcmin added in quadrature). SVOM slewed to the burst. SVOM/MXT began observing the field at 2025-11-22T14:00:05 UTC, 177 seconds after T0. Using onboard processed data we found an uncatalogued X-ray source located at R.A., Dec. 38.026, +14.124 degrees: R.A. (J2000) = 02h32m06s Dec. (J2000) = +14d07m26s with a 90% C.L. radius of 75 arcseconds. This location is 7.8 arcminutes from the ECLAIRs onboard position. This position may be improved as more data is received. VT began observing the field after the slew. The analysis of the data will be published in a future circular. The Space-based multi-band astronomical Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA), French Space Agency (CNES), and the Chinese Academy of Sciences (CAS), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. SVOM/ECLAIRs was developed jointly by CNES, CEA-IRFU, CNRS-IRAP, CNRS-APC. SVOM/GRM was developed by the Institute of High Energy Physics (IHEP) of CAS. SVOM/MXT was developed jointly by CNES, CEA-IRFU, CNRS-IJCLab, University of Leicester, MPE. The Burst Advocate (BA) on shift for this alert is Zheyu Lin: zheyu.lin(a)apc.in2p3.fr. Please contact the BA by email if you require additional information. View this GCN Circular online at https://gcn.nasa.gov/circulars/42800. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40867] EP251122a: Einstein Probe detection of an X-ray transient
by GCN Circulars 22 Nov '25

22 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42799 SUBJECT: EP251122a: Einstein Probe detection of an X-ray transient DATE: 25/11/22 14:20:22 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> B.-T. Wang (YNAO), Y.-H. I. Yin (HKU), G. J. Yang (NAOC), H.-Z. Wu (HUST) and W. D. Zhang (NAOC) on behalf of the Einstein Probe (EP) team: We report on the detection of an X-ray transient by the Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) mission, designated EP251122a. The transient triggered EP-WXT (ID: 01709248658) at 2025-11-22T13:53:51 (UTC). The WXT position of the source is R.A. = 38.017 deg, DEC = 14.132 deg (J2000) with an uncertainty of 3 arcmin in radius (90% C.L. statistical and systematic). A follow-up observation with the Follow-up X-ray Telescope (FXT) was performed automatically. Within the WXT error circle, an uncatalogued X-ray source was detected at R.A. = 38.0199 deg, DEC = 14.1277 deg (J2000) with an uncertainty of 20 arcsec in radius (90% C.L. statistical and systematic). Further information will be updated when the telemetry data is received. 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/42799. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 40866] EP251118a: Continued Optical Detection with Kinder observations
by GCN Circulars 22 Nov '25

22 Nov '25

TITLE: GCN CIRCULAR NUMBER: 42798 SUBJECT: EP251118a: Continued Optical Detection with Kinder observations DATE: 25/11/22 13:04:05 GMT FROM: Amar Aryan at National Central University, Institute of Astronomy (NCUIA) <amararyan941(a)gmail.com> A. Aryan, T.-W. Chen, Y.-H. Lee, C.-S. Lin (all NCU), A. K. H. Kong (NTHU), J. Gillanders, S. J. Smartt (both Oxford), Y. J. Yang (NYUAD), A. Sankar.K, Y.-C. Pan, C.-C. Ngeow, M.-H. Lee, C.-H. Lai, W.-J. Hou, H.-C. Lin, H.-Y. Hsiao, J.-K. Guo (all NCU), S. Yang, Z. N. Wang, L. L. Fan, G. H. Sun (all HNAS), H.-W. Lin (UMich), H. F. Stevance, S. Srivastav, L. Rhodes (all Oxford), M. Nicholl, M. Fulton, T. Moore, K. W. Smith, C. Angus, A. Aamer (all QUB), A. Schultz and M. Huber (both IfA, Hawaii) report: Followed by our previous detection (Lee et al., GCN 42780 ), we continued to observe the field of the fast X-ray transient EP251118a (Jiang et al., GCN 42749) using the 1m LOT at Lulin Observatory in Taiwan as part of the Kinder collaboration (Chen & Yang et al., 2025, ApJ, 983, 86, doi:10.3847/1538-4357/adb428). The first LOT epoch of observations began at 18:09 UTC on November 21, 2025 (MJD 61000.756), 73.45 hours after the EP-WXT trigger. We utilized the astroalign (Beroiz et al. 2020, A&C, 32, 100384) and astropy (Astropy Collaboration et al. 2022, ApJ, 935, 167) packages to align and stack the individual frames. We utilized the Python-based package AutoPhOT (Brennan & Fraser, 2022, A&A, 667, A62) to perform template subtraction with the DESI Legacy Survey (Dey et al. 2019, AJ 157, 168) DR10 image using the 'hotpants' (Becker A., 2015, ascl.soft. ascl:1504.004) algorithm. In the difference image, we onece again clearly detected the optical counterpart candidate proposed by Malesani et al. (GCN 42751) at a spectroscopic redshift of z = 1.216 (An et al., GCN 42756), and confirmed by Belkin et al. (GCN 42758); Yadav et al. (GCN 42760); Busmann et al. (GCN 42763); Francile et al. (GCN 42767); Urquijo-Rodríguez et al. (GCN 42773); Moskvitin et al. (GCN 42785); Gupta et al. (GCN 42787); and Liu et al (GCN 42793) Moreover, we further utilized AutoPhOT to perform the PSF photometry. The details of the observations and the measured magnitude(in the AB system) are as follows: Telescope | Filter | MJD (start) | t-t0 (hr) | Exposure (s) | Magnitude | avg. Seeing | med. Airmass LOT | r | 61000.756 | 73.45 | 300 * 6 | 22.5 +/- 0.1 | 0".92 | 1.12 The presented magnitude is calibrated using the field stars from the ATLAS-RefCat2 catalog from MAST (Tonry J. L. et al. 2018, ApJ, 867, 105) and is not corrected for the expected Galactic foreground extinction of A_r = 0.09 mag in the direction of the transient (Schlafly & Finkbeiner 2011). The methodology, details on the Lulin observatory telescopes, and a compilation of our optical follow-up campaign for FXTs discovered within the first year of operation of the Einstein-Probe mission can be found in Aryan et al. 2025, ApJS, 281, 20, doi:10.3847/1538-4365/adfc69. View this GCN Circular online at https://gcn.nasa.gov/circulars/42798. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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