February 2026 - vsnet-grb-info - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-grb-info 41769] GRB 260208B: EP-FXT observation
by GCN Circulars 09 Feb '26

09 Feb '26

TITLE: GCN CIRCULAR NUMBER: 43663 SUBJECT: GRB 260208B: EP-FXT observation DATE: 26/02/09 11:06:20 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> S. Q. Jiang, H. N. Yang, Y. L. Wang, Y. Liu (NAO, CAS), Z. H. Yang, Q. C. Zhao (IHEP, CAS) on behalf of the Einstein Probe (EP) team: EP-FXT performed a follow-up observation on GRB 260208B detected by Fermi/GBM (The Fermi GBM team, GCN 43638; Preis & Greiner, GCN 43639; Sonawane et al., GCN 43649), Fermi/LAT (Longo et al., GCN 43647) and SVOM/GRM (Luo et al., GCN 43650) at 2026-02-09T06:37:35 (UTC), about 20.748 hours after the Fermi/GBM trigger. Two uncatalogued X-ray sources are detected around the Fermi/LAT error circle. Preliminary informations are listed as follows: Source 1: EPF_J063834.1-135348 RA (J2000): 99.6419 Dec (J2000): -13.8965 Flux: 1.12 x 10^-13 erg/cm^2/s (observed, 0.5-10 keV) Source 2: EPF_J063827.9-134635 RA (J2000): 99.6162 Dec (J2000): -13.7764 Flux: 0.96 x 10^-13 erg/cm^2/s (observed, 0.5-10 keV) The position is consistent with the source 1 detected by Swift-XRT (Evans et al., GCN 43651) and the optical candidate detected by SVOM/VT (Li et al., GCN 43659). The position uncertainties of the above sources are about 20 arcsec in radius (90% C.L. statistical and systematic). The current result is based on the FXT on-board alert and will be updated when the telemetry data are 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/43663. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41768] GRB 260208A: NOT spectroscopic redshift z = 2.36
by GCN Circulars 09 Feb '26

09 Feb '26

TITLE: GCN CIRCULAR NUMBER: 43662 SUBJECT: GRB 260208A: NOT spectroscopic redshift z = 2.36 DATE: 26/02/09 10:13:18 GMT FROM: Antonio de Ugarte Postigo at LAM, CNRS <adeugartepostigo(a)gmail.com> Dimple (U. Birmingham), D. B. Malesani (DAWN/NBI and Radboud), A. de Ugarte Postigo (LAM), A. Saccardi (CEA/Irfu), G. Corcoran (UCD), B. P. Gompertz (U. Birmingham), L. Izzo (INAF/OAC and DARK/NBI), A. Martin-Carrillo (UCD) and S. Bijavara Seshashayana (NOT and Malmo Univ.) report on behalf of a larger collaboration: We observed the optical counterpart AT2026ciw (Podesta et al., GCN 43640; Wortley et al., GCN 43641; Ma et al., GCN 43655; Ahumada et al., GCN 43657, Dimple et al., GCN 43661) of the GRB 260208A detected by Fermi (Fermi GBM Team, GCN 43635; Sonawane et al., GCN 43642; Longo et al., GCN 43645) and GECAM-B (Luo et al., GCN 43658), which was also detected in X-rays (Dichiara et al., GCN 43652). Observations started at 05:45:58 UT on 9 February 2026 (24.64 hr after the burst) and consisted of 4x1200 s exposures with grism 4, covering the wavelength range between 3200 and 9600 Å. From a preliminary reduction of the spectrum, a trough due to Lya absorption is visible at 4080 AA. From the detection of multiple absorption features, which we interpret as due to O I, C II, Si IV, Si II, C IV, Fe II, Al II, and Al III, we infer a redshift of z = 2.36. View this GCN Circular online at https://gcn.nasa.gov/circulars/43662. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41767] GRB 260208A: Liverpool Telescope optical detection
by GCN Circulars 09 Feb '26

09 Feb '26

TITLE: GCN CIRCULAR NUMBER: 43661 SUBJECT: GRB 260208A: Liverpool Telescope optical detection DATE: 26/02/09 10:00:09 GMT FROM: Dimple at University of Birmingham <dimplepanchal96(a)gmail.com> Dimple (U. Birmingham), B. P. Gompertz (U. Birmingham), D. O'Neill (U. Birmingham), and D. B. Malesani (DAWN/NBI and Radboud) report on behalf of a larger collaboration: We conducted follow-up observations of GRB 260208A (Fermi GBM team, GCN 43635; Sonawane et al., GCN 43642; Longo et al., GCN 43645; Luo et al., GCN 43658) with the IO:O camera on the 2m robotic Liverpool Telescope (LT). Observations began at 03:49:38 UT on 2026-02-09, ~22.8 hr after the Fermi trigger, and consisted of 5 x 180 s exposures in each of the SDSS r and i filters. We detect the optical counterpart (Podesta et al., GCN 43640; Wortley et al., GCN 43641; Ma et al., GCN 43655; Ahumada et al., GCN 43657; also detected in X-rays, Dichiara et al., GCN 43652) in both filters, and measure an AB magnitude of r = 20.63 ± 0.04. Magnitudes are calibrated against nearby Pan-STARRS stars and are not corrected for Galactic extinction. View this GCN Circular online at https://gcn.nasa.gov/circulars/43661. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41766] Fermi GRB 260208C: Global MASTER-Net observations report
by GCN Circulars 09 Feb '26

09 Feb '26

TITLE: GCN CIRCULAR NUMBER: 43660 SUBJECT: Fermi GRB 260208C: Global MASTER-Net observations report DATE: 26/02/09 09:30:23 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-OAFA robotic telescope [1] located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 260208C ( Fermi GBM team, GCN 43646) errorbox 63027 sec after notice time and 63048 sec after trigger time at 2026-02-09 08:43:07 UT, with upper limit up to 19.1 mag. The observations began at zenith distance = 61 deg. The sun altitude is -17.5 deg. The galactic latitude b = -20 deg., longitude l = 347 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3126450 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 63078 | 2026-02-09 08:43:07 | MASTER-OAFA | (18h 44m 17.79s , -49d 24m 20.8s) | C | 60 | 18.5 | 63138 | 2026-02-09 08:43:07 | MASTER-OAFA | (18h 44m 17.79s , -49d 24m 20.8s) | C | 180 | 19.0 | Coadd 63154 | 2026-02-09 08:44:22 | MASTER-OAFA | (18h 44m 23.14s , -49d 24m 13.2s) | C | 60 | 18.5 | 63231 | 2026-02-09 08:45:39 | MASTER-OAFA | (18h 44m 20.60s , -49d 22m 30.2s) | C | 60 | 18.5 | 63307 | 2026-02-09 08:46:55 | MASTER-OAFA | (18h 44m 25.93s , -47d 23m 58.0s) | C | 60 | 18.5 | 63367 | 2026-02-09 08:46:55 | MASTER-OAFA | (18h 44m 25.93s , -47d 23m 58.0s) | C | 180 | 18.9 | Coadd 63385 | 2026-02-09 08:48:13 | MASTER-OAFA | (18h 44m 28.06s , -47d 22m 15.4s) | C | 60 | 18.4 | 63458 | 2026-02-09 08:49:26 | MASTER-OAFA | (18h 44m 23.21s , -47d 22m 58.9s) | C | 60 | 18.4 | 63534 | 2026-02-09 08:50:42 | MASTER-OAFA | (18h 44m 11.06s , -51d 22m 15.4s) | C | 60 | 18.6 | 63594 | 2026-02-09 08:50:42 | MASTER-OAFA | (18h 44m 11.06s , -51d 22m 15.4s) | C | 180 | 19.1 | Coadd 63610 | 2026-02-09 08:51:59 | MASTER-OAFA | (18h 44m 17.39s , -51d 23m 13.9s) | C | 60 | 18.6 | 63684 | 2026-02-09 08:53:12 | MASTER-OAFA | (18h 44m 10.04s , -51d 24m 11.4s) | C | 60 | 18.6 | 64223 | 2026-02-09 09:02:11 | MASTER-OAFA | (18h 59m 29.75s , -47d 23m 37.4s) | C | 60 | 18.2 | 64299 | 2026-02-09 09:03:27 | MASTER-OAFA | (18h 59m 22.68s , -47d 24m 34.6s) | C | 60 | 18.1 | 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/43660. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41765] GRB 260208B: SVOM/VT optical candidate
by GCN Circulars 09 Feb '26

09 Feb '26

TITLE: GCN CIRCULAR NUMBER: 43659 SUBJECT: GRB 260208B: SVOM/VT optical candidate DATE: 26/02/09 09:10:45 GMT FROM: Huali Li at at NAOC, SVOM <lhl(a)nao.cas.cn> H. L. Li, C. W. Wang, Y. L. Qiu, Y. N. Ma, Z. H. Yao, C. Wu, L.P. Xin, X. H. Han, J. Wang, Y. Xu, P. P. Zhang, W. J. Xie, Y. J. Xiao, H. B. Cai, L. Lan, J. R. Xu, J. S. Deng, J. Y. Wei (NAOC), J. Palmerio (CEA/Irfu) report on behalf of the SVOM/VT team. SVOM/VT performed ToO observation to GRB 260208B detected by Fermi-GBM (The Fermi GBM team, GCN 43638; Preis & Greiner, GCN 43639; Sonawane et al., GCN 43649), Fermi-LAT (Longo et al., GCN 43647) and SVOM/GRM (Luo et al., GCN 43650). The observation started at 2026-02-08T18:13:53 UTC, i.e., 8.359 hours post trigger in the VT_B (400nm-650nm) and VT_R (650nm-1000nm) channels simultaneously. An uncatalogued source was detected within the error box of source 1 detected by Swift-XRT (Evans et al., GCN 43651). The position is at R.A., Dec. = 99.619042, -13.774177 degrees, equivalent to: R.A. (J2000) = +06:38:28.57 Dec. (J2000) = -13:46:27.04 with an uncertainty of 0.5 arcsec. The measurements in AB magnitudes are given below: Mid_time Band Exposure Time Magnitude (AB) 10.341 hour VT_R 53*50 sec 22.3+/-0.2 mag 10.341 hour VT_B 57*50 sec > 23.5 mag Our photometry was not corrected for Galactic extinction. Further SVOM/VT ToO observations are scheduled. 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/43659. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41764] GRB 260208A: GECAM-B observation of a bright burst
by GCN Circulars 09 Feb '26

09 Feb '26

TITLE: GCN CIRCULAR NUMBER: 43658 SUBJECT: GRB 260208A: GECAM-B observation of a bright burst DATE: 26/02/09 05:50:39 GMT FROM: Xinghao Luo at IHEP <2952704891(a)qq.com> Xing-Hao Luo, Zheng-Hang Yu, Chen-Wei Wang, Shao-Lin Xiong (IHEP) report on behalf of GECAM team: GECAM-B was triggered in-flight by GRB 260208A, at 2026-02-08T05:07:30.550 UTC (denoted as T0), which is also detected by Fermi/GBM (Fermi GBM team, GCN #43635) and Fermi/LAT (Fermi LAT team, GCN #43645). According to the GECAM-B light curves in about 70-6000 keV, this burst mainly consists of multiple pulses with a duration (T90) of 38 +2/-1 s. The GECAM-B light curve can be found here: https://www.bursthub.cn//admin/static/gecambgrb260208A.png GECAM-B localized this burst to the following position (J2000): Ra: 128.62 deg Dec: 6.25 deg Err: 0.34 deg (1-sigma, statistical only) The time-averaged spectrum from T0-11.5 s to T0+147.5 s is best fitted by a power law function with an exponential high-energy cutoff. The power law index is -1.29 +0.10/-0.08 and the cutoff energy, parameterized as Epeak, is 651 +175/-134 keV. The event fluence (10-1000 keV) in this time interval is (1.62 +0..050/-0.066)E-04 erg/cm^2. Thus GRB 260208A is consistent with Type I GRBs in the 'Amati' relation diagram, as shown at: https://www.bursthub.cn//admin/static/grb250208A_amati.png Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) mission originally consists of two micro-satellites (GECAM-A and GECAM-B) launched in Dec. 2020. As the third member of GECAM constellation, GECAM-C was launched onboard SATech-01 experimental satellite in July 2022. GECAM mission is funded by the Chinese Academy of Sciences (CAS). View this GCN Circular online at https://gcn.nasa.gov/circulars/43658. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41763] GRB 260208A: Zwicky Transient Facility Follow-Up of a Fermi GRB (Trigger 792220053)
by GCN Circulars 09 Feb '26

09 Feb '26

TITLE: GCN CIRCULAR NUMBER: 43657 SUBJECT: GRB 260208A: Zwicky Transient Facility Follow-Up of a Fermi GRB (Trigger 792220053) DATE: 26/02/09 03:44:52 GMT FROM: Tomas Ahumada <tomas.ahumada(a)noirlab.edu> Tomas Ahumada (NOIRLab), Robert Stein (UMD), Theophile du Laz (CIT), Igor Andreoni (UNC), Michael Coughlin (UMN), Mansi Kasliwal (CIT), Shreya Anand (Stanford), report on behalf of the ZTF collaboration: We observed the localization region of the long GRB 260208A (trigger 792220053.24286 / 260208214, Fermi GBM team, GCN 43635) detected by the Gamma-Ray Burst Monitor (GBM) on the Fermi satellite with the Palomar 48 inch telescope equipped with the 47 square degree Zwicky Transient Facility (ZTF) camera. We obtained a series of g- and r-band images covering 130 square degrees beginning at 2026-02-08T10:43:17 (5.6 hours after the burst trigger time). This corresponds to 93% of the probability enclosed in the Earth-occultation corrected GRB localization map. Each exposure was 300 seconds, reaching g-band and r-band median depths of 21.2 mag and 21.2 mag respectively. The images were processed in real-time through the ZTF reduction and image subtraction pipelines at IPAC (Masci et al. 2019). We queried the ZTF alert stream using Kowalski (Duev et al. 2019) through Fritz (Coughlin et al. 2023). We required at least 2 detections separated by at least 15 minutes to select against moving objects. Furthermore, we cross-match our candidates with the Minor Planet Center to flag known asteroids, reject stellar sources (Tachibana and Miller 2018), and apply machine learning algorithms (Mahabal et al. 2019). We require that no spatially coincident ZTF alerts were issued before the detection time of the GBM trigger. We detect the afterglow candidate AT 2026ciw (Podesta et al. GCN 43640, Wortley et al. GCN 43641) as ZTF26aafswob. This is the only source that passed our filtering scheme (Ahumada et al. 2022). The most recent ZTF visit to the field was 3 days prior to the detection. The ZTF detections are reported in the following table: Time (MJD) | Filter | Magnitude 61079.44815970 | g | 19.05 ± 0.05 61079.52940970 | r | 19.11 ± 0.05 This Circular is based on observations obtained with the Samuel Oschin Telescope 48-inch and the 60-inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under Award #2407588 and a partnership including Caltech, USA; Caltech/IPAC, USA; University of Maryland, USA; University of California, Berkeley, USA; University of Wisconsin at Milwaukee, USA; Cornell University, USA; Drexel University, USA; University of North Carolina at Chapel Hill, USA; Institute of Science and Technology, Austria; National Central University, Taiwan; and OKC, University of Stockholm, Sweden. Operations are conducted by Caltech's Optical Observatory (COO), Caltech/IPAC, and the University of Washington at Seattle, USA. View this GCN Circular online at https://gcn.nasa.gov/circulars/43657. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41762] GRB 260209A: Fermi GBM Final Real-time Localization
by GCN Circulars 09 Feb '26

09 Feb '26

TITLE: GCN CIRCULAR NUMBER: 43656 SUBJECT: GRB 260209A: Fermi GBM Final Real-time Localization DATE: 26/02/09 02:56:37 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 02:45:57 UT on 9 Feb 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260209A (trigger 792297962.23625 / 260209115). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 75.8, Dec = 33.0 (J2000 degrees, equivalent to J2000 05h 03m, 33d 00'), with a statistical uncertainty of 9.2 degrees. The angle from the Fermi LAT boresight is 87.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260209115/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260209115/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260209115/… View this GCN Circular online at https://gcn.nasa.gov/circulars/43656. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41761] GRB 260208A: SVOM/VT optical observation
by GCN Circulars 09 Feb '26

09 Feb '26

TITLE: GCN CIRCULAR NUMBER: 43655 SUBJECT: GRB 260208A: SVOM/VT optical observation DATE: 26/02/09 02:31:49 GMT FROM: Yinuo Ma <mayn(a)bao.ac.cn> Y. N. Ma, L. P. Xin, Y. L. Qiu, C. Wu, H. L. Li, Z. H. Yao, 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) report on behalf of the SVOM/VT team. SVOM/VT performed a Target of Opportunity observation of GRB 260208A detected by Fermi/GBM and Fermi/LAT (Fermi GBM Team, GCN 43635; Sonawane et al., GCN 43642; Longo et al., GCN 43645). SVOM/VT began observing the field at 2026-02-08T13:57:59 UTC, 8.842 hours after the trigger, in the VT_B (400nm-650nm) and VT_R (650nm-1000nm) channels simultaneously. With X-band data available, the optical counterpart (Lipunov et al., GCN 43637; Podesta et al., GCN 43640; Wortley et al., GCN 43641) within Swift/XRT Source 1 errorbox (Dichiara et al., GCN 43652) was clearly detected in both VT_B and VT_R bands. The magnitudes are: mid time (h) | exposure time (s) | band | mag (AB) | mag err -------------|-------------------|------|----------|-------- 10.306 | 23*70 | VT_B | 21.15 | 0.06 10.170 | 19*70 | VT_R | 20.40 | 0.04 Our photometry was not corrected for Galactic extinction. Further SVOM/VT ToO observations are scheduled. 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/43655. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41760] Fermi GRB 260208D: Global MASTER-Net observations report
by GCN Circulars 09 Feb '26

09 Feb '26

TITLE: GCN CIRCULAR NUMBER: 43654 SUBJECT: Fermi GRB 260208D: Global MASTER-Net observations report DATE: 26/02/09 00:30:26 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-OAFA robotic telescope [1] located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 260208D ( Fermi GBM team, GCN 43653) errorbox 9638 sec after notice time and 9659 sec after trigger time at 2026-02-09 00:23:45 UT, with upper limit up to 13.1 mag. Observations started at twilight. The observations began at zenith distance = 83 deg. The sun altitude is -11.6 deg. The galactic latitude b = -51 deg., longitude l = 4 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3126729 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 9675 | 2026-02-09 00:23:45 | MASTER-OAFA | (21h 51m 37.44s , -38d 54m 31.8s) | C | 30 | 12.8 | 9722 | 2026-02-09 00:24:32 | MASTER-OAFA | (21h 51m 33.51s , -38d 53m 25.2s) | C | 30 | 13.1 | 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/43654. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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