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

[vsnet-grb-info 41018] GRB 251202A: Swift-XRT afterglow detection
by GCN Circulars 02 Dec '25

02 Dec '25

TITLE: GCN CIRCULAR NUMBER: 42943 SUBJECT: GRB 251202A: Swift-XRT afterglow detection DATE: 25/12/02 11:00:16 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> B. Sbarufatti (INAF-OAB), S. Lanava (PSU), S. Dichiara (PSU), J.A. Kennea (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), C. Salvaggio (INAF-OAB), M. Ferro (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 251202A. We searched for X-ray sources in 759 s of Photon Counting (PC) mode data. The total exposure at the position of the afterglow (see below) is 759 s, obtained between T0+2.4 ks and T0+24.0 ks. An uncatalogued X-ray source are clearly detected within the Einstein Probe/WXT error region. Using 411 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 = 122.11512, +40.61228 which is equivalent to: RA (J2000): 08h 08m 27.63s Dec(J2000): +40d 36' 44.2" with an uncertainty of 2.4 arcsec (radius, 90% confidence). This position is 10.3 arcsec from the EP/FXT position (Zhang et al., GCN Circ. 42937) and 2.2 arcsec from the optical counterpart reported by Li et al. (GCN 42934). The light curve can be modelled with a power-law decay with a decay index of alpha=1.08 (+0.33, -0.24). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.93 (+0.45, -0.22). The best-fitting absorption column is consistent with the Galactic value of 6.5 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.4 x 10^-11 (3.9 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Galactic foreground: 6.5 x 10^20 cm^-2 Intrinsic column: 6 (+/-166) x 10^20 cm^-2 at z=2.785 Photon index: 1.93 (+0.45, -0.22) If the light curve continues to decay with a power-law decay index of 1.08, the count rate at T+24 hours will be 0.018 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 6.3 x 10^-13 (7.2 x 10^-13) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at https://www.swift.ac.uk/xrt_products/03000226. The results of the full analysis of the XRT observations are available at https://www.swift.ac.uk/EP/EP_FIELD00086. This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/42943. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41017] EP251129a/GRB 251129A: NOWT Detection
by GCN Circulars 02 Dec '25

02 Dec '25

TITLE: GCN CIRCULAR NUMBER: 42942 SUBJECT: EP251129a/GRB 251129A: NOWT Detection DATE: 25/12/02 08:20:32 GMT FROM: Abdusamatjan Iskandar at XAO,CAS <abudu(a)xao.ac.cn> Shahidin Yaqup, Abdusamatjan Iskandar, Jinzhong Liu, report on behalf of optical group of the XAO: We imaged the field of the GRB 251129A/EP 251129a (GCN Circ. 42877, 42880, 42884 ) using the Nanshan One-meter Wide-field Telescope (NOWT) at Nanshan Station of Xinjiang Astronomical Observatory (XAO). We observed from 2025-11-29 20:08:26 to 20:32:43 UTC and obtained 6 x 300 s exposure in the V filter. The stack image photometry was calibrated using nearby stars from the GAIA synthesis catalog, without correction for Galactic extinction. We detect a source at the position (RA, DEC(J2000) = 14:57:18.88, +79:17:34.8) reported by GCN Circ.42880, with preliminary magnitude of V = 21.74+-0.64 mag. View this GCN Circular online at https://gcn.nasa.gov/circulars/42942. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41016] GRB 251126A: SVOM/VT optical observation
by GCN Circulars 02 Dec '25

02 Dec '25

TITLE: GCN CIRCULAR NUMBER: 42941 SUBJECT: GRB 251126A: SVOM/VT optical observation DATE: 25/12/02 06:57:14 GMT FROM: zhyao(a)bao.ac.cn Z. H. Yao, Y. L. Qiu, C. Wu, H. L. Li, Y. N. Ma, L. P. Xin, X. H. Han, Y. Xu, J. Wang, P. P. Zhang, W. J. Xie, Y. J. Xiao, H. B. Cai, L. Lan, J. R. Xu, J. S. Deng, J. Y. Wei (NAOC) and J. Palmerio (CEA) report on behalf of the SVOM/VT team. SVOM/VT performed a Target of Opportunity observation of GRB 251126A detected by Swift/BAT (Caputo et al., GCN 42843). SVOM/VT began observing the field at 2025-11-26T19:45:56.502 UTC, 35 minutes after T0, in the VT_B (400nm-650nm) and VT_R (650nm-1000nm) channels simultaneously. With X-band data available, the optical counterpart (Swain et al., GCN 42844; Lipunov et al. GCN 42847; Fu et al., GCN 42848; Reguitti et al., GCN 42849; Broens et al., GCN 42850; Angulo et al., GCN 42855; Pulido-Torres et al., GCN 42856; Gupta et al., GCN 42857; Cotter et al., GCN 42858; Seki et al., GCN 42859; Volnova et al., GCN 42861; Breeveld et al. GCN 42863; Gupta et al., GCN 42864; Burkhonov et al., GCN 42866; Maksut et al., GCN 42868; Moskvitin et al, GCN 42870; Adami et al., GCN 42871; Pankov et al., GCN 42875; Goranskij et al. GCN 42896) was detected in both VT_B and VT_R band within BAT (Caputo et al., GCN 42843; Barthelmy et al. GCN 42876) and XRT's (Caputo et al., GCN 42843; Evans et al., GCN 42845; Goad et al., GCN 42851) error box.We detect a clear fading with a decay slope of approximately 1.6, followed by a rebrightening bump occurring at ~13.48 h after the trigger. The most recent photometric measurement is as follows: mid time (h) | exposure time (s) | band | mag (AB) -------------|-------------------|------|---------------- 25.34 | 20*70 | VT_B | 22.87+/-0.12 25.34 | 20*70 | VT_R | 21.64+/-0.05 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/42941. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41015] EP251130a: SVOM/VT optical observation
by GCN Circulars 02 Dec '25

02 Dec '25

TITLE: GCN CIRCULAR NUMBER: 42940 SUBJECT: EP251130a: SVOM/VT optical observation DATE: 25/12/02 06:52:47 GMT FROM: Yinuo Ma <mayn(a)bao.ac.cn> Y. N. Ma, Y. L. Qiu, C. Wu, H. L. Li, L. P. Xin, 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 performed a Target of Opportunity observation of EP251130a detected by EP/WXT (Wu et al., GCN 42903). SVOM/VT began observing the field at 2025-12-01T16:10:37 UTC, 29.05 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 (Dornic et al., GCN 42904; Lipunov et al., GCN 42906; He et al., GCN 42914; Gupta et al., GCN 42916; Zheng et al., GCN 42917; van Dalen et al., GCN 42918; Moskvitin and Spiridonova, GCN 42919; Aryan et al., GCN 42921; Volnova et al., GCN 42922) was detected within EP/FXT and Swift/XRT errorbox (Zhang et al., GCN 42915; Evans et al., GCN 42908) in both VT_B and VT_R bands. The magnitudes are: mid time (h) | exposure time (s) | band | mag (AB) | mag err -------------|-------------------|------|----------|-------- 29.61 | 23*50 | VT_B | 22.8 | 0.3 29.61 | 23*50 | VT_R | 20.54 | 0.08 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/42940. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41014] EP251202a / GRB 251202A: NOT spectroscopic redshift z = 2.785
by GCN Circulars 02 Dec '25

02 Dec '25

TITLE: GCN CIRCULAR NUMBER: 42939 SUBJECT: EP251202a / GRB 251202A: NOT spectroscopic redshift z = 2.785 DATE: 25/12/02 06:18:17 GMT FROM: Daniele Bjørn Malesani at Cosmic Dawn Center, Niels Bohr Institute <daniele.malesani(a)nbi.ku.dk> Z.P. Zhu (NAOC), D. B. Malesani (DAWN/NBI and Radboud), L. Izzo (INAF/OACN and DARK/NBI), A. de Ugarte Postigo (LAM), D. Xu, X. Liu, S.Q. Jiang, J. An, L.B. He (NAOC), A. Saccardi (CEA/Irfu), R. H. Rasmussen (NOT and Aarhus) report on behalf of a large collaboration: We observed the optical counterpart (Li et al., GCN 42934) of EP251202a (Zhang et al., GCN 42937), which is likely the same event of Fermi GRB 251202A (Fermi GBM team, GCN 42933), using the Nordic Optical Telescope (NOT), equipped with the ALFOSC camera and spectrograph. We obtained 10x120 s and 9x120 s exposures in the r and z bands, respectively, starting on 2025 Dec 2 at 02:51:32 UT. The afterglow is clearly detected in single images, with an AB magnitude of r = 17.27 +/- 0.01 at a mid time of 1.05 hr after the trigger. A sequence of 3 spectra by 1200 s each was then acquired using grism #4, covering the wavelength range 3500-9500 AA. Our first spectrum started on 2025 Dec 2.156 UT (1.93 hr after the EP/WXT trigger). Continuum is detected across the whole wavelength range. A spectral break is detected around 4610 AA, and the onset of the forest is seen blueward of this wavelength. We match existing features to a low-column density Lyman alpha and C IV (unresolved) at z = 2.785, which we believe to be the redshift of the burst. Intervening systems are also seen in Lyman alpha and C IV at z = 2.450 and 2.356. We acknowledge the use of the grbspec.eu tool to analyse this spectrum. View this GCN Circular online at https://gcn.nasa.gov/circulars/42939. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41013] Fermi GRB 251202A: Global MASTER-Net observations report
by GCN Circulars 02 Dec '25

02 Dec '25

TITLE: GCN CIRCULAR NUMBER: 42938 SUBJECT: Fermi GRB 251202A: Global MASTER-Net observations report DATE: 25/12/02 03:30:34 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-SAAO robotic telescope [1] located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 251202A ( Fermi GBM team, GCN 42933) errorbox 570 sec after notice time and 604 sec after trigger time at 2025-12-02 02:00:56 UT, with upper limit up to 18.8 mag. Observations started at twilight. The observations began at zenith distance = 76 deg. The sun altitude is -15.8 deg. The galactic latitude b = 31 deg., longitude l = 177 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3057770 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 634 | 2025-12-02 02:00:56 | MASTER-SAAO | (07h 56m 46.47s , +43d 37m 13.0s) | C | 60 | 17.7 | 694 | 2025-12-02 02:00:56 | MASTER-SAAO | (07h 56m 46.46s , +43d 37m 13.0s) | C | 180 | 18.6 | Coadd 634 | 2025-12-02 02:00:56 | MASTER-SAAO | (07h 59m 07.79s , +43d 21m 09.1s) | C | 60 | 18.0 | 694 | 2025-12-02 02:00:56 | MASTER-SAAO | (07h 59m 07.80s , +43d 21m 09.1s) | C | 180 | 18.8 | Coadd 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/42938. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41012] EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient
by GCN Circulars 02 Dec '25

02 Dec '25

TITLE: GCN CIRCULAR NUMBER: 42937 SUBJECT: EP251202a/GRB 251202A: Einstein Probe detection of an X-ray transient DATE: 25/12/02 03:28:01 GMT FROM: EP Team at NAOC/CAS <ep_ta(a)bao.ac.cn> Y. J. Zhang (THU), R. D. Liang (NAOC) Z. M. Wang (BNU), Y. Wu (NJU), H. N. Yang, H. Sun (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 EP251202a. The transient triggered EP-WXT (ID: 01709249064) at 2025-12-02T01:49:15 (UTC). The WXT position of the source is R.A. = 122.121 deg, DEC = 40.600 deg (J2000) with an uncertainty of 3 arcmin in radius (90% C.L. statistical and systematic). The trigger time and the position of the transient is consistent with that of GRB 251202A detected by Fermi/GBM (GCN 42933). We performed a follow-up observation with the Follow-up X-ray Telescope (FXT), starting at 2025-12-02T02:09:51 (UTC), about 20 minutes after the trigger. Within the WXT error circle, an uncatalogued X-ray source was detected at R.A. = 122.1190 deg, DEC = 40.6125 deg (J2000) with an uncertainty of 20 arcsec in radius (90% C.L. statistical and systematic). The position is 12 arcsec from the optical counterpart reported by Las Cumbres Observatory (Li et al., GCN 42934). 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/42937. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41011] GRB 251201B: Swift-XRT refined Analysis
by GCN Circulars 02 Dec '25

02 Dec '25

TITLE: GCN CIRCULAR NUMBER: 42936 SUBJECT: GRB 251201B: Swift-XRT refined Analysis DATE: 25/12/02 03:23:04 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> V. D'Elia (SSDC & INAF-OAR), B. Sbarufatti (INAF-OAB), D.N. Burrows (PSU), S. Lanava (PSU), S. Dichiara (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), C. Salvaggio (INAF-OAB) and P.A. Evans report on behalf of the Swift-XRT team: We have analysed 6.3 ks of XRT data for GRB 251201B, from 86 s to 23.3 ks after the trigger. The data comprise 362 s in Windowed Timing (WT) mode (the first 6 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The late-time light curve (from T0+6.3 ks) can be modelled with a power-law decay with a decay index of alpha=1.6 (+/-0.3). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.40 (+/-0.04). The best-fitting absorption column is 2.30 (+/-0.12) x 10^21 cm^-2, in excess of the Galactic value of 1.8 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.93 (+0.16, -0.15) and a best-fitting absorption column of 10.0 (+4.5, -4.0) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.5 x 10^-11 (4.3 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 10.0 (+4.5, -4.0) x 10^20 cm^-2 Galactic foreground: 1.8 x 10^20 cm^-2 Excess significance: 3.4 sigma Photon index: 1.93 (+0.16, -0.15) If the light curve continues to decay with a power-law decay index of 1.6, the count rate at T+24 hours will be 3.5 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.2 x 10^-13 (1.5 x 10^-13) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at https://www.swift.ac.uk/xrt_products/01418729. This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/42936. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41010] IceCube-251130A: Upper limits from a search for additional neutrino events in IceCube
by GCN Circulars 02 Dec '25

02 Dec '25

TITLE: GCN CIRCULAR NUMBER: 42935 SUBJECT: IceCube-251130A: Upper limits from a search for additional neutrino events in IceCube DATE: 25/12/02 02:50:34 GMT FROM: Yuhua Yao at IceCube/UW-Madison <yyao255(a)icecube.wisc.edu> The IceCube Collaboration (http://icecube.wisc.edu/) reports: IceCube has performed a search [1] for additional track-like muon neutrino events arriving from the direction of IceCube-251130A (https://gcn.nasa.gov/circulars/42909) in a time range of 1000 seconds centered on the alert event time (2025-11-30 17:45:10.690 UTC to 2025-11-30 18:01:50.690 UTC) during which IceCube was collecting good quality data. Excluding the event that prompted the alert, zero track-like events are found within the 90% containment region of IceCube-251130A. We report a p-value of 1.00 in this time window. IceCube’s sensitivity to neutrino point sources with an E^-2.5 spectrum, expressed as E^2 dN/dE evaluated at 1 TeV, ranges from 4.2e-01 to 5.5e-01 GeV cm^-2 within the 90% spatial containment region of IceCube-251130A in a 1000 second time window. 90% of events IceCube would detect from a source at this declination with an E^-2.5 spectrum have energies in the approximate energy range between 4e+02 GeV and 3e+05 GeV. A subsequent search was performed including 2 days of data centered on the alert event time (2025-11-29 17:53:30.690 UTC to 2025-12-01 17:53:30.690 UTC). In this case, we report a p-value of 1.00, consistent with no significant excess of track events. IceCube’s sensitivity to neutrino point sources with an E^-2.5 spectrum, expressed as E^2 dN/dE evaluated at 1 TeV, ranges from 4.3e-01 to 5.6e-01 GeV cm^-2 within the 90% spatial containment region of IceCube-251130A in a 2 day time window. The IceCube Neutrino Observatory is a cubic-kilometer neutrino detector operating at the geographic South Pole, Antarctica. The IceCube realtime alert point of contact can be reached at roc(a)icecube.wisc.edu. [1] IceCube Collaboration, R. Abbasi et al., ApJ 910 4 (2021) View this GCN Circular online at https://gcn.nasa.gov/circulars/42935. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41009] The EP-WXT trigger 01709249064: Las Cumbres discovery of the optical counterpart
by GCN Circulars 02 Dec '25

02 Dec '25

TITLE: GCN CIRCULAR NUMBER: 42934 SUBJECT: The EP-WXT trigger 01709249064: Las Cumbres discovery of the optical counterpart DATE: 25/12/02 02:44:37 GMT FROM: Wenxiong Li at NAOC <liwenxiong1992(a)gmail.com> Wenxiong Li, Runduo Liang (NAOC), Iair Arcavi (TAU), Ido Keinan (TAU), David Sand (U of Arizona) We observed the position of The EP-WXT trigger 01709249064 with a Las Cumbres 1m telescope at Teide Observatory, Tenerife, 18 mins after the Einstein Probe WXT trigger. We took 2x300s exposures in the broad optical w band. We find a uncataloged source at RA=122.1143 Dec=40.6123 within the EP/WXT error circle and measure the following preliminary photometry calibrated to the r band: MJD 61011.089 Mag 15.6 We find a faint red likely extended source at this position in Legacy Survey data (https://www.legacysurvey.org/viewer). Additional followup is encouraged. View this GCN Circular online at https://gcn.nasa.gov/circulars/42934. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0