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

[vsnet-grb-info 41539] SVOM GRB260117.82: Global MASTER-Net observations report
by GCN Circulars 18 Jan '26

18 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43444 SUBJECT: SVOM GRB260117.82: Global MASTER-Net observations report DATE: 26/01/18 16:56:24 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 GRB260117.82 (trigger No 1768678985,12h 32m 45.48s , +43d 53m 33.7s, R=0.1628) errorbox 70494 sec after notice time and 72263 sec after trigger time at 2026-01-18 15:47:28 UT, with upper limit up to 19.6 mag. The observations began at zenith distance = 58 deg. The sun altitude is -54.8 deg. The galactic latitude b = 73 deg., longitude l = 133 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3105573 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 72294 | 2026-01-18 15:47:28 | MASTER-Tunka | (12h 32m 04.93s , +43d 44m 06.4s) | C | 60 | 19.6 | 72294 | 2026-01-18 15:47:29 | MASTER-Tunka | (12h 32m 43.91s , +43d 35m 22.6s) | C | 60 | 19.5 | 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/43444. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41538] Fermi-LAT Gamma-ray Observations of IceCube-260115A
by GCN Circulars 18 Jan '26

18 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43443 SUBJECT: Fermi-LAT Gamma-ray Observations of IceCube-260115A DATE: 26/01/18 12:14:23 GMT FROM: Simone Garrappa at Weizmann Institute of Science <simone.garrappa(a)weizmann.ac.il> S. Garrappa (Weizmann Institute of Science), L. Pfeiffer (Univ. of Wuerzburg), S. Buson (DESY, Univ. of Wuerzburg) and C. Bartolini (INFN Bari) on behalf of the Fermi-LAT collaboration: We report an analysis of observations of the vicinity of the high-energy IC260115A neutrino event (GCN 43421) with all-sky survey data from the Large Area Telescope (LAT), on board the Fermi Gamma-ray Space Telescope. The IceCube event was detected on 2026-01-15 at 17:32:35.71 UTC (T0) with J2000 position RA = 145.77 (+2.29, -1.77) deg, Decl. = 12.41 (+1.18, -0.91) deg 90% PSF containment (J2000). No cataloged gamma-ray sources are found within the 90% IC260115A localization error (4FGL-DR4; The Fourth Fermi-LAT catalog Data Release 4, The Fermi-LAT collaboration 2023, arXiv:2307.12546). We searched for the existence of intermediate (days to years) timescale emission from a new gamma-ray transient source. Preliminary analysis indicates no significant (>5sigma) new excess emission (> 100 MeV) within the IC260115A 90% confidence localization. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IC260115A best-fit position, the >100 MeV flux upper limit (95% confidence) is <4.3e-10 ph cm^-2 s^-1 for ~17-years (2008-08-04 / T0), <3.8e-09 (<2.9e-07) ph cm^-2 s^-1 for a 1-month (1-day) integration time before T0. Since Fermi normally operates in an all-sky scanning mode, regular monitoring of this source will continue. For this source, the Fermi-LAT contact person is S. Garrappa (simone.garrappa at weizmann.ac.il). The Fermi LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden. View this GCN Circular online at https://gcn.nasa.gov/circulars/43443. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41537] Swift trigger on the HMXB 1A 1118-61
by GCN Circulars 18 Jan '26

18 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43442 SUBJECT: Swift trigger on the HMXB 1A 1118-61 DATE: 26/01/18 11:57:09 GMT FROM: K.L. Page at U Leicester <klp5(a)leicester.ac.uk> R. Gupta (NASA GSFC), N. P. M. Kuin (UCL-MSSL), K. L. Page (U Leicester) and T. Sakamoto (AGU) report on behalf of the Neil Gehrels Swift Observatory Team: At 11:27:54 UT, the Swift Burst Alert Telescope (BAT) triggered and located the HMXB 1A 1118-61 (trigger 1442056). Swift slewed immediately to the source. The BAT on-board calculated location is RA, Dec 170.230, -61.909 which is RA(J2000) = 11h 20m 55s Dec(J2000) = -61d 54' 32" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). As is usual for an image trigger, the light-curve does not show significant structure. The XRT began observing the field at 11:29:57.7 UT, 122.8 seconds after the BAT trigger. XRT found a bright X-ray source located at RA, Dec 170.2386, -61.9161 which is equivalent to: RA(J2000) = 11h 20m 57.26s Dec(J2000) = -61d 54' 58.0" with an uncertainty of 5.1 arcseconds (radius, 90% containment). This location is 29 arcseconds from the BAT onboard position, within the BAT error circle. This position is 1.8 arcseconds from a known X-ray source: 1A 1118-61. This source is in the Swift XRT LSXPS catalogue with a mean 0.3-10 keV count-rate of 0.2537 +/- 0.0012 ct/sec; see https://www.swift.ac.uk/LSXPS/LSXPS%20J112057.1-615459 for details of these previous observations. No event data are yet available to determine the column density using X-ray spectroscopy. UVOT took a finding chart exposure of 250 seconds with the U filter starting 188 seconds after the BAT trigger. The source is clearly detected at a U magnitude of 12.7. No correction has been made for the large, but uncertain, extinction expected. This is the second recent trigger by Swift-BAT on this source, following yesterday's event reported in GCN Circ. 43435, showing that the source is increasing in brightness. View this GCN Circular online at https://gcn.nasa.gov/circulars/43442. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41536] GRB 260117A: SVOM/VT optical candidate
by GCN Circulars 18 Jan '26

18 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43441 SUBJECT: GRB 260117A: SVOM/VT optical candidate DATE: 26/01/18 08:09:33 GMT FROM: Huali Li at at NAOC, SVOM <lhl(a)nao.cas.cn> H. L. Li, C. Wu, Y. N. Ma, Y. L. Qiu, Z. H. Yao, 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. T. Palmerio, D. Adrien(CEA/Irfu) report on behalf of the SVOM/VT team. SVOM/VT performed ToO observation for the long faint burst GRB 260117A triggered by SVOM/ECLAIRs (sb26011705, Palmerio et al., GCN 43437). The observation started at 2026-01-17T22:14:53 UTC, i.e., 2.398 hours post trigger in the VT_B (400nm-650nm) and VT_R (650nm-1000nm) channels simultaneously. An uncatalogued source was detected only in VT_R stacked images within the error box of EP/FXT and source 1 from Swift-XRT (Salvaggio et al., GCN 43439; Evans et al., GCN 43438), compared to the Legacy survey catalog. It is also located in the error box of ECLAIRs (Palmerio et al., GCN 43437). The position is at R.A., Dec. = 188.138564, 43.912747 degrees, equivalent to: R.A. (J2000) = 12:32:33.25 Dec. (J2000) = +43:54:45.89 with an uncertainty of 0.5 arcsec. The measurements in AB magnitudes are given below: Mid_time Band Exposure Time Magnitude (AB) 4.36 hour VT_R 68*70 sec 22.98+/-0.25 4.36 hour VT_B 73*70 sec >23.8 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/43441. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41535] GRB 260117A: SVOM/C-GFT upper limit
by GCN Circulars 18 Jan '26

18 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43440 SUBJECT: GRB 260117A: SVOM/C-GFT upper limit DATE: 26/01/18 05:54:34 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> C. Wu (NAOC), Z. Kang (CHO), L.P. Xin, X.H. Han, P.P. Zhang, X.M. Lu (NAOC), Z.W. Li, Y. Lv (CHO), R.S. Zhang, Y.J. Xiao, Y.L. Qiu, J. Wang, J.S. Deng, L. Huang, J.Y. Wei (NAOC), J. T. Palmerio, D. Adrien(CEA/Irfu) report on behalf of the SVOM/C-GFT team: We observed the field of GRB 260117A (SVOM trigger: sb26011705) detected by SVOM/ECLAIRs (Palmerio et al., GCN 43437) with LATIOS on SVOM/C-GFT. Observations started at 2026-01-17T19:44:47 UTC, ~82 seconds after the trigger. We obtained g, r, and i-band follow-up imaging. After preliminary analysis，no credible candidate was detected within the error box provided by EP/FXT and Swift/XRT (Evans et al., GCN 43438; Salvaggio et al., GCN 43439) in our images. The 3-upper limits in the early phase are: | Mid_t - T0 (min) | Exposure Time (s) | Band | Upper Limit (AB) | |-----------------|-------------------|------|------------------| | 4.6 | 5×10 | i | 18.5 | | 14.1 | 10×30 | g | 19.7 | The photometry was calibrated against UCAC4 catalogue and no correction for Galactic dust extinction was applied. We thank the observation assistants Bo-Wen Li and Hong-Xv 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/43440. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41534] GRB 260117A: Swift-XRT observations
by GCN Circulars 18 Jan '26

18 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43439 SUBJECT: GRB 260117A: Swift-XRT observations DATE: 26/01/18 04:47:03 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> C. Salvaggio (INAF-OAB), M. Ferro (INAF-OAB), R. Brivio (INAF-OAB), D.N. Burrows (PSU), S. Lanava (PSU), S. Dichiara (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester) and P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the SVOM/ECLAIRs-detected burst GRB 260117A, collecting 2.9 ks of Photon Counting (PC) mode data between T0+12.5 ks and T0+19.8 ks. Two uncatalogued X-ray sources have been detected, however none of them is above the RASS limit or shows definitive signs of fading. Therefore, at the present time we cannot identify which, if any, is the afterglow. Details of these sources are given below: Source 1: RA (J2000.0): 188.1380 = 12h 32m 33.12s Dec (J2000.0): +43.9131 = +43d 54' 47.3" Error: 5.3 arcsec (radius, 90% conf.) Count-rate: (8.6 +/- 2.1)e-3 ct s^-1 Distance: 152 arcsec from SVOM/ECLAIRs position. Flux: (3.90 +/- 0.93)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV) Source 2: RA (J2000.0): 188.3043 = 12h 33m 13.03s Dec (J2000.0): +43.8449 = +43d 50' 41.7" Error: 5.8 arcsec (radius, 90% conf.) Count-rate: (4.0 [+1.7, -1.4])e-3 ct s^-1 Distance: 343 arcsec from SVOM/ECLAIRs position. Flux: (1.29 [+0.56, -0.44])e-10 erg cm^-2 s^-1 (observed, 0.3-10 keV) 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/ToO_GRBs/00021898. This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/43439. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41533] GRB 260117A: Swift ToO observations
by GCN Circulars 17 Jan '26

17 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43438 SUBJECT: GRB 260117A: Swift ToO observations DATE: 26/01/17 23:10:27 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> P. A. Evans (U. Leicester) reports on behalf of the Swift team: Swift has initiated a ToO observation of the SVOM/ECLAIRs-detected event GRB 260117A. Automated analysis of the XRT data will be presented online at https://www.swift.ac.uk/ToO_GRBs/00021898 Any uncatalogued X-ray sources detected in this analysis will be reported on this website and via GCN COUNTERPART notices. These are not necessarily related to the SVOM/ECLAIRs event. Any X-ray source considered to be a probable afterglow candidate will be reported via a GCN Circular after manual consideration. Details of the XRT automated analysis methods are detailed in Evans et al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8). This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/43438. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41532] GRB 260117A: SVOM detection of a long faint burst
by GCN Circulars 17 Jan '26

17 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43437 SUBJECT: GRB 260117A: SVOM detection of a long faint burst DATE: 26/01/17 20:12:45 GMT FROM: SVOM_group <svomgroup(a)bao.ac.cn> J. T. Palmerio, D. Adrien, S. Schanne, D. Turpin (CEA/Irfu), F. Piron (LUPM), report on behalf of the SVOM mission team: At 2026-01-17T19:43:25 UTC (T0), SVOM/ECLAIRs triggered and located the gamma-ray burst GRB 260117A (SVOM burst-id sb26011705). 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 Count-Rate Trigger (CRT), which produced a sequence of 1 alert. CRT provided the alert with the best signal-to-noise-ratio in the image (SNR) of 8.05 in the [5-20] keV energy band over a time window of 20.48 seconds starting at 2026-01-17T19:43:05. The localization of the best alert is R.A., Dec. 188.1895, 43.8927 degrees: R.A. (J2000) = 12h32m45.49s Dec. (J2000) = 43d53m33.87s with a 90% confidence level (C.L.) radius of 9.77 arcmin (including systematic error of 2 arcmin added in quadrature). This burst was also detected by SVOM/GRM with a significance of 8.90. The SVOM/GRM light curve shows a double peak structure with a T90 duration of about 20 (-4 +5) seconds. Due to the detection significance being below the slew threshold, no immediate slew was performed on this burst. No X-ray observation could be performed by SVOM/MXT for the time being. No optical observation could be performed by SVOM/VT for the time being. 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 Jesse T. Palmerio: jesse.palmerio(a)cea.fr. Please contact the BA by email if you require additional information. View this GCN Circular online at https://gcn.nasa.gov/circulars/43437. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41531] EP 260116a: COLIBRÍ optical upper limit
by GCN Circulars 17 Jan '26

17 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43436 SUBJECT: EP 260116a: COLIBRÍ optical upper limit DATE: 26/01/17 10:52:27 GMT FROM: Francesco at Aix-Marseille Université, CPPM/CNRS <francesco.magnani.work(a)gmail.com> Francesco Magnani (CPPM), Leonardo García García (UNAM), Stéphane Basa (UAR Pytheas), Jean-Luc Atteia (IRAP), William H. Lee (UNAM), Alan M. Watson (UNAM), Edilberto Aguilar-Ruiz (UNAM), Camila Angulo (UNAM), Dalya Akl (NYUAD), Sarah Antier (IJCLAB), Rosa L. Becerra (UNAM), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Jean-Grégoire Ducoin (CPPM), Francis Fortin (IRAP), Ramandeep Gill (UNAM), Noémie Globus (UNAM), Asuka Kuwata (UNAM), Nikos Mandarakas (LAM), Diego López-Cámara (UNAM), Enrique Moreno Méndez (UNAM), Margarita Pereyra (UNAM), Ny Avo Rakotondrainibe (LAM), Fredd Sánchez Álvarez (UNAM), Benjamin Schneider (LAM) and Antonio de Ugarte Postigo (LAM): We imaged the field of the EP 260116a (C. Wang at al., GCN Circ. 43424) using the DDRAGO two-channel wide-field imager on the COLIBRÍ telescope. We observed from 2026-01-17 06:05:01 to 07:29:06 UTC (from 29.9 to 31.3 hours after the trigger) and obtained 64 minutes of simultaneous exposure in the r, z filters. The data were reduced and coadded with the COLIBRÍ pipeline and analysed with STDWeb/STDPipe (Karpov 2025). The photometry was calibrated using nearby stars from the PanSTARRS DR1 catalog, is in the AB system, and is not corrected for Galactic extinction. In the stacked image, we do not detect any new optical source at the EP/WXT error region (C. Wang et al., GCN Circ. 43424) down to the following 3-sigma limit: r > 23.52 z > 22.44 This upper limit is consistent with the one reported by Junjie-Jin et al. (GCN Circ. 43425), V. Lipunov et al. (GCN Circ. 43427), A. Gupta et al. (GCN Circ. 43430), and A. Bochenek et al. (GCN Circ. 43432). We thank the staff of the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir and the COLIBRÍ and DDRAGO engineering teams. COLIBRÍ is an astronomical observatory developed and operated jointly by France (AMU, CNES and CNRS) and Mexico (UNAM and SECIHTI). It is located at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir, Baja California, Mexico. View this GCN Circular online at https://gcn.nasa.gov/circulars/43436. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 41530] Swift triggered on the HMXB 1A 1118-61
by GCN Circulars 17 Jan '26

17 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43435 SUBJECT: Swift triggered on the HMXB 1A 1118-61 DATE: 26/01/17 06:59:18 GMT FROM: K.L. Page at U Leicester <klp5(a)leicester.ac.uk> R. Gupta (NASA GSFC) and K. L. Page (U Leicester) report on behalf of the Neil Gehrels Swift Observatory Team: At 06:28:58 UT, the Swift Burst Alert Telescope (BAT) triggered and located the HMXB 1A 1118-61 (trigger 1441823). Swift slewed soon after the event. The BAT on-board calculated location is RA, Dec 170.183, -61.905 which is RA(J2000) = 11h 20m 44s Dec(J2000) = -61d 54' 17" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a complex structure. This is an image-triggered event. The XRT began observing the field at 06:35:17.6 UT, 378.7 seconds after the BAT trigger. XRT found a bright X-ray source located at RA, Dec 170.2403, -61.9170 which is equivalent to: RA(J2000) = 11h 20m 57.67s Dec(J2000) = -61d 55' 01.2" with an uncertainty of 5.5 arcseconds (radius, 90% containment). This location is 106 arcseconds from the BAT onboard position, within the BAT error circle. This position is 4.3 arcseconds from a known X-ray source: LSXPS J112057.1-615459. This source is in the Swift XRT LSXPS catalogue with a mean 0.3-10 keV count-rate of 0.2537 +/- 0.0012 ct/sec; see https://www.swift.ac.uk/LSXPS/LSXPS%20J112057.1-615459 for details of these previous observations. No event data are yet available to determine the column density using X-ray spectroscopy. This trigger occurred just as Swift was exiting the SAA, so it is not clear at this time whether the source has actually brightened, or if the trigger was caused by the enhanced particle background. View this GCN Circular online at https://gcn.nasa.gov/circulars/43435. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0