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

[vsnet-grb-info 41413] Swift GRB 260104A: Global MASTER-Net observations report
by GCN Circulars 04 Jan '26

04 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43322 SUBJECT: Swift GRB 260104A: Global MASTER-Net observations report DATE: 26/01/04 16:48:28 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 Swift GRB 260104A ( R. Caputo et al., GCN 43315) errorbox 39152 sec after notice time and 39173 sec after trigger time at 2026-01-04 16:29:55 UT, with upper limit up to 15.0 mag. The observations began at zenith distance = 82 deg. The sun altitude is -28.6 deg. The galactic latitude b = -58 deg., longitude l = 36 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3095622 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 39263 | MASTER-Kislovodsk | C | 180 | 13.5 | 39263 | MASTER-Kislovodsk | C | 180 | 14.3 | 39471 | MASTER-Kislovodsk | C | 180 | 13.5 | 39471 | MASTER-Kislovodsk | C | 180 | 14.1 | 39687 | MASTER-Kislovodsk | C | 180 | 14.2 | 39687 | MASTER-Kislovodsk | C | 180 | 15.0 | 39903 | MASTER-Kislovodsk | C | 180 | 14.7 | 39903 | MASTER-Kislovodsk | C | 180 | 15.0 | 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/43322. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41412] GRB 251230A/EP-WXT trigger 01709250693: Mephisto optical upper limits
by GCN Circulars 04 Jan '26

04 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43321 SUBJECT: GRB 251230A/EP-WXT trigger 01709250693: Mephisto optical upper limits DATE: 26/01/04 15:26:20 GMT FROM: Dr. Kaushik Chatterjee at SWIFAR, Yunnan University <mails.kc.physics(a)gmail.com> Kaushik Chatterjee, Guowang Du, Yu Pan, Yifei Ding, Guangya Zeng, Brajesh Kumar, Yuan Fang, Jinghua Zhang, Xingzhu Zou, Xinlei Chen, Xufeng Zhu, Tao Wang, Xinzhong Er, Yuanpei Yang, Xiangkun Liu, Xiaowei Liu (SWIFAR, YNU) report on behalf of the Mephisto Team: The EP-WXT trigger 01709250693 (trigger time 2025-12-30T01:22:21), identified as EP251230a/GRB251230A (Lanava et al., GCN 43252; Li et al. GCN 43255; Wang. C. et al., GCN 43259; Osborne et al., GCN 43263) was observed with the following facility of the Yunnan University, located at the Lijiang Observatory: the 1.6m Multi-channel Photometric Survey Telescope (Mephisto). A set of simultaneous multi-band (ugi and vrz) frames were collected starting from 2025-12-30 UTC19:34:28 (~ 16.9 hr after the trigger) and continued till 2025-12-30 UTC20:00:18. The optical counterpart reported previously (Busmann et al., GCN 43258; Masi et al., GCN 43260; Ghosh et al., GCN 43262; Ma et al., GCN 43265) was not detected in our stacked frames and the upper limits (5 sigma) are listed below. --------------------------------------------------- Start_Time(UT) | Band | Exp(s) | LimMag (AB) --------------------------------------------------- 2025-12-30T19:34:28 | u | 45.0*7 | >21.08 2025-12-30T19:54:43 | v | 45.0*6 | >20.89 2025-12-30T19:34:30 | g | 45.0*6 | >21.36 2025-12-30T19:54:45 | r | 45.0*6 | >21.38 2025-12-30T19:34:30 | i | 45.0*7 | >21.04 2025-12-30T19:54:44 | z | 45.0*6 | >20.32 --------------------------------------------------- Mephisto (Multi-channel Photometric Survey Telescope) is a 1.6-m wide-field multi-channel telescope, the first of its type in the world, capable of imaging the same field of view in three optical bands simultaneously. The facility is operated by the South-Western Institute for Astronomy Research (SWIFAR), Yunnan University. It provides real-time, high-quality colors of stellar objects. The Mephisto mosaic cameras were installed in October 2025. The first light was achieved in all three channels on 10 October 2025 and presently, these are under the commissioning phase. All the data have been reduced by the Mephisto data processing pipeline. Here, we note that the current data processing pipeline is still at a preliminary stage, with flux calibration precision in each band at the level of about 5% or even higher. View this GCN Circular online at https://gcn.nasa.gov/circulars/43321. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41411] GRB 260104A: Swift-XRT refined Analysis
by GCN Circulars 04 Jan '26

04 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43320 SUBJECT: GRB 260104A: Swift-XRT refined Analysis DATE: 26/01/04 14:58:50 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> J.A. Kennea (PSU), D.N. Burrows (PSU), S. Lanava (PSU), A.P. Beardmore (U. Leicester), J.P. Osborne (U. Leicester), E. Ambrosi (INAF-IASFPA) , M. Capalbi (INAF-OAR), M. Perri (SSDC & INAF-OAR) and P.A. Evans report on behalf of the Swift-XRT team: We have analysed 6.3 ks of XRT data for GRB 260104A, from 101 s to 28.3 ks after the trigger. The data comprise 10 s in Windowed Timing (WT) mode (taken while Swift was slewing), with the remainder in Photon Counting (PC) mode. The late-time light curve (from T0+5.1 ks) can be modelled with a power-law decay with a decay index of alpha=1.22 (+0.26, -0.23). A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 1.78 (+0.16, -0.10). The best-fitting absorption column is 3.55 (+3.69, -0.15) x 10^20 cm^-2, consistent with the Galactic value of 3.4 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 3.7 x 10^-11 (4.0 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 3.55 (+3.69, -0.15) x 10^20 cm^-2 Galactic foreground: 3.4 x 10^20 cm^-2 Excess significance: <1.6 sigma Photon index: 1.78 (+0.16, -0.10) If the light curve continues to decay with a power-law decay index of 1.22, the count rate at T+24 hours will be 4.6 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.7 x 10^-13 (1.8 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/01430212. This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/43320. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41410] GRB 260104A: Enhanced Swift-XRT position
by GCN Circulars 04 Jan '26

04 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43319 SUBJECT: GRB 260104A: Enhanced Swift-XRT position DATE: 26/01/04 14:49:33 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team. Using 3264 s of XRT Photon Counting mode data and 6 UVOT images for GRB 260104A, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 337.39920, -21.29552 which is equivalent to: RA (J2000): 22h 29m 35.81s Dec (J2000): -21d 17' 43.9" with an uncertainty of 2.0 arcsec (radius, 90% confidence). This position may be improved as more data are received. The latest position can be viewed at https://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177). This circular was automatically generated, and is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/43319. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41409] GRB 260101A: Swift/UVOT Detection
by GCN Circulars 04 Jan '26

04 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43318 SUBJECT: GRB 260101A: Swift/UVOT Detection DATE: 26/01/04 10:35:48 GMT FROM: noelklin(a)umbc.edu N. Klingler (NASA-GSFC / UMBC / CRESST II) and S. B. Cenko (GSFC) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 260101A 144 s after the BAT trigger (Cenko et al., GCN Circ. 43285). A source consistent with the enhanced XRT position (Evans et al., GCN Circ. 43289) is detected in the initial UVOT exposures. The preliminary UVOT position is: RA (J2000) = 05:45:42.96 = 86.42898 (deg.) Dec (J2000) = +63:35:32.1 = 63.59226 (deg.) with an estimated uncertainty of 0.43 arc sec. (radius, 90% confidence). Detections and 2-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag b 399.7 419.5 19.8 16.57 +/- 0.10 b 548.6 568.4 19.8 16.74 +/- 0.11 b 697.4 717.1 19.7 16.80 +/- 0.11 b 847.1 866.9 19.8 17.20 +/- 0.14 b 1031.0 1200.3 169.3 17.50 +/- 0.11 b 1329.9 1498.6 168.7 17.69 +/- 0.12 b 1628.4 1648.2 19.8 17.81 +/- 0.18 b 21638.8 22547.2 908.4 21.07 +/- 0.27 u 144.3 394.1 249.8 16.09 +/- 0.05 u 523.8 543.5 19.7 16.44 +/- 0.13 u 672.6 692.3 19.7 17.15 +/- 0.18 u 822.4 842.1 19.7 16.97 +/- 0.16 u 875.8 1025.6 149.8 17.12 +/- 0.08 u 1155.7 1324.8 169.1 17.86 +/- 0.18 u 1454.1 1623.5 169.4 17.86 +/- 0.18 u 95366.4 96053.5 687.1 >21.51 v 450.4 470.2 19.8 16.17 +/- 0.14 v 599.0 618.8 19.8 15.87 +/- 0.12 v 747.6 767.4 19.8 16.28 +/- 0.15 v 1081.4 1251.3 169.9 16.98 +/- 0.15 v 1380.2 1549.5 169.3 17.23 +/- 0.17 v 11438.4 12223.4 785.0 19.27 +/- 0.14 v 27138.9 28046.0 907.1 20.55 +/- 0.38 uvw1 499.5 816.9 317.4 >19.48 uvw1 1131.1 1599.0 467.9 >19.74 uvw1 34121.1 34973.5 852.4 >21.44 uvw2 425.8 743.0 317.2 >19.43 uvw2 1057.0 1525.2 468.2 >19.72 uvw2 10532.3 11432.0 899.7 >21.06 uvw2 22553.7 23374.5 820.8 >21.39 uvw2 100888.2 101273.5 385.3 >20.96 uvm2 474.7 643.2 168.5 >18.78 uvm2 1105.7 1424.3 318.6 >18.80 uvm2 28051.2 28842.6 791.4 >21.25 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.197 in the direction of the burst (Schlegel et al. 1998). View this GCN Circular online at https://gcn.nasa.gov/circulars/43318. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41408] GRB 260103A: GECAM-B observation of a burst
by GCN Circulars 04 Jan '26

04 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43317 SUBJECT: GRB 260103A: GECAM-B observation of a burst DATE: 26/01/04 08:59:17 GMT FROM: Xinghao Luo at IHEP <2952704891(a)qq.com> GRB 260103A: GECAM-B observation of a burst Xing-Hao Luo, Chen-Wei Wang, Shao-Lin Xiong, Yue Huang (IHEP) report on behalf of GECAM team: GECAM-B was triggered in-flight by GRB 260103A, at 2026-01-03T01:46:53.950 UTC (denoted as T0), which is also detected by SVOM/GRM (Chen-Wei Wang et.al., GCN #43314). According to the GECAM-B light curves in about 70-6000 keV, this burst mainly consists of multiple pulses with a duration (T90) of 9.0 +3.6/-7.0 s. The GECAM-B light curve can be found here: https://www.bursthub.cn//admin/static/gecambgrb260103A.png GECAM-B on-ground localization of this burst is (J2000): Ra: 269.0 deg Dec: 46.7 deg Err: 4.6 deg (1-sigma, statistical only) 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/43317. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41407] GRB 260104B: Fermi GBM Final Localization
by GCN Circulars 04 Jan '26

04 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43316 SUBJECT: GRB 260104B: Fermi GBM Final Localization DATE: 26/01/04 07:50:23 GMT FROM: Rushikesh Sonawane at IISER, TVM <rushikesh23(a)iisertvm.ac.in> The Fermi GBM team reports the detection of a likely LONG GRB "At 05:49:57.62 UT on 04 January 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260104B (trigger 789198602/260104243). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 87.42, Dec = -29.65 (J2000 degrees, equivalent to J2000 05h 49m, -29d 39'), with a statistical uncertainty of 10.28 degrees. The angle from the Fermi LAT boresight is 42 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260104243/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260104243/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260104243/…" View this GCN Circular online at https://gcn.nasa.gov/circulars/43316. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41406] GRB 260104A: Swift detection of a burst
by GCN Circulars 04 Jan '26

04 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43315 SUBJECT: GRB 260104A: Swift detection of a burst DATE: 26/01/04 05:57:24 GMT FROM: K.L. Page at U Leicester <klp5(a)leicester.ac.uk> R. Caputo (GSFC), J. J. DeLaunay (PSU), K. L. Page (U Leicester) and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift Observatory Team: At 05:37:02 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 260104A (trigger=1430212). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 337.415, -21.280 which is RA(J2000) = 22h 29m 40s Dec(J2000) = -21d 16' 48" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a complex structure with a duration of about 20 sec. The peak count rate was ~2400 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 05:38:28.9 UT, 86.1 seconds after the BAT trigger. Using promptly downlinked data we find an uncatalogued X-ray source with an enhanced position: RA, Dec 337.39898, -21.29547 which is equivalent to: RA(J2000) = 22h 29m 35.76s Dec(J2000) = -21d 17' 43.7" with an uncertainty of 2.2 arcseconds (radius, 90% containment). This location is 77 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at https://www.swift.ac.uk/sper. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (3.40 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 2.8 (+2.48/-2.16) x 10^21 cm^-2 (90% confidence). UVOT took a finding chart exposure of 150 seconds with the White filter starting 90 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers none of the XRT error circle. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.033. Burst Advocate for this burst is R. Caputo (regina.caputo AT nasa.gov) Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/) View this GCN Circular online at https://gcn.nasa.gov/circulars/43315. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41405] GRB 260103A: SVOM/GRM observation of a possible GRB
by GCN Circulars 03 Jan '26

03 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43314 SUBJECT: GRB 260103A: SVOM/GRM observation of a possible GRB DATE: 26/01/03 11:42:40 GMT FROM: Chenwei Wang at IHEP <cwwang(a)ihep.ac.cn> SVOM/GRM team: Chen-Wei Wang, Yue Huang, Shi-Jie Zheng, Shao-Lin Xiong, Shuang-Nan Zhang (IHEP) SVOM/ECLAIRs team: Frédéric Piron (LUPM) Report on behalf of the SVOM team: SVOM/GRM was triggered in-flight by a burst GRB 260103A (SVOM trigger reference: sb26010302) at 2026-01-03T01:46:54.000 UTC (T0). With the event-by-event data downloaded through the X-band ground station, the GRM light curve shows that this burst consists of multiple pulses with a T90 of 8.0 +3.8/-1.8 s in the 15-5000 keV band. The SVOM/GRM light curve can be found here: https://www.bursthub.cn//admin/static/svgrb260103A.png We note that the burst occurred near the end of a C class solar flare as detected by the GOES satellites. So the solar flare origin cannot be excluded although this burst has a typical brightness, duration, and hardness of a long GRB. 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. GRM is developed by the Institute of High Energy Physics (IHEP) of CAS. The SVOM point of contact for this burst is: Chen-Wei Wang(IHEP)(cwwang(a)ihep.ac.cn) View this GCN Circular online at https://gcn.nasa.gov/circulars/43314. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 41404] Fermi-LAT Gamma-ray Observations of IceCube-251225A
by GCN Circulars 03 Jan '26

03 Jan '26

TITLE: GCN CIRCULAR NUMBER: 43313 SUBJECT: Fermi-LAT Gamma-ray Observations of IceCube-251225A DATE: 26/01/03 09:01:01 GMT FROM: Leo Pfeiffer at University of Würzburg <pfeiffer.leo(a)gmail.com> L. Pfeiffer (Univ. of Wuerzburg), S. Buson (DESY, Univ. of Wuerzburg) and S. Garrappa (Weizmann Institute of Science) on behalf of the Fermi-LAT collaboration: We report an analysis of observations of the vicinity of the high-energy IC251225A neutrino event (GCN 43239) 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 25-12-25 at 20:14:06.80 UTC (T0) with J2000 position RA = 297.42 (+0.54, -0.49) deg, Decl. = 22.47 (+0.46, -0.48) deg 90% PSF containment (J2000). No cataloged gamma-ray sources are found within the 90% IC251225A 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 IC251225A 90% confidence localization. Assuming a power-law spectrum (photon index = 2.0 fixed) for a point source at the IC251225A best-fit position, the >100 MeV flux upper limit (95% confidence) is < 1.9e-10 ph cm^-2 s^-1 for ~17-years (2008-08-04 / T0), <1.3e-08 (<2.2e-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 analysis, the Fermi-LAT contact person is L. Pfeiffer (leonard.pfeiffer at uni-wuerzburg.de). 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/43313. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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