September 2025 - vsnet-grb-info - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-grb-info 39923] LIGO/Virgo/KAGRA S250917aq: Three counterpart neutrino candidates from IceCube neutrino searches
by GCN Circulars 17 Sep '25

17 Sep '25

TITLE: GCN CIRCULAR NUMBER: 41857 SUBJECT: LIGO/Virgo/KAGRA S250917aq: Three counterpart neutrino candidates from IceCube neutrino searches DATE: 25/09/17 21:05:39 GMT FROM: A. Zegarelli at Ruhr University Bochum <azegarelli(a)icecube.wisc.edu> IceCube Collaboration (http://icecube.wisc.edu/) reports: Searches for track-like muon neutrino events detected by IceCube consistent with the sky localization of gravitational-wave candidate S250917aq in a time range of 1000 seconds centered on the alert event time (2025-09-17 13:13:34.401 UTC to 2025-09-17 13:30:14.401 UTC) have been performed [1,2]. During this time period IceCube was collecting good quality data. Two hypothesis tests were conducted. The first search is a maximum likelihood analysis which searches for a generic point-like neutrino source coincident with the given GW skymap. The second uses a Bayesian approach to quantify the joint GW + neutrino event significance, which assumes a binary merger scenario and accounts for known astrophysical priors, such as GW source distance, in the significance estimate [3]. Three track-like events are found in spatial and temporal coincidence with the gravitational-wave candidate S250917aq calculated from the map circulated in the 4-Update notice. This represents an overall p-value of 0.0096 from the generic transient search and an overall p-value of 0.0197 for the Bayesian search. These p-values measure the consistency of the observed track-like events with the known atmospheric backgrounds for this single map (not trials corrected for multiple GW events). The most probable multi-messenger source direction based on the neutrinos and GW skymap is RA 243.72, Dec -34.23 degrees in the generic transient search. The reported p-values can differ due to the estimated distance of the GW candidate. The distance is used as a prior in the Bayesian binary merger search, while it is not taken into account in the generic transient point-like source search. The false alarm rate of these coincidences can be obtained by multiplying the p-values with their corresponding GW trigger rates. Further details are available at https://gcn.nasa.gov/missions/icecube. Additional details and updates will be posted at https://roc.icecube.wisc.edu/public/LvkNuTrackSearch/. Properties of the coincident events are shown below. | dt(s) | RA(deg) | Dec(deg) | Angular uncertainty(deg)| p-value(generic transient)| p-value(Bayesian) | |-------|----------|----------|-------------------------|---------------------------|-----------------------| | -497.79 | 228.08 | -34.97 | 0.43 | 0.0307 | null | | -82.26 | 243.67 | -34.25 | 0.43 | 0.0096 | 0.0809 | | -62.98 | 38.47 | 36.82 | 3.99 | null | 0.0302 | where: dt = Time of track event minus time of GW trigger (sec) Angular uncertainty = Angular uncertainty of track event: the radius of a circle representing 90% CL containment by area. p-value = the p-value for this specific track event from each search. Event p-values are provided when the per-event p-value is less than 0.1 in either search. 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] M. G. Aartsen et al 2020 ApJL 898 L10 [2] Abbasi et al. Astrophys.J. 944 (2023) 1, 80 [3] I. Bartos et al. 2019 Phys. Rev. D 100, 083017 View this GCN Circular online at https://gcn.nasa.gov/circulars/41857. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39922] LIGO/Virgo/KAGRA S250917aq: Updated Sky localization
by GCN Circulars 17 Sep '25

17 Sep '25

TITLE: GCN CIRCULAR NUMBER: 41856 SUBJECT: LIGO/Virgo/KAGRA S250917aq: Updated Sky localization DATE: 25/09/17 19:57:03 GMT FROM: Aditya Vijaykumar <aditya.vijaykumar(a)ligo.org> The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report: We have conducted further analysis of the LIGO Hanford Observatory (H1) and Virgo Observatory (V1) data around the time of the compact binary merger (CBC) candidate S250917aq (GCN Circular 41850). Parameter estimation has been performed using Bilby [1] and a new sky map, Bilby.multiorder.fits,0, distributed via GCN and SCiMMA notices, is available for retrieval from the GraceDB event page: https://gracedb.ligo.org/superevents/S250917aq For the Bilby.multiorder.fits,0 sky map, the 90% credible region is 5216 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 696 +/- 162 Mpc (a posteriori mean +/- standard deviation). For further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/. [1] Ashton et al. ApJS 241, 27 (2019) doi:10.3847/1538-4365/ab06fc and Morisaki et al. PRD 108, 123040 (2023) doi:10.1103/PhysRevD.108.123040 View this GCN Circular online at https://gcn.nasa.gov/circulars/41856. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39921] GRB 250916A: Glowbug gamma-ray detection
by GCN Circulars 17 Sep '25

17 Sep '25

TITLE: GCN CIRCULAR NUMBER: 41855 SUBJECT: GRB 250916A: Glowbug gamma-ray detection DATE: 25/09/17 19:22:38 GMT FROM: C.C. Cheung at Naval Research Lab <Teddy.Cheung(a)nrl.navy.mil> C.C. Cheung, R. Woolf, M. Kerr, J.E. Grove (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge, D. Kocevski (MSFC), and M.S. Briggs (UAH) report: The Glowbug gamma-ray telescope [1,2,3], operating on the International Space Station, reports the detection of GRB 250916A, which was also detected by Fermi/GBM (GCN 41839), AstroSat/CZTI (GCN 41843), and CALET (Trig ID. 1442064382). Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2025-09-16 13:33:04.840 with a duration of 64.5 s and a total significance of about 110 sigma. The light curve comprises two primary peaks at ~T0+22s and ~T0+44s. A search of the Glowbug data for the earlier, fainter emission reported in GCN 41839 by Fermi/GBM (trigger time 13:29:21) was inconclusive. The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS. Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval Research Laboratory (NRL) with support from the University of Alabama in Huntsville, USRA, and NASA MSFC. It was launched on 2023 March 15 aboard the Department of Defense Space Test Program’s STP-H9 to the ISS, and operated until 2024 April when it was put in safe storage on orbit. Glowbug was recently removed from storage and resumed operation on 2025 September 12. [1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959 [2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O [3] Woolf, R.S. et al. 2024, Proc. SPIE, 13151, id. 1315108 Distribution Statement A: Approved for public release. Distribution is unlimited. View this GCN Circular online at https://gcn.nasa.gov/circulars/41855. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39920] GRB250917B: WFST optical observations
by GCN Circulars 17 Sep '25

17 Sep '25

TITLE: GCN CIRCULAR NUMBER: 41854 SUBJECT: GRB250917B: WFST optical observations DATE: 25/09/17 19:16:36 GMT FROM: ylhua(a)pmo.ac.cn Yan-Long Hua, Bin Li, Bin-Yang Liu, Tian-Rui Sun, Jin-Jun Geng, Xue-Feng Wu, Zhi-Ping Jin, Wen Zhao, Ji-An Jiang report on behalf of the WFST team: Following the detection of GRB 250917B by Fermi GBM (Fermi GBM Team, GCN 41846) and Swift-BAT (R. Caputo, GCN 41848), we performed follow-up observations using the Wide Field Survey Telescope (WFST Collaboration; arXiv:2306.07590) at the Lenghu Astronomical Observation Base in Qinghai Province, China. Observations were performed in the g/r/i band, starting from 2025-09-17 13:15:02（UTC）to 2025-09-17 13:42:39（UTC）, with an exposure of 120s*3 for each band. The r-band stacked image reaches a limiting magnitude of 22.3 (AB). We performed image subtraction using Pan-STARRS1 (PS1) reference images, but did not find any significant optical counterpart. We also examined the Swift-XRT (J.A. Kennea, GCN 41851) sources within the GRB error region: Source 1 is located near the center of a galaxy, making it difficult to justify an optical counterpart. Source 5 and Source 6 show no detectable optical counterparts in our images. These results suggest that no clear optical afterglow was detected at the positions of the X-ray sources within our observation limits. We thank the WFST staff for supporting these observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/41854. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39919] GRB 250916A: Swift ToO observations
by GCN Circulars 17 Sep '25

17 Sep '25

TITLE: GCN CIRCULAR NUMBER: 41853 SUBJECT: GRB 250916A: Swift ToO observations DATE: 25/09/17 19:02:32 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 Fermi/GBM-detected event GRB 250916A. Automated analysis of the XRT data will be presented online at https://www.swift.ac.uk/ToO_GRBs/00021859 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 Fermi/GBM 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/41853. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39918] GRB 250917B: Fermi GBM Observation
by GCN Circulars 17 Sep '25

17 Sep '25

TITLE: GCN CIRCULAR NUMBER: 41852 SUBJECT: GRB 250917B: Fermi GBM Observation DATE: 25/09/17 18:53:07 GMT FROM: Rushikesh Digambar Sonawane PHD231014 at IISER, TVM <rushikesh23(a)iisertvm.ac.in> R. Sonawane (IISER, TVM) and C. Meegan (UAH) report on behalf ofthe Fermi Gamma-ray Burst Monitor Team:"At 06:27:44.33 UT on 17 September 2025, the Fermi Gamma-ray Burst Monitor (GBM)triggered and located GRB 250917B (trigger 779783269/250917269).which was also detected by Swift BAT (R. Caputo et al. 2025, GCN 41848).The Fermi GBM on-ground location is consistent with the Swift BAT position.The angle from the Fermi LAT boresight is 48 degrees.The GBM light curve consists of a single emission episode with a duration (T90)of about 0.2 s (50-300 keV). The time-averaged spectrumfrom T0-0.2 to T0+0.3 s is best fit bya power law function with an exponential high-energy cutoff.The power law index is -1 +/- 0.2 and the cutoff energy,parameterized as Epeak, is 120 +/- 20 keV.The event fluence (10-1000 keV) in this time interval is(3.2 +/- 0.3)E-07 erg/cm^2. The 64-ms peak photon flux measuredstarting from T0+0.0 s in the 10-1000 keV band is 24 +/- 2 ph/s/cm^2.The spectral analysis results presented above are preliminary;final results will be published in the GBM GRB Catalog:https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.htmlFor Fermi GBM data and info, please visit the official Fermi GBM Support Page:https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/" View this GCN Circular online at https://gcn.nasa.gov/circulars/41852. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39917] GRB 250917B: Swift-XRT observations
by GCN Circulars 17 Sep '25

17 Sep '25

TITLE: GCN CIRCULAR NUMBER: 41851 SUBJECT: GRB 250917B: Swift-XRT observations DATE: 25/09/17 17:14:55 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> J.A. Kennea (PSU), A.P. Beardmore (U. Leicester), J.P. Osborne (U. Leicester), B. Sbarufatti (INAF-OAB), C. Salvaggio (INAF-OAB), M. Ferro (INAF-OAB), D.N. Burrows (PSU), S. Lanava (PSU) and P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team: We have analysed 5.5 ks of Photon Counting (PC) mode XRT data for GRB 250917B, collected between T0+142 s and T0+28.4 ks. Three uncatalogued X-ray sources have been detected within the estimated 3-sigma Swift-BAT error region (296 arcsec), 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): 291.3458 = 19h 25m 23.00s Dec (J2000.0): +11.1151 = +11d 06' 54.5" Error: 5.5 arcsec (radius, 90% conf. [Enhanced position]) Count-rate: (5.5 [+1.3, -1.2])e-3 ct s^-1 Distance: 113 arcsec from Swift-BAT position. Flux: (1.26 [+0.30, -0.28])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV) Source 5: RA (J2000.0): 291.3929 = 19h 25m 34.30s Dec (J2000.0): +11.0748 = +11d 04' 29.2" Error: 7.7 arcsec (radius, 90% conf.) Count-rate: (4.6 [+5.4, -3.9])e-4 ct s^-1 Distance: 147 arcsec from Swift-BAT position. Source 6: RA (J2000.0): 291.4312 = 19h 25m 43.49s Dec (J2000.0): +11.1014 = +11d 06' 05.0" Error: 8.3 arcsec (radius, 90% conf.) Count-rate: (7.4 [+6.4, -4.8])e-4 ct s^-1 Distance: 192 arcsec from Swift-BAT position. Flux: (1.47 [+1.27, -0.95])e-12 erg cm^-2 s^-1 (observed, 0.3-10 keV) Three uncatalogued sources were also detected too far from the GRB position to be likely afterglow candidates. 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/01350381. This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/41851. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39916] LIGO/Virgo/KAGRA S250917aq: Identification of a GW compact binary merger candidate
by GCN Circulars 17 Sep '25

17 Sep '25

TITLE: GCN CIRCULAR NUMBER: 41850 SUBJECT: LIGO/Virgo/KAGRA S250917aq: Identification of a GW compact binary merger candidate DATE: 25/09/17 14:18:25 GMT FROM: daniela.pascucci(a)ugent.be The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report: We identified the compact binary merger candidate S250917aq during real-time processing of data from LIGO Hanford Observatory (H1) and Virgo Observatory (V1) at 2025-09-17 13:21:54.401 UTC (GPS time: 1442150532.401). The candidate was found by the GstLAL [1] analysis pipeline. S250917aq is an event of interest because its false alarm rate, as estimated by the online analysis, is 1.1e-13 Hz, or about one in 1e5 years. The event's properties can be found at this URL: https://gracedb.ligo.org/superevents/S250917aq The classification of the GW signal, in order of descending probability, is BBH (>99%), NSBH (<1%), Terrestrial (<1%), or BNS (<1%). Assuming the candidate is astrophysical in origin, the probability that at least one of the compact objects is consistent with a neutron star mass (HasNS) is <1%. [2] Using the masses and spins inferred from the signal, the probability of matter outside the final compact object (HasRemnant) is <1%. [2] Both HasNS and HasRemnant consider the support of several neutron star equations of state for maximum neutron star mass. The probability that either of the binary components lies between 3 and 5 solar masses (HasMassGap) is 3%. The source chirp mass falls with highest probability in the bin (5.5, 11.0) solar masses, assuming the candidate is astrophysical in origin. Two sky maps are available at this time and can be retrieved from the GraceDB event page: * bayestar.multiorder.fits,0, an initial localization generated by BAYESTAR [3], distributed via GCN and SCiMMA notices about 25 seconds after the candidate event time. * bayestar.multiorder.fits,1, an initial localization generated by BAYESTAR [3], distributed via GCN and SCiMMA notices about 5 minutes after the candidate event time. The preferred sky map at this time is bayestar.multiorder.fits,1. For the bayestar.multiorder.fits,1 sky map, the 90% credible region is 5646 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 687 +/- 182 Mpc (a posteriori mean +/- standard deviation). For further information about analysis methodology and the contents of this alert, refer to the LIGO/Virgo/KAGRA Public Alerts User Guide https://emfollow.docs.ligo.org/. [1] Tsukada et al. PRD 108, 043004 (2023) doi:10.1103/PhysRevD.108.043004 and Ewing et al. PRD 109, 042008 (2024) doi:10.1103/PhysRevD.109.042008 [2] Chatterjee et al. ApJ 896, 54 (2020) doi:10.3847/1538-4357/ab8dbe [3] Singer & Price PRD 93, 024013 (2016) doi:10.1103/PhysRevD.93.024013 View this GCN Circular online at https://gcn.nasa.gov/circulars/41850. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39915] Fermi GRB 250917B: Global MASTER-Net observations report
by GCN Circulars 17 Sep '25

17 Sep '25

TITLE: GCN CIRCULAR NUMBER: 41849 SUBJECT: Fermi GRB 250917B: Global MASTER-Net observations report DATE: 25/09/17 12:31:52 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 (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB 250917B ( Fermi GBM team, GCN 41846) errorbox 21352 sec after notice time and 21386 sec after trigger time at 2025-09-17 12:24:10 UT, with upper limit up to 13.2 mag. Observations started at twilight. The observations began at zenith distance = 22 deg. The sun altitude is -11.2 deg. The galactic latitude b = 19 deg., longitude l = 57 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2993668 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 21416 | 2025-09-17 12:24:10 | MASTER-Tunka | (18h 22m 39.27s , +29d 57m 54.1s) | C | 60 | 13.2 | 21498 | 2025-09-17 12:25:32 | MASTER-Tunka | (18h 19m 56.75s , +28d 02m 47.7s) | C | 60 | 13.0 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. View this GCN Circular online at https://gcn.nasa.gov/circulars/41849. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 39914] GRB 250917B: Swift detection of a short burst
by GCN Circulars 17 Sep '25

17 Sep '25

TITLE: GCN CIRCULAR NUMBER: 41848 SUBJECT: GRB 250917B: Swift detection of a short burst DATE: 25/09/17 06:48:14 GMT FROM: K.L. Page at U Leicester <klp5(a)leicester.ac.uk> R. Caputo (GSFC), C. Gronwall (PSU) and K. L. Page (U Leicester) report on behalf of the Neil Gehrels Swift Observatory Team: At 06:27:44 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 250917B (trigger=1350381). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 291.378, +11.113 which is RA(J2000) = 19h 25m 31s Dec(J2000) = +11d 06' 48" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a short, single peaked structure with a duration of about 0.5 sec. The peak count rate was ~8000 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 06:29:58.5 UT, 134.2 seconds after the BAT trigger. No source was detected in 681 s of promptly downlinked data. We are waiting for the full dataset to detect and localise the XRT counterpart. UVOT took a finding chart exposure of 150 seconds with the White filter starting 138 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 25% of the BAT error circle. The typical 3-sigma upper limit has been about 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the BAT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the large, but uncertain, extinction expected. 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/41848. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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