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

[vsnet-grb-info 38530] GRB 250520A: DDOTI Optical Upper Limit
by GCN Circulars 20 May '25

20 May '25

TITLE: GCN CIRCULAR NUMBER: 40498 SUBJECT: GRB 250520A: DDOTI Optical Upper Limit DATE: 25/05/20 10:26:32 GMT FROM: Rosa L. Becerra at Tor Vergata, Roma <rosa.becerra(a)roma2.infn.it> Rosa L. Becerra (U Roma), Sahil Atri (U Roma), Alan M. Watson (UNAM), Camila Angulo Valdez (UNAM), Nat Butler (ASU), Simone Dichiara (Penn State University), Tsvetelina Dimitrova (ASU), Alexander Kutyrev (GSFC/UMD), William H. Lee (UNAM), Océlotl López (UNAM), Margarita Pereyra (UNAM) and Eleonora Troja (U Roma) report: We observed the field of the GRB 250520A detected by Swift/BAT (Eyles-Ferris et al., GCN Circ. 40491), SVOM/GRM (SVOM/GRM team, GCN Circ. 40495) and AstroSat/CZTI (Tembhurnikar et al., GCN Circ. 40497) with the DDOTI/OAN wide-field imager at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir (http://ddoti.astroscu.unam.mx) on the night of 2025-05-20 UTC. DDOTI observed the field of GRB 250520B from 06:59 UTC to 08:48 UTC (from T+4.3 h to T+6.2 h after the trigger) and obtained a total exposure of 22 minutes, alternating with other scientific programs. Comparing our observations to the USNO-B1 and Pan-STARRS PS1 DR2 catalogues, we detect no any uncatalogued source at the position reported by Fermi GBM Team, GCN Circ. 40314) down to a 3-sigma limiting AB magnitude of: w > 20.5 This value is consistent with the reported by GOTO (Kumar et al., GCN Circ. 40493) These values are not corrected for the Galactic extinction. We thank the staff of the Observatorio Astronómico Nacional on the Sierra of San Pedro Mártir. View this GCN Circular online at https://gcn.nasa.gov/circulars/40498. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38529] GRB 250520A: AstroSat CZTI detection of a short burst
by GCN Circulars 20 May '25

20 May '25

TITLE: GCN CIRCULAR NUMBER: 40497 SUBJECT: GRB 250520A: AstroSat CZTI detection of a short burst DATE: 25/05/20 09:34:08 GMT FROM: Gaurav Waratkar at IIT Bombay <gauravwaratkar(a)iitb.ac.in> M. Tembhurnikar (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration: Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a short duration GRB 250520A which was also detected by Swift/BAT (Eyles-Ferris et al., GCN Circ. 40491), SVOM/GRM (SVOM/GRM team, GCN Circ. 40495), and CALET/GBM (Trigger ID 1431743946). The source was clearly detected in the CZT detectors in the 20-200 keV energy range. The light curve peaks at 2025-05-20 02:42:16.94 UTC. The measured peak count rate associated with the burst is 1106 (+638, -259) counts/s above the background in the combined data of two quadrants (out of four), with a total of 73 (+23, -23) counts. The local mean background count rate was 141 (+22, -43) counts/s. Using cumulative rates, we measure a T90 of 0.15 (+0.03, -0.04) s. The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2025-05-20 02:42:16.12 UTC. The measured peak count rate associated with the burst is 674 (+70, -74) counts/s above the background in the combined data of all quadrants, with a total of 640 (+115, -115) counts. The local mean background count rate was 1161 (+9, -10) counts/s. Due to the intrinsic 1 s binning of veto data, we cannot reliably estimate a T90 from it. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project. CZTI GRB detections are reported regularly on the payload site at: http://astrosat.iucaa.in/czti/?q=grb View this GCN Circular online at https://gcn.nasa.gov/circulars/40497. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38528] GRB 250516B: GRBAlpha detection
by GCN Circulars 20 May '25

20 May '25

TITLE: GCN CIRCULAR NUMBER: 40496 SUBJECT: GRB 250516B: GRBAlpha detection DATE: 25/05/20 08:49:07 GMT FROM: Marianna Dafčíková at Masaryk University <500025(a)mail.muni.cz> M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner (Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Duriskova, M. Kolar, L. Szakszonova, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Povalac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), T. Enoto (Kyoto U.), Zs. Frei (Eotvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshima U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration. The long-duration GRB 250516B (GECAM-B detection: GCN 40469; NuSTAR detection: GCN 40484; Insight-HXMT/HE detection: GCN 40489; Wind/Konus detection trigger at 2025-05-16 06:31:32.766 UTC) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023, A&A, 677, 40; https://ui.adsabs.harvard.edu/abs/2023A%26A...677A..40P/abstract) The detection was confirmed at the peak time 2025-05-16 06:31:54.3 UTC. The T90 duration measured by GRBAlpha is 40 s and the overall significance during T90 reaches 83 sigma. The light curve obtained by GRBAlpha is available here: https://grbalpha.konkoly.hu/static/share/GRB250516B_GCN.pdf All GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/ GRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume. View this GCN Circular online at https://gcn.nasa.gov/circulars/40496. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38527] GRB 250520A: SVOM/GRM observation
by GCN Circulars 20 May '25

20 May '25

TITLE: GCN CIRCULAR NUMBER: 40495 SUBJECT: GRB 250520A: SVOM/GRM observation DATE: 25/05/20 08:40:08 GMT FROM: Chenwei Wang at IHEP <cwwang(a)ihep.ac.cn> SVOM/GRM team: Chen-Wei Wang, Wen-Jun Tan Shi-Jie Zheng, Yue Huang, Shao-Lin Xiong, Shuang-Nan Zhang (IHEP) SVOM/ECLAIRs team: Stéphane Schanne (CEA), Marius Brunet (IRAP) report on behalf of the SVOM team: SVOM/GRM was triggered in-flight by a short burst GRB 250520A (SVOM trigger reference: sb25052002) at 2025-05-20T02:42:16.900 UTC (T0), which is also detected by Swift/BAT (R. A. J. Eyles-Ferris et al., GCN #40491). With the event-by-event data downloaded through the X-band ground station, the GRM light curve shows that this burst consists of a single pulse with a T90 of 0.34 +0.12/-0.16 s in the 15-5000 keV band. The SVOM/GRM light curve can be found here: https://www.bursthub.cn//admin/static/svgrb250520A.png In addition, the position of this burst, as determined by Swift (RA= 282.268, Dec=-11.847, GCN #40491), is located at about 101 degrees from the SVOM optical axis. ECLAIRs was not colecting data at the time of the burst. With this localization, the time-averaged spectrum from T0-0.1 to T0+0.2 s is best fitted by a power law function with an exponential high-energy cutoff. The power law index is -0.64 +/-0.13 and the cutoff energy, parameterized as Epeak, is 1080 +283/-151 keV. The event fluence (10-1000 keV) in this time interval is (2.34 +0.15/-0.14)E-06 erg/cm^2. The localization of GRB 250505B in the 'Amati' relation diagram is shown at: https://www.bursthub.cn//admin/static/grb250520A_amati.png 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/40495. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38526] GRB 250520A: Enhanced Swift-XRT position
by GCN Circulars 20 May '25

20 May '25

TITLE: GCN CIRCULAR NUMBER: 40494 SUBJECT: GRB 250520A: Enhanced Swift-XRT position DATE: 25/05/20 08:03:58 GMT FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk> M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team. Using 1223 s of XRT Photon Counting mode data and 2 UVOT images for GRB 250520A, 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 = 282.28575, -11.86913 which is equivalent to: RA (J2000): 18h 49m 8.58s Dec (J2000): -11d 52' 08.9" with an uncertainty of 2.5 arcsec (radius, 90% confidence). This position may be improved as more data are received. The latest position can be viewed at http://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/40494. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38525] GRB 250520A: GOTO optical upper limit
by GCN Circulars 20 May '25

20 May '25

TITLE: GCN CIRCULAR NUMBER: 40493 SUBJECT: GRB 250520A: GOTO optical upper limit DATE: 25/05/20 03:28:58 GMT FROM: Amit Kumar at Royal Holloway - UoL/ U of Warwick, UK <amitkundu515(a)gmail.com> A. Kumar, B. P. Gompertz, R. Starling, K. Ackley, M. J. Dyer, J. Lyman, K. Ulaczyk, D. O'Neill, B. Godson, D. Steeghs, D. K. Galloway, V. Dhillon, P. O'Brien, G. Ramsay, K. Noysena, R. Kotak, R. P. Breton, L. K. Nuttall, and J. Casares report on behalf of the GOTO collaboration: The Gravitational-wave Optical Transient Observer (GOTO, Steeghs et al. 2022; Dyer et al. 2024) performed a targeted observation in response to Swift/Burst Alert Telescope (BAT)-triggered GRB 250520A (Eyles-Ferris et al. GCN 40491) at 2025-05-20 UT 02:46:48 (4.54 minutes after trigger). The observation consisted of 4x90s exposures in the GOTO L-band (400-700 nm). Images were processed immediately after acquisition using the GOTO pipeline. Difference imaging was performed using deeper template observations of the same pointings. No optical counterpart is detected within the Swift/XRT 90% localisation region (Evans et al. GCN 40492) to a 3-sigma limiting magnitude of L > 19.86 (AB). Magnitudes were calibrated using ATLAS-REFCAT2 (Tonry et al. 2018) and are not corrected for Galactic extinction. GOTO (https://goto-observatory.org) is a network of telescopes that is principally funded by the STFC and operated at the Roque de los Muchachos Observatory on La Palma, Spain, and Siding Spring Observatory in NSW, Australia, on behalf of a consortium including the University of Warwick, Monash University, Armagh Observatory & Planetarium, the University of Leicester, the University of Sheffield, the National Astronomical Research Institute of Thailand (NARIT), the University of Turku, the University of Portsmouth, the University of Manchester and the Instituto de Astrofisica de Canarias (IAC). View this GCN Circular online at https://gcn.nasa.gov/circulars/40493. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38524] GRB 250520A: Prompt enhanced Swift-XRT position
by GCN Circulars 20 May '25

20 May '25

TITLE: GCN CIRCULAR NUMBER: 40492 SUBJECT: GRB 250520A: Prompt enhanced Swift-XRT position DATE: 25/05/20 03:19:49 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-XRT team: Using 1.2 ks of promptly downlinked XRT event data for GRB 250520A, we find an enhanced XRT position of the afterglow: RA, Dec: 282.28613, -11.86896 which is equivalent to: RA (J2000) = 18 49 08.67 Dec (J2000) = -11 52 08.3 with an uncertainty of 2.0 arcseconds (radius, 90% confidence). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/1315630. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177). This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/40492. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38523] GRB 250520A: Swift detection of a burst
by GCN Circulars 20 May '25

20 May '25

TITLE: GCN CIRCULAR NUMBER: 40491 SUBJECT: GRB 250520A: Swift detection of a burst DATE: 25/05/20 02:59:58 GMT FROM: K.L. Page at U Leicester <klp5(a)leicester.ac.uk> R. A. J. Eyles-Ferris (U Leicester), N. P. M. Kuin (UCL-MSSL), A. Y. Lien (U Tampa), M. J. Moss (GSFC) and K. L. Page (U Leicester) report on behalf of the Neil Gehrels Swift Observatory Team: At 02:42:16.84 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 250520A (trigger=1315630). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 282.268, -11.847 which is RA(J2000) = 18h 49m 04s Dec(J2000) = -11d 50' 49" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a short burst with a duration of about 1 sec. The peak count rate was ~10,000 counts/sec (15-350 keV), at ~0 sec after the trigger. The XRT began observing the field at 02:44:40.8 UT, 144.1 seconds after the BAT trigger. Using promptly downlinked data we find a fading, uncatalogued X-ray source located at RA, Dec 282.28588, -11.86811 which is equivalent to: RA(J2000) = 18h 49m 08.61s Dec(J2000) = -11d 52' 05.2" with an uncertainty of 3.6 arcseconds (radius, 90% containment). This location is 98 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 (3.68 x 10^21 cm^-2, Willingale et al. 2013), with an excess column of 8 (+6.16/-4.83) x 10^21 cm^-2 (90% confidence). UVOT took a finding chart exposure of 150 seconds with the White filter starting 148 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 100% of the XRT error circle. Because of the density of catalogued stars, further analysis is required to report an upper limit for any afterglow in the sub-image. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. Because of the density of catalogued stars, further analysis is required to report an upper limit for any afterglow in the region. No correction has been made for the large, but uncertain, extinction expected. Burst Advocate for this burst is R. A. J. Eyles-Ferris (raje1 AT leicester.ac.uk). 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/40491. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38522] Swift GRB250520.11: Global MASTER-Net observations report
by GCN Circulars 20 May '25

20 May '25

TITLE: GCN CIRCULAR NUMBER: 40490 SUBJECT: Swift GRB250520.11: Global MASTER-Net observations report DATE: 25/05/20 02:56:51 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 (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the Swift GRB250520.11 (trigger No 1315630,18h 49m 04.32s , -11d 50m 49.2s, R=0.05) errorbox 23 sec after notice time and 46 sec after trigger time at 2025-05-20 02:43:03 UT, with upper limit up to 17.0 mag. The observations began at zenith distance = 25 deg. The sun altitude is -33.7 deg. The galactic latitude b = -5 deg., longitude l = 22 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2875870 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 52 | MASTER-SAAO | C | 10 | 16.3 | 80 | MASTER-SAAO | C | 10 | 16.3 | 115 | MASTER-SAAO | C | 20 | 16.4 | 159 | MASTER-SAAO | C | 30 | 16.7 | 213 | MASTER-SAAO | C | 40 | 16.7 | 277 | MASTER-SAAO | C | 50 | 16.7 | 351 | MASTER-SAAO | C | 60 | 17.0 | 430 | MASTER-SAAO | C | 60 | 16.9 | 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/40490. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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[vsnet-grb-info 38521] GRB 250516B: Insight-HXMT detection
by GCN Circulars 19 May '25

19 May '25

TITLE: GCN CIRCULAR NUMBER: 40489 SUBJECT: GRB 250516B: Insight-HXMT detection DATE: 25/05/19 12:37:22 GMT FROM: Chenwei Wang at IHEP <cwwang(a)ihep.ac.cn> Chen-Wei Wang, Shao-Lin Xiong, and Jin-Peng Zhang report on behalf of the Insight-HXMT team: At 2025-05-16T06:31:34.7 (T0), Insight-HXMT/HE detected the bright long burst GRB 250516B, which is also detected by GECAM-B (Wang et al., GCN #40469), NuSTAR (B. Grefenstette et al., GCN #40484) and Konus-Wind. The Insight-HXMT/HE light curve mainly consists of multiple pulses with a T90 of 39.6 +0.3/-0.2 s. The 1s peak rate, measured from T0+13.1 s, is 27175 cnts/sec. The total counts from this burst is 423316 counts. The HXMT/HE light curve can be found here: https://www.bursthub.cn//admin/static/hxmtgrb250516B.png All measurements above are made with the CsI detectors operating in the regular mode with the energy range of about 30-1000 keV (deposited energy). Only gamma-rays with energy greater than about 200 keV can penetrate the spacecraft and leave signals in the CsI detectors installed inside of the telescope. Insight-HXMT is the first Chinese space X-ray telescope, which was funded jointly by the China National Space Administration (CNSA) and the Chinese Academy of Sciences (CAS). More information about it could be found at: http://www.hxmt.org. View this GCN Circular online at https://gcn.nasa.gov/circulars/40489. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

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