September 2024 - vsnet-grb-info - ooruri.kusastro.kyoto-u.ac.jp

[vsnet-grb-info 35570] AMON NuEM 240926A: Swift XRT Follow-up
by GCN Circulars 30 Sep '24

30 Sep '24

TITLE: GCN CIRCULAR NUMBER: 37643 SUBJECT: AMON NuEM 240926A: Swift XRT Follow-up DATE: 24/09/30 20:37:19 GMT FROM: Hugo Ayala at Pennsylvania State University <hgayala(a)psu.edu> The AMON group reports: We requested follow-up time for the AMON alert NuEM 240926A (GCN ). The follow-up looked for any x-ray sources inside the 90% region of the AMON alert: RA (J2000): 149.97 deg Dec (J2000): 46.22 deg Location uncertainty (90% containment): 0.41 deg We used the online analysis software in www.swift.ac.uk Swift-XRT started the follow-up on 2024-09-26 at 21:33:07 UT, which is ~2.5hrs after the AMON alert. It collected 6,745 seconds of photon counting (PC) mode data in a 7-tile mosaic. Four uncatalogued sources were detected. Source 1: RA: 09h 59m 9.62s (149.790 deg) Dec: 46deg 00’ 15.2” (46.004 deg) Error: 5.6” Source 2: RA: 10h 00m 15.04s (150.063 deg) Dec: 45d 58’ 49.2” (45.980 deg) Error: 5.0” Source 3: RA: 10h 2m 35.8s (150.649 deg) Dec: 46d 21’ 43.8” (46.362 deg) Error: 6.0” Source 4: RA: 9h 58m 18.95s (149.578 deg) Dec: 46d 8’ 20.5” (46.139 deg) Error: 9.0” The 4FGL J0959.6+4606, located at (149.89, 46.10), is close to source 1, which is inside the 4FGL PSF region (0.2 deg above 10GeV). This 4FGL source has been considered as the counterpart of the radio-galaxy 2MASX J09591976+4603515 with coordinates (149.88,46.10) (Pena-Herazo et al. 2021). However, we find here that Source 1 from the XRT follow-up is on top of the Seyfert 1 Galaxy SDSSJ095909.51+460014.3 (149.789,46.003). We requested one more follow-up on Source 1 from XRT. We will report on it after observations are done. Source detection is based on Evans, et al. 2020 ApJ Supplemental, 247 AMON seeks to perform a real-time correlation analysis of the high-energy signals across all known astronomical messengers. More information about AMON can be found in https://www.amon.psu.edu/ Information on the IceCube collaboration: http://icecube.wisc.edu/ Information on the HAWC collaboration: https://www.hawc-observatory.org View this GCN Circular online at https://gcn.nasa.gov/circulars/37643. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 35569] GRB 240929A : Leavitt Observatory optical upper limit
by GCN Circulars 30 Sep '24

30 Sep '24

TITLE: GCN CIRCULAR NUMBER: 37642 SUBJECT: GRB 240929A : Leavitt Observatory optical upper limit DATE: 24/09/30 19:52:37 GMT FROM: leavittob(a)gmail.com L. Moretti and E. Pavoni (Leavitt Observatory, Italy), Members of: GRB/UAI - Gamma ray Burst section of Unione Astrofili Italiani. ATA - Associazione Tuscolana di Astronomia. In a large collaboration with: M.G. Dainotti (National Astronomical Observatory of Japan), Y. Niino (Tokyo University, Institute of Astronomy), K. Kalinowski (Aarhus University, Department of Physics and Astronomy), B. De Simone (Universita' degli Studi Di Salerno) report: We imaged the field of GRB 240929A detected by INTEGRAL (Fermi GBM Team, GCN 37627; Lipunov et al., GCN 37628; Preis et al., GCN 37629; Mereghetti et al., GCN 37630), with the RC telescope (D=250 mm, F/D=8) of Leavitt Observatory, Italy. The observations started at 20:17:40 UT on 2024-09-29, i.e. about 27 min. after the INTEGRAL trigger, at the following position: RA(J2000) = 00h 09m 42s Dec(J2000) = 74° 49' 39" Weather conditions were good. We co-added 27 exposures of 120 sec each (total 54 min). We did not found any optical counterpart in the error box (2 arcmin) of INTEGRAL, with the following upper limit: Start End Limit 2024-09-29T20:17:40 2024-09-29T21:10:53 > 20.9 Magnitudes were estimated with the BP-band of Gaia DR3 catalogue (*) and are not corrected for galactic dust extinction. Reference: https://leavittobservatory.altervista.org The message may be cited. (*) https://gea.esac.esa.int/archive/documentation/GEDR3/Data_processing/chap_c… View this GCN Circular online at https://gcn.nasa.gov/circulars/37642. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 35568] Fermi GRB 240930B: Global MASTER-Net observations report
by GCN Circulars 30 Sep '24

30 Sep '24

TITLE: GCN CIRCULAR NUMBER: 37641 SUBJECT: Fermi GRB 240930B: Global MASTER-Net observations report DATE: 24/09/30 18:45:58 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov(a)xray.sai.msu.ru> V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko, G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gress, N.M. Budnev, O.Ershova (Irkutsk State University, API), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich (Blagoveschensk Educational State University) 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) started inspect of the Fermi GRB 240930B ( Fermi GBM team, GCN 37640) errorbox 118 sec after notice time and 151 sec after trigger time at 2024-09-30 17:20:33 UT, with upper limit up to 15.9 mag. Observations started at twilight. The observations began at zenith distance = 75 deg. The sun altitude is -9.4 deg. The galactic latitude b = -3 deg., longitude l = 83 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2620328 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 166 | 2024-09-30 17:20:33 | MASTER-SAAO | (20h 49m 45.26s , +39d 39m 45.0s) | C | 30 | 14.2 | 211 | 2024-09-30 17:20:33 | MASTER-SAAO | (20h 49m 45.27s , +39d 39m 45.1s) | C | 120 | 15.2 | Coadd 220 | 2024-09-30 17:21:22 | MASTER-SAAO | (20h 49m 45.45s , +39d 39m 47.8s) | C | 40 | 13.9 | 284 | 2024-09-30 17:22:21 | MASTER-SAAO | (20h 49m 45.71s , +39d 39m 51.7s) | C | 50 | 15.1 | 358 | 2024-09-30 17:23:30 | MASTER-SAAO | (20h 49m 45.95s , +39d 39m 55.2s) | C | 60 | 15.4 | 604 | 2024-09-30 17:27:36 | MASTER-SAAO | (20h 54m 11.43s , +40d 26m 14.9s) | C | 60 | 14.0 | 664 | 2024-09-30 17:27:36 | MASTER-SAAO | (20h 54m 11.43s , +40d 26m 14.9s) | C | 180 | 15.3 | Coadd 684 | 2024-09-30 17:28:55 | MASTER-SAAO | (20h 54m 11.69s , +40d 26m 17.7s) | C | 60 | 14.6 | 763 | 2024-09-30 17:30:14 | MASTER-SAAO | (20h 54m 11.95s , +40d 26m 20.0s) | C | 60 | 14.7 | 842 | 2024-09-30 17:31:33 | MASTER-SAAO | (20h 54m 12.22s , +40d 26m 22.3s) | C | 60 | 15.3 | 1181 | 2024-09-30 17:37:12 | MASTER-SAAO | (20h 44m 39.54s , +40d 45m 14.1s) | C | 60 | 15.8 | 1260 | 2024-09-30 17:38:32 | MASTER-SAAO | (20h 55m 17.13s , +40d 46m 14.7s) | C | 60 | 15.9 | 1578 | 2024-09-30 17:43:50 | MASTER-SAAO | (20h 49m 30.74s , +38d 51m 18.7s) | C | 60 | 15.3 | 1658 | 2024-09-30 17:45:09 | MASTER-SAAO | (20h 59m 44.68s , +38d 52m 04.7s) | C | 60 | 15.1 | 1737 | 2024-09-30 17:46:29 | MASTER-SAAO | (20h 41m 17.74s , +42d 41m 20.3s) | C | 60 | 14.8 | 1816 | 2024-09-30 17:47:48 | MASTER-SAAO | (20h 51m 56.45s , +42d 39m 51.8s) | C | 60 | 15.2 | 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/37641. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 35567] GRB 240930B: Fermi GBM Final Real-time Localization
by GCN Circulars 30 Sep '24

30 Sep '24

TITLE: GCN CIRCULAR NUMBER: 37640 SUBJECT: GRB 240930B: Fermi GBM Final Real-time Localization DATE: 24/09/30 17:28:37 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply(a)GIOC.nsstc.nasa.gov> The Fermi GBM team reports the detection of a likely LONG GRB At 17:18:02 UT on 30 Sep 2024, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 240930B (trigger 749409487.116994 / 240930721). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 313.7, Dec = 40.8 (J2000 degrees, equivalent to J2000 20h 54m, 40d 47'), with a statistical uncertainty of 1.8 degrees. The angle from the Fermi LAT boresight is 110.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240930721/… The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240930721/… The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240930721/… View this GCN Circular online at https://gcn.nasa.gov/circulars/37640. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 35566] IPN triangulation of GRB 240926A
by GCN Circulars 30 Sep '24

30 Sep '24

TITLE: GCN CIRCULAR NUMBER: 37639 SUBJECT: IPN triangulation of GRB 240926A DATE: 24/09/30 15:36:50 GMT FROM: Dmitry Svinkin at Ioffe Institute <svinkin(a)mail.ioffe.ru> A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin on behalf of the HEND/Mars Odyssey team, D. Svinkin, D. Frederiks, A. Ridnaia, A. Lysenko, and T. Cline on behalf of the Konus-Wind team, E. Burns, on behalf of the IPN, E. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, and W. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr, and A.S. Gardner on on behalf of the GRS-Odyssey GRB team, report: The long-duration GRB 240926A (SVOM-GRM detection: Zhang et al., GCN 37616) was detected by SVOM (GRM), Konus-Wind, INTEGRAL (SPI-ACS), and Mars-Odyssey (HEND) at about 42164 s UT (11:42:44). We have triangulated it to a preliminary, 3 sigma error box whose coordinates are: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 240.361 (16h 01m 27s) +45.364 (+45d 21' 52") Corners: 241.263 (16h 05m 03s) +45.816 (+45d 48' 59") 241.214 (16h 04m 51s) +45.898 (+45d 53' 53") 239.475 (15h 57m 54s) +44.903 (+44d 54' 12") 239.526 (15h 58m 06s) +44.822 (+44d 49' 21") --------------------------------------------- The error box area is 483 sq. arcmin, and its maximum dimension is 1.6 deg (the minimum one is 5.1 arcmin). The Sun distance was 68 deg. The IPN localization is consistent with, but reduces the area of, the SVOM-GRM localization (GCN 37616). This localization may be improved. A triangulation map and HEALPix FITS file are posted at http://www.ioffe.ru/LEA/GRBs/GRB240926_T42164/IPN The HEALPix triangulation map is the multi-order HEALPix in units of probability density. The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular. View this GCN Circular online at https://gcn.nasa.gov/circulars/37639. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 35565] GRB 240825A: LBT optical observations
by GCN Circulars 30 Sep '24

30 Sep '24

TITLE: GCN CIRCULAR NUMBER: 37638 SUBJECT: GRB 240825A: LBT optical observations DATE: 24/09/30 14:36:08 GMT FROM: Elisabetta Maiorano at INAF <elisabetta.maiorano(a)inaf.it> E. Maiorano, A. Rossi, E. Palazzi (INAF-OAS), D. Paris (OA Roma), D. B. Malesani (DAWN/NBI and Radboud Univ.), and M. De Pasquale (Univ. of Messina), report on behalf of the CIBO collaboration: We observed the field of GRB 240825A (Fermi GBM team, GCN 37273; Gupta et al., GCN 37274) with the LBC camera mounted on LBT (Mt. Graham, AZ, USA) in r’ and z’ bands (45 min exposure time per filter) approximately at midtime 05:55:00 UT on 2024-09-12 (17.6 days after the burst). The optical transient (Jiang et al. GCN 37275; Dutton et al. GCN 37276; Odeh et al. GCN 37277; Zhang et al. GCN 37278; Li et al. GCN 37280; Izzo & Malesani, GCN 37287; Lipunov et al. GCN 37289; Leonini et al. GCN 37291; Wu et al. GCN 37292; Brivio et al. GCN 32795; Odeh, GCN 37299) is well detected in r’ and z’ bands. Using PSF photometry, we measure a preliminary AB magnitude of r'=22.8+-0.1, calibrated against Pan-STARRS field stars, and not corrected for the foreground Galactic extinction. We acknowledge the excellent support from the LBTO and LBTB staff, particularly Jan Snigula in obtaining these observations. View this GCN Circular online at https://gcn.nasa.gov/circulars/37638. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 35564] GRB 240928A: SVOM/GRM observation
by GCN Circulars 30 Sep '24

30 Sep '24

TITLE: GCN CIRCULAR NUMBER: 37637 SUBJECT: GRB 240928A: SVOM/GRM observation DATE: 24/09/30 14:21:02 GMT FROM: Chenwei Wang at IHEP <cwwang(a)ihep.ac.cn> SVOM/GRM team: Chao Zheng, Chen-Wei Wang, Yong-Wei Dong, Jiang-Tao Liu, Shi-Jie Zheng, Jian-Chao Sun, Yue Huang, Jiang He, Min Gao, Hao-Xuan Guo, Lu Li, Yong-Ye Li, Hong-Wei Liu, Xin Liu, Hao-Li Shi, Li-Ming Song, You-Li Tuo, Wen-Jun Tan, Wen-Long Zhang, Hao-Xi Wang, Jin Wang, Jin-Zhou Wang, Ping Wang, Rui-Jie Wang, Yu-Xi Wang, Bo-Bing Wu, Shao-Lin Xiong, Jian-Ying Ye, Yi-Tao Yin, Wen-Hui Yu, Fan Zhang, Li Zhang, Peng Zhang, Shuang-Nan Zhang, Yan-Ting Zhang, Yan-Qiu Zhang, Shu-Min Zhao, Xiao-Yun Zhao (IHEP), Maria-Grazia Bernardini (LUPM/INAF-OAB), Laurent Bouchet (IRAP), David Corre (CEA), Tais Maiolino (LUPM), Frédéric Piron (LUPM), Stéphane Schanne (CEA), Jingwei Wang (IAP) SVOM JSWG: Jian-Yan Wei (NAOC), Bertrand Cordier (CEA), Shuang-Nan Zhang (IHEP), Stéphane Basa (LAM), Shao-Lin Xiong (IHEP), Jean-Luc Attéia (IRAP), Arnaud Claret (CEA), Zi-Gao Dai (USTC), Frédéric Daigne (IAP), Jin-Song Deng (NAOC), Andrea Goldwurm (APC), Diego Götz (CEA), Xu-Hui Han (NAOC), Cyril Lachaud (APC), En-Wei Liang (GXU), Yu-Lei Qiu (NAOC), Susanna Vergani (Obs.Paris), Jing Wang (NAOC), Chao Wu (NAOC), Li-Ping Xin (NAOC), Bing Zhang (UNLV) report on behalf of the SVOM team: During the commissioning phase, the SVOM/GRM was triggered in-flight by a long GRB 240928A (SVOM trigger reference: sb24092803) at 2024-09-28T19:02:10 UT (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 8.7 +0.14/-0.12 s. The GRM light curve can be found here: https://www.bursthub.cn//admin/static/svgrb240928A.png The SVOM/GRM on-ground localization of this burst is (J2000): RA: 6.7 deg DEC: 65.6 deg Error: 8.9 deg (1 sigma, statistical only) We caution that the calibration of SVOM/GRM is undergoing and this localization is subject to systematic errors. The localization may be improved in the refined analysis. ECLAIRs was not collecting data at the time of the burst. 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: Chao Zheng (IHEP)(zhengchao97(a)ihep.ac.cn) View this GCN Circular online at https://gcn.nasa.gov/circulars/37637. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 35563] Fermi GRB 240930A: Global MASTER-Net observations report
by GCN Circulars 30 Sep '24

30 Sep '24

TITLE: GCN CIRCULAR NUMBER: 37636 SUBJECT: Fermi GRB 240930A: Global MASTER-Net observations report DATE: 24/09/30 05:00:35 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov(a)xray.sai.msu.ru> V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko, G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gress, N.M. Budnev, O.Ershova (Irkutsk State University, API), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich (Blagoveschensk Educational State University) MASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 240930A ( Fermi GBM team, GCN 37633) errorbox 592 sec after notice time and 604 sec after trigger time at 2024-09-30 04:17:58 UT, with upper limit up to 19.9 mag. The observations began at zenith distance = 66 deg. The sun altitude is -56.1 deg. The galactic latitude b = -19 deg., longitude l = 303 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2619664 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 664 | 2024-09-30 04:17:58 | MASTER-OAFA | (11h 40m 44.68s , -82d 44m 35.9s) | C | 120 | 18.4 | 665 | 2024-09-30 04:17:58 | MASTER-OAFA | (12h 46m 17.12s , -82d 00m 09.9s) | C | 120 | 19.9 | 819 | 2024-09-30 04:20:17 | MASTER-OAFA | (11h 40m 41.23s , -82d 44m 37.7s) | C | 150 | 18.5 | 819 | 2024-09-30 04:20:18 | MASTER-OAFA | (12h 46m 15.24s , -82d 00m 12.8s) | C | 150 | 19.9 | 1004 | 2024-09-30 04:23:07 | MASTER-OAFA | (11h 40m 38.32s , -82d 44m 40.7s) | C | 180 | 18.3 | 1004 | 2024-09-30 04:23:07 | MASTER-OAFA | (12h 46m 13.12s , -82d 00m 16.7s) | C | 180 | 19.6 | 1203 | 2024-09-30 04:26:27 | MASTER-OAFA | (11h 40m 35.13s , -82d 44m 45.0s) | C | 180 | 18.6 | 1204 | 2024-09-30 04:26:27 | MASTER-OAFA | (12h 46m 10.84s , -82d 00m 21.1s) | C | 180 | 19.9 | 1403 | 2024-09-30 04:29:46 | MASTER-OAFA | (11h 40m 32.39s , -82d 44m 49.6s) | C | 180 | 18.5 | 1403 | 2024-09-30 04:29:47 | MASTER-OAFA | (12h 46m 08.46s , -82d 00m 25.2s) | C | 180 | 19.9 | 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/37636. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 35562] Fermi Gamma-ray Burst Monitor trigger 749362078/240930172 (GRB 240930A) is not a GRB
by GCN Circulars 30 Sep '24

30 Sep '24

TITLE: GCN CIRCULAR NUMBER: 37635 SUBJECT: Fermi Gamma-ray Burst Monitor trigger 749362078/240930172 (GRB 240930A) is not a GRB DATE: 24/09/30 04:58:04 GMT FROM: Cori Fletcher at USRA <cfletcher(a)usra.edu> C. Fletcher (USRA) reports on behalf of the Fermi Gamma-ray Burst Monitor Team: "The Fermi Gamma-ray Burst Monitor (GBM) trigger 749362078/240930172 (GRB 240930A; GCN 37631) at 04:07:53.83 UT on 30 September 2024, tentatively classified as a GRB, is in fact not due to a GRB. This trigger is likely due to local particles." View this GCN Circular online at https://gcn.nasa.gov/circulars/37635. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0

[vsnet-grb-info 35561] LIGO/Virgo/KAGRA S240930aa: Identification of a GW compact binary merger candidate
by GCN Circulars 30 Sep '24

30 Sep '24

TITLE: GCN CIRCULAR NUMBER: 37634 SUBJECT: LIGO/Virgo/KAGRA S240930aa: Identification of a GW compact binary merger candidate DATE: 24/09/30 04:50:24 GMT FROM: Shreejit Jadhav at Swinburne University of Technology <shreejit.jadhav(a)ligo.org> The LIGO Scientific Collaboration, the Virgo Collaboration, and the KAGRA Collaboration report: We identified the compact binary merger candidate S240930aa during real-time processing of data from LIGO Hanford Observatory (H1), LIGO Livingston Observatory (L1), and Virgo Observatory (V1) at 2024-09-30 03:59:59.963 UTC (GPS time: 1411704017.963). The candidate was found by the cWB [1], cWB BBH [2], GstLAL [3], MBTA [4], and SPIIR [5] analysis pipelines. S240930aa is an event of interest because its false alarm rate, as estimated by the online analysis, is 3.1e-19 Hz, or about one in 1e11 years. The event's properties can be found at this URL: https://gracedb.ligo.org/superevents/S240930aa The classification of the GW signal, in order of descending probability, is BBH (>99%), Terrestrial (<1%), NSBH (<1%), or BNS (<1%). Noise transients (glitches) belonging to a known class of instrumental artifacts were present in LIGO Livingston detector data within 10 seconds of the event time, which may affect the parameters or the significance of the candidate. Assuming the candidate is astrophysical in origin, the probability that the lighter compact object is consistent with a neutron star mass (HasNS) is <1%. [6] Using the masses and spins inferred from the signal, the probability of matter outside the final compact object (HasRemnant) is <1%. [6] 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 <1%. 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 [7], distributed via GCN notice about 24 seconds after the candidate event time. * bayestar.multiorder.fits,1, an initial localization generated by BAYESTAR [7], distributed via GCN notice 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 457 deg2. Marginalized over the whole sky, the a posteriori luminosity distance estimate is 1400 +/- 323 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] Klimenko et al. PRD 93, 042004 (2016) doi:10.1103/PhysRevD.93.042004 [2] T. Mishra et al. PRD 105, 083018 (2022) doi:10.1103/PhysRevD.105.083018 [3] Tsukada et al. PRD 108, 043004 (2023) doi:10.1103/PhysRevD.108.043004 and Ewing et al. (2023) arXiv:2305.05625 [4] Aubin et al. CQG 38, 095004 (2021) doi:10.1088/1361-6382/abe913 [5] Chu et al. PRD 105, 024023 (2022) doi:10.1103/PhysRevD.105.024023 [6] Chatterjee et al. ApJ 896, 54 (2020) doi:10.3847/1538-4357/ab8dbe [7] Singer & Price PRD 93, 024013 (2016) doi:10.1103/PhysRevD.93.024013 View this GCN Circular online at https://gcn.nasa.gov/circulars/37634. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0L…

1 0