//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33553 SUBJECT: GRB 230402A: Fermi GBM Final Real-time Localization DATE: 23/04/02 07:42:54 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM The Fermi GBM team reports the detection of a likely LONG GRB At 07:32:35 UT on 2 Apr 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230402A (trigger 702113560.95607 / 230402314). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 93.1, Dec = -14.6 (J2000 degrees, equivalent to J2000 06h 12m, -14d 35'), with a statistical uncertainty of 1.0 degrees. The angle from the Fermi LAT boresight is 18.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230402314/quicklook/glg_skymap_all_bn230402314.png The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230402314/quicklook/glg_healpix_all_bn230402314.fit The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230402314/quicklook/glg_lc_medres34_bn230402314.gif //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33554 SUBJECT: Fermi GRB 230402A: Global MASTER-Net observations report DATE: 23/04/02 16:45:20 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko, G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin (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. Gres, N.M. Budnev (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), A. Gabovich, V.Yurkov (Blagoveschensk Educational State University) MASTER-Kislovodsk robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the Fermi GRB 230402A ( Fermi GBM team, GCN 33553) errorbox 32029 sec after notice time and 32063 sec after trigger time at 2023-04-02 16:26:59 UT, with upper limit up to 15.8 mag. Observations started at twilight. The observations began at zenith distance = 61 deg. The sun altitude is -9.7 deg. The galactic latitude b = -15 deg., longitude l = 222 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2208192 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 32093 | 2023-04-02 16:26:59 | MASTER-Kislovodsk | (06h 16m 40.71s , -13d 55m 08.5s) | C | 60 | 15.1 | 32093 | 2023-04-02 16:26:59 | MASTER-Kislovodsk | (06h 12m 36.97s , -13d 34m 24.3s) | C | 60 | 14.9 | 32173 | 2023-04-02 16:28:19 | MASTER-Kislovodsk | (06h 20m 08.03s , -15d 50m 10.7s) | C | 60 | 15.3 | 32173 | 2023-04-02 16:28:19 | MASTER-Kislovodsk | (06h 16m 01.99s , -15d 29m 26.3s) | C | 60 | 15.1 | 32254 | 2023-04-02 16:29:39 | MASTER-Kislovodsk | (06h 04m 14.25s , -15d 51m 29.2s) | C | 60 | 15.1 | 32334 | 2023-04-02 16:30:59 | MASTER-Kislovodsk | (06h 13m 51.45s , -12d 03m 02.3s) | C | 60 | 15.4 | 32334 | 2023-04-02 16:30:59 | MASTER-Kislovodsk | (06h 09m 48.34s , -11d 42m 21.4s) | C | 60 | 15.3 | 32414 | 2023-04-02 16:32:19 | MASTER-Kislovodsk | (06h 01m 04.95s , -13d 55m 45.9s) | C | 60 | 15.4 | 32815 | 2023-04-02 16:39:00 | MASTER-Kislovodsk | (06h 16m 46.40s , -13d 56m 31.5s) | C | 60 | 15.8 | 32815 | 2023-04-02 16:39:01 | MASTER-Kislovodsk | (06h 12m 42.92s , -13d 35m 50.8s) | C | 60 | 15.7 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33555 SUBJECT: GRB 230402A: AGILE detection DATE: 23/04/02 19:27:16 GMT FROM: Claudio Casentini at INAF-IAPS C. Casentini (INAF/IAPS), C. Pittori (SSDC, and INAF/OAR), M. Tavani (INAF/IAPS and Uni. Roma Tor Vergata), F. Lucarelli, F. Verrecchia(SSDC, and INAF/OAR), A. Argan, M. Cardillo, Y. Evangelista, L. Foffano, G. Piano (INAF/IAPS), A. Addis, L. Baroncelli, A. Bulgarelli, A. Di Piano, V. Fioretti, G.Panebianco, N. Parmiggiani (INAF/OAS-Bologna), M. Romani (INAF/OA-Brera), M. Marisaldi (INAF/OAS-Bologna, Bergen University), M. Pilia, A. Trois (INAF/OA Cagliari), I. Donnarumma, E. Menegoni, A.Ursi (ASI), A. Giuliani (INAF/IASF-Mi) and P. Tempesta (TeleSpazio), report on behalf of the AGILE Team: The AGILE satellite detected the GRB 230402A at T0 = 2023-04-02 07:32:35 s (UTC), reported by Fermi GBM (GCN #33553). The burst is clearly visible in the AGILE scientific ratemeters of the MiniCALorimeter (MCAL; 0.4-100 MeV), and AntiCoincidence (AC; 50-200 keV) detectors. The event lasted about 6 s and it released a total number of 5504 counts in the MCAL detector (above a background rate of 576 Hz), and 23987 counts in AC detector (above a background rate of 2949 Hz). The AGILE ratemeters light curves can be found at http://www.agilescienceapp.it/notices/GRB230402A_AGILE_RM_ND.png . At the T0, the event was 81 deg off-axis. Additional analysis of AGILE data is in progress. Automatic MCAL GRB alert Notices can be found at: https://gcn.gsfc.nasa.gov/agile_mcal.html //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33562 SUBJECT: GRB 230402A: AstroSat CZTI detection DATE: 23/04/04 14:11:20 GMT FROM: Gaurav Waratkar at IIT,Bombay P K. Navaneeth (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 ML pipeline (Abraham et al., 2021, MNRAS, 504, 3084) and the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a bright long GRB 230402A which was also detected by Fermi (Fermi GBM Team, GCN 33553), and AGILE (Casentini et al., GCN 33555). The source was clearly detected in the 20-200 keV energy range. The light curve peaks at 2023-04-02 07:32:36.5 UTC. The measured peak count rate associated with the burst is 517 (+50, -55) counts/s above the background in the combined data of all quadrants, with a total of 4283 (+374, -394) counts. The local mean background count rate was 456 (+3, -4) counts/s. Using cumulative rates, we measure a T90 of 37 (+3, -5) s. In the preliminary analysis, we find 588 Compton events associated with this event. The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-04-02 07:32:36.1 UTC. The measured peak count rate associated with the burst is 692 (+67, -76) counts/s above the background in the combined data of three quadrants (out of four), with a total of 5504 (+695, -805) counts. The local mean background count rate was 1185 (+2, -2) counts/s. We measure a T90 of 37 (+21, -9) s from the cumulative Veto light curve. 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 //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33563 SUBJECT: GRB 230402A: CALET Gamma-Ray Burst Monitor detection DATE: 23/04/04 15:29:58 GMT FROM: Yuta Kawakubo at Louisiana State U./CALET M. L. Cherry (LSU), A. Yoshida, T. Sakamoto, S. Sugita (AGU), Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN), Y. Asaoka (ICRR), S. Torii, Y. Akaike, K. Kobayashi (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC), S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena), and the CALET collaboration: The long GRB 230402A (Fermi GBM Final Real-time Localization: Fermi GBM team, GCN Circ. 33553; AGILE detection: Casentini et al., GCN Circ 33555; AstroSat CZTI detection: Navaneeth et al., GCN Circ. 33562) triggered the CALET Gamma-ray Burst Monitor (CGBM)at 07:32:38.72 UTC on 2 April 2023 (http://cgbm.calet.jp/cgbm_trigger/flight/1364455761/). The burst signal was seen by only the SGM detector. The burst light curve shows a single pulse that starts at T-3.2 sec and ends at T+4.8 sec. The T90 and T50 durations measured by the SGM data are 7.0 +/- 1.0 sec and 4.0 +/- 1.0 sec (40-1000 keV), respectively. The ground-processed light curve is available at http://cgbm.calet.jp/cgbm_trigger/ground/1364455761/ The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at Waseda University.