//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33490 SUBJECT: GRB 230321A: Fermi GBM Final Real-time Localization DATE: 23/03/21 04:32:02 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM The Fermi GBM team reports the detection of a likely LONG GRB At 04:21:43 UT on 21 Mar 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230321A (trigger 701065308.721614 / 230321182). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 74.8, Dec = 28.0 (J2000 degrees, equivalent to J2000 04h 59m, 28d 00'), with a statistical uncertainty of 6.2 degrees. The angle from the Fermi LAT boresight is 53.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230321182/quicklook/glg_skymap_all_bn230321182.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/bn230321182/quicklook/glg_healpix_all_bn230321182.fit The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230321182/quicklook/glg_lc_medres34_bn230321182.gif //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33491 SUBJECT: GRB 230321A: BALROG localization (Fermi Trigger 701065308 / GRB 230321182) DATE: 23/03/21 04:42:41 GMT FROM: Jochen Greiner at MPE,Garching F. Kunzweiler, B. Biltzinger, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report: The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger 701065308 at 04:21:43 on 21 Mar. 2023 were automatically fitted for spectrum and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427; Berlato et al. 2019, ApJ 873, 60). The best-fit position (1 sigma statistical errors) is: RA(2000.0) = 65.24+/-1.54 deg Decl.(2000.0) = 31.70+/-1.26 deg We estimate an additional systematic error of 2 deg. Further details are available at: https://grb.mpe.mpg.de/grb/GRB230321182/ The Healpix map can be downloaded from: https://grb.mpe.mpg.de/grb/GRB230321182/healpix The location parameters are available as JSON at: https://grb.mpe.mpg.de/grb/GRB230321182/json //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33497 SUBJECT: Fermi GRB 230321A: Global MASTER-Net observations report DATE: 23/03/21 14:15:09 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-Amur robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Blagoveshchensk State Pedagogical University) started inspect of the Fermi GRB 230321A ( Fermi GBM team, GCN 33490) errorbox 31100 sec after notice time and 31106 sec after trigger time at 2023-03-21 13:00:10 UT, with upper limit up to 17.0 mag. The observations began at zenith distance = 54 deg. The sun altitude is -29.6 deg. The galactic latitude b = -8 deg., longitude l = 175 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2205320 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 31137 | 2023-03-21 13:00:10 | MASTER-Amur | (05h 01m 25.52s , +27d 54m 19.8s) | C | 60 | 17.0 | 31219 | 2023-03-21 13:01:32 | MASTER-Amur | (05h 10m 28.51s , +27d 52m 42.3s) | C | 60 | 16.9 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33502 SUBJECT: GRB 230321A: CALET Gamma-Ray Burst Monitor detection DATE: 23/03/22 04:07:36 GMT FROM: Yuta Kawakubo at Louisiana State U./CALET N. Cannady (GSFC/UMBC), 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), M. L. Cherry (LSU), S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena), and the CALET collaboration: The long GRB 230321A (Fermi GBM Final Real-time Localization: Fermi GBM team, GCN Circ. 33490; BALROG localization: Kunzweiler et al., GCN Circ 33491) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 04:21:42.09 UTC on 21 March 2023 (http://cgbm.calet.jp/cgbm_trigger/flight/1363407527/index.html). The burst signal was seen by all CGBM detectors. The burst light curve shows a multi-peaked structure that starts at T+1.0 sec, peaks at T+31.9 sec, and ends at T+86.6 sec. The T90 and T50 durations measured by the SGM data are 75.5 +/- 1.2 sec and 35.4 +/- 3.1 sec (40-1000 keV), respectively. The ground-processed light curve is available at http://cgbm.calet.jp/cgbm_trigger/ground/1363407527/ The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at Waseda University.