//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33390 SUBJECT: GRB 230301B: Fermi GBM Final Real-time Localization DATE: 23/03/01 16:39:13 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM The Fermi GBM team reports the detection of a likely SHORT GRB At 16:28:43 UT on 1 Mar 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230301B (trigger 699380928.235244 / 230301687). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 66.6, Dec = -7.0 (J2000 degrees, equivalent to J2000 04h 26m, -7d 00'), with a statistical uncertainty of 9.6 degrees. The angle from the Fermi LAT boresight is 31.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230301687/quicklook/glg_skymap_all_bn230301687.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/bn230301687/quicklook/glg_healpix_all_bn230301687.fit The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230301687/quicklook/glg_lc_medres34_bn230301687.gif //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 33391 SUBJECT: Fermi GRB 230301B: Global MASTER-Net observations report DATE: 23/03/01 18:45:27 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-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 230301B ( Fermi GBM team, GCN 33390) errorbox 5485 sec after notice time and 5518 sec after trigger time at 2023-03-01 18:00:41 UT, with upper limit up to 16.5 mag. Observations started at twilight. The observations began at zenith distance = 33 deg. The sun altitude is -10.4 deg. The galactic latitude b = -35 deg., longitude l = 202 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2201848 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 5548 | 2023-03-01 18:00:41 | MASTER-SAAO | (04h 17m 12.02s , -08d 22m 17.7s) | C | 60 | 16.0 | 5548 | 2023-03-01 18:00:41 | MASTER-SAAO | (04h 14m 06.70s , -08d 22m 37.9s) | C | 60 | 16.2 | 5628 | 2023-03-01 18:02:01 | MASTER-SAAO | (04h 25m 11.32s , -08d 23m 13.2s) | C | 60 | 15.1 | 5628 | 2023-03-01 18:02:01 | MASTER-SAAO | (04h 24m 20.52s , -08d 23m 32.5s) | C | 60 | 15.5 | 5708 | 2023-03-01 18:03:20 | MASTER-SAAO | (04h 16m 02.76s , -06d 27m 35.7s) | C | 60 | 15.0 | 5708 | 2023-03-01 18:03:20 | MASTER-SAAO | (04h 15m 12.37s , -06d 27m 54.7s) | C | 60 | 15.2 | 5798 | 2023-03-01 18:04:51 | MASTER-SAAO | (04h 24m 06.21s , -06d 29m 00.3s) | C | 60 | 14.8 | 5798 | 2023-03-01 18:04:51 | MASTER-SAAO | (04h 23m 15.75s , -06d 29m 19.5s) | C | 60 | 15.0 | 5889 | 2023-03-01 18:06:22 | MASTER-SAAO | (04h 31m 18.06s , -06d 28m 01.1s) | C | 60 | 15.0 | 5889 | 2023-03-01 18:06:22 | MASTER-SAAO | (04h 30m 27.52s , -06d 28m 19.7s) | C | 60 | 15.1 | 5969 | 2023-03-01 18:07:41 | MASTER-SAAO | (04h 39m 22.10s , -06d 26m 58.0s) | C | 60 | 15.7 | 5969 | 2023-03-01 18:07:41 | MASTER-SAAO | (04h 38m 31.49s , -06d 27m 16.7s) | C | 60 | 15.9 | 6059 | 2023-03-01 18:09:12 | MASTER-SAAO | (04h 32m 29.23s , -08d 22m 55.6s) | C | 60 | 16.0 | 6059 | 2023-03-01 18:09:12 | MASTER-SAAO | (04h 31m 38.37s , -08d 23m 14.6s) | C | 60 | 16.1 | 6139 | 2023-03-01 18:10:32 | MASTER-SAAO | (04h 40m 39.33s , -08d 22m 40.1s) | C | 60 | 16.1 | 6139 | 2023-03-01 18:10:32 | MASTER-SAAO | (04h 39m 48.37s , -08d 22m 59.2s) | C | 60 | 16.4 | 6230 | 2023-03-01 18:12:02 | MASTER-SAAO | (04h 30m 28.83s , -04d 34m 44.1s) | C | 60 | 15.3 | 6230 | 2023-03-01 18:12:02 | MASTER-SAAO | (04h 29m 38.50s , -04d 35m 02.9s) | C | 60 | 15.6 | 6309 | 2023-03-01 18:13:22 | MASTER-SAAO | (04h 38m 33.36s , -04d 32m 52.0s) | C | 60 | 15.4 | 6309 | 2023-03-01 18:13:22 | MASTER-SAAO | (04h 37m 42.95s , -04d 33m 10.8s) | C | 60 | 15.4 | 6401 | 2023-03-01 18:14:53 | MASTER-SAAO | (04h 33m 57.41s , -10d 14m 45.2s) | C | 60 | 16.2 | 6401 | 2023-03-01 18:14:53 | MASTER-SAAO | (04h 33m 06.17s , -10d 15m 04.4s) | C | 60 | 16.3 | 6492 | 2023-03-01 18:16:25 | MASTER-SAAO | (04h 42m 10.78s , -10d 15m 42.3s) | C | 60 | 16.3 | 6492 | 2023-03-01 18:16:25 | MASTER-SAAO | (04h 41m 19.46s , -10d 16m 01.2s) | C | 60 | 16.5 | 6572 | 2023-03-01 18:17:45 | MASTER-SAAO | (04h 16m 13.41s , -08d 22m 57.4s) | C | 60 | 15.9 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.