TITLE: GCN CIRCULAR NUMBER: 35435 SUBJECT: Swift GRB231230.06: Global MASTER-Net observations report DATE: 23/12/30 01:39:58 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@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-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB231230.06 (trigger No 1205319,16h 20m 47.28s , +58d 07m 12.0s, R=0.05) errorbox 12 sec after notice time and 68 sec after trigger time at 2023-12-30 01:30:17 UT, with upper limit up to 18.5 mag. The observations began at zenith distance = 54 deg. The sun altitude is -39.8 deg. MASTER-Kislovodsk robotic telescope located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) was pointed to the Swift GRB231230.06 errorbox 16 sec after notice time and 72 sec after trigger time at 2023-12-30 01:30:20 UT, with upper limit up to 17.2 mag. The observations began at zenith distance = 51 deg. The sun altitude is -34.0 deg. The galactic latitude b = 42 deg., longitude l = 88 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2346177 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 73 | MASTER-Tavrida | C | 10 | 16.1 | 77 | MASTER-Kislovodsk | P- | 10 | 16.0 | 97 | MASTER-Kislovodsk | P- | 50 | 16.7 | Coadd 77 | MASTER-Kislovodsk | P| | 10 | 15.8 | 96 | MASTER-Tavrida | C | 20 | 17.7 | 100 | MASTER-Kislovodsk | P- | 20 | 16.3 | 100 | MASTER-Kislovodsk | P| | 20 | 16.0 | 122 | MASTER-Tavrida | C | 20 | 17.7 | 128 | MASTER-Kislovodsk | P- | 20 | 16.2 | 128 | MASTER-Kislovodsk | P| | 20 | 16.0 | 155 | MASTER-Tavrida | C | 30 | 17.7 | 161 | MASTER-Kislovodsk | P- | 30 | 16.6 | 206 | MASTER-Kislovodsk | P- | 120 | 17.3 | Coadd 161 | MASTER-Kislovodsk | P| | 30 | 16.5 | 196 | MASTER-Tavrida | C | 40 | 17.9 | 206 | MASTER-Kislovodsk | P- | 40 | 16.5 | 206 | MASTER-Kislovodsk | P| | 40 | 16.6 | 242 | MASTER-Tavrida | C | 40 | 17.9 | 259 | MASTER-Kislovodsk | P- | 50 | 16.6 | 259 | MASTER-Kislovodsk | P| | 50 | 16.5 | 294 | MASTER-Tavrida | C | 50 | 17.8 | 322 | MASTER-Kislovodsk | P- | 60 | 16.8 | 322 | MASTER-Kislovodsk | P| | 60 | 16.6 | 361 | MASTER-Tavrida | C | 70 | 18.3 | 444 | MASTER-Tavrida | C | 80 | 18.5 | 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/35435. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...