TITLE: GCN CIRCULAR NUMBER: 36603 SUBJECT: GRB 240529A: MASTER prompt OT detection DATE: 24/06/03 05:40:18 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru> V.Lipunov (MSU), D.Buckley (SAAO), K.Zhirkov, G.Antipov, E.Gorbovskoy, A.Kuznetsov, D.Vlasenko, P.Balanutsa, N.Tiurina, Ya.Kechin, Yu.Tselik, D.Zimnukhov, V.Senik, A.Yudin, V.Topolev, A.Chasovnikov,D.Cheryasov(Lomonosov MSU,SAI,PhysicsDepartment), O.Gress, N.Budnev(ISU), A.Sosnovskij (Crimean Astrophysical Observatory, RAS), C.Francile. F. Podesta, R.Podesta (Observatorio Astronomico Felix AguilarOAFA), R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity) MASTER Global robotic net (http://observ.pereplet.ru Lipunov etal.,2010,Advances in Astronomy,2010,30L) started observation (Lipunov et al. GCN 36555) of Swift GRB240529A (Eyles-Ferris et al. GCN36556, Ttrigger= 02:58:31UT) in MASTER-SAAO at 3 degrees altitude at 2024-05-29 02:59:20 by wide-field MASTER-II camera and at 2024-05-29 02:59:16 (44s after GRB time) by very wide field MASTER-VWF camera. The optical transient MASTER OT J222126.06+513344.6 clearly detected since 03:00:20 with m_OT~14.5 at first maximum and with possible second maximum at light curve during prompt emission of this GRB (Swift-BAT lightcurve Markwardt,Barthelmy et al. GCN36566) The reduction of first 40 images from MASTER-VWFC since 2024-05-29 02:59:16 with OT substraction will be continued. Observations started at zenith distance = 87 deg. The sun altitude was -31.0deg. The galactic latitude b = -5 deg., longitude l = 101 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2474976 View this GCN Circular online at https://gcn.nasa.gov/circulars/36603. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...