Three-stage Collapse of the Long Gamma-Ray Burst from GRB 160625B Prompt Multiwavelength Observations

Lipunov, VM;Sadovnichy, VA;Panasyuk, MI;Yashin, IV;Svertilov, SI;Simakov, SG;Svinkin, D;Gorbovskoy, E;Lipunova, GV;Kornilov, VG;Frederiks, D;Topolev, V;Rebolo, R;Serra, M;Tiurina, N;Minkina, E;Bogomolov, VV;Bogomolov, AV;Iyudin, AF;Chasovnikov, A;Gabovich, A;Tsvetkova, A;Budnev, NM;Gress, OA;Antipov, G;Gorbunov, I;Vlasenko, D;Balanutsa, P;Podesta, R;Zhirkov, K;Kuznetsov, A;Vladimirov, V;Podesta, F;Francile, C;Sergienko, Y;Tlatov, A;Ershova, O;Cheryasov, D;Yurkov, V;Krylov, AV

2023-01-01

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Abstract

This article presents the early results of synchronous multiwavelength observations of one of the brightest gamma-ray bursts (GRBs) GRB 160625B with the detailed continuous fast optical photometry of its optical counterpart obtained by MASTER and with hard X-ray and gamma-ray emission, obtained by the Lomonosov and Konus-Wind spacecraft. The detailed photometry led us to detect the quasi-periodical emission components in the intrinsic optical emission. As a result of our analysis of synchronous multiwavelength observations, we propose a three-stage collapse scenario for this long and bright GRB. We suggest that quasiperiodic fluctuations may be associated with forced precession of a self-gravitating rapidly rotating superdense body (spinar), whose evolution is determined by a powerful magnetic field. The spinar's mass allows it to collapse into a black hole at the end of evolution.