The International Workshop on
Quark Phase Transition in Compact Objects and Multimessenger Astronomy:
Neutrino Signals, Supernovae and Gamma-Ray Bursts

7-14 October 2015

Energy Injections in Gamma Ray Bursts Yu Y. B., Wu X. F., Huang Y. F., Xu M.

Abstract

      In this study, we will introduce some special events, such as GRBs 081029, 100814A and 111209A. Unexpected features, such as multiple X-ray flares and significant optical rebrightenings, are observed in their afterglow light curves, unveiling the late-time activities of the central engines. Here, we will summarize our previous numerical results of these three bursts by using the energy injection model. Especially, we will focus on GRB 100814A, with an early-time shallow decay phase and a late-time significant rebrightening in its optical afterglow light curve. To explain the complex multi-band afterglow emission of GRB 100814A, we invoke a magnetar with spin evolution as its central engine. We argue that the optical shallow decay phase and the X-ray plateau are due to energy injection from the magnetar in its early spin-down stage, while the significant optical rebrightening observed at late time naturally comes from the spin-up process of the magnetar, which is caused by subsequent fall back accretion.

Reference:
Yu Y. B., Wu X. F., Huang Y. F., Xu M., "Energy Injections in Gamma Ray Bursts", in "Proceedings of the International Workshop on Quark Phase Transition in Compact Objects and Multimessenger Astronomy: Neutrino Signals, Supernovae and Gamma-Ray Bursts", Russia, Nizhnij Arkhyz (SAO RAS), Terskol (BNO INR RAS), October, 7 - 14, 2015, Publishing house "Sneg", Pyatigorsk, 2016, ISBN 978-5-903129-85-0, pp. 168-174.
DOI: 10.26119/SAO.2020.1.51295
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