Abstract Details

Name: Manoneeta Chakraborty
Affiliation: IIT Indore
Conference ID: ASI2021_494
Title : Investigations of magnetar flares and their implications
Authors and Co-Authors : J. Yang, V. Chand, B. Zhang, Y. Yang, J. Zou, Y. Yang, X. Zhao, L. Shao, S. Xiong, Q. Luo, X. Li, S. Xiao, C. Li, C. Liu, J. Joshi, V. Sharma, M. Chakraborty, B. Zhang, E. Gogus, S. Sasmaz Mus, Y. Kaneko, Berk Aydin, L. Lin, C. Kouveliotou, A. Watts, M. A. Alpar, D. Huppenkothen, O. J. Roberts, G. Younes, A. J. van der Horst, A. Chakraborty
Abstract Type : Invited
Abstract Category : Stars, ISM and Galaxy
Abstract : Neutron stars offer the most extreme magnetic field in the universe, which is crucial in governing such objects' radiative behaviour and temporal evolution. Such dense objects display a wide plethora of observational features carrying the direct signatures of the complex extreme magnetic field and the strong gravity field. Extremely energetic flares lasting from few fractions of a second to 100s of seconds are observed from magnetars- the strongest magnetic neutron stars. Such bursts are proposed to originate from sudden fracturing of the neutron star crust due to building up magnetic stress or from magnetic reconnection in a highly magnetized environment. The burst properties vary widely from repetitive short bursts to super-Eddington giant flares. During these episodes, the spectral and temporal properties were found to be distinctly different from the magnetar persistent emission. Understanding the observational features during such transient events can probe the flaring mechanism and the corresponding energetics. We investigate the energetics and spectral properties of the flares to identify the trigger mechanism, examine the emission and radiative physics at the flare origin site, and infer about the complex magnetic field morphology from the concurrently occurring spectral lines. Finally, our results show that the most energetic magnetar flares offer the most natural explanation for the observed properties like - temporal and spectral features, energy, statistical correlations - of a short gamma-ray burst (sGRB). This indicated a giant flare origin for at least a fraction of the observed sGRBs establishing a strong connection between them.