| Abstract : | Gamma-ray bursts (GRBs) are the brightest explosions in the universe. Despite several decades of observations, the nature of GRBs still remains elusive. This work uses an extensive Neil Gehrels Swift observatory database to conduct a systematic correlation study between the GRB prompt emission and X-Ray flares in the afterglow. The study of flares superimposed on the afterglow of GRBs will help us to enhance our understanding of the nature of the environment and the process of the central engine that gives rise to delayed flaring.
We have used 15 years (2005-2020) of Swift observations. 240 GRBs with X-Ray flares were identified. Different temporal parameters like duration, quiescent period (the period of inactivity of the central engine after prompt emission) and minimum timescale variability are measured using observed count light curves. In addition, spectral properties like energy flux, energy fluence and the spectral photon index of both the prompt emission and the individual flare episodes were measured.
These parameters' distributions and the correlations between prompt and flare emissions are presented. A positive correlation is observed between the quiescent period and the flare duration. The consecutive flaring episodes are longer and less energetic than the preceding flare episodes, as well as the prompt emission. Also, the minimum variability timescale of the X-Ray flare light curves tends to be larger than that of the prompt emission. A catalogue of these parameters characterising the prompt and flare emissions is produced. The implications of the observed correlations are discussed with respect to the model [Beniamini & Kumar 2016], suggesting that the central engine is the origin of observed late-time flares. Combining theoretical model and observational evidence, an understanding of the reason behind observed characteristics are made.
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