Study on Spectral Lag and Flare Characters Based on GRB 051117A

Researches show thatthere is a strong correlation between the spectral lag of flare and flare characteristic parameters (peak time, width, rise time, decay time), as time goes on, the flare becomes wider and the spectral lag becomes larger. We use the discrete-correlation function (DCF) to study the spectral lag of a multi-flare GRB (GRB 051117A)with 10 flares, it is found that within GRB 051117A, the spectral lag is also strongly correlated with the peak time, width, rise time and decay time of the flares. this is, lag∝t_peak, ω, t_rise, t_decay. The flares will also evolve over time within a GRB. This work extends the relationship between the spectral lag between GRBs and the characteristic parameters of flares to the interior of GRBs, which can help us have a deeper understanding of multi-flare GRBs. Moreover, the correlation between the flare characteristic parameters within GRB 051117A is highly similar to that between multiple GRBs and even prompt emission pulses. This also supports that X-ray flares and prompt emission pulses may have the same physical origin.