Evidence for a Similar Physical Origin Between Prompt Emission and X-Ray Flares of Gamma-Ray Bursts

@misc{yu2026evidence,
  title = {{Evidence for a Similar Physical Origin Between Prompt Emission and X-Ray Flares of Gamma-Ray Bursts}},
  author = {Wen-Yuan Yu and Wen-Long Zhang and Hou-Jun Lü},
  howpublished = {arXiv},
  year = {2026},
  month = oct,
  doi = {10.48550/arxiv.2610.09538},
  eprint = {2610.09538},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2610.09538},
  note = {CC0},
}

TY  - UNPB
TI  - Evidence for a Similar Physical Origin Between Prompt Emission and X-Ray Flares of Gamma-Ray Bursts
AU  - Wen-Yuan Yu
AU  - Wen-Long Zhang
AU  - Hou-Jun Lü
PY  - 2026
DA  - 2026/10/07
PB  - arXiv
DO  - 10.48550/arxiv.2610.09538
UR  - https://arxiv.org/abs/2610.09538
AB  - Statistical properties of X-ray flares are highly similar to those of the prompt emission in gamma-ray bursts (GRBs), suggesting that they may share a common physical origin (e.g., central engine activity). However, comparable statistical studies of afterglow X-ray flares and prompt gamma-ray pulses that are not observed simultaneously remain incomplete. In this paper, by systematically searching for gamma-ray emission simultaneous with X-ray flares, we identify 38 GRBs containing 50 pulse--flare pairs, 19 of which have measured redshifts. We perform joint temporal and spectral analyses of the gamma-ray pulses and X-ray flares over their overlapping time intervals, and find that the spectrum of each pair can be well described by an absorbed power-law (PL), PL plus blackbody (PL+BB), cutoff power-law (CPL), and Band function. More importantly, by applying self-organized criticality (SOC) analysis to both the prompt gamma-ray pulses and the simultaneously observed X-ray flares, we find that the temporal parameters (e.g., waiting time, rise time, peak time, decay time, and duration) of the two components follow similar power-law distributions, with the largest absolute difference of Δα∼0.36 for the waiting time and much smaller differences (Δα≲0.12) for the other four parameters. For the isotropic energy derived from the subsample with measured redshifts, the difference between the two components is Δα∼0.54. These results suggest that the X-ray flares and the prompt emission are likely to share the same physical origin.
ER  -