Self-organized Criticality across Precursor, Main, and Extended Emission Phases of Gamma-Ray Bursts
伽马射线暴前兆、主发射与延展发射阶段的自组织临界性
We investigate the self-organized criticality (SOC) signatures of the precursor, main emission, extended emission (EE), and whole emission phases for three-phase gamma-ray bursts (GRBs). These parameters include the conventional duration-based index T<SUB>100</SUB>, as well as the newly introduced parameters T<SUB>MVT</SUB> and spectral lags (τ<SUB>32</SUB>, τ<SUB>42</SUB>). All cumulative distributions show power-law scaling in each phase for both Type I and Type II GRBs. For the first time, we demonstrate that the EE phase exhibits the same SOC scaling as the other phases. Phase-to-phase ratios show that spectral lag ratios are correlated, while duration-based ratios are not, indicating a common origin for spectral lags. Statistical comparisons among the four indexes reveal no significant differences across phases or within each phase, except in the EE phase where T<SUB>MVT</SUB> is marginally different from the spectral lags. When compared with the three-dimensional expectation α = 2.0 (duration-based), T<SUB>MVT</SUB> and T<SUB>100</SUB> show no significant deviation, whereas spectral lags seem to follow the fluence scaling α ≍ 1.5 as predicted by the fractal-diffusive SOC model. Thus, the same magnetic reconnection driven avalanche likely operates throughout the entire GRB, and these new parameters provide new observational diagnostics of the avalanche process.
展开 ▾首次证明延展发射（EE）阶段具有与其他阶段相同的 SOC 标度；新引入 T_MVT 与谱延迟参数为雪崩过程提供新的观测诊断。
以往对 GRB 自组织临界性的研究多集中在主发射或延展发射的持续时间分布，较少系统比较前兆、主发射、延展发射和全程的统一标度行为。该文将传统 T100 与新提出的 T_MVT 及谱延迟等参数纳入同一框架，在 Type I/II GRB 各时相中均得到幂律累积分布，首次把 SOC 证据延伸到延展发射阶段。谱延迟比的相关性以及谱延迟更接近 fluence 标度 α≈1.5，提示其与持续时标参数可能追踪雪崩过程的不同侧面。从趋势看，未来可把这类多参数、多时相 SOC 诊断拓展到更大样本和更高时间分辨率，以检验磁重联雪崩图像在 GRB 全过程中的普适性。
接收 2026-07-08 · 刊出 2026-07-30 · 收录 2026-08-20