AI 中文总结
本研究提出一种方法，通过拟合修正后的子暴斜率定律，从重复快速射电暴光谱中解耦散射、色散等传播效应，实现对FRB源物理特性的更可靠推断。
AI 中文摘要
我们提出一种方法，用于将重复快速射电暴（Fast Radio Burst, FRB）的传播效应（具体为散射和色散）与其本征谱时特性解耦。利用触发相对论动力学模型（Triggered Relativistic Dynamical Model），并假设超辐射为辐射机制，我们生成模拟子暴并注入可控水平的散射和剩余色散。对每个暴，我们测量子暴斜率（定义为动态谱中质心的轨迹）和暴轮廓的特征持续时间。随后，我们对所得的斜率-持续时间测量值拟合修正后的子暴斜率定律，以恢复散射时标、剩余色散量及其他模型参数。在薄屏近似下，1 GHz处的散射时标可被精确恢复，通常误差在真实值的~1-2%以内；相比之下，剩余色散的恢复精度较低，中位绝对误差为~0.3-0.6 pc cm⁻³，这反映了其约束较弱且与本征参数存在简并。尽管如此，修正后的子暴斜率定律仍能成功复现谱时演化，即使针对不同本征暴群体也能精确约束散射特性。这些结果表明，我们的框架提供了一种可处理的方法，能在一定程度上将传播诱导的畸变与本征辐射特性分离，从而实现对FRB源物理特性更可靠的推断。
英文摘要
We present a methodology to decouple propagation effects, specifically scattering and dispersion, from the intrinsic spectro-temporal properties of repeating Fast Radio Bursts. Utilizing the Triggered Relativistic Dynamical Model, and assuming superradiance as the emission mechanism, we generate simulated sub-bursts and inject controlled levels of scattering and residual dispersion. For each burst, we measure the sub-burst slope, defined as the trajectory of the centroids in the dynamic spectrum, and the characteristic duration of the burst profile. We then fit a modified sub-burst slope law to the resulting slope-duration measurements to recover the scattering timescale, residual dispersion measure, and other model parameters. Under the thin-screen approximation, the scattering timescale at $1~\mathrm{GHz}$ is precisely recovered, typically to within $\sim 1-2\%$ of the true value. In contrast, the residual dispersion is recovered with comparatively lower precision, with median absolute errors of $\sim 0.3-0.6\ \mathrm{pc \, cm^{-3}}$, reflecting its weaker constraint and degeneracy with an intrinsic parameter. Despite this, the modified sub-burst slope law successfully reproduces the spectro-temporal evolution and accurately constrains the scattering properties even for diverse intrinsic burst populations. These results demonstrate that our framework yields a tractable method for separating propagation-induced distortions from intrinsic emission characteristics to a meaningful degree, enabling more reliable inference of the physical properties of FRB sources.
Comments16 pages, 7 figures, to be submitted to New Astronomy
