arXiv subjects

Jia-Peng Wei

Publications and source records attributed to Jia-Peng Wei.

2 recordsLinked to original sources

arXiv2026

Constraining the Supernova Remnant Environment of FRB 190520B with Dispersion Measure and Scattering Timescale

FRB 190520B is a repeating fast radio burst source whose large dispersion measure (DM) and temporal broadening suggest a dense and evolving local environment. In this work, we test the possibility that FRB 190520B originates from the core-collapse of a massive star so that its central engine is embedded in a supernova remnant (SNR) expanding into a wind environment, whose evolution is described by the self-similar solution. We use the observed DM and scattering timescale of FRB 190520B to constrain the physical parameters of its surrounding SNR and host-galaxy DM. Twenty typical cases are considered, arising from four ejecta profiles and five scattering prescriptions. It is found that only 6 cases are retained and provide acceptable fits. All retained cases have a shallow ejecta profile and a young source age of $t_0=79.8$--$169.8~{\rm yr}$. The ejecta mass is inferred to be large for all six cases, while the kinetic energy and mass-loss rate span a wide range. The secular DM evolution is reproduced better than the detailed scattering evolution. The up-drift behavior of the scattering residual suggests an additional component or more complicated structures inside the SNR. All retained cases are self-consistent within the adopted scattering theory and the circum-burst medium becomes transparent for GHz bursts before the inferred source ages.

astro-ph.HE↗

arXiv2025

Intrinsic Pulse Widths of FRB 20121102A and Calculation of Broadening from Propagation and Instrumental Effects

The pulse widths of fast radio bursts are always broadened due to the scattering of the plasma medium through which the electromagnetic wave passes. The recorded pulse width will be further affected by the radio telescopes since the sampling time and the bandwidth cannot be infinitely small. In this study, we focus on the pulse widths of at least 3287 bursts detected from FRB 20121102A as of October 2023. Various effects such as the scattering broadening, the redshift-induced broadening and the instrumental broadening are examined. At a redshift of 0.193, the pulse width is broadened by a factor of approximately 0.16 due to cosmological time dilation. It is found that the instrumental broadening only contributes a fraction of $10^{-3}$ -- $10^{-1}$ to the observed pulse width. The scattering broadening is even smaller, which constitutes a tiny fraction of $10^{-5}$ -- $10^{-2}$ in the observed pulse width. After correcting for these broadenings, the intrinsic pulse width is derived for each burst. The maximum and minimum pulse widths at different frequencies are highlighted. The intrinsic widths of most bursts are in a narrow range of 1 -- 10 ms, which leads to a quasi-linear correlation between the fluence and the peak flux. Besides, the mean value and the dispersion range of intrinsic pulse width are found to scale with the central frequency as $ν^{-1.2 \pm 0.2}$ and $ν^{-1.7 \pm 0.6}$, respectively.

astro-ph.HE↗