2025/10/21 by Shu-Xu Yi, Yi, Shu-Xu, Chenwei Wang +13
Physics and Astronomy · #Astro and Planetary Science #Astronomy and Astrophysical Research #Curiosity #Energy (signal processing) #FOS: Physical sciences #Gamma-ray burst #Gamma-ray bursts and supernovae #High Energy Astrophysical Phenomena (astro-ph.HE) #Ideal (ethics) #Radiation #Spectral properties #Starlight
paper · pdf · doi:10.48550/arxiv.2510.18207
published in ArXiv.org
openalex publication_date 2025/10/21 · openalex created_date 2025/10/24 · openalex updated_date 2026/08/04
To understand the physical mechanisms underlying the prompt emission of gamma-ray bursts (GRB), single FRED (Fast-Rise-Exponential-Decay) profile GRBs serve as an ideal sample, as they origin from single epoch central engine activity. These GRBs have been found to exhibit a peculiar morphology-including the elegant cross-energy-similarity across energy bands and the recently discovered composite nature-challenging nearly all existing radiation mechanisms, sparking widespread curiosity about their origins. Here we propose a physical model which includes radiation locations sequentially triggered by propagating magnetic perturbations. It naturally explains all observed properties of these GRBs, including the self-similar FRED profile, multi-band aligned subpulses, hard-to-soft spectral evolution, local intensity tracking, and increasing subpulse durations. Furthermore, our results demonstrate that the duration of these GRBs is not reflecting the activity timescale of the central engine, reconciling recent challenges to the traditional merger-short/collapsar-long dichotomy of GRBs.