2014/07/03 by J. J. Geng, X. F. Wu, Liang Li +2 · 2 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Cosmic Phenomena #Blast wave #Gamma-ray bursts and supernovae #Outflow #Relativistic quantum chemistry #Set (abstract data type) #Shock wave #Work (physics) #astro-ph.HE
paper · pdf · doi:10.1088/0004-637x/792/1/31
published as The Astrophysical Journal, 2014, 792, 31 · 23 pages, 5 Figures, accepted for publication in the Astrophysical Journal
arxiv created 2014/07/03 · openalex publication_date 2014/08/12 · openalex created_date 2016/06/24 · arxiv updated 2017/05/11 · openalex updated_date 2026/08/05
Re-brightening bumps are frequently observed in gamma-ray burst afterglows. Many scenarios have been proposed to interpret the origin of these bumps, of which a blast wave encountering a density-jump in the circumburst environment has been questioned by recent works. We develop a set of differential equations to calculate the relativistic outflow encountering the density-jump by extending the work of Huang et al. This approach is a semi-analytic method and is very convenient. Our results show that late high-amplitude bumps cannot be produced under common conditions, rather only a short plateau may emerge even when the encounter occurs at an early time (<10 4 s). In general, our results disfavor the density-jump origin for those observed bumps, which is consistent with the conclusion drawn from full hydrodynamics studies. The bumps thus should be caused by other scenarios.