REVISITING THE EMISSION FROM RELATIVISTIC BLAST WAVES IN A DENSITY-JUMP MEDIUM
2014 (English)In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 792, no 1, 31- p.Article in journal (Refereed) Published
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.
Place, publisher, year, edition, pages
2014. Vol. 792, no 1, 31- p.
gamma-ray burst: general, hydrodynamics, radiation mechanisms: non-thermal, shock waves
Astronomy, Astrophysics and Cosmology
IdentifiersURN: urn:nbn:se:su:diva-107792DOI: 10.1088/0004-637X/792/1/31ISI: 000341172100031OAI: oai:DiVA.org:su-107792DiVA: diva2:753019