Change search
ReferencesLink to record
Permanent link

Direct link
THE ANATOMY OF A LONG GAMMA-RAY BURST: A SIMPLE CLASSIFICATION SCHEME FOR THE EMISSION MECHANISM(S)
Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
Stockholm University, Faculty of Science, The Oskar Klein Centre for Cosmo Particle Physics (OKC).
Number of Authors: 2
2016 (English)In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 820, no 1, 68Article in journal (Refereed) Published
Abstract [en]

Ultra-relativistic motion and efficient conversion of kinetic energy to radiation are required by gamma-ray burst (GRB) observations, yet they are difficult to simultaneously achieve. Three leading mechanisms have been proposed to explain the observed emission emanating from GRB outflows: radiation from either relativistic internal or external shocks, or thermal emission from a photosphere. Previous works were dedicated to independently treating these three mechanisms and arguing for a sole, unique origin of the prompt emission of GRBs. In contrast, herein, we first explain why all three models are valid mechanisms and that a contribution from each of them is expected in the prompt phase. Additionally, we show that a single parameter, the dimensionless entropy of the GRB outflow, determines which mechanism contributes the most to the emission. More specifically, internal shocks dominate for low values of the dimensionless entropy, external shocks for intermediate values, and finally, photospheric emission for large values. We present a unified framework for the emission mechanisms of GRBs with easily testable predictions for each process.

Place, publisher, year, edition, pages
2016. Vol. 820, no 1, 68
Keyword [en]
gamma-ray burst: general, radiation mechanisms: general, radiation mechanisms: non-thermal
National Category
Physical Sciences
Identifiers
URN: urn:nbn:se:su:diva-129677DOI: 10.3847/0004-637X/820/1/68ISI: 000372787000067OAI: oai:DiVA.org:su-129677DiVA: diva2:930326
Available from: 2016-05-23 Created: 2016-04-27 Last updated: 2016-05-23Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text
By organisation
The Oskar Klein Centre for Cosmo Particle Physics (OKC)
In the same journal
Astrophysical Journal
Physical Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 5 hits
ReferencesLink to record
Permanent link

Direct link