Energy dissipation below gamma-ray bursts photosphere: evidence and spectral fits
| dc.contributor.author | Pe'er, Asaf | |
| dc.date.accessioned | 2019-01-25T12:43:29Z | |
| dc.date.available | 2019-01-25T12:43:29Z | |
| dc.date.issued | 2015-07 | |
| dc.date.updated | 2019-01-25T12:08:00Z | |
| dc.description.abstract | It is now established that a thermal emission component plays a major role in shaping the prompt spectra of a non-negligible fraction of gamma-ray bursts (GRBs). By studying the properties of this component in a sample of 47 GRBs, we deduce that the Lorentz factor is 102 ≲ Γ ≲ 103, with mean value 〈Γ〉 ≃ 370. The acceleration radius r0 span a wide range, 106.5 ≲ r0 ≲ 109.5 cm, with mean value 〈r0〉 ≃ 108 cm. This is higher than the gravitational radius of 10 M⊙ black hole by a factor of ≈ 30. We argue that this result provides an indirect evidence for jet propagation inside a massive star, and suggests the existence of recollimation shocks that take place at this radius. We further show that sub-photospheric dissipation of the jet kinetic energy provides a self-consistent, fully physically motivated model that can fit a wide range of GRB spectra. The leading radiative process is Comptonization of the thermal component, and synchrotron emission is sub-dominant. We create a DREAM (Dissipation with Radiative Emission as a Table Model) table model for XSPEC, and show how this model can describe different types of GRB spectra. | en |
| dc.description.status | Peer reviewed | en |
| dc.description.version | Published Version | en |
| dc.format.mimetype | application/pdf | en |
| dc.identifier.citation | Pe'er, A. (2015) 'Energy dissipation below gamma-ray bursts photosphere: evidence and spectral fits', Proceedings of the Fourteenth Marcel Grossmann Meeting on General Relativity, Rome, Italy, 12-18 July, pp. 2943-2949. Available at: https://doi.org/10.1142/10614 (Accessed 25 January 2019) | en |
| dc.identifier.endpage | 2949 | en |
| dc.identifier.isbn | 978-981-3226-59-3 | |
| dc.identifier.startpage | 2943 | en |
| dc.identifier.uri | https://hdl.handle.net/10468/7361 | |
| dc.language.iso | en | en |
| dc.publisher | World Scientific | en |
| dc.relation.ispartof | Fourteenth Marcel Grossmann Meeting on General Relativity | |
| dc.relation.uri | https://doi.org/10.1142/10614 | |
| dc.rights | © 2015, Asaf Pe’er. This paper is distributed under the terms of the Creative Commons Attribution 4.0 (CC BY) License. Further distribution of this work is permitted, provided the original work is properly cited. | en |
| dc.rights.uri | https://creativecommons.org/licenses/by/4.0/ | en |
| dc.subject | Gamma-rays | en |
| dc.subject | Bursts | en |
| dc.subject | Hydrodynamics | en |
| dc.subject | Radiation mechanism | en |
| dc.subject | Non-thermal | en |
| dc.subject | Thermal | en |
| dc.title | Energy dissipation below gamma-ray bursts photosphere: evidence and spectral fits | en |
| dc.type | Conference item | en |
