Jet simulations and gamma-ray burst afterglow jet breaks
| Autor: | van Eerten, H.J., Meliani, Z., Wijers, Ramj, Keppens, R. |
|---|---|
| Přispěvatelé: | Astrophysics, Dep Natuurkunde, High Energy Astrophys. & Astropart. Phys (API, FNWI) |
| Jazyk: | angličtina |
| Rok vydání: | 2011 |
| Předmět: |
High Energy Astrophysical Phenomena (astro-ph.HE)
non-thermal shock waves gamma-ray burst: general gamma-ray burst: individual: GRB030329 X-rays: general [hydrodynamics radiation mechanisms] Astrophysics::High Energy Astrophysical Phenomena FOS: Physical sciences Astrophysics - High Energy Astrophysical Phenomena |
| Zdroj: | van Eerten, H J, Meliani, Z, Wijers, R A M J & Keppens, R 2011, ' Jet simulations and gamma-ray burst afterglow jet breaks ', Monthly Notices of the Royal Astronomical Society, vol. 410, no. 3, pp. 2016-2024 . https://doi.org/10.1111/j.1365-2966.2010.17582.x Monthly Notices of the Royal Astronomical Society, 410, 2016-2024 Monthly Notices of the Royal Astronomical Society, 410(3), 2016-2024. Oxford University Press |
| ISSN: | 0035-8711 |
| DOI: | 10.1111/j.1365-2966.2010.17582.x |
| Popis: | The conventional derivation of the gamma-ray burst afterglow jet break time uses only the blast wave fluid Lorentz factor and therefore leads to an achromatic break. We show that in general gamma-ray burst afterglow jet breaks are chromatic across the self-absorption break. Depending on circumstances, the radio jet break may be postponed significantly. Using high-accuracy adaptive mesh fluid simulations in one dimension, coupled to a detailed synchrotron radiation code, we demonstrate that this is true even for the standard fireball model and hard-edged jets. We confirm these effects with a simulation in two dimensions. The frequency dependence of the jet break is a result of the angle dependence of the emission, the changing optical depth in the self-absorbed regime and the shape of the synchrotron spectrum in general. In the optically thin case the conventional analysis systematically overestimates the jet break time, leading to inferred opening angles that are underestimated by a factor 1.32 and explosion energies that are underestimated by a factor 1.73, for explosions in a homogeneous environment. MNRAS submitted. 9 pages, 12 figures |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text