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arXiv · 0808.3905

Rebound Shock Breakouts of Exploding Massive Stars: A MHD Void Model

Ren-Yu Hu·Yu-Qing Lou
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Abstract

With a self-similar magnetohydrodynamic (MHD) model of an exploding progenitor star and an outgoing rebound shock and with the thermal bremsstrahlung as the major radiation mechanism in X-ray bands, we reproduce the early X-ray light curve observed for the recent event of XRO 080109/SN 2008D association. The X-ray light curve consists of a fast rise, as the shock travels into the "visible layer" in the stellar envelope, and a subsequent power-law decay, as the plasma cools in a self-similar evolution. The observed spectral softening is naturally expected in our rebound MHD shock scenario. We propose to attribute the "non-thermal spectrum" observed to be a superposition of different thermal spectra produced at different layers of the stellar envelope.

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Ren-Yu Hu, Yu-Qing Lou. 2008-08-28. Rebound Shock Breakouts of Exploding Massive Stars: A MHD Void Model. https://doi.org/10.1063/1.3027936

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