Ko Nakamura, Tomoya Takiwaki, Kei Kotake, Nobuya Nishimura
We explore potential impacts of nuclear burning on assisting an onset of the neutrino-driven explosions of core-collapse supernovae. By changing the neutrino luminosity and its decay time to obtain parametric explosions in 1D and 2D models with or without a 13-isotope alpha network, we study how the inclusion of nuclear burning could affect the postbounce dynamics for four progenitor models. We find that the energy supply due to nuclear burning of infalling material behind the shock can energize the shock expansion especially for models that produce only marginal explosions in the absence of nuclear burning. These models enjoy the assistance from nuclear burning typically in the following two ways, whether the shock front passes through the silicon-rich layer, or later it touches to the oxygen-rich layer. Depending on the neutrino luminosity and its decay time, the explosion energy increases up to a few times 10^50 erg for models with nuclear burning compared to the corresponding models without. The difference in the explosion energy is generally smaller in 2D than in 1D, because neutrino-driven convection and the SASI in 2D models enhance the neutrino heating efficiency, which makes the contribution of nuclear burning relatively smaller compared to 1D models. We point out that these features are remarkable only for the Limongi-Chieffi progenitor both in 1D and 2D, which possesses a massive oxygen layer with its inner-edge radius being smallest among the employed progenitors, so that the shock can touch to the rich fuel on a shorter timescale after bounce. Considering uncertainties in progenitor models, our results indicate that nuclear burning should remain as one of the unignorable ingredients to foster the onset of neutrino-driven explosions.
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http://arxiv.org/abs/1207.5955
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