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Implications for Post-Processing Nucleosynthesis of Core-Collapse Supernova Models with Lagrangian Particles

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 نشر من قبل J. Austin Harris
 تاريخ النشر 2017
  مجال البحث فيزياء
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We investigate core-collapse supernova (CCSN) nucleosynthesis with self-consistent, axisymmetric (2D) simulations performed using the radiation-hydrodynamics code Chimera. Computational costs have traditionally constrained the evolution of the nuclear composition within multidimensional CCSN models to, at best, a 14-species $alpha$-network capable of tracking only $(alpha,gamma)$ reactions from $^{4}$He to $^{60}$Zn. Such a simplified network limits the ability to accurately evolve detailed composition and neutronization or calculate the nuclear energy generation rate. Lagrangian tracer particles are commonly used to extend the nuclear network evolution by incorporating more realistic networks in post-processing nucleosynthesis calculations. However, limitations such as poor spatial resolution of the tracer particles, inconsistent thermodynamic evolution, including misestimation of expansion timescales, and uncertain determination of the multidimensional mass-cut at the end of the simulation impose uncertainties inherent to this approach. We present a detailed analysis of the impact of such uncertainties for four self-consistent axisymmetric CCSN models initiated from stellar metallicity, non-rotating progenitors of 12 $M_odot$, 15 $M_odot$, 20 $M_odot$, and 25 $M_odot$ and evolved with the smaller $alpha$-network to more than 1 s after the launch of an explosion.



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