Two- and three-dimensional simulations of core-collapse supernovae with CHIMERA

Ascertaining the core-collapse supernova mechanism is a complex, and yet unsolved, problem dependent on the interaction of general relativity, hydrodynamics, neutrino transport, neutrino-matter interactions, and nuclear equations of state and reaction kinetics. Ab initio modeling of core-collapse supernovae and their nucleosynthetic outcomes requires care in the coupling and approximations of the physical components. We have built our multi-physics CHIMERA code for supernova modeling in 1-, 2-, and 3-D, using ray-by-ray neutrino transport, approximate general relativity, and detailed neutrino and nuclear physics. We discuss some early results from our current series of exploding 2D simulations and our work to perform computationally tractable simulations in 3D using the "Yin-Yang" grid.Comment: Proceedings of the 12th Symposium on Nuclei in the Cosmos. 5-12 August 2012. Cairns, Australia. Published online at http://pos.sissa.it/archive/conferences/146/208/NIC%20XII_208.pdf Corrected typ

Advancing Nucleosynthesis in Self-consistent, Multidimensional Models of Core-Collapse Supernovae

We investigate core-collapse supernova (CCSN) nucleosynthesis in polar axisymmetric simulations using the multidimensional radiation hydrodynamics code CHIMERA. Computational costs have traditionally constrained the evolution of the nuclear composition in CCSN models to, at best, a 14-species $\alpha$-network. Such a simplified network limits the ability to accurately evolve detailed composition, neutronization and 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. Limitations such as poor spatial resolution of the tracer particles, estimation of the expansion timescales, and determination of the "mass-cut" at the end of the simulation impose uncertainties inherent to this approach. We present a detailed analysis of the impact of these uncertainties on post-processing nucleosynthesis calculations and implications for future models.Comment: Proceedings of the 13th Symposium on Nuclei in the Cosmos. 7-11 July 2014. Debrecen, Hungar