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arXiv · 2312.09275

The Guided Moments formalism: a new efficient full-neutrino treatment for astrophysical simulations

Manuel R. Izquierdo·J. Fernando Abalos·Carlos Palenzuela
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Abstract

We present the new Guided Moments ($\texttt{GM}$) formalism for neutrino modeling in astrophysical scenarios like core-collapse supernovae and neutron star mergers. The truncated moments approximation ($\texttt{M1}$) and Monte-Carlo ($\texttt{MC}$) schemes have been proven to be robust and accurate in solving the Boltzmann's equation for neutrino transport. However, it is well-known that each method exhibits specific strengths and weaknesses in various physical scenarios. The $\texttt{GM}$ formalism effectively solves these problems, providing a comprehensive scheme capable of accurately capturing the optically thick limit through the exact $\texttt{M1}$ closure and the optically thin limit through a $\texttt{MC}$ based approach. In addition, the $\texttt{GM}$ method also approximates the neutrino distribution function with a reasonable computational cost, which is crucial for the correct estimation of the different neutrino-fluid interactions. Our work provides a comprehensive discussion of the formulation and application of the $\texttt{GM}$ method, concluding with a thorough comparison across several test problems involving the three schemes ($\texttt{M1}$, $\texttt{MC}$, $\texttt{GM}$) under consideration.

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Manuel R. Izquierdo, J. Fernando Abalos, Carlos Palenzuela. 2023-12-14. The Guided Moments formalism: a new efficient full-neutrino treatment for astrophysical simulations. https://doi.org/10.1103/physrevd.109.043044

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