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arXiv · 2306.12131

A Poincar\'e covariant cascade method for high-energy nuclear collisions

Yasushi Nara·Asanosuke Jinno·Tomoyuki Maruyama·Koichi Murase·Akira Ohnishi
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Abstract

We present a Poincar\'e covariant cascade algorithm based on the constrained Hamiltonian dynamics in an $8N$-dimensional phase space to simulate the Boltzmann-type two-body collision term. We compare this covariant cascade algorithm with traditional $6N$-dimensional phase-space cascade algorithms. To validate the covariant cascade algorithm, we perform box calculations. We examine the frame dependence of the algorithm in a one-dimensionally expanding system as well as the compression stages of colliding two nuclei. We confirm that our covariant cascade method is reliable to simulate high-energy nuclear collisions. Furthermore, we present Lorentz-covariant equations of motion for the $N$-body system interacting via potentials, which can be efficiently solved numerically.

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Yasushi Nara, Asanosuke Jinno, Tomoyuki Maruyama, Koichi Murase, Akira Ohnishi. 2023-06-21. A Poincar\'e covariant cascade method for high-energy nuclear collisions. https://doi.org/10.1103/physrevc.108.024910

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