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arXiv · 2502.18718

Quantum Monte Carlo Calculations of neutron-$\alpha$ Scattering via an Integral Relation

Abraham R. Flores·Kenneth M. Nollett·Maria Piarulli
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Abstract

Nuclear physics seeks to describe both bound and unbound states within a unified predictive framework. While coordinate-space Quantum Monte Carlo (QMC) methods have successfully computed bound states for systems with $A \leq 12$, their application to unbound states remains limited. In this work, we extend the QMC approach to enable a broader range of unbound-state calculations. Our method infers long-range amplitudes in the wave function from integrals over the short-range interaction region. By evaluating these integrals using Green's Function Monte Carlo wave functions with the Argonne $v_{18}$ potential, we accurately reproduce existing results for neutron-alpha scattering. This approach provides a systematic pathway for studying more complex nuclear systems, including coupled-channel scattering and the effects of three-nucleon forces. It serves as a powerful tool for advancing $\textit{ab initio}$ calculations in nuclear reactions, paving the way for a unified framework that consistently describes both bound and scattering states within a single theoretical approach.

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Abraham R. Flores, Kenneth M. Nollett, Maria Piarulli. 2025-02-26. Quantum Monte Carlo Calculations of neutron-$\alpha$ Scattering via an Integral Relation. https://arxiv.org/abs/2502.18718

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