Ab initio alpha-alpha scattering

TL;DR

This paper presents the first ab initio calculation of alpha-alpha scattering using lattice effective field theory and the adiabatic projection method, achieving good agreement with experimental data and indicating potential for studying heavier nuclei.

Contribution

It introduces a novel ab initio approach to alpha-alpha scattering, combining lattice EFT with the adiabatic projection method for the first time.

Findings

Good agreement with experimental phase shifts for S-wave and D-wave.

Computational scaling suggests feasibility for heavier nuclei.

First ab initio calculation of alpha-alpha scattering.

Abstract

Processes involving alpha particles and alpha-like nuclei comprise a major part of stellar nucleosynthesis and hypothesized mechanisms for thermonuclear supernovae. In an effort towards understanding alpha processes from first principles, we describe in this letter the first ab initio calculation of alpha-alpha scattering. We use lattice effective field theory to describe the low-energy interactions of nucleons and apply a technique called the adiabatic projection method to reduce the eight-body system to an effective two-cluster system. We find good agreement between lattice results and experimental phase shifts for S-wave and D-wave scattering. The computational scaling with particle number suggests that alpha processes involving heavier nuclei are also within reach in the near future.