Muonic Lithium atoms: nuclear structure corrections to the Lamb shift

TL;DR

This paper develops an ab initio theoretical framework to accurately compute nuclear structure corrections to the Lamb shift in muonic Lithium atoms, aiding precise charge radius measurements relevant to fundamental puzzles.

Contribution

It introduces the first steps towards ab initio calculations of nuclear corrections in muonic Lithium, improving upon large-uncertainty estimates from experimental data.

Findings

Initial ab initio methods applied to muonic Lithium systems.

Provides more precise nuclear correction estimates for future Lamb shift measurements.

Lays groundwork for resolving charge radius discrepancies.

Abstract

In view of the future plans to measure the Lamb shift in muonic Lithium atoms we address the microscopic theory of the $\mu$-$^6$Li$^{2+}$ and $\mu$-$^7$Li$^{2+}$ systems. The goal of the CREMA collaboration is to measure the Lamb shift to extract the charge radius with high precision and compare it to electron scattering data or atomic spectroscopy to see if interesting puzzles, such as the proton and deuteron radius puzzles, arise. For this experiment to be successful, theoretical information on the nuclear structure corrections to the Lamb shift is needed. For $\mu$-$^6$Li$^{2+}$ and $\mu$-$^7$Li$^{2+}$ there exist only estimates of nuclear structure corrections based on experimental data that suffer from very large uncertainties. We present the first steps towards an ab initio computation of these quantities using few-body techniques.