Tests of physics beyond the Standard Model with single-electron ions

TL;DR

This paper proposes a novel isotope shift spectroscopy method using single-electron ions to effectively search for new physics beyond the Standard Model, potentially improving bounds on electron couplings significantly.

Contribution

It introduces a weighted difference technique that suppresses nuclear uncertainties, enabling competitive bounds on new interactions with minimal experimental data.

Findings

Method can improve bounds on new physics by over an order of magnitude.

Requires only a single isotope pair for experimental measurements.

Feasible with advancements in UV/X-ray spectroscopy.

Abstract

A highly effective approach to the search for hypothetical new interactions through isotope shift spectroscopy of hydrogen-like ions is presented. A weighted difference of the g factor and ground-state energy is shown to assist in the suppression of detrimental uncertainties from nuclear structure, while preserving the hypothetical contributions from new interactions. Experimental data from only a single isotope pair is required. Account is taken of the small, subleading nuclear corrections, allowing to show that, provided feasible experimental progress is achieved in UV/X-ray spectroscopy, the presented approach can yield competitive bounds on New Physics electron coupling parameters improved by more than an order of magnitude compared to leading bounds from atomic physics.