Spectroscopy of light atoms and bounds on physics beyond the standard model

TL;DR

This paper uses high-precision spectroscopic data of light atoms to set new bounds on possible fifth-force interactions between electrons and nucleons, providing constraints on physics beyond the standard model.

Contribution

It presents novel bounds on electron-proton and electron-neutron couplings from spectroscopic data, independent of specific nuclear coupling assumptions.

Findings

New bounds on fifth-force couplings derived from hydrogen, deuterium, helium-3, and helium-4 spectroscopy.

Constraints are independent of assumptions about nuclear coupling differences.

Results are relevant for carrier masses below 100 keV.

Abstract

Newly calculated bounds on the strength of the coupling of an electron to a proton or a neutron by a fifth force are presented. These results are derived from the high precision spectroscopic data currently available for hydrogen, deuterium, helium-3 and helium-4. They do not depend on specific assumptions on how the interaction would couple to a deuteron compared to a proton or would couple to an $\alpha$ particle compared to a helion. They depend on its coupling to a muon, but not in a significant way for carrier masses below 100~keV if one assumes that the strength of the interaction with a muon would be of a similar order of magnitude as the strength of the interaction with an electron in that mass region.