Probing "long-range" neutrino-mediated forces with atomic and nuclear spectroscopy

TL;DR

This paper investigates how neutrino pair exchange can produce a long-range force detectable through atomic and nuclear spectroscopy, setting new constraints and suggesting future experimental prospects.

Contribution

It calculates the effects of neutrino-pair exchange on atomic and nuclear energies and derives the most stringent limits to date on such forces from spectroscopic data.

Findings

Limits on neutrino-mediated forces improve previous constraints by 18 orders of magnitude.

Atomic s-wave states show enhanced energy shifts due to the neutrino potential.

Future spectroscopy could detect or further constrain long-range neutrino-mediated interactions.

Abstract

The exchange of a pair of low-mass neutrinos between electrons, protons and neutrons produces a "long-range" $1/r^5$ potential, which can be sought for in phenomena originating on the atomic and sub-atomic length scales. We calculate the effects of neutrino-pair exchange on transition and binding energies in atoms and nuclei. In the case of atomic s-wave states, there is a large enhancement of the induced energy shifts due to the lack of a centrifugal barrier and the highly singular nature of the neutrino-mediated potential. We derive limits on neutrino-mediated forces from measurements of the deuteron binding energy and transition energies in positronium, muonium, hydrogen and deuterium, as well as isotope-shift measurements in calcium ions. Our limits improve on existing constraints on neutrino-mediated forces from experiments that search for new macroscopic forces by 18 orders of magnitude. Future spectroscopy experiments have the potential to probe long-range forces mediated by the exchange of pairs of standard-model neutrinos and other weakly-charged particles.