Neutron-antineutron oscillations in the deuteron studied with $NN$ and $\bar NN$ interactions based on chiral effective field theory

TL;DR

This paper calculates the deuteron lifetime due to neutron-antineutron oscillations using chiral effective field theory, comparing results with previous models and discussing discrepancies.

Contribution

It provides a non-perturbative EFT calculation of deuteron lifetime related to n-anti n oscillations, highlighting differences from perturbative approaches.

Findings

Deuteron lifetime formula: (2.6±0.1)×10^{22} τ_{n-anti n}^2 seconds.

Close to earlier non-EFT estimates, but differs from recent EFT perturbative results.

Discusses potential reasons for discrepancies with other EFT calculations.

Abstract

Neutron-antineutron ($n-\bar n$) oscillations in the deuteron are considered. Specifically, the deuteron lifetime is calculated in terms of the free-space $n-\bar n$ oscillation time $\tau_{n-\bar n}$ based on $NN$ and $\bar NN$ interactions derived within chiral effective field theory (EFT). This results in $(2.6\pm 0.1) \times 10^{22}\,\tau^2_{n-\bar n}$ s, which is close to the value obtained by Dover and collaborators more than three decades ago, but disagrees with recent EFT calculations that were performed within the perturbative scheme proposed by Kaplan, Savage, and Wise. Possible reasons for the difference are discussed.