Constraints on exotic interactions from scalar spin-spin coupling in tritium deuteride (DT)

TL;DR

This study uses scalar spin-spin coupling measurements in tritium deuteride to set new constraints on exotic nucleon-nucleon interactions mediated by hypothetical bosons, improving limits on their coupling strengths.

Contribution

First to constrain $g_V g_V$ couplings via analysis of potential terms in tritium deuteride and hydrogen deuteride molecules.

Findings

Proton-nucleon coupling $g_V^p g_V^N$ less than $1.4 imes 10^{-6}$ at 5 keV boson mass.

Proton-nucleon pseudoscalar coupling $g_p^p g_p^N$ less than $2.7 imes 10^{-6}$ at 5 keV.

Axial-vector coupling $g_A^p g_A^N$ less than $1.0 imes 10^{-18}$ for boson masses ≤ 100 eV.

Abstract

A comparison of theoretical and experimental values of the scalar spin-spin interaction ($J$-coupling) in tritium deuteride molecules yield constraints for nucleon-nucleon exotic interactions of the dimensionless coupling strengths $g_Vg_V$, $g_Ag_A$ and $g_pg_p$, corresponding to the exchange of an vector, axial-vector, and pseudoscalar (axionlike) boson. The couplings between proton ($p$) and nucleon ($N$), denoted by $g_V^p g_V^N$, $g_p^p g_p^N$ are constrained to be less than $1.4 \times 10^{-6}$ and $2.7\times 10^{-6}$, respectively, for boson masses around 5 keV. The coupling constant $g_A^p g_A^N$ is constrained to be less than $1.0 \times 10^{-18}$ for boson masses $\leq 100$ eV. It is noteworthy that this study represents the first instance in which constraints on $g_V g_V$ have been established through the analysis of the potential term $V_2 + V_3$ for both tritium deuteride and hydrogen deuteride molecules.