Spectroscopic Shifts in Deuterated Methanol Induced by Variation of me/mp

TL;DR

This paper calculates how microwave transitions in deuterated methanol are sensitive to tiny variations in the electron-to-proton mass ratio, providing a potential tool for detecting fundamental constant changes related to dark matter and energy.

Contribution

It provides new theoretical calculations of sensitivity coefficients for deuterated methanol transitions to variations in mu, highlighting their potential for fundamental physics tests.

Findings

Sensitivity coefficients range from -300 to +73.

Deuterated methanol transitions are promising for detecting small changes in mu.

Several outliers in sensitivity coefficients were identified with unclear origins.

Abstract

Numerical calculations of the sensitivity coefficients, Q_mu, of microwave molecular transitions in the ground torsion-rotation state of deuterated methanol (CH3OD, CD3OH, and CD3OD) to small variations in the fundamental physical constant mu = me/mp - the electron-to-proton mass ratio - are reported. Theoretical motivation for changes in mu comes from a variety of models beyond the Standard Model of particle physics which are invoked to explain the nature of dark matter and dark energy that dominate the Universe. The calculated values of Q_mu range from -300 to +73 and, thus, make deuterated methanol promising for searches for small space-time changes in mu. It is also shown that among the calculated sensitivity coefficients Q_mu using different Hamiltonians in the present and previous works, there are several pronounced outliers of unclear nature.