Sensitivity of transitions in internal rotor molecules to a possible variation of the proton-to-electron mass ratio

摘要

Recently, methanol was identified as a sensitive target system to probe variations of the proton-to-electron mass ratio μ. The high sensitivity of methanol originates from the interplay between overall rotation and hindered internal rotation of the molecule; that is, transitions that convert internal rotation energy into overall rotation energy, or vice versa, have an enhanced sensitivity coefficient, K