Accuracy estimation of the O216+ transition frequencies targeting the search for the variation in the proton-electron mass ratio

Abstract

The precise measurement of molecular vibrational transition frequencies is useful in the search for variation in the proton-to-electron mass ratio {\mu}. Homonuclear diatomic molecules are particularly advantageous for precise measurement because of the small Stark shift. This paper discusses the Stark and Zeeman shifts in the 16O2+ vibrational transition frequencies.To search for the variation {\mu}(<10-17/yr), the X2{\Pi}1/2(v,J)=(0,1/2)-(v',1/2)(v'>1)in transition frequencies are much more advantageous than the transition frequencies between the X2{\Pi}1/2 v=21 and a4{\Pi}1/2 v=0 states, whose sensitivity to the variation in {\mu} is high because of the accidental degeneracy.