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Enhanced Sensitivity to Variation of me/mp in Molecular Spectra
Published
Author(s)
D DeMille, S Sainis
Abstract
We propose new experiments with high sensitivity to a variation in the electron-to-proton mass ratio \mu=me/mp. We consider a close pair of molecular vibrational levels, where each state is associated with a different electronic potential. The change in the splitting between such levels, with respect to a change in \mu, can be large both on an absolute scale, and relative to the splitting. We demonstrate the existence of such pairs of levels in Cs_2. The narrow spectral lines achievable with ultracold Cs2 in the long-lived levels make this system promising for future searches for small variations in \mu.
Citation
Physical Review Letters
Pub Type
Journals
Keywords
cesium, fundamental constants, molecular physics, ultra-cold atoms
Citation
DeMille, D.
and Sainis, S.
(2008),
Enhanced Sensitivity to Variation of m<sub>e</sub>/m<sub>p</sub> in Molecular Spectra, Physical Review Letters
(Accessed October 26, 2025)