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Enhanced Sensitivity to Variation of me/mp in Molecular Spectra



D DeMille, S Sainis


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.
Physical Review Letters


cesium, fundamental constants, molecular physics, ultra-cold atoms


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 July 14, 2024)


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Created October 16, 2008