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Enhanced sensitivity to variation of $m_{e}/m_{p}$ in molecular spectra

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 نشر من قبل David DeMille
 تاريخ النشر 2007
  مجال البحث فيزياء
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We propose new experiments with high sensitivity to a possible spatial or temporal variation of the electron-to-proton mass ratio $mu equiv m_e/m_p$. We consider a nearly-degenerate 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 Cs$_2$ in these long-lived levels make this system promising for future searches for small variations in $mu$.



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