Isotope-shift measurements in Ca+

摘要: We have measured the optical shifts for all stable isotopes of ${\mathrm{Ca}}^{+}$, with respect to isotope mass 40, in resonance transitions 4s $^{2}$${\mathit{S}}_{1/2}$--4p $^{2}$${\mathit{P}}_{1/2,3/2}$. The value our shift even 46 falls below King plot. From fit a second plot, omitting 46, we obtain -312 MHz ${\mathrm{fm}}^{\mathrm{\ensuremath{-}}2}$ field-shift constant F. A comparison this ab initio calculations [G. Torbohm, B. Fricke, and A. Rosen, Phys. Rev. 31, 2038 (1985)] semiempirical estimate shows better agreement when correlation effects been included [A.-M. Martensson-Pendrill, Ynnerman, H. Warston (private communication)] suggests that inclusion screening factor \ensuremath{\beta} methods results an overestimate