Lifetime, collisional-quenching, andj-mixing measurements of the metastable 3Dlevels ofCa+

The metastable $3^2$ ${\mathit{D}}_{3/2,5/2}$ doublet of ${\mathrm{Ca}}^{+}$ ions stored in a Paul trap was investigated in the presence of different neutral gases, in the pressure range ${10}^{\mathrm{-}9}$–${10}^{\mathrm{-}6}$ mbar. The natural lifetimes were determined to be τ(${\mathit{D}}_{3/2}$)=1111±46 ms and τ(${\mathit{D}}_{5/2}$)=994±38 ms, which agree very well with previous experiments. The estimation of the quenching rates of ${\mathrm{Ca}}^{+}$-He [${\mathrm{\Gamma }}_{\mathrm{He}}$=(1.05±0.42)×${10}^{\mathrm{-}12}$ ${\mathrm{cm}}^3$ ${\mathrm{s}}^{\mathrm{-}1}$], ${\mathrm{Ca}}^{+}$-Ne [${\mathrm{\Gamma }}_{\mathrm{}\mathrm{Ne}}$=(0.9±0.7)×${10}^{\mathrm{-}12}$ ${\mathrm{cm}}^3$ ${\mathrm{s}}^{\mathrm{-}1}$], and ${\mathrm{Ca}}^{+}$-${\mathrm{N}}_2$ [${\mathrm{\Gamma }}_{{\mathrm{N}}_2}$=(1.7±0.2)×${10}^{\mathrm{-}10}$ ${\mathrm{cm}}^3$ ${\mathrm{s}}^{\mathrm{-}1}$] was carried out for collisions in the energy range 0.3–1.3 eV. In addition, rate constants for the mixing of the fine-structure states were measured in the presence of helium and nitrogen for the j=3/2→j=5/2 case [${\gamma }_{35}$(He)=(2.24±0.10)×${10}^{\mathrm{-}10}$ ${\mathrm{cm}}^3$ ${\mathrm{s}}^{\mathrm{-}1}$ and ${\gamma }_{35}$(${\mathrm{N}}_2$)=(2.8±0.3)×