Measurements of radiative-decay rates of the 2${\mathit{s}}^2$2p${(}^2$P°)-2s2${\mathit{p}}^2$${(}^4$P) intersystem transitions of ${\mathrm{C}}^{+}$

The radiative-decay rates of the 2${\mathit{s}}^2$2p${(}^2$ ${\mathit{P}}^0$)-2s2${\mathit{p}}^2$ ${(}^4$P) intersystem transitions of ${\mathrm{C}}^{+}$ ions have been measured by recording the time dependence of the ∼233-nm emission. A cylindrical radio-frequency ion trap was used to store electron-impact-produced ${\mathrm{C}}^{+}$ ions. The time-dependent signals were analyzed by multiexponential least-squares fits to the data. The measured radiative-decay rates to the ground term are 146.4(+8.3,-9.2) ${\mathrm{s}}^{\mathrm{-}1}$ for ${}_{}{}^4{}_{}{}^{}\mathrm{P}_{1/2}^{}{}_{}{}^{}$, 11.6(+0.8,-1.7) ${\mathrm{s}}^{\mathrm{-}1}$ for ${}_{}{}^4{}_{}{}^{}$ ${\mathit{P}}_{3/2}$, and 51.2(+2.6,-3.5) ${\mathrm{s}}^{\mathrm{-}1}$ for ${}_{}{}^4{}_{}{}^{}$ ${\mathit{P}}_{5/2}$. Comparison of the measured values with theoretical values is presented.