Radiative lifetimes are measured for metastable levels in the iron charge states ${\mathrm{Fe}}^{9+},{\mathrm{Fe}}^{10+}$, and ${\mathrm{Fe}}^{13+}$. The ions are generated in a 14 GHz electron cyclotron resonance ion source and trapped in a Kingdon ion trap. The Fe levels and their measured lifetimes are (a) $73.0\pm 0.8\mathrm{ms}$ for the $3s^{2}3p^4\left({}^{3}P\right)3d$ ${}^{4}F_{7∕2}$ level in ${\mathrm{Fe}}^{9+}$, (b) $9.91\pm 0.5\mathrm{ms}$ for the $3s^{2}3p^4$ ${}^{1}D_2$ level in ${\mathrm{Fe}}^{10+}$, and (c) $17.0\pm 0.2\mathrm{ms}$ for the $3s^{2}3p$ ${}^{2}P^o{}_{3∕2}$ level in ${\mathrm{Fe}}^{13+}$. Comparisons are made to other measured results using a Kingdon trap, an ion storage, and an electron-beam ion trap (EBIT).

• Received 28 September 2005

DOI:https://doi.org/10.1103/PhysRevA.72.062504