Lifetime Measurement of Highly Charged Ions Relevant to Astrophysics

Abstract

We have measured the $1\mathrm{s}2\mathrm{s}2\mathrm{p}{}^4{\mathrm{P}}_{5/2}^0$-$1{\mathrm{s}}^{2}2\mathrm{s}{}^2{\mathrm{S}}_{1/2}$ magnetic quadrupole X-ray transition energy in Li-like Fe along with the $1\mathrm{s}2\mathrm{s}{}^3{\mathrm{S}}_1$-$1{\mathrm{s}}^2{}^1{\mathrm{S}}_0$ transition energy in He-like Fe using multi channel doppler tuned spectrometer. These states have been produced through the interaction of 165 MeV Fe${}^{12+}$ ion beam with 100 $\mu$g/cm${}^2$ thin carbon foil. Further we have measured the lifetime of $1\mathrm{s}2\mathrm{s}2\mathrm{p}{}^4{\mathrm{P}}_{5/2}^0$ level in Li-like Fe. The measured transition energy of $1\mathrm{s}2\mathrm{s}{}^3{\mathrm{S}}_1$-$1{\mathrm{s}}^2{}^1{\mathrm{S}}_0$ is in good agreement with the available theoretical predictions and experimental measurements, whereas the measurement of $1\mathrm{s}2\mathrm{s}2\mathrm{p}{}^4{\mathrm{P}}_{5/2}^0$-$1{\mathrm{s}}^{2}2\mathrm{s}{}^2{\mathrm{S}}_{1/2}$ energy is little lower than the theoretical estimations. However, the measured lifetime of $1\mathrm{s}2\mathrm{s}2\mathrm{p}{}^4{\mathrm{P}}_{5/2}^0$ level compares well with the theoretical predictions.