Laser spectroscopy of the 2S1/2-2P1/2, 2P3/2 transitions in stored and cooled relativistic C3+ ions

Abstract

The ${}^2{\mathrm{S}}_{1/2}{-}^2{\mathrm{P}}_{1/2}$ and ${}^2{\mathrm{S}}_{1/2}{-}^2{\mathrm{P}}_{3/2}$ transitions in Li-like carbon ions stored and cooled at a velocity of $\beta \approx 0.47$ in the experimental storage ring (ESR) at the GSI Helmholtz Centre in Darmstadt have been investigated in a laser spectroscopy experiment. Resonance wavelengths were obtained using a new continuous-wave UV laser system and a novel extreme UV (XUV) detection system to detect forward emitted fluorescence photons. The results obtained for the two transitions are compared to existing experimental and theoretical data. A discrepancy found in an earlier laser spectroscopy measurement at the ESR with results from plasma spectroscopy and interferometry has been resolved and agreement between experiment and theory is confirmed.