Radiative lifetime measurements of highly excited even-parity levels of Eu I

Natural radiative lifetime measurements have been performed for 186 even-parity highly excited levels of neutral europium in the energy range from 27852.90 to 45106.83 cm-1 using a time-resolved laser-induced fluorescence technique in a laser-produced plasma. This work is the largest-scale laboratory study to date of Eu i radiative lifetimes using modern methods. The lifetime values measured in this paper are in the range from 17.0 to 3569 ns. Comparison with previous data reveals a good level of agreement. Unique J-values of the 43438.19- and 43637.11-cm-1 levels have been assigned. The present work will be useful for extending the set of oscillator strengths available for Eu i.