Radiative lifetimes of even-parity high-lying levels of Sm I by delayed photoionization measurements

Radiative lifetimes of fifteen even-parity high-lying levels of atomic samarium in the energy range 34,000-34,815 cm−1 have been measured systematically. The measurements were carried out by detecting time-resolved delayed three-colour photoionization signal using pump-probe technique in an atomic beam coupled to a time-of-flight mass spectrometer. The measured values are in the range of 35 to 349 ns. Accuracy of the measurements was validated by measuring the lifetime of the first excited level used in the excitation scheme by employing two-colour pump-probe photoionization spectroscopy and comparing the measured value with that reported in the literature.