Radiative lifetimes in W I using a novel atomic-beam source

Abstract

The first direct radiative lifetime measurements in W I are described. Radiative lifetimes of 15 levels from the $5{d}^{4}6s(a^{6}D)6p(z^{7}D^{0})$, $5{d}^{4}6s(a^{6}D)6p(z^{5}F^{0})$, $5{d}^{5}(a^{6}S)6p(z^{7}P^{0})$,, and $5{d}^{4}6s(a^{6}D)6p(z^{5}P^{0})$ terms are reported with an accuracy of \ifmmode\pm\else\textpm\fi{}5%. The lifetimes are measured using time-resolved laser-induced fluorescence and a novel atomic-beam source. This novel hollow cathode effusive beam source produces an intense beam of ground-state W atoms and metastable W atoms.