Radiative lifetimes, branching fractions, and oscillator strengths of some levels in Be I

Abstract

Radiative lifetimes of five levels in Be I lying in the energy range 64,506.45–71,160.52 cm−1 were measured by the time-resolved laser-induced fluorescence technique. These new data, together with previously measured radiative lifetimes and two reliable calculated lifetimes, were combined with branching fractions obtained from pseudo-relativistic Hartree–Fock calculations to deduce semi-empirical transition probabilities and oscillator strengths for 90 Be I spectral lines involving upper levels ranging from 42,565.35 to 72,251.27 cm−1.