Radiative lifetime measurements of the B²Σ⁺state of BaH by laser spectroscopy

Abstract

By applying laser resonance methods in the near infrared wavelength region around 900 nm, a time-resolved experiment has been performed on the low lying B 2Σ+ state of barium hydride. The radiative lifetime is shown to vary with the rotational quantum number due to perturbations between the low lying A' 2Δ, A 2Π and B 2Σ+ states. The following lifetime was obtained for the BaH molecule, where local perturbations are assumed to be negligible: τ(B 2Σ+(v' = 0, J = 5.5)) = 125 ± 2 ns.