B2Σ+state lifetime in CO+

Abstract

We measured the lifetime of the B2Σ+, v = 0 level of the astrophysically important CO+molecule by applying the collinear beam-laser method. Ions in the long-lived A2Π level were excited to the B2Σ+state by a single-frequency laser beam in resonance with a transition in the B2Σ+– A2Π Baldet–Johnson band, and the laser-induced fluorescence from the B2Σ+– X2Σ+First Negative band was monitored as a function of distance from the excitation region. We claim that our result of 54.9 ± 0.7 ns is less likely to have suffered from systematic error than previous measurements, which were mutually discordant.PACS No. 33.70Ca