Theoretical study of the NO b 4Σ − and O +2 b 4Σ −g radiative lifetimes

Abstract

We have computed the radiative lifetime of the NO b 4Σ − state, which is determined by the 4Σ −−a 4Π Ogawa band system. Analogous calculations were carried out for the O + 2 b 4Σ − g−a 4Π u first negative band system. Calibration calculations of both the one- and n-particle spaces are used to demonstrate that the theoretical lifetimes are accurate to 10%. The O + 2 4Σ − g radiative lifetimes are in excellent agreement with previous theoretical calculations and with the experimental values of Erman and Larsson. The theoretical NO b 4Σ − radiative lifetimes are consistent with our previous theoretical results, but significantly longer than the experimental values, suggesting that some decay mechanism other than the Ogawa system is contributing to the lifetime.