Detection of rotational lines of NaSH molecule

Abstract

Laboratory detection of NaSH molecule in absorption has been reported by Kagi &amp; Kawaguchi, <i>Astrophys J </i>,<i> </i>491 (1997) L129. They observed only <i>a</i>-type rotational transitions of the molecule. The reason for not observing <i>b</i>-type rotational transitions was assigned to a small value of <i>b</i>-component of electric dipole moment (μ_b = 0.63 D) as compared to <i>a</i>-component of electric dipole moment (μ_a = 8.91 D) of the molecule. The <i>b</i>-type transitions may be detected in emission in interstellar medium having low densities. However, it is not feasible to detect <i>b</i>-type rotational transitions in the absorption spectrum.