Abstract
Emission lines of the b 1+X̃ 3 transition of AsH radicals have been detected in the fluorescence of a dc‐glow‐discharge of arsine in hydrogen. From measurements of line positions of the (0,0), (1,1), and (2,2) Q branches and the (0,0) P and R branches, the molecular constants of the b 1+ state were determined: Te=14 178.0 cm−1, B0=7.2467 cm−1, D0=3.1528⋅10−4 cm−1, ωe=2213 cm−1, ωexe=47.5 cm−1, re=152.937 pm.