The electric dipole moment of NO A  2Σ+  v ′=0 measured using Stark quantum-beat spectroscopy

We report measurements and analysis of Stark quantum beats observed in the fluorescence of nitric oxide (NO) from which we determine the electric dipole moment of the A 2Σ+ v′=0 state. A pulse-amplified cw dye laser was used to excite the A–X (0,0) Q1(1) transition of 14N16O in electric fields up to 22.5 kV/cm. Fourier analysis of the time-resolved laser-induced fluorescence signals yielded Stark tunings for each of the six ‖MF‖ hyperfine sublevels in the N=1, J=3/2 spin-rotational level. The measurements were fit to a model Hamiltonian including fine, hyperfine, and Stark matrix elements. The resulting dipole moment was then corrected for polarizability effects to yield a value for the A 2Σ+ v′=0 state of μA=1.08±0.04 D. This result compares favorably to a previous measurement of μA in v′=3 and to our quantum theoretical calculations of the A 2Σ+ v′=0 state reported here.