The hyperfine structure of the 1 ~3triangle open_g state of Na_2

摘要

The hyperfine spectra of the Na_2 1 ~3triangld open_g state have been recorded with sub-Doppler continuous wave (CW) perturbation facilitated optical-optical double resonance (PFOODR) spectroscopy via A ~1SUM_u~+～b ~3II_u mixed intermediate levels.The rotational lines into the N=14-51 levels of the 1 ~3triangld open_g state observed previously [J.Mol.Spectrosc.134,50 (1989)] have four components for transitions between symmetric rotational levels of five components for transitions between antisymmetric rotational levels and the hyperfine coupling belongs to Hund's case b_#beta#s.For the low -N levels observed later,however,the hyperfine spectra are much more complicated.We have worked out the matrix elements of the molecular Hamiltonian in the case b_#beta#s basis.After taking into consideration spin-orbit,and spin-rotation interactions,we obtained a set of molecular constants for Na_2 1 ~3triangld open_g state,with which we can reproduce the hyperfine spectra of both high-and low-N rotational levels.