High-resolution lamb dip spectroscopy on OD and SiCl in a molecular beam

High-resolution Lamb dip spectra of OD and Si35Cl have been observed in a molecular beam. The Lamb dips of OD have a width (fwhm) of 1.5 MHz. For Si35Cl broader Lamb dips were seen; from this broadening the radiative lifetime τr=8–10 ns of individual rotational levels of the B 2Σ+, v′ =0 state was determined. The hyperfine structure of the rotational transitions could be resolved and explained by the hyperfine splitting of the ground state only