The 2 3Πg←x 3Σu triplet system of Cs2

The triplet system 2 3-PI-g <-- x 3-SIGMA-u of the Cs2 molecule around 710 nm was investigated using laser-induced fluorescence and resonant two-photon ionization in a collimated supersonic cold argon beam seeded with cesium. The analysis of the spectra yields the fine-structure splittings and the vibrational spacings of the 3-PI-g state and the vibrational spacings of the x 3-SIGMA-u state. A comparison with pseudo-potential calculations is presented.