Sub-Doppler polarization spectroscopy of the B1Πu←X1Σg+ system for Cs2 with a titanium sapphire ring laser

Sub-Doppler ro-vibrational spectra of the B1Πu←X1Σg+ system of the Cs2 molecule have been measured in the region of 12 800-13 200 cm−1 using a polarization spectroscopic technique. A total of 18 000 lines have been assigned in 85 bands. Dunham coefficients Y00 − Y30, Y01e-Y21e, Y01f-Y21f, Y02e-Y22e, Y02f-Y22f, and Y03 − Y13 of the B state have been determined within a standard deviation of σ = 0.0016 cm−1. The RKR potential of the B1Πu state has been calculated from v′ = 0 to v′ = 12.