ANALYSIS AND TRANSITION-PROBABILITIES FOR THE NA-2 B-1-PI(U)-]X-1-SIGMA(-ANGSTROM AR+ LASER LINE()(G) SYSTEM USING AN EXCITATION THE 4727)

The fluorescence spectrum of Na-2 induced by the 4726.87 Angstrom line of an Argon ion laser has been analyzed with special emphasis on dete rmination of accurate relative intensities. This work extends previous observations on Na-2 by using this excitation line. We have observed eight fluorescence series for the B(1)Pi(u) --> X(1)Sigma(g)(+) band s ystem corresponding to the excitation transitions upsilon' = 9, J' = 3 8 <-- upsilon '' = 1, J '' = 37; upsilon' = 14, J' = 46 <-- upsilon '' = 4, J '' = 47; upsilon' = 14, J' = 81 <-- upsilon '' = 3, J '' = 80; upsilon' = 15, J' = 65 <-- upsilon '' = 4, J '' = 66; upsilon' = 12, J' = 36 <-- upsilon '' = 3, J '' = 36; upsilon' = 12, J' = 40 <-- upsi lon '' = 3, J '' = 39 upsilon' = 17, J' = 45 <-- upsilon '' = 6, J' = 45 and upsilon' = 18, J' = 63 <-- upsilon '' = 6, J '' = 63. The seven latter series are reported for the first time. Optically pumped laser transitions obtained in Na-2 vapor by using this excitation wavelengt h have been assigned. The radiative transition probabilities for the o bserved fluorescence series were calculated using hybrid potential ene rgy curves for the B(1)Pi(u) and X(1)Sigma(g)(+) states constructed up to last vibrational levels and an nb initio transition dipole moment function. Radiative lifetimes for the rovibrational levels of the uppe r states pumped by the laser line have also been calculated. The trans ition probabilities and lifetimes agree with the corresponding observe d measurements, usually within the experimental uncertainty. From the rotational satellite structure with Delta J' = +/-1 and +/-2 of some b ands, for the most intense fluorescence series, collision-induced tran sition rates and average cross sections have been obtained. (C) 1998 A cademic Press.