PHOTOIONIZATION OF THE 6P2 (LS)J STATE IN BARIUM - MEASUREMENT AND CALCULATION OF THE PARTIAL CROSS-SECTIONS

We report partial photoionization cross sections of the 6p2 P-3(0), and 6p2 P-3(1) states of barium in the continuum range 59 500-63 400 cm-1 close to the 6p1/2.3/2 thresholds. For a fixed geometry of the laser excitation, and fixed solid angle of detection, photoelectrons are measured in the 6s1/2e (p) and 5d3/2.5/2e(p) continua. We focus on the 6p2 P-3(1) case, for which we use R-matrix method in combination with the multichannel quantum defect theory to compute the partial cross sections. Comparison with experiment is satisfactory and leads to the identification of new 6p3/2 nd; J = 1, 6p1/2.3/2 nd; J = 2 and 6p3/2ns; J = 1 series.