3-STEP EXCITATION OF THE 6P(3 2)NS, ND, NG AUTOIONIZING RYDBERG LEVELS VIA THE 6P6F 1/2[5/2](2) LEVEL OF LEAD/

New spectra of lead consisting of the autoionizing Rydberg energy regi on excited via the 6p6f 1/2[5/2](2) level is presented. Fifty levels a long with their FWHM widths are reported. Eleven levels of the 6p(3/2) ng (6 less than or equal to n less than or equal to 12) configuration have been reported for the first time. Besides two unassigned levels w ith effective quantum number 8.446 and 10.86, five new levels of the 6 p(3/2)9d configuration have been observed. An unexplained phenomenon i s observed where the 6pns 3/2[3/2](2) levels for n > 14 do not show up via the 6p6f (1/2)[5/2](2) route in contrast to the fact they are obs erved as strong resonances when excited via other similar routes, name ly, 6p7p 3/2[5/2](2), 6p8f 1/2[5/2](2) and 6p7f (1/2)[(5/2)](2) levels .