Electron impact excitation of the ( ... 6s6p P-3(J)) levels in ytterbium

Differential cross sections (DCS) and electron impact coherence parame ters (EICP) have been measured and calculated for the (...6s6p P-3(J)) levels i n ytterbium. DCS for the (...6s6p P-3(1))and (...6s6p P-3(2)) levels were d etermined at collision energies of 10, 20 and 40 eV. EICP for the (.,.6s6p P-3(1)) intermediate-coupled level were determined at collision energies of 20 and 40 eV. Calculations were made in the unitarized distorted-wave appr oximation. Measurements were made in a crossed-beam apparatus with EICP mea sured using the technique of superelastic scattering from atoms laser-excit ed into the P-3(1) level.