Negative-ion resonances and cusps in 4 1,3P electron excitation functions of the zinc atom

Negative-ion resonance structures, cusps, and possibly broad shape resonances were observed in the electron impact excitation of the 4s4p 1P1 and 4s4p 3P0,1,2 states of zinc near the thresholds of the lowest autoionizing states. Angle differential scattered electron excitation functions show strong contributions from the decay of negative-ion resonances built on a 3d excited ion core with final state spin-dependent decay. Most resonances have a 3d9ns24p2 electron configuration, and they appear in one or both of the 1P1 and 3P0,1,2 states but with different branching ratios and angular behaviors.