SIMULTANEOUS IONIZATION AND EXCITATION TO THE HE+ 2(2)P STATE

Simultaneous ionization and excitation of helium atoms by electron imp act is observed by the coincidence detection of the radiated 30.4 nm p hoton and one outgoing electron. The polarization and alignment of the 2(2)P state are determined. in the collision all three electrons chan ge state, one electron is excited to an empty orbital leaving the fina l 2p ionic state, and two electrons are in continuum final states, A p hoton decay mode is observed for the multiply excited neutral states b elow the a = 3 level oi the helium ion to the 2p ionic state. There ar e no previous coincidence observations.