Multiple electron emisión from noble gases colliding with proton beams, including post-collisional effects

M.E. GALASSI; R. RIVAROLA; P.D. FAINSTEIN

PHYSICAL REVIEW A - ATOMIC, MOLECULAR AND OPTICAL PHYSICS

AMER PHYSICAL SOC

Año: 2007 vol. 75 p. 1 - 7

1050-2947

The process of multiple electron ionization of Ne andAr noble gases produced by impact of proton beams is studied inthe framework of the Independent Electron Model (IEM). The roleplayed by different mechanisms is analyzed, including inter-shellAuger and intra-shell Coster-Kronig electron emission which followthe production of vacancies due to direct interaction of theprojectile with the target electrons. Present results, obtainedwith the continuum distorted wave-eikonal initial stateapproximation (CDW-EIS), confirm previous predictions given by adifferent theoretical model. Semi-empirical approximations areintroduced by using analytical single-ionization probabilitieswith adjustable parameters determined from CDW-EIS total crosssections. The low-consuming computational time required tocalculate multiple ionization cross sections with thesesemi-empirical approximations and the good agreement found withexisting experimental data and with results obtained with moreelaborated theoretical models make of them good candidates tostudy electron emission from complex targets.