Differential Cross Sections for Electron Capture from Argon by 6-MeV Protons

Abstract

Differential cross sections for the capture of electrons from argon by 6-MeV protons have been measured as a function of the hydrogen-atom scattering angle between 0.02\ifmmode^\circ\else\textdegree\fi{} and 0.14\ifmmode^\circ\else\textdegree\fi{}. Cross sections were measured for capture from all shells and from the argon $K$ shell alone. The differential cross section for $K$-shell capture does not agree with theoretical results obtained using either the Oppenheimer-Brinkman-Kramers approximation or a Born calculation which includes a contribution from the core-core interaction.