Atomic-electron capture in the presence of a narrow nuclear resonance: 40Ar(p,p)40Ar reaction.

Abstract

Electron capture in close, energetic collisions between protons and Ar atoms is studied. As the proton energy is varied across the 1859.7-keV $^{40}\mathrm{Ar}$(p,p${)}^{40}$Ar elastic nuclear resonance at a fixed deflection angle of 60\ifmmode^\circ\else\textdegree\fi{}, a dip of about 27% in the atomic-electron-capture probability is found, demonstrating the influence of the nuclear process on the atomic-charge exchange. The effect is very large considering that the similar dip found in the probability for scattering the proton without capture is only about 37%. A systematic comparison with previously reported capture probabilities for other elastic reactions has been made.