Double capture cross sections in p − Ar collisions

$p\text{\ensuremath{-}}\mathrm{Ar}$ collisions are investigated theoretically and experimentally at impact energies in the keV regime. Total cross sections for double electron capture of $p$ on Ar are calculated by an independent-particle method in the impact energy range $3\char21{}100\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$. We have measured the absolute differential and total cross sections for double electron capture for $1.0\char21{}5.0\text{\ensuremath{-}}\mathrm{keV}$ $p\text{\ensuremath{-}}\mathrm{Ar}$ collisions. The absolute differential cross section (DCS) for all the collision energies considered shows a decreasing behavior with increasing angle, exhibiting an overall decrease of three orders of magnitude. The integrated DCS is found to be between the range of $0.7\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}2}$ and $4.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}2}\phantom{\rule{0.3em}{0ex}}{\mathrm{\AA{}}}^{2}$, displays an increasing behavior as a function of the incident energy, and merges with previous data at the high-energy side. The theoretical total cross sections reproduce the structures around $5\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$ and $15\phantom{\rule{0.3em}{0ex}}\mathrm{keV}$ reported by other available measurements. The analysis of the capture into the $1{s}^{1}4{s}^{1}$ hydrogen-like configuration points in the direction of a common origin for these peaks.