Spectroscopic strength reduction of intermediate-energy single-proton removal from oxygen isotopes

Abstract

Measurements of inclusive single-proton removal cross sections from a variety of oxygen isotopes incident at intermediate energies are collected to be compared with Glauber reaction model predictions using shell-model spectroscopic factors between the initial projectile ground state and configurations of the bound core state$+$valence proton orbit. The collection of data includes a long oxygen isotopic chain spanning over $^{13--20}\mathrm{O}$ and $^{22}\mathrm{O}$ with relatively high beam energies of $305--635\phantom{\rule{0.16em}{0ex}}\mathrm{MeV}$/nucleon, which facilitates a probe into the reaction-model origin of the dependence of the spectroscopic strength reduction factor ${R}_{\mathrm{s}}$ (the ratio of the experimental over theoretical single-nucleon removal cross sections) on the binding depth $\mathrm{\ensuremath{\Delta}}S$ of the removed nucleon, as high beam energies enhance the applicability of the eikonal and sudden approximation that underlie the Glauber model. Our analysis gives ${R}_{\mathrm{s}}$ values that largely conform to the former ${R}_{\mathrm{s}}\text{\ensuremath{-}}\mathrm{\ensuremath{\Delta}}S$ systematics established upon data mainly over beam energies of $80--240\phantom{\rule{0.28em}{0ex}}\mathrm{MeV}/\mathrm{nucleon}$, yet with a slightly dampened ${R}_{s}\text{\ensuremath{-}}\mathrm{\ensuremath{\Delta}}S$ dependence, and also signs of an odd-even staggering of ${R}_{s}$ with respect to the projectile mass number $A$.