Forward-angle elastic and quasielastic proton-nucleon cross sections and analyzing powers at 0.8 GeV

Abstract

Using a liquid deuterium target, 800 MeV quasielastic $\stackrel{\ensuremath{\rightarrow}}{p}+n$ and $\stackrel{\ensuremath{\rightarrow}}{p}+p$ analyzing powers were measured over the center-of-momentum angular range 14\ifmmode^\circ\else\textdegree\fi{}-75\ifmmode^\circ\else\textdegree\fi{}. Elastic $\stackrel{\ensuremath{\rightarrow}}{p}+p$ analyzing powers were measured over the center-of-momentum angular range 10\ifmmode^\circ\else\textdegree\fi{}-47\ifmmode^\circ\else\textdegree\fi{} using a liquid hydrogen target, and elastic $p+p$ differential cross sections were obtained over the angular range 6\ifmmode^\circ\else\textdegree\fi{}-90\ifmmode^\circ\else\textdegree\fi{} using CH and C${\mathrm{H}}_{2}$ targets. The quasielastic $\stackrel{\ensuremath{\rightarrow}}{p}+p$ data are in good agreement with existing elastic $\stackrel{\ensuremath{\rightarrow}}{p}+p$ data, suggesting that the effects of final state interactions and Fermi motion averaging are small at this energy for the range of momentum transfer covered by these data. Results of phase shift analyses are reported, and the amplitudes important to microscopic analysis of 800 MeV $\stackrel{\ensuremath{\rightarrow}}{p}$+nucleus elastic differential cross section and analyzing power data are discussed. Use of these amplitudes to generate the microscopic Kerman-McManus-Thaler optical potential for 800 MeV $\stackrel{\ensuremath{\rightarrow}}{p}$+$^{40}\mathrm{Ca}$ elastic scattering does not resolve the problems encountered previously concerning nuclear size information and poor fits to the analyzing power data.NUCLEAR REACTIONS $^{2}\mathrm{H}(\stackrel{\ensuremath{\rightarrow}}{p}, pn)p$, $^{2}\mathrm{H}(\stackrel{\ensuremath{\rightarrow}}{p}, pp)n$, $^{1}\mathrm{H}(\stackrel{\ensuremath{\rightarrow}}{p}, p)$, $^{1}\mathrm{H}(p, p)$; ${E}_{p,\mathrm{inc}}=800$ MeV; measured $p+p$ elastic $\frac{d\ensuremath{\sigma}}{d\ensuremath{\Omega}}$ for $6\ifmmode^\circ\else\textdegree\fi{}\ensuremath{\le}{\ensuremath{\theta}}_{\mathrm{c}.\mathrm{m}.}\ensuremath{\le}90\ifmmode^\circ\else\textdegree\fi{}$; measured $\stackrel{\ensuremath{\rightarrow}}{p}+p$ elastic ${A}_{y}(\ensuremath{\theta})$ for $10\ifmmode^\circ\else\textdegree\fi{}\ensuremath{\le}{\ensuremath{\theta}}_{\mathrm{c}.\mathrm{m}}\ensuremath{\le}47\ifmmode^\circ\else\textdegree\fi{}$; measured $\stackrel{\ensuremath{\rightarrow}}{p}+p$ and $\stackrel{\ensuremath{\rightarrow}}{p}+n$ quasielastic ${A}_{y}(\ensuremath{\theta})$ for $14\ifmmode^\circ\else\textdegree\fi{}\ensuremath{\le}{\ensuremath{\theta}}_{\mathrm{c}.\mathrm{m}.}\ensuremath{\le}75\ifmmode^\circ\else\textdegree\fi{}$; CH, C${\mathrm{H}}_{2}$, liquid hydrogen and liquid deuterium targets; two arm coincidence for quasielastic; phase shift analyses; microscopic (KMT) optical model calculations for 800 MeV $\stackrel{\ensuremath{\rightarrow}}{p}$+$^{40}\mathrm{Ca}$.