Nucleon-Nucleon Polarization between 300 and 700 MeV

Abstract

The polarization parameter $P\left({\theta }^{*}\right)$ has been measured at beam energies of 310, 400, 500, 600, and 700 MeV over the range in the c.m. scattering angles $30 \mathrm{deg}<~{\theta }^{*}<~150$ deg to an accuracy of typically ±0.03 for $\mathrm{pn}$ scattering, and ±0.02 for $\mathrm{pp}$ scattering. A polarized proton beam was scattered from an unpolarized target—deuterium for quasifree $\mathrm{pn}$ and $\mathrm{pp}$ measurements, hydrogen for free $\mathrm{pp}$ measurements—and both of the outgoing nucleons from the (quasi-) elastic scatter were detected by an array of 27 scintillation counters in multichannel coincidences. It was found that $P\left({\theta }^{*}\right)$ for $\mathrm{pp}$ scattering can be approximated by $A {sin\theta }^{*} {cos\theta }^{*}$ where $A$ varies from -0.25 at 310 MeV to -0.4 at 700 MeV in this range. A comparison of $P\left({\theta }^{*}\right)$ for free and quasifree $\mathrm{pp}$ scattering reveals good agreement between the two.