Measurement of proton-proton elastic scattering at 6 GeV/cin polarized initial and final spin states

The differential elastic $p-p$ scattering cross section was measured at 6 GeV/c at the Argonne Zero Gradient Synchrotron in the range $P_{\perp }^{}{}_{}{}^2=0.60\mathrm{}-1.0$ ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$ using a 65% polarized target and a 75% polarized proton beam of intensity 3 × ${10}^9$ protons/pulse. The polarization of the recoil proton was simultaneously measured with a well calibrated carbon-target polarimeter. All three polarizations were measured perpendicular to the horizontal scattering plane. Our results indicate that $P$ and $T$ invariance are both obeyed to good precision even at our largest $P_{\perp }^{}{}_{}{}^2$. Parity invariance implies that the eight single-flip transversity cross sections are zero, so our data gives the magnitudes of the eight remaining pure spin cross sections where all spins are measured. We find that the four double-flip transversity cross sections are nonzero.