The proton and deuteron analyzing powers and ten of the possible 12 spin correlation coefficients have been measured for p+d elastic scattering at proton bombarding energies of 135 and 200 MeV. The results are compared with Faddeev calculations using two different NN potentials. The qualitative features of the extensive data set on the spin dependence in p+d elastic scattering over a wide range of angles presented here are remarkably well explained by two-nucleon force predictions without inclusion of a three-nucleon force. The remaining discrepancies are, in general, not alleviated when theoretical three-nucleon forces are included in the calculations.

We have measured three axial polarization observables in d-->p--> breakup with a polarized 270 MeV deuteron beam on a polarized proton target. Axial observables are zero by parity conservation in elastic scattering but can be easily observed in the breakup channel at the present energy. Based on a symmetry argument, the sensitivity of these observables to the three-nucleon force might be enhanced. Calculations without three-nucleon force are in fair agreement with our measurement, indicating that the expected sensitivity of axial observables to the three-nucleon force is not confirmed. Including a three-nucleon force in the calculation does not improve the agreement with the data.

We have measured three axial polarization observables in (d) over right arrow(p) over right arrow breakup with a polarized 270 MeV deuteron beam on a polarized proton target. Axial observables are zero by parity conservation in elastic scattering but can be easily observed in the breakup channel at the present energy. Based on a symmetry argument, the sensitivity of these observables to the three-nucleon force might be enhanced. Calculations without three-nucleon force are in fair agreement with our measurement, indicating that the expected sensitivity of axial observables to the three-nucleon force is not confirmed. Including a three-nucleon force in the calculation does not improve the agreement with the data.

A first measurement of longitudinell as well as transverse spin correlation coefficients for the reaction pp->pn pi+ is made using a polarized proton target and a polarized proton beam. We repor ...

In a kinematically complete experiment we have measured the two analyzing powers and the five spin correlation coefficients of the reaction (pol)p pol(p) -> p p pi0 as a function of all five par ...

In a kinematically complete experiment we have measured the two analyzing powers and the five spin correlation coefficients of the reaction $\stackrel{\ensuremath{\rightarrow}}{p}\stackrel{\ensuremath{\rightarrow}}{p}\ensuremath{\rightarrow}\mathrm{pp}{\ensuremath{\pi}}^{0}$ as a function of all five parameters of the three-body final state for bombarding energies between 325 and 400 MeV. The data are in disagreement with the theoretical predictions available at this time. Below 400 MeV, fewer than a dozen complex partial-wave amplitudes are likely to be significant, and it is expected that the present experimental information constrains these amplitudes. We also describe the formalism for an expansion of the spin observables into a complete set of angular functions and use this to completely characterize the polarization information obtainable from reactions with polarized spin-1/2 collision partners and a three-body final state.

The spin correlation coefficent combinations A(xx)+A(yy) and A(xx)-A(yy), the spin correlation coefficients A(yz) and A(zz), and the analyzing power were measured for (p) over right arrow (p) over right arrow-->d pi(+) between center-of-mass angles 25 degrees less than or equal to theta less than or equal to 65 degrees at beam energies of 350.5, 375.0, and 400.0 MeV. The experiment was carried out with a polarized internal target and a stored, polarized beam. Nonvertical beam polarization needed for the measurement of A(zz) was obtained by the use of solenoidal spin rotators. Near threshold, only a few partial waves contribute, and pion s and p waves dominate with a possible small admixture of d waves. Certain combinations of the observables reported here are a direct measure of these d waves. The d-wave contributions are found to be negligible even at 400.0 MeV.

The PINTEX facility at the IUCF Cooler ring, dedicated to the study of spin dependence in nucleon-nucleon interactions, has been used to measure polarization observables of the reaction pp -> pp pi0 at beam energies between 325 and 400 MeV. The stored polarized proton beam had spin projections both in the longitudinal and the transverse directions with respect to the beam momentum. We report here on the measurements of the relative transverse and longitudinal spin-dependent cross sections, deltasigma_T/sigma_tot and deltasigma_L/sigma_tot, and how from these observables the initial spin singlet and triplet cross sections are obtained. Considering angular momentum states less or equal to one, the contribution of the Ps partial waves to the cross section can be extracted.

The spin correlation coefficent combinations ${A}_{\mathrm{xx}}{+A}_{\mathrm{yy}}$ and ${A}_{\mathrm{xx}}\ensuremath{-}{A}_{\mathrm{yy}},$ the spin correlation coefficients ${A}_{\mathrm{xz}}$ and ${A}_{\mathrm{zz}},$ and the analyzing power were measured for $\stackrel{\ensuremath{\rightarrow}}{p}\stackrel{\ensuremath{\rightarrow}}{p}\ensuremath{\rightarrow}d{\ensuremath{\pi}}^{+}$ between center-of-mass angles $25\ifmmode^\circ\else\textdegree\fi{}<~\ensuremath{\theta}<~65\ifmmode^\circ\else\textdegree\fi{}$ at beam energies of 350.5, 375.0, and $400.0 \mathrm{MeV}.$ The experiment was carried out with a polarized internal target and a stored, polarized beam. Nonvertical beam polarization needed for the measurement of ${A}_{\mathrm{zz}}$ was obtained by the use of solenoidal spin rotators. Near threshold, only a few partial waves contribute, and pion $s$ and $p$ waves dominate with a possible small admixture of $d$ waves. Certain combinations of the observables reported here are a direct measure of these $d$ waves. The $d\ensuremath{-}\mathrm{wave}$ contributions are found to be negligible even at $400.0 \mathrm{MeV}.$

We report a measurement of the spin-dependent total cross section ratios delta_sigma_T/sigma_tot and delta_sigma_L/sigma_tot of the pp –> pp pi^0 reaction between 325 MeV and 400 MeV. The experiment was carried out with a polarized internal target in a storage ring. Non-vertical beam polarization was obtained by the use of solenoidal spin rotators. Near threshold, the knowledge of both spin-dependent total cross sections is sufficient to deduce the strength of certain participating partial waves, free of any model.