W. H. Dragoset

Measurement of the transverse spin dependence of the pp total cross section in the 1–3 GeV/c region☆

Abstract The pp total cross section difference between pure transverse spin states was measured in the laboratory momentum range 1–3 GeV/ c . Significant differences were found and these differences show striking energy dependence. This structure is in disagreement with the predictions of simple exchange models.

Measurement of the spin parameters A and Ann in pp elastic scattering in the 1–3 GeV/c region☆

Abstract We have measured the asymmetry parameter A and the spin correlation parameter A nn in pp elastic scattering, using the Argonne ZGS polarized proton beam and a polarized proton target. Angular distributions of A and A nn for | t | ≳ 0.2 (GeV/ c ) 2 were obtained at eight momenta between 1.10 and 2 if 2.75 GeV/ c . We find significant structure in both the energy and t -dependence of A nn at these energies. At p lab ≈ 1.34 GeV/ c A nn reaches a very large value of about 0.8–0.9 near θ cm = 90°.

Reaction mechanisms and isospin effects for the π±+D→p+π±+n processes at Pπ=340 MeV/c

Abstract The first kinematically complete counter measurements of the D( π ± , pπ ± )n reactions in the Δ(1232) region are reported. Calculations based on low order diagrams compare well with the data. The ratio pπ + /pπ − depends strongly on the spectator particle momentum, and its behavior is qualitatively reproduced.

Energy dependence of Ann(90°) in pp elastic scattering from 1.10 to 2.75 GeV/c

We have measured the spin correlation parameter Ann in pp elastic scattering near ΘCM=90° from 1.10 to 2.75 GeV/c. We find that Ann(90°) has a pronounced peak at Plab≂1.34 GeV/c, reaching a value of about 0.8–0.9.

Transverse spin dependence of pp total cross‐sections

A brief report is given of some preliminary results from an experiment in progress on the measurement of the difference between pp total cross sections in pure initial spin states transverse to the beam direction for incident momenta of 1 to 3 GeV /c in the laboratory. Two preliminary data points are plotted. (JFP)

Pion production on Li6 via the reaction 6Li(p,dπ+)He5 at Ep=800 MeV

The external proton beam of the Los Alamos Meson Physics Facility (LAMPF) was used to study π+ and π− production on light elements at 800 MeV incident proton energy. Although the Li6 nucleus is not the simplest nucleus to test various reaction mechanisms for pion production, the fact that it can be well represented by a two‐body system such as d‐He4, makes it possible to apply a similar general approach for study of three‐body nuclear reactions as in the case of pion production on hydrogen and deuterium.1,2

Pion production in p‐p interactions at 800 MeV

The production of pions in p‐p interactions was recently measured in a kinematically‐complete counter experiment at 800 MeV. Kinematic conditions were chosen to examine in detail several pion production mechanisms.

Pion production by 800 MeV protons from deuterium with a spectator neutron

Pion production induced by 800 MeV protons on deuterium has been investigated under conditions where the neutron in the deuteron target remains a spectator to the reaction. The cross section for this process is large and accounts for a large fraction of the total pion production in this kinematic region.