We have made measurements of polarization in π−p elastic scattering, with emphasis over the backward region, at 1.60 to 2.28 GeVc. The results indicate the absence of u-channel dominance in the backward region, as was observed in the case of π+p scattering. Comparisons have been made with predictions of various phase-shift analyses which show that the agreement is generally very poor in the backward region.
The polarization parameter for K + p elastic scattering has been measured at 1.60, 1.80, 2.11 and 3.31 GeV/ c incident momenta over the entire angular range with an emphasis on the backward region. The results in the extreme backward region appear to be small and consistent with zero.
The polarization parameter P(t) for the reaction π−p→π0n has been measured at 3.5 and 5.0 GeV/c over the range 0.2<~−t<~1.8 (GeV/c)2. The two γ rays from the π0 decay were detected in a large lead-glass hodoscope. The results agree with the positive polarization values found in earlier Argonne National Laboratory data at −t<0.35 (GeV/c)2. P(t) drops to a small value near t=−0.6 (GeV/c)2 and remains the same out to t=−1.8 (GeV/c)2.
Full angular distributions of the polarization parameter in elastic K+p scattering at 1.37, 1.45, 1.60, 1.71, 1.80, 1.89, 2.11, and 2.31 GeV/c are presented. These data were obtained in an experiment at the Zero Gradient Synchrotron using a polarized proton target with arrays of scintillation and Čerenkov counters to detect the scattered particles.
We report measurements of the polarization parameters in π+p and π−p elastic scattering at an incident momentum of 100 GeV/c. The results cover the range 0.18<~−t<~1.4 GeV2 and are in agreement with current Regge-model predictions.
Measurements of the polarization parameters and angular distributions are reported for π±p elastic scattering at 100 GeV/c and for pp elastic scattering at 100- and 300-GeV/c incident momentum. The π±p data cover the kinematic range 0.18≤−t≤1.10 GeV2 and are in agreement with current Regge-model predictions. The pp data cover the kinematic range 0.15≤−t≤1.10 GeV2 and 0.15≤−t≤2.00 GeV2 at 100 and 300 GeV/c, respectively, and are found to be consistent with absorption-model predictions.
Measurements of polarization in π+p elastic scattering have been made at 1.60, 1.80, 2.11, and 2.31 GeVc. The data cover the entire angular range, with emphasis on the backward region. Comparisons have been made with both u-channel and t-channel models, as well as with predictions of phase-shift analyses. While the agreement is generally poor in all cases, the best agreement is with some t-channel predictions.
From measurements of proton-proton elastic scattering at very small momentum transfers where the nuclear and Coulomb amplitudes interfere, we have deduced values of ρ, the ratio of the real to the imaginary forward nuclear amplitude, for energies from 50 to 400 GeV. We find that ρ increases from -0.157 ± 0.012 at 51.5 GeV to +0.039 ± 0.012 at 393 GeV, crossing zero at 280 ± 60 GeV.
Measurements of the cross section for the reaction p+p→π0+anything have been completed. The data cover a range of incident proton energies 50-400 GeV, π0 transverse momenta 0.3-4 GeV/c, and laboratory angles 30-275 mrad. The experiment was performed using the internal proton beam at the Fermi National Accelerator Laboratory. A lead-glass counter was used to detect photons from the decay of π0's produced by collisions in thin targets of hydrogen or carbon. Tables of the measured cross sections are presented.
Measurements of the energy and t dependence of diffractive Jψ photoproduction are presented. A significant rise in the cross section over the energy range 60-300 GeV is observed. It is found that (30±4)% of the events are inelastic.
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