Total cross sections of K± and p¯ on hydrogen and deuterium were measured in a standard transmission experiment with statistical precisions of the order of 0.05-0.25%. Data were obtained in the momentum range 2.45-3.30 GeV/c for K−N, 1.55-3.30 GeV/c for K+N, and 1.00-3.30 GeV/c for p¯N. Cross sections for the pure isotopic spin states are obtained using a procedure for the deuterium data which takes into account Fermi motion and the shadow effect. Evidence for the following new structures was found: Y1*(2455), Y1*(2620), Y0*(2585), Z1*(2150), Z1*(2500), π1*(2290), π1*(2350), and π0*(2375).
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The first direct measurements of neutron-proton and neutron-deuteron total cross sections in the momentum range 14 to 27 GeV/c are presented. The np total cross section apparently becomes less than the pp total cross section in this momentum region. Our results show no evidence for a rapid vanishing of the Glauber screening correction as predicted by Abers et al. on the basis of Regge theory.
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NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document. The cross section for photoproduction of neutral pions from protons has been measured at energies near 750, 915 and 1150 Mev and over most of the forward-going [...] C.M. hemisphere. The experimental technique consisted of detecting both of the [...] decay photons with lead glass total absorption counters and, when convenient, the recoil proton with a single scintillation counter. The method is subject to rather large systematic errors but, within these, our results are consistent with other experiments wherever there are overlapping points. Our data has the striking feature that the cross section is very small at [...] in the region of the second and third pion nucleon resonances. Also, although the data is not inconsistent with a simple first, second and third resonance model, it appears likely that above the third resonance the pole process consisting of the exchange of a single vector meson is becoming important or even dominant. The evidence at this time mildly suggests that this behaviour is largely due to [...] mesons and under that hypothesis we are able to estimate some [...] meson coupling constants. For example, using a prescription of Gell-Mann and Zachariasen, we estimate the partial width for the decay [...] to be 240 Kev.
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Total (π+, p) and (p, p) cross sections in the momentum range 1.4 to 4.0 Bev/c are presented. These measurements, with an accuracy of approximately 2%, were made at the Berkeley Bevatron by using counter techniques. Pions were distinguished from protons by means of a gas-filled Čerenkov counter. The (π+, p) total cross section was found to be almost constant above 2.0 Bev/c at a value near 29 mb. The (p, p) cross section decreases gradually from 47.5 mb to 41.7 mb over the momentum range covered. Transmission measurements of π+-nucleus and p-nucleus cross sections in both good and poor geometry were made at 3.0 Bev/c. The results are compared with the predictions of the optical model. In contrast to most previous work at high energies, an essentially exact solution of the wave equation for a potential well with a diffuse edge was used. The values of the imaginary part of the optical potential that best fit the experimental data are in good agreement with the predicted values. No strong conclusion regarding the real part of the potential was possible. Absorption and total elastic scattering cross sections for Be, C, Al, and Cu are presented. The total elastic scattering cross sections from this experiment disagree with Wikner's for π−-nucleus scattering.
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