Elastic scattering data was successfully taken using the new "Clamshell" spectrometer. Angular distributions of elastic differential cross sections were obtained at 50 MeV and 65 MeV using positive and negative pions scattered from ⁵⁶Ni, ⁶⁰Ni, and ⁶⁴Ni. The data were compared to predictions made using the MSU optical potential, The π⁺ data agreed fairly well with the predictions at both 50 MeV and 65 MeV while the corresponding π⁻ data significantly disagreed with the predictions. The absorption parameters in the MSU potential were varied in an attempt to fit the data. A suitable fit was achieved for both π⁺ and π⁻ data at 50 MeV and 65 MeV. The real part of the p-wave absorption parameter was well determined but showed two distinct values for π⁺ and π⁻ indicating that there is a separate potential for π⁺ and π⁻ or that the absorption part of the potential is inadequately formulated. / Ph. D.

Measurements of the differential cross sections for backward (pi)('+)p and (pi)('-)p elastic scattering have been made for incident pion momenta between 30 and 90 GeV/c in the angular range 0 ) p(pi)('-), the (DELTA)(,(delta)) and N(,(alpha)) for (pi)('+)p (--->) p(pi)('+). As is given by this model, the momentum dependence of the differential cross-section, d(sigma)/du for fixed u, may be parameterized with the form (DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI) The values n('+) = 2.31 (+OR-) 0.07 and n('-) = 2.08 (+OR-) 0.06 are obtained for n at u = 0 for (pi)('+) and (pi)('-) scattering respectively.

Measurements of the differential cross-section for elastic scattering of positive and negative kaons off of a proton target are given in this dissertation. The beam momenta were 100 GeV/c and 200 GeV/c. The range of t, the four momentum transfer squared, measured was 0.4 < -t < 3.0. The experiment was performed at Fermilab. The data is consistent with previous experiments. Because of the much greater statistical accuracy of this experiment, it is now clear that the apparent equality of the pion and kaon cross-sections at larger t was due to poor statistical accuracy. The experimental results are not predicted by any theory. Furthermore, the difference between the pion and kaon differential cross-sections is not explained by geometrical scaling, as it was in the past.