Proton-deuteron elastic scattering at small momentum transfer from 50 to 400 GeV/ c

Proton--deuteron elastic scattering has been measured in the four- momentum transfer squared region 0.013 < abs. value t < 0.14 (GeV/c)$sup 2$ and for incident proton beam momenta from 50 to 400 GeV/c. The data can be fitted with the Bethe interference formula. We observe shrinkage of the diffraction cone with increasing energy equal to (0.94 +- 0.04) ln(s/1 GeV$sup 2$) (GeV/ c)$sup -2$. This shrinkage is greater than that observed in pp elastic scattering. The ratio of the elastic to the total cross section is approximately 0.1 and independent of energy above approx. 150 GeV. In order to extract information on pn scattering we fit our data using the Glauber approach and a form factor which is the sum of exponentials. The values we obtain for the slope parameter in pn scattering are sensitive to the details of the inelastic double- scattering term. (AIP)