Multiple scattering of hadrons on nuclei at large transverse momentum

This thesis consists of two theoretical explorations of double scattering in high-Pperpendicular hadron-nucleus scattering. A brief historical survey is presented. Double scattering and infrared sensitivity for nuclear targets. Single-particle and two-particle inclusive cross sections of p + A → hadrons at high Pperpendicular are studied using QCD in a multiple scattering expansion. Single-particle cross sections are shown to be infrared divergent. In contrast to this, the leading contribution to nonplanar two-particle inclusive scattering is calculated without a cutoff. The result is consistent with the available data, but a large bremsstrahlung background masks the multiple scattering signal. This background can be eliminated by studying the forward/backward asymmetry of the events in the projectile-nucleon center of mass system. This asymmetry is ∼0.1 on a W target at 800 GeV lab energy and is sensitive to the small-x structure of the target. Double scattering in nuclei and QCD. We explore the effect of double scattering on the A-dependence of high-Pperpendicular hadron-nucleus cross sections in perturbative QCD. We suggest a parametrization of inclusive high-Pperpendicular cross sections in which the effect of an additional soft scattering is expressed in terms of a single nonperturbative parameter. This parameter is related to the distribution of gluons in a bound nucleon