Quark elastic scattering in gauge theories and large-transverse-momentum hadron production

Abstract

Quark elastic scattering in a color gauge theory of quarks and gluons is investigated as a source of large-transverse-momentum hadrons. Nonscaling effects due to asymptotic freedom alone are not helpful in describing the data. Elastic quark-quark form factors derived in color gauge theories do describe the data if supplemented by a phenomenological assumption which probably amounts to antiscreening of the color of quarks in a proton. Transverse-momentum fluctuations of quarks in protons are quite important for understanding the normalization and shape of the theory. Patterns of scaling violations are predicted which may be compared with good future data to test the models.