An investigation of weak and electromagnetic Interactions of particles

Abstract

We have been concerned with the study of distribution functions of quarks within hadrons and the fragmentation functions of quarks, where the latter describe how a quark may fragment and, in due course of time, evolve into a shower of hadrons. A candidate for this study, we have looked at the production of charmed mesons (In particular, F - meson which is constituted by a charm quark and an antistrange quark) in hadronic collisions at high energies. Cross-sections for F-meson production from proton-proton and pion - proton collisions at high energies (20-100 GeV in the centre of mass frame) have been estimated. Considerable effort was directed at the development of a computer program to handle the multidimensional integrations involved in this computation. Initially we used the Gaussian Quadrature technique to obtain rough estimates. Finally, however, we used the recently developed technique VEGAS which does multidimensional integration utilizing the Monte Carlo technique. We studied the variation of the cross-section with different distribution functions. Our important findings are that, firstly, the F-meson production cross-section does receive a contribution from the central gluonic component though the major contribution comes from the diffractive gluonic component. Secondly, the individual contributions rise rapidly with the scattering angle, levelling off around 0-60°. Thirdly, for fixed values of the scattering angle, the cross-section is large at small transverse momenta but falls off rapidly at large values of this kinematic variable. These results could serve as tests of quantum chromodynamics. They should equally provide good checks on the analytic forms of the hadron structure functions and the quark fragmentation functions.