Angular distributions of high-mass dileptons in high-energy hadronic collisions

Abstract

The angular distrubutions for dileptons arising from decays of a virtual photon and the $Z^0$ produced in hadronic collisions are calculated at large mass and finite transverse momentum of dileptons in the lowest order of quantum chromodynamics and the Weinberg-Salam model with three fermion generations. Numerical evaluation for coefficients of the distributions is carried out for $\overline{p}p$ collisions at $\sqrt{s}=540\mathrm{}$ GeV and $\mathrm{pp}$ at $\sqrt{s}=800\mathrm{}$ GeV in different (helicity, Gottfried-Jackson, and Collins-Soper) reference frames. Coefficients of parity-violating terms in the distributions exhibit clean signs of the $Z^0$ boson, while those of parity-conserving terms are quite insensitive to the presence of the $Z^0$ boson.