LEADING ASYMMETRIES IN 2-HADRON PRODUCTION IN E(-) ANNIHILATION AT THE Z-POLE()E()

We present the leading unpolarized and single spin asymmetries in incl usive two-hadron production in electron-positron annihilation at the Z pole. The azimuthal dependence in the unpolarized differential cross section of almost back-to-back hadrons is a leading cos(2 phi) asymmet ry, which arises solely due to the intrinsic transverse momenta of the quarks. An extensive discussion on how to measure this asymmetry and the accompanying time-reversal odd fragmentation functions is given. A simple estimate indicates that the asymmetry could be of the order of a percent. (C) 1998 Elsevier Science B.V.