Leptonic-Decay Distributions for Heavy-Lepton Pairs Produced by Colliding Beams

Abstract

We present a general differential cross section, in the colliding-beam rest frame, for $\ensuremath{\mu}e$-pair production by leptonic decays of a heavy spin-\textonehalf{} lepton pair, themselves assumed to be produced via one-quantum annihilation. Our results hold for general $V$, $A$, $S$, $T$, $P$ couplings and depend neither on the $\ensuremath{\mu}e$-universality assumption nor on the absence or presence of neutral-current effects. We also present distributions relevant to the events reported by a Lawrence Berkeley Laboratory-Stanford Linear Accelerator Center group.