M. Acciarri et al., MEASUREMENT OF MUON-PAIR PRODUCTION AT 50GEV-LESS-THAN-ROOT-S-LESS-THAN-86GEV AT LEP, Physics letters. Section B, 374(4), 1996, pp. 331-340
Using the data recorded with the L3 detector at LEP, we study the proc
ess e(+)e(-) --> mu(+)mu(-)(gamma) for events with hard initial-slate
photon radiation. The effective centre-of-mass energies of the muons r
ange from 50 GeV to 86 GeV. The data sample corresponds to an integrat
ed luminosity of 103.5 pb(-1) and yields 293 muon-pair events with a h
ard photon along the beam direction. The events are used to determine
the cross sections and the forward-backward charge asymmetries at cent
re-of-mass energies below the Z resonance.