Study of prompt muons and associated particles in n--Be collisions. [Research in progress]

One is currently studying the associated production of prompt muons and other particles produced in n-Be collisions in the M-3 neutral beam at Fermilab. The muon arm of our two-arm spectrometer provides excellent hadron rejection and accepts particles of transverse momentum greater than 0.35 GeV/c. The muon momentum is measured with an accuracy of about +-25 percent. The precision forward arm of the spectrometer has large acceptance (x greater than 0.2) and is instrumented with equipment for lepton identification. The system is triggered whenever one or more charged particles traverse the muon arm in conjunction with at least one charged particle in the forward arm. Preliminary distributions for particles in the muon arm are presented.