Method to rapidly tune the halo spoilers of the tevatron muon beam

An active shield has been constructed which forms a sharp magnetic edge around the central core of useful muons and sweeps the envelope of halo muons (those that enter the aperture of an experiment without having passed through the momentum tagging system) radially away from beam center. Two types of halo scrapers have been employed in this shield: conventional toroidal magnets and a newly developed magnetic element called ''mupipe''. The mupipes have eight degrees of motion, so attempting to tune the mupipe system by systematic measurements over the full range of each coordinate would be impractical. An algorithm was formulated to take a small set of measured values and from them predict the required positions of the two sections of mupipe to obtain maximum beam and minimum halo. The algorithm measures the muon and halo yields at a representative subset of coordinated, employs a fitting program to find a functional form for the yields in terms of the coorinated, and maximizes that function in terms of the coordinates. The algorithm was tested by applying a Monte Carlo program to predict the halo and muon yield for a given orientation of the two movable sections of mupipe