A beam line design using a liquid PbBi target immersed in a Solenoid field to focus positrons.
A simulation will be performed to maximize positron production efficiency for a target immersed in an axial magnetic field. The simulation will use the package G4beamline developed by Muons, Inc. Unlike other beam line design packages, G4beamline will combine the physics models provided by GEANT4 for the production of electron-postiron pairs with beam transport optics to predict the emission of positrons pairs from the surface of a target inside an axial field. Prior investigations using a Tungsten target indicated an optimal thickness of 2 mm. A simulation will be used to determine this optimal thickness for the proposed target first without an axial field. The target thickness and axial magnetic field will be varied next to determine the optimal values for the preffered positron emmittance. More common beam transport packages may be employed once the emmittance of the positrons from the downstream side of the target is known.