Optimization of LANSCE Proton Beam Performance for Isotope Production

The LANSCE Isotope Production Facility (IPF) utilizes a 100-MeV proton beam with average power of 23 kW for isotope production in the fields of medicine, nuclear physics, national security, environmental science and industry. Typical tolerable fractional beam loss in the 100-MeV beamline is 4 x10-3. Experimental beam study was made to minimize the beam losses. Adjustments to the ion source extraction voltage resulted in the removal of tails in phase space. Beam based steering in beamlines led to the reduction of beam emittance growth. Readjustment of the 100-MeV quadrupole transport resulted in the elimination of excessive beam envelope oscillations and removed significant parts of the beam halo at the target. Careful beam matching in the drift tube linac (DTL) provided high beam capture (75%) in the DTL. After improvements, beam losses in the 100-MeV beamline were reduced by an order of magnitude and reached the fractional level of 5 x10-4.