Beam position measurements at Los Alamos: Isotope Production Facility and Switchyard Kicker Upgrade

The Los Alamos Neutron Science Center (LANSCE) is installing two beam lines to both improve operational tuning and provide new capabilities. The Isotope Production Facility (IFF) will provide isotopes for medical purposes by using the H⁺ beam spur at 100 MeV and the Switchyard Kicker Upgrade (SYK) will allow the LANSCE 800-MeV H^- beam to be rapidly switched between various beam lines within the facility. The beam position instrumentation for both of these beam lines uses a microstripline beam position monitor (BPM) with a 50-mm or 75-mm radius. The cable plant is unique in that it unambiguously verifies the operation of the complete position instrumentation. The processing electronics use a log ratio technique with error correction such that it has a dynamic range of -12 dBm to -85 dBm with errors less than 0.15 dB within this range. This paper will describe the primary components of these measurement systems and provide initial data of their operation.