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Power, J.

Publications and source records attributed to Power, J..

A rotor-based multileaf collimator for beam shaping

We introduce a new style of multileaf collimator which employs rotors with angularly dependent radius to control the masking aperture: a rotor-based multileaf collimator (RMLC). Using a padlock-inspired mechanism, a single motor can set dozens of rotors, i.e. leaves, independently. This is especially important for an ultra-high vacuum (UHV) compatible MLC, since this reduces the number of actuators and vacuum feedthroughs required by more than an order of magnitude. This new RMLC will complement previous work employing a UHV compatible MLC with an emittance exchange beamline to create arbitrarily shaped beams on demand. A feed-forward control system which abstracts away the complexity of the RMLC operation, and is adaptable to real beamline conditions, is discussed and demonstrated in simulation.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND

Second Order Angle of Incidence Corrections for GaAs /Ge Solar cells with Low Absorptance Coverglass

The objective of this paper was to determine any angle of incidence effects beyond the cosine and Fresnel reflection corrections. Two samples each of several GaAs /Ge cell assemblies were measured at incidence angles from 0 to 85o to provide a survey for possible second order corrections that would have to be applied to solar arrays with non-normal incident light.

angle of incidence effects