A high-accuracy beam current integrator for fast spin-flip experiments

Fast spin-flip experiments often require accurate beam current integration. Beam current integrators based on precision voltage-to-frequency converters are used for this purpose. As the spin-flip rate increases, fewer beam current integration pulses are counted during each spin state, resulting in unacceptably large digitization errors. A precision current integrator has been designed which operates at higher frequencies than previous devices. The design and performance of the integrator are discussed. (orig.)