A resonant beam detector for Tevatron tune monitoring

An inductively resonated balanced stripline pickup has been constructed for observing tune spectra. The device is a sensitive betatron oscillation and Schottky noise pickup, providing a 25-dB gain over untuned detectors of like geometry. The electrodes are motorized, allowing remote adjustment of the device center and aperture. To tune the resonator onto the 21.4-MHz operating frequency, a motorized capacitor is employed. Quadrature signals from a pair of detectors have enabled observation of individual proton and antiproton coherent motions to nanometer levels. >