A High-resolution Diode-Based Orbit Measurement System - Prototype Results from the LHC

The pro­to­type of a high res­o­lu­tion beam po­si­tion mon­i­tor (BPM) electron­ics based on diode peak de­tec­tors was test­ed with LHC beams. In this tech­nique de­vel­oped at CERN the short beam puls­es from each BPM elec­trode are con­vert­ed into slow­ly vary­ing sig­nals by compensated diode peak de­tec­tors. The slow sig­nals can be digi­tised with a lab­o­ra­to­ry volt­meter or high res­o­lu­tion ADC. As pre­sent­ed in the paper, this tech­nique al­lows res­o­lu­tions in the order of 1 ppm of the BPM aper­ture to be achieved with a mea­sure­ment rate in the Hz range. On­go­ing de­vel­op­ments and fu­ture prospects for the tech­nique are also dis­cussed.