Long Radiation Detector System for Beam Loss Monitoring

This paper describes the Long Radiation Monitor (LRM) system installed at the 200 MeV linac at Brookhaven National Laboratory. This system allows observation of both the spatial and temporal character of the losses in the linac and its transport lines. An array of large diameter gas filled coaxial cables are used as extended ion chambers to detect the losses. The output signals are available as a histogram, video waveforms, and numerical data via the computer. A fast beam interrupt is also provided. The detector characteristics and details of the processing electronics are presented. Results of studies of longitudinal, steering and focusing losses are described.