Gated Microchannel Plate Photomultipliers For Longitudinal Beam Diagnostics

A gated microchannel plate photomultiplier can be used as an effective tool for measuring the longitudinal distribution of particles around most electron and high-energy proton rings. The broad available wavelength range, low noise, and high sensitivity allow using such a device for measuring the emitted synchrotron radiation and to extract the beam intensity. The fast gate rise time can be used to reject strong signals coming from filled RF buckets and avoid saturation of the photocathode so that it is possible to monitor, with a high degree of resolution, gaps in the machine fill and growth of parasitic bunches. The rugged characteristics of the device and its simplicity of use make it ideal for all those applications where more complex and expensive instrumentation is not absolutely necessary. We present the experimental results obtained at the Advanced Light Source and on the Tevatron using an Hamamatsu R5916U-50 series model