DEVELOPMENT OF AN ADAPTIVE MASKING METHOD TO IMAGE BEAM HALO

Title of Document: DEVELOPMENT OF AN ADAPTIVE MASKING METHOD TO IMAGE BEAM HALO Hao Zhang, Master of Science, 2011 Directed By: Professor Patrick G. O‟Shea Department of Electrical and Computer Engineering Dr. Ralph B. Fiorito and Professor Rami A. Kishek Institute for Research in Electronics and Applied Physics Beam halo is a common phenomenon in most intense particle beams and is associate with many bad effects. Halo is very hard to characterize because of its low intensity, which requires a measurement system with high dynamic range (≥10 5 ). Here, we have developed a technique that employs a digital micro-mirror array to produce an image of the halo of an electron beam with an enhanced dynamic range. Light produced by the beam intercepting a phosphor screen is first imaged onto the array; an adaptive mask is created and applied to filter out the beam core; and the result is reimaged onto an CCD camera. In this thesis, we describe the optics used, the masking operation and preliminary results of experiments we have performed to study beam halo at the University of Maryland Electron Ring. DEVELOPMENT OF AN ADAPTIVE MASKING METHOD TO IMAGE BEAM HALO

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