Beam Characterization in CEBAF-ER

Energy recovering a 1 GeV beam through CEBAF (Continuous Electron Beam Accelerator Facility) presents many operational challenges. As a result, it is important to have a quantitative understanding of the beam behavior throughout the machine. The emittance provides a figure of merit in this context inasmuch as it characterizes the extent to which beam quality is preserved during energy recovery. A solution to the problem of obtaining a high-resolution emittance measurement in the extraction region of the CEBAF-ER experiment (CEBAF with Energy Recovery) is presented. The method makes use of a single scanning quadrupole and a downstream wire scanner. In addition, by using multiple wire scans, a scheme for measuring the emittance and momentum spread of the first pass beam in the injector and Arcs 1 and 2 was implemented. And by using a novel technique employing wire scans in conjunction with PMTs (Photomultiplier Tubes) to accurately measure the beam profile at the dump, we can quantify . ..