Ionization beam-profile monitor at HIMAC

A prototype non-destructive beam-profile monitor employing tandem-type MCPs has been designed and tested at HIMAC. The monitor can measure the vertica l beam profile of a circulating ion beam in the synchrotron. In a series of tests, however, it was found that the monitor had a defect in the accuracy of the measured profiles. It was caused by an electric field distortion in the work area. The electric field was improved so as to create a uniform e quipotential distribution with the aid of a 3D-field simulation code. The f ield-shaping electrodes were replaced to longer ones, and the applied volta ges of each electrode were changed to the optimum values. The monitor has b een successfully used for studies of electron cooling as well as monitoring the beam under normal-mode operation in the HIMAC synchrotron. (C) 2001 El sevier Science B.V. All rights reserved.