Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
8179075 | Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | 2013 | 12 Pages |
Abstract
We have developed a monitoring system dedicated for heavy-ion cyclotrons that incorporates lock-in amplifiers (LIAs) that can measure the beam phase of signals from phase probe with an amplitude of a few hundred nanovolts. We have compared the performance of the LIA system with that of a conventional system that incorporates oscilloscopes (OSCs). It was confirmed that the LIA system has a much higher precision than the OSC system by the measurement with a wide dynamic range of beam current. Isochronism measurements for a ring cyclotron with a low velocity gain (1.5) were made using both systems and excellent agreement was found between them. However there was a discrepancy between the beam phase measurements using the OSC system and the LIA system, for the case of a ring cyclotron with a high velocity gain of 4.0. It turned out due to a large radial variation of the phase width of circulating beam bunch according to a radial distribution of the acceleration voltage. It was also confirmed that the cable dispersion disturbs the beam-phase measurement using OSC system.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Instrumentation
Authors
R. Koyama, N. Sakamoto, M. Fujimaki, N. Fukunishi, A. Goto, M. Hemmi, M. Kase, K. Suda, T. Watanabe, K. Yamada, O. Kamigaito,