Dual AC Dipole Excitation for the Measurement of Magnetic Multipole Strength from Beam Position Monitor Data [electronic resource].
- Washington, D.C. : United States. Dept. of Energy. Office of Science, 2011.
Oak Ridge, Tenn. : Distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy.
- Additional Creators:
- Thomas Jefferson National Accelerator Facility (U.S.)
United States. Department of Energy. Office of Science
United States. Department of Energy. Office of Scientific and Technical Information
- An experiment was conducted at Jefferson Lab's Continuous Electron Beam Accelerator Facility to develop a technique for characterizing the nonlinear fields of the beam transport system. Two air-core dipole magnets were simultaneously driven at two different frequencies to provide a time-dependent transverse modulation of the electron beam. Fourier decomposition of beam position monitor data was then used to measure the amplitude of these frequencies at different positions along the beamline. For a purely linear transport system one expects to find solely the frequencies that were applied to the dipoles with amplitudes that depend on the phase advance of the lattice. In the presence of nonlinear fields one expects to also find harmonics of the driving frequencies that depend on the order of the nonlinearity. The technique was calibrated using one of the sextupole magnets in a CEBAF beamline and then applied to a dipole to measure the sextupole and octupole strength of the magnet. A comparison is made between the beam-based measurements, results from TOSCA and data from our Magnet Measurement Facility.
- Published through SciTech Connect.
IPAC2011, 4-9 Sep 2011, San Sebastian, Spain.
M. Spata, G.A. Krafft.
- Funding Information:
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