Transverse Schottky and beam transfer function measurements in space charge affected coasting ion beams

Stefan Paret, Vladimir Kornilov, Oliver Boine-Frankenheim, Thomas Weiland
2010 Physical Review Special Topics. Accelerators and Beams  
A study of the transverse dynamics of coasting ion beams with moderate space charge is presented. An analytic model based on the dispersion relation with a linear space-charge force is used to describe the impact of space charge on transverse beam transfer functions (BTFs) and the stability limits of a beam. The dielectric function obtained in this way is employed to describe the transverse Schottky spectrum with linear space charge as well. The difference between space charge and impedance
more » ... e and impedance effects is highlighted. An experiment performed in the heavy ion synchrotron SIS-18 at GSI to detect space-charge effects at different beam intensities is explicated. The measured transverse Schottky spectra, BTFs and stability diagrams are compared with the analytic model. The space-charge parameters evaluated from the Schottky and BTF measurements are compared with estimations based on measured beam parameters. Furthermore, particle tracking simulations demonstrating the impact of collective effects on the Schottky and BTF diagnostics are presented. The simulation results are used to verify the space-charge model.
doi:10.1103/physrevstab.13.022802 fatcat:vkbnhkkhqren5ljswrxiud2lmq