||Strongly HOM-damped single-cell
cavities have been used for some time in storage rings where modest
voltage and high beam current are required. Future high-current
applications such as electron cooling or high-powered free electron
lasers based on energy-recovered linacs would benefit from similarly
damped multi-cell structures. We explore the possibilities for applying
strong HOM damping techniques to multi-cell structures. We use modern
simulation techniques to compare several commonly used methods such as
beam-pipe damping, coaxial and waveguide dampers, and the influence of
number of cells and cell shape on the resulting impedance.
(Superstructures consisting of more than one multi-cell cavity are not
covered here but are discussed elsewhere at this meeting). We also
consider the possibilities for even stronger damping, if required, and
discuss the implications for cavity construction and performance that
might result from these changes.