Study of Higher Order Modes in Multi-Cell Cavities for BESSY-VSR Upgrade

Tomasz Galek, Korinna Brackebusch, Shahnam Gorgi Zadeh, Ursula Van Rienen, Petit-Jean-Genaz, Christine (Ed.), Arduini, Gianluigi (Ed.), Michel, Peter (Ed.), Schaa, Volker RW (Ed.)
BESSY-VSR is a planned scheme to upgrade the existing BESSY II storage ring to support variable electron pulse lengths. In addition to the present 0.5 GHz energy replenishment cavity, two additional SRF bunch compressing cavities operating at 1.5 GHz (3rd harmonic) and 1.75 GHz (sub-harmonic), will be installed. These cavities are essential to produce short 1.5 ps bunches with current of up to 0.8 mA per bunch. In order to achieve such high beam currents, higher order modes must be damped in
more » ... superconducting cavities. In this work we present analysis of higher order modes in cavities with different mid-cell shapes.
doi:10.18429/jacow-ipac2014-mopme017 fatcat:2w7qhoqu2zdvhf4drb72z2lpbe