Comparison of the Techniques for Multipactor Discharge Damping in Coupling Cells of CDS Accelerating Structure

In the CDS structure proposed to substitute the first cavity of the main part of the linac at the Institute for Nuclear Research of the Russian Academy of Sciences, the appearance of a multipactor discharge (MP) in coupling cells at the operating level of the accelerating field was detected. Earlier, an option for MP damping by alternating neighbor accelerating cell frequency detuning was considered. This option complicates the cavity section tuning. An option for MP removal by changes in the coupling cell geometry inducing the destruction of phase conditions of the electron cloud resonance motion was studied. The analytical estimation and results of numerical simulations are presented. In conditions of the first cavity of the INR linac, the options considered were compared with respect to the efficiency of MP damping and the enhanced resistivity to the increase of the secondary emission yield.