Adjustable vibration damper design for superconducting quarter wave resonators

Detuning caused by ambient mechanical vibrations represents a significant challenge in superconducting radio frequency (SRF) cavities, particularly in low β configurations. A solution to mitigate this problem within a cryogenic environment is a frictional damper, initially developed at Laboratori Nazionali di Legnaro, Istituto Nazionale di Fisica Nucleare by A. Facco. This damper dissipates the kinetic energy of vibrations through friction. Its effectiveness is closely linked to the natural mode it aims to mitigate and the amplitude of ambient noise. Consequently, optimization is crucial for each cavity configuration. In this paper, three different optimization parameters are analyzed, and an easily configurable design of the damper is proposed. Experimental results aimed at optimizing the structural behavior of the cavity coupled with the damper are presented. Finite element analyses have been performed to model both the damping effect and the non-linear response.