• S.E. Posen, M. Liepe, N.R.A. Valles
  CLASSE, Ithaca, New York

The high magnetic and electric radio-frequency fields in superconducting microwave cavities cause heating of the inner cavity surface and generate Lorentz-forces, which deform the shape of the cavity and thereby result in a shift of the fundamental mode frequency. 3-dimensional numerical codes can create complex coupled simulations of the electromagnetic fields excited in a cavity, of heat dissipation and heat transfer, as well as of mechanical effects. In this paper we summarize our simulation results using the engineering simulation package ANSYS.

• N.R.A. Valles, M. Liepe
  CLASSE, Ithaca, New York

This paper discusses the optimization of superconducting RF cavities to be used in Cornell's Energy Recovery Linac, a next generation light source. We discuss the determination of a parameter corresponding to beam break-up current and the results of introducing a realistic higher-order-mode absorber constructed of carbon nanotubes rather than a ferrite based absorber. We conclude by comparing the threshold current of the new design and show differences are due to the new absorber material.