Superconducting elliptical cavities
  We give a brief overview of the history, state of the art, and future for elliptical superconducting cavities. Principles of the cell shape optimization, criteria for multi-cell structures design, HOM damping schemes and other features are discussed along with examples of superconducting structures for various applications. 
J. K. Sekutowicz (DESY)
physics.acc-ph