Eigenmodes of superconducting cavities calculated on an APE-100 supercomputer (SIMD)

The construction of modern accelerators is usually supported by the numerical determination of eigenmodes in the accelerating cavities. Often the rotational symmetry of the cavity is used to simplify the numerical simulation. However, in cases where the cavity lacks rotational symmetry resp. where attached components like couplers have to be taken into account, a fully three dimensional treatment of the Maxwell equations is necessary. This requires more computer power than is available on a normal high end workstation. Therefore, in the present approach a parallel SIMD super computer (APE-100) is used to compute the eigenmodes of accelerating cavities. As an example parts of the superconducting TESLA structure are investigated. The geometry input is parsed by MAFIA which transfers the resulting system matrix, incorporating geometry and material information, to the APE-100. The result of the diagonalization procedure is then read back to the MAFIA host where further data analysis and visualization can be done