Abstract
This paper presents results on the computation of Higher Order Modes(shortly HOMs) in the designs for the accelerating structures which have already been built in into the TESLA [1] Test Facility (TTF) or are presently being studied as final design for the TESLA collider.
Depending on the complexity of the studied arrangement different computational strategies are followed: 1. the use of commercial software packages like MAFIA [2] or CST Microwave Studio (MWS) [2] on workstations, and 2. a recently implemented tool for Coupled S-Parameter Calculation (CSC) which easily allows to calculate the scattering properties of rf-sections connected to each other with arbitrary topology or to determine eigenmodes of resonating structures.