Circuit and scattering matrix analysis of the wire measurement method of beam impedance in accelerating structures

In order to measure the wake field left behind multiple bunches of energetic electrons we have previously used the ASSET facility in the SLC. However, in order to produce a more rapid and cost-effective determination of the wakefields we have designed a wire experimental method to measure the beam impedance and from the Fourier transform thereof, the wakefields. In this paper we present studies of the wire effect on the properties of X-band structures in study for the JLC/NLC (Japanese Linear Collider/Next Linear Collider) project. Simulations are made on infinite and finite periodical structures. The results are discussed.