GROUND MOTION MEASUREMENTS IN A HERA INTERACTION REGION

Ground motion is of great importance for the performance of any future Linear Collider, because it is a possible source of severe luminosity degradation. To estimate the expected detrimental effects and to define the requirements for feed-back systems, it is necessary to understand vibration prop-erties in an accelerator tunnel and especially in the interac-tion region. Therefore the HERA electron-proton collider has been taken as a realistic invironment to study groun