Electron-Cloud Effects in Transport Lines of a Normal Conducting Linear Collider

In the transport lines of a normal conducting linear collider, the long positron bunch train can generate an electron cloud which can then amplify intra-train offsets. This is a transient effect which is similar to the electron-cloud driven coupled bunch instabilities in a positron storage ring. In this paper, we study this phenomenon analytically. Some criteria on the critical cloud density with respect to given collider parameters are discussed.