Gao, J (reprint author), Chinese Acad Sci, Inst High Energy Phys, Beijing 100049, Peoples R China.
In this paper a general procedure to determine linear collider parameters is given. As an example, a parameter list is proposed for ILC with very low bunch charge. The main aim of this paper is to demonstrate the beam parameter relations with the constraints from the interaction point and damping ring. It is suggested that the energy of the damping ring should be 7GeV instead of 5GeV if a 17km damping ring is to be used. However, if 6km damping ring (which is preferable) is adopted, 5GeV damping ring energy is reasonable.