Beam separation in an asymmetric energy collider using a tilted experimental solenoid

The CERN-PSI feasibility study of a B-Meson Factory in the ISR tunnel has resulted in the proposal of a 3.5 on 8.0 GeV machine with a bunch spacing of 12 m, to be reduced eventually to 3 m. The beams will be vertically separated by the radial field component of the 1.5 T experimental solenoids, rotated for this purpose by 4 degrees, and by the fields acting on the off-centered beams in the central interaction region quadrupoles. Vertical separations of 6 σx are obtained at 3 m from IP, and of 2.5 σx at 1.5 m. The solenoid tilt and the amount of synchrotron radiation arriving in the central detector are compatible with the requirements of the experiments. The geometry and the performance of the proposed separation scheme are presented