Magnetic shielding for the D0 detector solenoid upgrade

A proposal to add a superconducting solenoid to the D0 detector at Fermilab has recently been approved. During collider operations, the detector is currently traversed by beams from both the Tevatron and the Main Ring. The Main Ring beam is accelerating protons for antiproton production, while the Tevatron beams are colliding. In the event where the D0 solenoid upgrade would be completed before the Main Injector-a replacement ring for the Main Ring, located in a separate tunnel-the Main Ring beam would have to be shielded from the solenoid leakage flux. Using 3D calculations, we estimate that it would be feasible to keep the stray field along the Main Ring beam at level that would not cause orbit control or beam stability problems. We estimate the mechanical forces both on the solenoid and on the magnetic shield