Detector Design Questions

• Any advantage in 3 layers versus 2? Two layers gives same resolution, and is more compatible with E161.
• To be compatible with E161, have 1 cm by 3 cm fingers. Turn long way for E161, short way for E160. J/psi resolution is not significantly affected by extra multiple scattering.
• Do we need a 45 degree layer for "ghost" ambiguities?
• How many E155x fingers and/or PMTs can we re-use?
• Do we need to have a dead zone on the beam plane due to large number of Bethe-Heitler muon pairs? Should there be special detectors here?
• How are background rates from all sources, especially neutrons.
• Are there any good detectors at Fermilab or elsewhere that we could use?