1. Large Platforms For Push-pull Hitoshi Yamamoto 18-Sep-2007 IRENG07

2. Push-pull Experts seem to agree that, for a quick switch, detector, E-hut, and cryogenic system should be on a single platform. Detector needs space to move things (end caps, loading place to platform, etc.) around. Minimum disconnections in order for ‘commissioning/calibration’ to move in. Edges of platform = dead area → A large platform with full width of exp. hall. Service caverns are desirable for each detector.

3. beamline service cavern shaft Left detector on beamline Right detector is assembled as if non-pushpull detector E-hut

4. beamline service cavern shaft

5. beamline service cavern shaft Removable plug Support

6. beamline service cavern shaft Right detector on beamline

7. beamline service cavern shaft Both detectors being serviced

8. beamline service cavern shaft Another possibility for the shield design Half shields on air pads

9. Expensive design (Beijing ACFA07) Full exp. hall area is usable always

11. Some comments Installation more or less a la non-push-pull Connections from outside to platform are kept to minimum: powers mostly (no cold He). Separate platform helps isolation of vibration between two experiments. Thickness of platform ~ 2m : needs some protection at the edges (fences) + ladders.