Real Photon Collaboration Engineering Meeting

12/11/01

Minutes

Attendees: 

W. Olson, T. Weber, J. Weisend, M. Racine, P. Bosted

Items Discussed: 

1. P. Bosted has examined the E160 spectrometer design and the 
conclusion is that the best magnets to use are D3 and LASS. The 
results also indicate that having the iron wedge in LASS is 
preferable. It turns out that the optimum wedge length is 1.8 m 
long. Peter is still examining the optimum wedge shape. He will 
want to include copper on the sides of the wedge inside LASS. 
P. Bosted requires the size of the vertical aperture of the 
mirror plate to determine the optimal spacing between D3 and LASS.

2. The target will have to move a total of 150 cm inside D3 with 
the start point being flush with the magnet iron. The required 
precision of the z location of the target is roughly 1 cm.

3. Additional tradeoff studies are required but two likely 
candidates for the absorber material in the downstream half 
of D3 are graphite and boron.

4. We are still on schedule to freeze the E160 design and be r
eady for the LBL analysis in January 2002

New Action Items

1. J. Weisend will talk to D. Crabb about the possibility of 
coating the LiD2 to prevent exposure to air during assembly 
into the target system.

Ongoing Action Items
.
1. J. Weisend will work with D. Crabb and R. Principe to develop a 
detailed drawing showing the dilution refrigerator and the proposed 
superconducting magnet 
2. Number of cables required from the counting house to ESA. G. 
Oxoby will start tabulating these numbers based on the data 
acquisition memo and additional information from the collaboration.
3. P. Bosted will continue the physics simulations of the proposed 
change to the RPC design.
4. L. Keller will look at the muon backgrounds in the detector with 
the new RPC experiment design.
5. The interaction of the LASS magnet and all its iron with the 
E161/ E159 7 T target magnet needs to be carefully modeled using 
a 3-D field simulation.
6. Serious engineering of the shielding and earthquake supports 
associated with the LASS magnet must be started.

J. Weisend


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