Real Photon Collaboration Engineering Meeting 10/16/01 Minutes Attendees: P. Bosted, T. Weber, W. Olson, R. Arnold, J. Weisend Items Discussed: 1. R. Arnold is working on the dump line wire array design. He and R. Rogers will start building a prototype in the near future. The design is 95% like the previous array but using radiation hard components. 2. G. Oxoby and R. Arnold have looked at possible cable runs for the photon beam line. They have identified a candidate conduit for running cables from the dump magnet area up to the counting house. Cabling for the goniometer region is further upstream from the dump magnets and the cable runs from the goniometer will probably be determined by the allowable cable lengths. 3. For E160, P. Bosted has studied using D3 containing just the target followed by the LASS magnet filled with iron. It is desirable to put D3 as close as possible to the LASS magnet but there are questions regarding the resulting magnetic forces. It may be best to have 2 target positions in D3 depending on the beam energy. P. Bosted will continue to examine this issue. 4. For E161, we would put the polarized target at the D3 location and put an additional small magnet ( 29D36) between it and the LASS magnet. Again, there is a question of allowable magnetic forces. It would be useful to have a drawing of how the dilution refrigerator fits inside the proposed superconducting magnet. Decisions Reached New 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. Ongoing Action Items . 1. 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. 2. P. Bosted will continue the physics simulations of the proposed change to the RPC design. 3. L. Keller will look at the muon backgrounds in the detector with the new RPC experiment design. 4. 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. 5. Serious engineering of the shielding and earthquake supports associated with the LASS magnet must be started. J. G. Weisend II 2