From MORSE@BNLAJC.BNL.GOVWed Oct 30 08:20:18 1996 Date: Tue, 22 Oct 1996 20:53:43 -0400 From: "William M. Morse" To: benante@BNLDAG.AGS.BNL.GOV, stratos@bnl.gov, messier@buphy.bu.edu, curcio@bnl.gov, mizumach@ee.kagu.sut.ac.jp, scmag@lbl.gov, direttore@sns.it, roberts@BNLDAG.AGS.BNL.GOV, YIM@inp.nsk.su Subject: Minutes of Vacuum Integration Workshop Minutes of October 22, 1996 Vacuum Integration Meeting Mike Mapes reviewed the vacuum procedures given in g-2 note 136. Bill Morse reviewed the single point storage ring ground described in g-2 note 211. Klaus Jungmann reviewed the status of the NMR plunging probes, beamtube trolley, parking garage, and trolley drive. One issue is the variation in the height of the bottom trolley rail. With the present design, the distance from the bar code reader on the trolley to the bar code on the trolley rail frame has a tolerance which is close the the rail variation of +-0.5mm. Klaus will get together with Yannis and Lou to look at the rails and review the rail survey data. The two cable solution has been tested at Heidelberg and works. The one cable solution (for compatibility with the muon kicker) is being worked on. The two cable solution is fine for the first run which will be pion injection, since the prototype kicker tests are continuing trying to understand the various kicker technical problems. Klaus will meet with Lou to go over some trolley drive and parking garage questions. The Field Measurement and Control team has specified two plunging NMR probes and one calibration probe. Klaus reported Hiedelberg has built and tested the two plunging probes. Yale was not represented at the workshop to report on the calibration probe progress. We thanked Klaus for sending the Heidelberg super- tech Ralf Zigler to BNL to work on the trolley rail frame for three weeks. He did a truly outstanding job! Lou presented the latest beam vacuum chamber drawing. The final location of the two beam chamber turbo pumps were indicated (chambers 12 and 6). Cryo pumps will be located in chambers 3 and 9. There will be an additional turbopump at the trolley drive. Lou next described the status of the collimators. We have made nine collimators. The beam dynamics calculations have assumed collimators in the bellows of chambers 4-12 inclusive. However, the chamber 4 collimator is not compatible with the kicker (not too surprising). This collimator can be moved to chamber 1. The beam dynamics team will study this. With the present design, the collimators will be in the theoretically correct position +-0.5mm. There will be no in-situ radial or vertical adjustment, except they can be swung vertically up so the trolley can pass. Therefore, we can take muon data with from zero to nine collimators rotated in. It would be possible to design an in-situ radial adjustment device; however, this would take time and effort. It was decided not to design this device for the first run unless the beam dynamics team thought it was necessary (Lee said quite emphatically he didn't think it was necessary for the first run). We are not precluded from adding it for the second run. Paul Debevec discussed the mylar traceback chamber vacuum window. For safety purposes, it should be thicker than about 0.007". For physics considerations, it should be thinner than 0.010 - 0.020". It looked like we had a consistent solution. However, Mike Mapes tested a 0.007" (I think) window and concluded the diffusion was too great for -7 Torr range vacuum. He will test thicker windows, and communicate with Paul to arrive at a consistent solution. Ofer Rind discussed the fiber beam monitors. One issue was whether there would be too much of a light leak from the traceback vacuum window which is right next to the 270 degree fiber monitor station. Chen Pai reviewed the muon kicker design. The major issue was the Q1 quadrupole/ kicker interface. Since the kicker plates extend into the bellows, there is only 10cm space between the quad and kicker plates. The quad and kicker teams will get together to determine if this is an acceptable solution. Respectfully submitted - Bill Morse.