23 June 1995
To: Distribution:
From: Stan Ecklund
Subject: "IR +- 2m Engineering"  Meeting Notes 23 June 1995

Roy discussed earthquake requirements/impacts for the silicon 
vertex tracker.  He used a graph presented by Les Dittert at the 
integration meeting for acceleration vs. resonant period.  Roy 
estimates the flexure of the support tube will give 2.6 g 
accelerations at 11 Hz, and a corresponding angular motion of 2.6 
mradian.  This estimate scales from gravitational loading 
calculated by Gordon Bowden (memo 30 Jan 95 revision) with simple 
supports at the end of the tube.  The detailed earthquake 
calculation needs to be done before silicon can be ordered.  The 
2.6 mradian is small and could be accommodated.

Martin showed drawings of support tube with SVT and machine 
components. A BPM is shown along with space for vacuum pumps 
between B1 and Q1.  Space for SVT cables and Tungsten shielding is 
not resolved.  An interference of the Be pipe forward end needs to 
be fixed.  One of the drawings shows locations of fans on B1 LEB 
mask.

No x-y adjustment of the gimbals-ring support for the SVT is 
envisioned; it must be built to some tight tolerance like <500 
microns.  

Fred showed a cable routing for the case of a centered Q1.  
Bundles up to 2 cm thick occupy parts of the azimuth; on average 
cables take 1 cm radially.


Action Items:
1. Consider hybrid Q1 feasibility. [Martin, Stan, Mike, Gordon..]
2. Look for ways to reduce cable interference. [Roy, Alex]
3. Drawing Updates: [Martin Nordby, Fred Goozen]
     Shielding, cables in Q1 section
4. HOM RF calculations with new mask geometry.  [Eddie Lin]
5. Check that a rotated BPM misses synchrotron rad fan. [Mike]
6. Can we do with less shielding between B1 and Q1? [D. Coupal]
7. Required thickness of Q1 containment. [Martin]
8. Required thickness of Support Tube,
   calculate support tube deflection. [Martin]
9. Mask & B1 3d cooling calculation. [J. Hodgson]
10  Beam generated noise to the drift chamber. [D. Coward]

Next Meeting: 13:00 Friday  30 June 1995 in the Yellow room with 
TV to LBL

attachments: transparencies