3 March 1995
To: Distribution:
From: Stan Ecklund
Subject: "IR +- 1m Engineering"  Meeting Notes 3 March 1995

Hobey explained away the conduction calculation discrepancy.  Both 
were done correctly; different input values explain the 
difference.

The thickness of the Be pipe is conservative with respect to 
collapse.  Dieter calculated the 0.8 mm thickness should be able 
to withstand 360 PSI.  However, if the Be is deformed an amount 
comparable to its thickness the failure point is at a much lower.

Hobey reported on CESR experience with water in their Be pipe.  
They will start with gas cooling and go to water if temperature 
monitoring indicates it is required.

Martin showed an updated drawing with the three tip mask.  We 
discussed moving the B1 permanent magnet blocks to smaller radii 
where allowed, and starting the blocks closer to the IP.  We also 
considered tapering the outer block side at 0.3 radian to gain 
space.  Dieter will explore the feasibility of this with a 
supplier he knows.  Martin will give Dieter a sketch of such a 
block.  

Tuesday March 14 we expect to have a joint Vertex Detector - IR 
meeting to report on the workings of this group.

No meeting on 3/10 due to BaBar collaboration Meeting.

Action Items:
1.  Refine the CAD drawing with proposed changes.
    Add imported vertex drawing. [Martin]
2.  More thermal calculations of mask-B1 cooling with actual 
    geometry when available.  [John H.]
3.  Number and location of holes in support barrel. [Gordon]
4.  HOM RF calculations with new mask geometry [S. Heifets]
5.  Design mask with cooling and B1 to avoid interference with 
    vertex detector cone if possible [Martin] .
6   Investigate feasibility of outer side of SmCo block at 300Êmr.

attachments: Transparencies

Next Meeting: 13:00 Friday  17 March 1995 in the Yellow room with 
TV to LBL