MuCap Design

[Rick Luther <rluther@voyager.net>]

Dear Peter,

I am helping Larry with the MuCap gondola redesign, and he suggested I send 
you my model to let you see where we are heading.  We are using the same 
channel cross-section you guys had been using, but we have moved it 
radially outward so that it will be in line with the clamps on the mixers. 
We propose supporting the scintillators with a frame made of 1/2" and 3/4" 
medium-density polyethylene plates (specific gravity = 0.94).  The joints 
in the frame would be glued together with screws reinforcing each.  The 
ends of the channels will be bolted to the edge of two split polygonal 
rings which will serve to locate and support the gondolas.

We will not use Larry's split-ring clamps to support the mixers and PMTs 
because they don't easily accommodate PMT's that are not normal to the 
channels.  Something similar to your set-screw design would seem to be a 
reasonable choice for support.  However, we can't really proceed very far 
with the design until we know what the mounting rings for the mixers look 
like.  In your notes from last week's meeting you asked Dave Hertzog to 
send Larry one of these, but it hasn't arrived yet.  Can you expedite that 
for us?

I also have a question about the two circular rings or collars that are 
mounted around the PMTs in your model.  These appear to be intended as 
additional support in case the set screws in the main support loosen, in 
sort of a belt and suspenders arrangement.  Is that true, or have we missed 
something?

We appreciate any comments or suggestions you might have.

Regards,
Rick Luther

Gondola.zip