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Rough cut of EEMC SMD spacer geometry

Updated on Mon, 2009-09-14 11:31. Originally created by jwebb on 2009-09-10 10:34.
The SMD spacer is added to the EEMC geometry, as well as material in the front and back of each SMD plane.
 
1.0 Implementation of SMD plane + support material
 
Red triangles are the SMD strips.  These remain unchanged from previous geometry.
 
Black rectangles attached to base of each strip represent the material bonded to the front and back of each SMD plane.  This extra "backing" material is setup to have the same length of each SMD strip.  This creates the notches in the backing material just as they appear in the
smd strips.
 
The magenta lines indicate two things:
  1) The 1.2cm airgap into which each of the SMD planes is inserted
  2) The actual width of the SMD spacer in the adacent plane. 
 
 
 

 

2.0 Implementation of the SMD spacers

Spacers are setup to occupy the space unoccupied by the SMD planes.  The spacers are setup to extend +/- 5 degrees into the neighboring sectors.  By creating the SMD strips with the kONLY='MANY' option, the SMD strips will be given priority when geant performs tracking.  (i.e. the spacer will be cut out to follow the shape defined by the SMD strips.)

The magenta lines below indicate the start and end of the SMD spacers.

 

 

3.0 First look at materials observed by a geantino scan

Van Gough would be proud.  The ears in the spacer appear to be cut off.  Histogram 6230 should be the number of radiation lengths in the front material on the SMD.  6232 the "grey plastic" defined for the spacer.  (In both cases, these are just copies of poly).  The solid line shows the break point between spacer and SMD.

1) The spacer does not appear in the volume occupied by the SMD strips, as should be the case.

2) The spacer does not appear in the vacant region of the cut out.  This is not as intended.

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