Progress Report of Region3


1) VDC drawings

- still ongoing ....

2) Geant4 simulation progress
 
- Checked for the max. possible size of the VDC, so the frame (+preamps) will not be hit by electrons of the adjacent octant (elog)
   Result:  Max VDC length  allowed : 280cm (250cm inner length + 2*15cm frame)
              
(Pic below shows a dual VDC (yellow) with a total length of 300cm. The lower left bottom edge of the frame is exposed to electrons)



(Pic below shows the dual VDC's with the nominal 230cm overall length [200cm inner length + 2*15cm frame])


- Started to implement CAAD into QweakSim for GEANT4->STEP file export (elog)

   There is an annoying problem with Geant4 that the current driver for visualization does not work correctly for boolean solids.
    Whem you create e.g. the geometry of the upstream main magnet support structure using many boolean operations (union/subtract)
    the visualization is corrupted, it does not *show* the geometry of what you have defined (visualization bug does not affect tracking).

    Famous example is the geometry of the Qweak handlebar cerenkov detector: tracking is fine, but one of handles is not visualizied.

    I'm almost done with the implemtation, the CAAD code has to be adapted to the more stringend rules of  the current compiler (gcc => 3.3.5).
    The advantage of CAAD/OpenCascade is that the Geant4 geometry can be checked with any CAD program. This procedure was done is the early
    version of the G0-GEANT, that's why we still use an Euclid file format for Geant3
    (Geant3->Euclid->ACAD using euc2acd available on http://www.npl.uiuc.edu/ftp/G0/computation/g0geant/  )

3) Progress on the Wire Scanner

   - Designing the optics for resolving a 25um wire with a 1/3" CCD chip (elog)

4) Cleanroom progress

  - clear out of the photolab, cleaning the clean room (elog)

That's all folks !