README 2008_08_20_wire_align1.1
Aug 19, 2008  DL
Aug 20, 2008  DL


This directory contains files used for a study of the 
overall tracking efficiency as a function of of the 
CDC stereo/axial configuration.

IMPORTANT: The directory labled "option-1" is not exactly
the CDC "option-1" that was coded up
during the Geometry V4 implementation in Jan. 2008. That
one had 25 layers with radii that were slightly different
than those in the most recent CDC design document which had
only 24 layers. The phase_shifted geometry supplied by
Beni incorporated the latest CDC design. The original 
comparison did not take this into account and ended up showing
essentially NO difference at all between the 2 designs.
This current study started with the phase_shifted geometry
and set all of the shifts to 0 and called that "option-1".

The option-2 geometry is also different than what appeared
in the Jan. 2008 XML. The differences were:

- The 25th layer was removed.
- Phase shifts were introduced

The close_packed_less_stereo geometry takes the close_packed
geometry and turns the outer 3 stereo layers into axial
layers.