CDC Design
Design Principle
- CDC covers angular region from 15 degrees to about 90 degrees
for good trigger efficiency to detect pion and proton pairs from
lambda particle decay.
All particles come to the angular region go through the outer window
of CDC to achieve good trigger efficiency for low energy protons.
- No sense wire at the forward angle to avoid irradiation by high rate
scattered protons.
An absorber also helps to reduce charged particles hit CDC at
the forward angle.
- CDC has 2 groups of axial layer and 2 groups of stereo layers.
Every axial layer group has 4 layers of sense wires, and every
stereo layer group has 3 layers.
- Ratios of width and thickness of cells in the 1st stereo layer are
smaller than 2.5.
- Typical cell thickness is 1 cm. The potential between sense and
potential wires can be obtained with an ordinary HV system.
Drawings and Photos