CDC Overview
The GlueX CDC
Overview
The CDC is a straw tube chamber that sits around the target in the
GlueX experiment. The straws nominally run parallel to the beamline
with readout on the upstream end of the chamber. About half of the straws
are tilted with a 6 degree stereo angle to provide a measurement of the
z position in two regions along the track. Tracks going more forward than
about 30 degrees will also be tracked by the forward drift chamber system
in the GlueX detector (FDC).
The 1.6 cm diameter straws are arranged in 28 radial layers. The inner-most
layer is at about 10 cm and the outermost is at about 57 cm from the beamline.
The chamber is anticipated to achieve a 150 micron position resolution in
the r-phi plane, which when conbined with the stereo information will yield
a number of z measurements with resolution of about a mm.
Row#......Straw#............Orientaion
1 42 A 2 42 A 3 54 A 4 54 A 5 66 -S 6 66 -S 7 80 -S 8 80 -S 9 93 S 10 93 S 11 106 S 12 106 S 13 123 A 14 123 A 15 135 A 16 135 A 17 146 -S 18 146 -S 19 158 -S 20 158 -S 21 170 S 22 170 S 23 182 S 24 182 S 25 197 A 26 197 A 27 209 A 28 209 A
sum 3522
The description of the CDC is found in GlueX-document 990
which can be found on the portal http://portal.gluex.org, however the exact
numbers of layers an so forth are obsolete. A more up to date list of numbers
and geometry tables can be found in the latest version of GlueX-document 979.
General information on charged particle tracking in Hall-D can be found on the Charged Particle Tracking wiki page.
The CDC is being built by the Medium Energy Physics group at Carnegie Mellon University http://www.cmu.edu . The current members of the CMU group involved in this effort are:
- ) Curtis A. Meyer cmeyer@ernest.phys.cmu.edu
- ) Gregg Franklin gbfranklin@cmu.edu
- ) Yves Van Haarlem yvhaarle@ernest.phys.cmu.edu
- ) Naomi Jarvis nsj@cmu.edu
- ) Gary Wilkin wilkin@ernest.phys.cmu.edu
