Difference between revisions of "CDC Overview"

Revision as of 08:11, 2 November 2011

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 . There are also geometry tables in GlueX-document 979, however the numbers of straw layers, numbers of straws per layer and orientation are obsolete. The exact numbers are given above.

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

Draft v1.0 of CDC NIM paper.

Construction

Prototype Studies