Drift Chamber
Cross-section view of the PHENIX detector
The frame of the Drift Chamber
Detector Overview
The PHENIX drift chamber was a multiwire gaseous detector located at a radial distance of 2.02 < R < 2.48 m. There was one chamber on each arm, and they were mirror copies of each other, each one subtending 90° in azimuth and 2 m along the z direction. The DC measured the trajectories of charged particles in the r-φ plane in order to determine their charge and transverse momentum pT . A detailed description about PHENIX Drift Chambers (DC) can be found in the following publication.
Publications
- Low-mass Drift Chambers of the PHENIX central spectrometers at RHIC (NIM A 494, 2002, doi.org/10.1016/S0168-9002(02)01464-X)
- PHENIX Central Arm Tracking Detectors (NIM A 499, 2003, doi.org/10.1016/S0168-9002(02)01952-6)
Presentations
PHENIX Focus: The PHENIX Drift Chamber (Sergey Butsyk)
Variables and Accessors under PHCentralTrack Node
| Type | Name | Description |
|---|---|---|
| int | get_npart | Total number of tracks/particles in a givem event |
| short | get_quality | Quality of the Drift Chamber tracks |
| float | get_zed | z coordinate at which the track crosses PC1 |
| float | get_phi | phi coordinate at which the track crosses the drift chamber reference radius |
| float | get_alpha | Inclination of the track w.r.t. an infinite momentum track. Hence, pT is roughly proportional to 1/alpha. This value comes from the straight line fit and does not respect residual bends |
| float | get_beta | This is essentially the spherical coordinate "THETA" of the track vector as it passes through the drift chamber reference radius |
| float | get_phi0 | Track's phi direction at the vertex |
| float | get_the0 | Track's theta direction at the vertex |
| float | get_mom | Magnitude of the momentum |
| float | get_px | Momentum along X-direction |
| float | get_py | Momentum along Y-direction |
| float | get_pz | Momentum along Z-direction |
| float | get_E | Energy estimated using DC |
| short | get_charge | Returns charge of the track |
