Straw Tracker
CAD model of one station inserted in the vacuum tank
- 4 stations
- 4 "views" in each station
- Each view has 448 (4x112) straws in each view
- -> 448x4x4 = 7168 straws
- Operate in vacuum at 1x10 -6 mbar
- 2.1m long with Di=9.8mm
- Mechanically independent straw
- Pretension in straws of 1.5 kg and two intermediate spacers for positioning. This is mandatory for the horizontal straws (x) and the straws at 45 degrees (u,v)
- Precise tracking (<120 µm)
- Hermetic for tracks -3° < O < 3°
- Particle rate in the straw: up to 0.5 MHz
- Non-flammable gas mixture CO2 (90%)+ CF4 (5%) + Isobutene (5%)
Section of straw layout in one view