TJNAF Hall A HRS Focal Plane Polarimeter

• 5 straw-tube wire planes
• SC1 and SC2 surround the gas Cerenkov counter.
  • 5200 channels / 5 chambers
• SC1 - amplifiers on 3 sides - gas tubes on 4th side,2tubes in series
  • gas in and out on same side - ~200-250kg
• SC2 - identical to SC1
• Analyzer: 60cm maximum
  • (slices of 1.9, 3.81, 7.62, 15.24, and 22.86 cm)
  • with thinner slices at the rear
  • 1.8g/cc =>
• 5 straw-tube wire planes