(Total Internal Reflection Cherenkov)
 Summary of the Prototype Tests
- We have tested prototypes with radiators of 240 x 65 x 1mmt and also 2mmt using energy-degraded Ar & Kr beams between 170 ? 400 MeV/A.
- From the study on position & angle dependences, we decided to put PMT$B!G(Bs on both side of the radiator.
- From the energy dependence of the Cherenkov light yield, energy dependence of the velocity resolution is estimated. Effect of the TIR threshold is clearly seen. Velocity resolution of about 0.2% (rms), which is factor of 2 worse than necessary, was obtained.
- We also decided to use 2mm-thick radiator to cover the wider energy range.
- Using rigidity-analyzed ($B&$(Bp/p~0.1%) secondary beams at ~270 MeV/A, we have studied the mass separation. Isotopes around mass 70 could be separated with about 4$B&R(Bseparation for rigidity-analyzed secondary beams.
- Due to the thickness of the radiator (~1.2 g/cm2), reaction loss in the radiator is estimated to be about 5%.
- Prototype study shows that TIRC has enough mass resolving power below mass 80 around 270 MeV/A. But we have also noticed the radiation-damage effect.
ICB, plastic, Si-strip & TIRC @HIMAC