Fast drift gases - CH4 and CF4
10 cm /ms
12 cm /ms
40 cm drift => ~ 3-4 ms Requires high drift field
CF4 -Ar
CH4
C2 H4
(1 KV/cm) (1 V/cm/Torr)
Fast Drift Gases - C2H2+CF4+Ar
MiniTPC SimulationN. Smirnoff (STAR)
• Single track• 35 pad rows (1.5 x 0.3 cm2)• Minimum number of hits 9• Reconstructed momentum• dE/dx smeared with 25% energy resolution• Dip angle correction• Truncated mean
e/p separation with CH4
0.25-0.4 0.4 - 1.0
1.0 - 1.2 1.2 - 2.5
• Single track• 35 pad rows (1.5 x 0.3 cm2)• Minimum number of hits 9• Reconstructed momentum• dE/dx smeared with 25% energy resolution• Dip angle correction• Truncated mean
MiniTPC SimulationN. Smirnoff (STAR)
e/p separation with C2H2+Ar
0.25-0.4 0.4 - 1.0
1.0 - 1.2 1.2 - 2.5