Study of helium-based drift chamber gases

The spatial resolution and dEdx resolution of several helium-based drift chamber gases have been measured and compared with an argon-based gas, ArC2H6 (50:50). The gases were investigated with a system of aluminum drift tubes using cosmic rays. The gases studied include various mixtures of helium and ethane, isobutane, and propane. The spatial resolution of the helium-based gases is better than that of ArC2H6 (50:50), while the dEdx resolution is comparable.