Effect of the gas contamination on CF4 primary and secondary scintillation

The effect of gas contamination on light emission properties of CF4 is presented. The study was performed in the UV (220–450 nm) and visible (450–800 nm) wavelength ranges and the relative light emission intensity and effective decay times were measured. Gas contamination effects, as well as the effect of controllable addition of small quantities of gas admixtures were investigated for both the primary and secondary scintillation. The primary ionization was produced by alpha-particles from an Am-241 alpha source, and MSGC plates were used for electron multiplication and secondary light production. Two types of commercial gas purifiers were tested.