Speaker
Description
Both the spectrum and primary scintillation yields of Argon-CF4 mixtures have been measured with an x-ray tube and an alpha source, respectively, in a broad range of concentrations and pressures. In the studied range of 220-800 nm, these mixtures scintillate mainly in four bands centered on 260, 290, 370 and 625 nm. Scintillation is clearly noticeable for as little as 0.1% of CF4 in the mixture, part of it being attributable to transfer reactions between the excited argon states and the CF4 molecules.
The large scintillation yields and short time constants of the emission, together with spectral characteristics that are suitable for SiPM detection, could in principle allow time tagging in large-volume Ar-based gaseous TPCs down to an energy threshold around 1 MeV, with ns-resolution.
