Scintillation response of liquid argon to fission fragments

The relative luminescence intensities due to fission fragments and $\alpha$ particles from a ${}_{}{}^{252}{}_{}{}^{}\mathrm{Cf}$ source in liquid argon have been measured. A significant reduction of the luminescence yield due to fission fragments is observed. The ratios of the luminescence intensities per unit energy deposit due to light and heavy fission fragments to the luminescence intensity due to $\alpha$ particles are 0.244 ± 0.005 and 0.232 ± 0.005, respectively.