Primary scintillation yield and α/β ratio in liquid xenon

Scintillation of liquid xenon due to 5.486 MeV α-particles and 59.54 keV γ-rays, both emitted by a 241Am source, was observed. By measuring in the same spectrum the amplitudes Aα and Aγ corresponding to the peaks due to α-particles and γ-rays, respectively, the ratio of the scintillation yield for these two types of particles (in short, referred to as α/β) was found to be 1.07±0.02 at zero electric field. The mean energy expended per scintillation photon, i.e., Ws, in liquid xenon was determined as Ws=18.3±1.5eV for 59.54 keV γ-rays and Ws=17.1±1.4eV for α-particles. Using the available data on the dependence of the scintillation light yield of liquid xenon on γ-ray energy, the α/β ratio and Ws value were estimated for 1 MeV electrons.