Intense infrared scintillation of liquid Ar-Xe mixtures

Intense infrared (IR) light emission from liquid Ar-Xe mixtures has been observed using 12 keV electron-beam excitation. The emission peaks at a wavelength of and the half-width of the emission band is . Maximum intensity has been found for a 10 ppm xenon admixture in liquid argon. The conversion efficiency of electron-beam power to IR light is about 1% (10000 photons per MeV electron energy deposited). A possible application of this intense IR emission for a new particle discrimination concept in liquid noble gas detectors is discussed. No light emission was found for perfectly purified liquid argon in the wavelength range from 0.5 to on the current level of sensitivity.