Near-infrared scintillation of liquid argon
  Since the 1970s it has been known that noble gases scintillate in the near infrared (NIR) region of the spectrum (0.7 $\mu$m < $\lambda$; < 1.5$\mu$m). More controversial has been the question of the NIR light yield for condensed noble gases. We first present the motivation for using the NIR scintillation in liquid argon detectors, then briefly review early as well as more recent efforts and finally show encouraging preliminary results of a test performed at Fermilab. 
T. Alexander, C. O. Escobar, W. H. Lippincott and P. Rubinov
physics.ins-det hep-ex