Measurement of the near infrared xenon scintillation yield near atmospheric pressure

We have measured the xenon near infrared (NIR) scintillation yield in the wavelength range from about 700 to 850 nm for gas pressures from 0.3 to 1.5 atm. We have found the NIR yield to be nearly constant above 0.9 atm, increasing by about a factor of 4.5 as pressure is lowered to 0.3 atm. Measured in number of photons emitted we estimate that at 0.3 atm the NIR yield is 45% of the ultraviolet yield near 170 nm. The NIR yield may be sufficient to form the basis of detector systems utilizing low-pressure xenon gas.