Paschen's law studies in cold gases
  The break-through voltage over small gaps has been investigated for differing gap distances, gas pressures, and gas temperatures in nitrogen, neon, argon and xenon gases. A deviation from Paschen's law at micro gap distances has been found. The breakthrough behavior of the fill gas in colder environments was tested as well. A significant shift of the curve relative to the results at room temperature was observed. The results can be explained by combining Paschen's law and the ideal gas law. 
R. Massarczyk, P. Chu, S. R. Elliott, K. Rielage, C. Dugger, W. Xu
physics.ins-det