Methane vibrational relaxation lifetimes at low temperatures

We have made photoacoustic measurements for the ν4 bending mode lifetime in methane in self collision over a temperature range of 146–293 K. We analyzed these results through a new theory using finite differences. Via a numerical transient analysis and a statistical evaluation of data we obtained similar results as those of earlier experimenters. Having proved the capabilities of our equipment we will direct future experiments to the study of methane deactivation by major gases present in the atmospheres of the large planets of the Solar System.