Temperature dependence of the rotational relaxation cross-section in carbon monoxide

This Letter presents an investigation into the temperature dependence of the relaxation cross-section of the mean rotational energy, σrot, in carbon monoxide. Our data obtained in a free jet at 20–200 K together with high-temperature measurements made by other authors point to non-monotonic behavior of the rotational relaxation cross-section as a function of temperature. A theoretical explanation for such a behavior of σrot with temperature is offered.