Well, i understand you postulated that it exists a kind of hysteresis by gas dissociation/reassociation/excitation, generating xsh..
in this way what kind of Rayleigh paper you referred ?
Below an easy reading to better understand how classic plasma is working... ( No Hysteresis..)
Display MoreRayleigh "Activated Gas" is not just plasma. There is a combination of ionisation, dissociation, and excitation. The effect is visible, and lasts for many minutes, when at very low pressure - which is how it was originally discovered, and studied.
The ionisation, dissociation, and excitation also happen at higher pressures - although probably in different proportions. However the subsequent thermalisation, recombination, and relaxation happen so quickly that the process isn't readily visible.
I've recently been looking at how these processes might affect gas behaviour in closed (Stirling & Ericsson) cycle machines - as there has always been a problem when analysing the cycles using classical thermodynamic theory (especially for small, high speed, machines that include regeneration). Although there aren't any electrical discharges in these machines, turbulence, thermal shock, and acoustic vibration will affect the gas molecules in extra ways that are not taken into account in classical kinetic gas theory.
I hope that explains why I've thrown Rayleigh into the possible hypothetical mix.