On the mechanism of the population of the $\mathrm{H}_2(d^3\Pi_u)$ state in nonequilibrium hydrogen plasma

The stationary concentration method is used to study the mechanism of population of the hydrogen $\mathrm{H}_2(d^3\Pi_u)$ state in a low-pressure nonequilibrium plasma in a DC glow discharge and a microwave discharge. This state is used in plasma diagnostics based on the emission of Fulcher system bands. The limits of the applicability of the coronal model for the population of this state are considered.