ABSTRACT
Early attempts to model plasmas were based on zero-dimensional and phenomenological models. An example of this approach is the circuit model, which represents plasma behavior using passive circuit elements, resistance, capacitance, and inductance. Although such an approach is useful for representing specific plasmas and studying how they behave once connected to the external circuit, it is beyond the scope of this chapter to specify plasma characteristics intrinsic in a feed gas molecule. There is a rate equation model describing zerodimensional plasma, which has proven quite useful for the kinetic optimization of a gas laser, mainly by utilizing a bulk plasma.
