###### Abstract
The temperature dependence of the rate coefficients of N\({}_{2}\) and O\({}_{2}\) dissociation and ionization reactions governed mainly by the plasma's free electrons was further explored in the work of [PERSON] et al., who developed a hydrodynamic chemical non-equilibrium model of a pulsed discharge [27]. A chemical non-equilibrium is generally related to diffusive and convective transport processes as well as radiation [28] and is more pronounced the greater the separation between the electron and heavy particle temperature [29,30], which can be expected when the plasma interacts with other non-plasma media of higher mass density (for example, a treated surface) [31]. The model presented in [27] was further developed by [PERSON] into a time-dependent two-temperature chemical non-equilibrium model. According to the author, several dissociation and ionization forward reactions are governed by a different temperature than the corresponding backward reactions when both thermal and chemical non-equilibriums are taken into account [32]. This, of course, increases the complexity and computational cost of such a model [31] but also indicates the need for experimental determination of plasma parameters for validation purposes. An even deeper analysis of the influence of different temperatures (especially of the nitrogen vibrational states) on the chemistry of plasma can be found in [33]. Based on an analysis of recent research trends [2,3], the need for comprehensive characterization of non-thermal plasmas is gaining importance as new application fields are targeted, particularly in the environmental and health domains. For example, in the recently popular research topic of plasma-activated water, due to the ability of such water to inactivate biofilm contamination in food, water, and medical applications [4,17,34,35], the plasma-water interface adds complexity to the analysis of the observed effects. The reactive species generated in the gaseous plasma dissolve in the water to form long-lasting aqueous species that enhance the antibacterial activity of such a plasma-treated water [4,24,36,37]. Thereafter, as reported by [PERSON] and his co-workers, the concentration of the reactive species in water is determined not only by the concentration of species produced in the plasma but also by the solubility coefficients determining the transport into the aqueous medium [24]. Since the production rate of reactive nitrogen and oxygen species depends on the power consumed by a discharge [24,38], and thus on the electron density and temperature [35], a thorough plasma characterization is a key element for the overall understanding of the observed effects. Another recent application for which plasma characterization seems to be important is, for example, the conversion of CO\({}_{2}\) into synthetic fuels [22]. A low-current, high-voltage discharge operated with nitrogen at atmospheric pressure has been characterized by the authors of this paper by means of emission spectroscopy and laser scattering recently [39; 40]. In this work, different pulse frequencies and pulse current amplitudes are investigated using laser scattering diagnostics and emission spectroscopy to assess their influence on the behavior of the characteristic plasma parameters, i.e., electron density (\(n_{e}\)), as well as electron (\(T_{e}\)) and heavy particle (\(T_{h}\)) temperatures. By synchronizing the scattering setup with the operating frequency of the plasma generator, information about the temporal progression of the characteristic values is obtained. Thereafter, the scattering results are compared with emission spectroscopy and data published for related discharge types.