LAUSR

This work presents an investigation on the effects of the gap distance and working gas on the energy spectra of electrons (ESEs) in the atmospheric pressure plasma jets, and the corresponding mechanisms are also analyzed in detail based on the energy conservation of electrons in the development of discharge. The investigation is carried out by means of the numerical simulation based on a particle-in-cell Monte Carlo collision model and gives the following results. There are the same characteristics of the spatiotemporal evolution of the energy spectrum of electrons for the considered gap distances below 1 cm. For each gap distance, there is a characteristic time (CT) in the evolution of ESE. Before the CT, the peak value of ESE decreases, the peak position shifts toward high energy, and the distribution of ESE becomes wider and wider, but the reverse is true after the CT. With the decrease in the gap distance, the CT of ESE decreases, and the average energy of electrons (AEEs) increases. Small gap distanc...