Electron Avalanche and Streamer Processes Near a Dielectric Interface with Variable Photo-Electron Emission*

The effects of secondary photo-electron emission from a dielectric surface on electron avalanche and streamer processes are modeled in air at 760 Torr via an electrostatic PIC code which simulates particle-particle collisions using the DSMC method. A quasi-neutral seed plasma is placed near the cathode end of a 2 mm gap. The air chemistry model$^{\mathrm{1}}$ includes Townsend breakdown and streamer mechanisms, tracking excited state neutrals that can either undergo quenching collisions or spontaneous photon emission transitions$^{\mathrm{2}}$.~Initial results suggest that photoemission can significantly affect streamer evolution along the dielectric$^{\mathrm{3}}$.$^{\mathrm{\thinspace }}$[1] C. Moore \textit{et al.}, ``Development of Kinetic PIC-DSMC Model for Breakdown in the Presence of a Dielectric'', ICOPS, Banff, 2016. [2] A. Fierro \textit{et al.}, ``Discrete Photon Implementation for Plasma Simulations,'' Physics of Plasma, 23, 013506, 2016. [3] A. Jindal \textit{et al.}, ``Streamer Formation Near a Dielectric Surface with Variable Quantum Efficiency'', ICOPS 2017.$\varepsilon $