Patterned Structure of Plasma Columns and Slices in a Dielectric Barrier Discharge

A patterned structure of plasma columns and slices with different electron densities and vibrational temperatures, which shows a dot-line square superlattice in the end view, is realized in argon/air dielectric barrier discharge at pressure from 0.52 to 0.86 atm and argon content larger than 90%. The electron density and the vibrational temperature are estimated by the Stark broadening of ArI line and the second positive band system, respectively. The electron densities of the column at the center of the square cell, the column at the vertex of the square cell, and the slice are in descending order, while the vibrational temperatures are in ascending order.