Optical emission reference data for the GEC reference cell

A complete set of optical emission data for the gaseous electronic conferen ce reference cell (GEC) is presented for discharges at 75, 100, 150, and 20 0 V peak-to-peak and at pressures of 100, 250, 500, and 1000 mtorr, When th e GEC project was initiated, these were the setpoints that were to be exami ned, This paper provides a set of data that can he used as a comparison for other diagnostics. The emission is compared to metastable data obtained fr om laser-induced fluorescence in helium and argon and computer generated da ta of the argon metastable data. There is good agreement bet tr een these t hree sets of data and the profiles found in this paper, which can be used a s a consistency check for the capacitively coupled GEC reference cell, The data presented here were collected with an automated scanning sensor, which gathers wedges of optical emission (Ar I 750.4 nm), at ten vertical height s parallel to the bottom electrode surface. The digitized data was converte d to emissivity data as a function of radius using a Tikhonov regularizatio n method.