Neutral gas temperature maps of the pin-to-plate Argon micro discharge into the ambient air

TL;DR

This paper maps the two-dimensional temperature distribution of an atmospheric argon micro discharge, revealing temperature gradients, discharge structure, and the coexistence of arc and glow discharges.

Contribution

It provides detailed temperature maps of a pin-to-plane argon micro discharge, highlighting the temperature variation and discharge structure with high spatial resolution.

Findings

Rotational temperature ranges from 1558 K to 2621 K.

Vibrational temperature ranges from 3010 K to 3775 K.

Identification of a double-layer discharge with arc and glow regions.

Abstract

This study is designed to explore the two dimensional temperature maps of the atmospheric argon discharge consisting of pin-to-plane electrodes supplied by a high voltage DC source. After checking the stability of the micro discharge, the two dimensional image plane focused by a quartz lens was scanned by the fiber probe driven by a 3D Mobile Platform. The rotational and vibrational temperatures are calculated using nitrogen emissions collected by the high resolution spectrometer and high sensitive intensified charge coupled device (ICCD). The rotational temperature varies from 1558.15 K to 2621.14 K and vibrational temperature varies from 3010.38 K to 3774.69 K, indicating a great temperature gradient due to small discharge size. The temperature maps show a lateral expansion and a sharp truncation in the radial direction. A double layers discharge is identified, where an arc discharge coats the glow discharge.