The Importance of the Discharge Current in the Formation of the Pink Afterglow of a Nitrogen DC Discharge

conference paper

English

In this work we have used optical emission spectroscopy to measure the (2-0) 1st positive system emission in nitrogen DC discharge at pressure p=1000 Pa, for discharge currents in the range I=50-200 mA, in a Pyrex tube with internal diameter (2R)=13 mm. It is shown that an important difference in behaviour occurs when the discharge current is increased from 50 to 70 mA. As a matter of fact, at 50 mA the pink-afterglow, characterized by the raise in the optical emission after a dark zone, does not exist, only the well known yellow-afterglow being visible. The former is a result of the vibration-vibration (V-V) up-pumping followed by vibration-to-electronic (V-E) energy exchanges, whereas the latter is a result of 3-body N-atom recombination. However, for 70 mA and higher currents the pink-afterglow exists and gets more noticeable as the current increases.

nitrogen pink afterglow, numeric simulation, optical emission spectroscopy

SOURAL, I.; GUERRA, V.; LINO DA SILVA, M.; SÁ, P.; KRČMA, F.

2009

29. 6. 2009

EPS

Sofia

2-914771-61-4

Proceedings of 36th European Physical Society Conference on Plasma Physics

P2-103-1

P2-103-4

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