Skip to Main content Skip to Navigation
Journal articles

Capacitively coupled plasma used to simulate Titan's atmospheric chemistry

Abstract : A complex chemistry in Titan's atmosphere leads to the formation of organic solid aerosols. We use a radio-frequency (RF) capacitively coupled plasma discharge produced in different N2–CH4 mixtures (from 0% to 10% of CH4) to simulate this chemistry. The work presented here was devoted to the study of the plasma discharge. In our experiment, the electron density is measured by the resonant cavity method and is about 1015 m−3 in pure N2 plasma at 30 W excitation RF power. It decreases by a factor of 2 as soon as CH4 is present in the discharge, even for a proportion as small as 2% of CH4. An optical emission spectroscopy diagnostic is installed on the experiment to study the evolution of the N2 bands and to perform actinometry measurements using Ar lines. This diagnostic allowed us to measure variations in the electron temperature and to show that a decrease in the density of the electrons can be compensated by an increase in their energy. We have also used an experimental setup where the plasma is tuned in a pulsed mode, in order to study the formation of dust particles. We observed variations in the self-bias voltage, the RF injected power and the intensities of the nitrogen bands, which indicated that dust particles were formed. The characteristic dust formation time varied, depending on the experimental conditions, from 4 to 110 s. It was faster for higher pressures and for smaller proportions of CH4 in the gas mixture.
Complete list of metadatas

https://hal.archives-ouvertes.fr/hal-00435793
Contributor : Catherine Cardon <>
Submitted on : Tuesday, November 24, 2009 - 6:00:03 PM
Last modification on : Friday, April 10, 2020 - 5:19:44 PM

Links full text

Identifiers

Citation

Grégoire Alcouffe, Marjorie Cavarroc, Guy Cernogora, Fakhreddine Ouni, Antoine Jolly, et al.. Capacitively coupled plasma used to simulate Titan's atmospheric chemistry. Plasma Sources Science and Technology, IOP Publishing, 2010, 19 (1), 015008 (11pp). ⟨10.1088/0963-0252/19/1/015008⟩. ⟨hal-00435793⟩

Share

Metrics

Record views

490