PAMPRE and the Chemistry of Neutral Species in Titan's Upper Atmosphere

David Dubois (1) , Nathalie Carrasco (1, 2) , Sarah Tigrine (1) , Ludovic Vettier (3) , Guy Cernogora (1)

1 PLANETO - LATMOS
2 IUF - Institut Universitaire de France
3 LATMOS - Laboratoire Atmosphères, Milieux, Observations Spatiales

A complex atmospheric photochemistry has been revealed in Titan’s atmosphere by the ongoing Cassini-Huygens mission. Its composition mainly made out of N2-CH4 leads to ionization and photo-dissociative processes that eventually form solid organic aerosols called tholins. Tholins are assumed to be formed in the ionosphere, where they coexist with the gas phase, in an ionic and neutral medium. The PAMPRE set-up aims at simulating the reactivity and production of solid aerosols in Titan’s ionospheric conditions through heterogeneous chemistry in a radiofrequency-induced plasma. In this study, our aim was to accumulate gas products in an N2-CH4 (90-10%) mixture using a cold trap to retain the products. These were then released after end of cooling and analyzed with infrared spectroscopy and mass spectrometry in order to better understand the chemical reactivity at work.

Keywords: Titan; Titan ionosphere; Experimental; Planetary atmospheres

Domains: Earth and Planetary Astrophysics [astro-ph.EP]

David Dubois, Nathalie Carrasco, Sarah Tigrine, Ludovic Vettier, Guy Cernogora. PAMPRE and the Chemistry of Neutral Species in Titan's Upper Atmosphere. Exobiologie Jeunes Chercheurs 2015, Nov 2015, Paris, France. 2015. ⟨insu-01336838⟩