Limits on the Contribution of Endogenic Radiolysis to the Presence of Molecular Oxygen in Comet 67P/Churyumov–Gerasimenko - UFR de Chimie de Sorbonne-Université Accéder directement au contenu
Article Dans Une Revue The Astrophysical Journal Année : 2018

Limits on the Contribution of Endogenic Radiolysis to the Presence of Molecular Oxygen in Comet 67P/Churyumov–Gerasimenko

Résumé

Radiolytic production has been proposed as a potential source for the molecular oxygen observed in comet 67P/Churyumov–Gerasimenko. Radiolysis can be exogenic or endogenic, the latter due to radionuclides present in the dust constitutive of the comet nucleus. We investigated the possibility of forming a significant amount of molecular oxygen through endogenic radiolysis. We applied a model of radiolytic production, developed for an Earth rock–water mixture, and improved it to account for the effect of the size of a radionuclide-bearing grain on the net radiation deposited in its ice mantle. We calculated the possible production of molecular oxygen considering the available experimental values of radiolytic yields. We found that endogenic radiolysis cannot account for the totality of the 3.8% (relative to water) O2 abundance derived from the ROSINA observations, with an end member case of our model producing at most a 1% abundance. By contrast, we predict H2O2 production leads to an abundance up to two orders of magnitude above observed values.

Dates et versions

hal-04039473 , version 1 (21-03-2023)

Identifiants

Citer

Alexis Bouquet, Olivier Mousis, Benjamin Teolis, Georgios Nicolaou, Ozge Ozgurel, et al.. Limits on the Contribution of Endogenic Radiolysis to the Presence of Molecular Oxygen in Comet 67P/Churyumov–Gerasimenko. The Astrophysical Journal, 2018, 864 (1), pp.9. ⟨10.3847/1538-4357/aad22f⟩. ⟨hal-04039473⟩
6 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More