Limits on the Contribution of Endogenic Radiolysis to the Presence of Molecular Oxygen in Comet 67P/Churyumov-Gerasimenko
(2018) In Astrophysical Journal 864(1).- Abstract
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... (More)
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.
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- author
- Bouquet, Alexis ; Mousis, Olivier ; Teolis, Benjamin ; Nicolaou, Georgios ; Ozgurel, Ozge ; Pauzat, Francoise ; Ellinger, Yves ; Ronnet, Thomas LU and Waite, J. Hunter
- publishing date
- 2018-09-01
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- astrochemistry, comets: individual (67P/Churyumov-Gerasimenko)
- in
- Astrophysical Journal
- volume
- 864
- issue
- 1
- article number
- 9
- publisher
- American Astronomical Society
- external identifiers
-
- scopus:85053165472
- ISSN
- 0004-637X
- DOI
- 10.3847/1538-4357/aad22f
- language
- English
- LU publication?
- no
- id
- 87470563-c9c2-48e6-bdd8-acb2cd308c7f
- date added to LUP
- 2019-05-29 09:23:50
- date last changed
- 2022-03-18 01:02:50
@article{87470563-c9c2-48e6-bdd8-acb2cd308c7f, abstract = {{<p>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) O<sub>2</sub> abundance derived from the ROSINA observations, with an end member case of our model producing at most a 1% abundance. By contrast, we predict H<sub>2</sub>O<sub>2</sub> production leads to an abundance up to two orders of magnitude above observed values.</p>}}, author = {{Bouquet, Alexis and Mousis, Olivier and Teolis, Benjamin and Nicolaou, Georgios and Ozgurel, Ozge and Pauzat, Francoise and Ellinger, Yves and Ronnet, Thomas and Waite, J. Hunter}}, issn = {{0004-637X}}, keywords = {{astrochemistry; comets: individual (67P/Churyumov-Gerasimenko)}}, language = {{eng}}, month = {{09}}, number = {{1}}, publisher = {{American Astronomical Society}}, series = {{Astrophysical Journal}}, title = {{Limits on the Contribution of Endogenic Radiolysis to the Presence of Molecular Oxygen in Comet 67P/Churyumov-Gerasimenko}}, url = {{http://dx.doi.org/10.3847/1538-4357/aad22f}}, doi = {{10.3847/1538-4357/aad22f}}, volume = {{864}}, year = {{2018}}, }