The quantum yield of O(1S) in CO2 photolysis retrieved from the Martian atmosphere
Publisher DOI
Abstract
Photochemistry studies the interactions between light and molecules. Ultraviolet radiation interacts with the atmosphere, and due to its energy, it can dissociate, excite, or ionize its constituents, which initiate other processes. A good knowledge of the interaction between photons of different energies with molecules and atoms is crucial for accurately modeling the atmospheric physics and for climate predictions. Despite its importance, photo-fragment dynamics lacks data because the experimental setup is difficult. We used the upper Martian atmosphere as a natural laboratory to measure the quantum yield O(1S) from CO2 + hν as a function of wavelength. We analyzed 4 years of continuous remote-sensing observations from the NASA MAVEN/IUVS spectrograph within a Bayesian framework analysis tool. We retrieved the quantum yield for the first time through its entire production spectral range, ≈80–126 nm, and achieved uncertainty from 10% to 20% on average. While at Lyman-α (121.6 nm), we achieved a precision of 2% by taking advantage of the properties of the upper Martian atmosphere.
Date Issued
2024-10
Publication Type
Article
Subject(s)
Subjects
tomic data
•
atomic processes
•
molecular data
•
Sun: UV radiation
•
planets and satellites: atmospheres
•
ultraviolet: planetary systems
Language(s)
en
Author(s)
Leonardos Gkouvelis |
Additional Credits
Journal
Astronomy & Astrophysics
Publisher
EDP Sciences
ISSN
0004-6361
Access(Rights)
open.access