| Title: |
High temperature cross-section determination and modeling of hot exoplanet atmospheres targeted by ARIEL ; Détermination de sections efficaces à hautes températures et modélisation représentative des atmosphères des exoplanètes chaudes ciblées par ARIEL |
| Authors: |
Poveda, Mathilde |
| Contributors: |
Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA (UMR_7583)); Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS); Université Paris-Est Créteil Val-de-Marne - Paris 12; Yves Bénilan |
| Source: |
https://theses.hal.science/tel-05351756 ; Autre. Université Paris-Est Créteil Val-de-Marne - Paris 12, 2023. Français. ⟨NNT : 2023PA120087⟩. |
| Publisher Information: |
CCSD |
| Publication Year: |
2023 |
| Subject Terms: |
Ariel; Absorption cross-Section; Exoplanets; Atmosphere; Section efficace d'absorption; Exoplanètes; Atmosphère; [SDU.OTHER]Sciences of the Universe [physics]/Other |
| Description: |
The large diversity of planetary worlds outside the Solar System has now been established since the discovery of the first exoplanet in 1995. Some of these extrasolar planets have the size of Jupiter and orbit at very close distances from their host star, which induces significant photochemistry within their atmospheres and temperatures as high as 2000 K. Therefore, they were called hot Jupiters. To understand how such planets formed and evolved over time, we need a better understanding of their physical and chemical characteristics. This is one of the main objectives of JWST (James Webb Space Telescope), which has already provided the first evidence of active photochemistry in the atmosphere of a hot Jupiter: WASP-39b. This will be also the main objective of the ARIEL (Atmospheric Remote-Sensing Infrared Exoplanet Large-survey) mission which is planned to be launched in 2029. Observations from these telescopes can be predicted and interpreted using photo-thermochemical models that calculate the atmospheric chemical abundance profiles. Unfortunately, some data used in these models are unknown at high temperatures. This is particularly the case for absorption cross sections which are used to quantify photochemistry. The main goal of my work was therefore to develop an experimental platform in the VUV field, in order to be able to measure absorption cross sections at temperatures up to 1200 K.The LISA “Exobiology and Astrochemistry” team has already undertaken the determination of absorption cross sections at high temperatures during synchrotron campaigns between 2010 and 2017 for the molecules of CO, CO2, NH3, HCN and C2H2. Increases of more than four orders of magnitude in the CO2 absorption cross sections between 300 and 800 K were thus observed. To expand this work, I have developed a new VUV spectroscopic platform at LISA. It is mainly composed of a deuterium lamp, a vacuum monochromator, a quartz cell inside an oven, and a photomultiplier to measure the output signal. After preforming several tests to define ... |
| Document Type: |
doctoral or postdoctoral thesis |
| Language: |
French |
| Relation: |
NNT: 2023PA120087 |
| Availability: |
https://theses.hal.science/tel-05351756; https://theses.hal.science/tel-05351756v1/document; https://theses.hal.science/tel-05351756v1/file/TH2023PA120087.pdf |
| Rights: |
https://about.hal.science/hal-authorisation-v1/ ; info:eu-repo/semantics/OpenAccess |
| Accession Number: |
edsbas.ACAF8D7A |
| Database: |
BASE |