Date & Time: 2024/July/4 (Thu.) 17:00-18:00, Venue: Zoom TV Conference System. This is an informal seminar on the formation of stars and planets. We welcome anyone interested in the subject.
Abstract: Elemental abundances of planetary atmospheres encapsulate information on the past planet formation and evolution process. Successful launch of JWST now enables us to use the atmospheric compositions of not only our Solar System planets but also exoplanets for inferring past formation environments. Conventional studies have focused on the utility of atmospheric carbon and oxygen, while several recent studies suggested its limitation.
In this talk, I will highlight the utility of another element, nitrogen. To this end, I first introduce what formation environments the atmospheric nitrogen tells us for Jupiter in the Solar System. There is a long-standing mystery for the Jovian atmosphere: the atmosphere is enriched in both refractory elements (C, S, and P) and volatile elements (N and noble gasses) in a similar manner. I will introduce the previously proposed idea and its shortcomings, and then propose a new formation scenario to explain the Jovian atmospheric compositions.
To extend the availability of nitrogen for exoplanets, I conduct a series of photochemical calculations to investigate the planetary properties for which we can directly constrain atmospheric nitrogen abundance from ammonia abundance, the most abundant observable species containing nitrogen. We found that observable ammonia abundance is typically orders of magnitude lower than the actual nitrogen budget at a wide range of planetary age and mass, especially for a high metallicity atmosphere. This poses a caveat and necessity of chemical models for inferring nitrogen abundance in exoplanetary atmospheres. Lastly, I will introduce several recent JWST results that provide constraints on the nitrogen budget in exoplanetary atmospheres.
他、会議報告、速報など、飛び入りも歓迎します。今回もしくは次回以降、話題提供できる方は世話人までメールしていただけましたら幸いです。
Participants: 42, Affiliations: 14
Participants list:
Ibaraki: P Toru Turibe, P Munetake Momose
JAMSTEC: PD Sota Arakawa
Kagoshima: D2 Yudai Kobayashi, D2 Miyu Kido
Kobe: DA Kenji Kurosaki
Kyushu: D1 Ayumu Shoshi, D1 Shingo Nozaki, M2 Mitsuki Omura
Nagoya: P Shu-ichiro Inutsuka, AP Hiroshi Kobayashi, D3 Kanta Kitajima, D2 Ryushi Miyayama, D2 Tomotaka Nishikawa, D1 Izumi Seno, D1 Riona Yamada, M2 Kenshin Onogawa, M2 Wataru Takahashi, M1 Hayato Shimizu, M1 Kota Kobayashi, M1 Shusuke Utsumi, M1 Yuji Miko
NAOJ: P Hideko Nomura, PD Kazumasa Ohno, D3 Kiyoaki Doi, D2 Tomohiro Yoshida, M1 Naoya Kitade
NIT: Fukushima A Yuki Tanaka
Osaka: A Shinsuke Takasao
Shiga univ. of medical science: AP Kazutaka Motoyama
Tohoku: PD Daisei Abe
Tokyo Tech: PD Ryosuke Tominaga, D1 Yoko Ochiai, D1 Shintaro Taira
UTokyo-Komaba: P Takeru Suzuki
UTokyo: P Yuri Aikawa, PD Naoto Harada, A Shota Notsu, D3 Kaho Morii, D3 Yoshihide Yamato, D2 Lily Ishizaki, D1 Yuto Komichi
次回：2024/Aug./29 17:00-
連絡世話人：冨永遼佑（東工大） tominaga.r.aa[at]m.titech.ac.jp