1月26日（火）13：30～15：00 太陽系小天体セミナー zoom
Jan 26 Tue Solar System Minor Body Seminar
1月27日（水）13：30～15：00 NAOJ Science Colloquium zoom
Jan 27 Wed
1月27日（水）15：00～16：00 ALMA-J seminar zoom
Jan 27 Wed
1月28日（木）13：15～15：15 博士学位論文審査会 zoom
Jan 28 Thu
詳細は以下をご覧下さい。
1月26日（火）
- キャンパス
- 三鷹
- セミナー名
- 太陽系小天体セミナー
- 定例・臨時の別
- 定例
- 日時
- 1月26日（火曜日）13時30分～15時
- 場所
- zoom
- 講演者
- 高橋昂希
- 所属
- 北海道教育大学
- 連絡先
- 名前：渡部潤一
- 備考
- テレビ会議またはスカイプによる参加も可
1月27日（水）
- Campus
- Mitaka
- Seminar
- NAOJ Science Colloquium
- Regularly Scheduled/Sporadic
- Every Wednesday
- Date
- 2021 January 27
- Time
- 13:30-15:00
- Place
- Zoom
- Speaker
- Renyu Hu (JPL)
- Title
- Characterizing atmospheric chemistry in temperate exoplanets
- Abstract
- The era of observationally characterizing temperate exoplanets and studying their atmospheric composition has begun. Hubble and JWST already have several candidate planets to study, and TESS may find another handful of temperate planets suitable for follow-up atmospheric observations. These temperate worlds are however very different from Earth – orbiting around a much cooler star, being substantially larger, or having different kinds of atmospheres. To guide observations, I couple atmospheric chemistry models with basic understandings of planetary climate and interior processes to determine the ranges of detectable atmospheric signatures and their implications. Recent progress will be discussed in this talk. I will show that on habitable-zone planets around late M dwarf stars like TRAPPIST-1, a small abundance of CO2 (often required to create a liquid-water ocean surface) would lead to a large abundance of O2 and CO in photochemical equilibrium. Because of this “O2-CO runaway”, habitable environments around late M stars likely entail an O2-rich atmosphere. I will also show that on larger and H-rich temperate planets (such as K2-18 b), photochemical processes based on CH4 and NH3 produce detectable abundances of HCN and N2O but little hydrocarbons in the observable part of the atmosphere. Lastly, I will discuss how future direct imaging observations using a starshade will enable the studies of temperate planets and their atmospheres around nearby stars.
- Facilitator
- -Name：Akimasa Kataoka
1月27日(水）
- Campus
- Mitaka
- Seminar
- ALMA-J seminar
- Regularly Scheduled/Sporadic
- Every Wednesday
- Date and time
- 2021 Jan 27 15:00-16:00
- Place
- Zoom
- Speaker
- Michihiro Takami (Institute of Astronomy and Astrophysics, Academia Sinica)
- Title
- Understanding the Physical Link between Mass Accretion and Jet Ejection in Active Young Stars
- Abstract
- Understanding the mechanisms for mass accretion and jet ejection is one of the key issues for star formation theories. However, observational studies are hampered by the limited angular resolutions of current telescopes, which are not sufficient to resolve the structure and kinematics in the jet launching region. We are therefore pursuing an alternative approach to tackle this important issue: long-term monitoring of mass accretion and jet ejection for active young stars. Our observations since 2010 include (1) near-IR IFU imaging spectroscopy of extended jets at a ~0″.1 resolution (Gemini-NIFS etc.); optical high-resolution spectroscopy to observe gas kinematics very close to the star (CFHT-ESPaDOnS etc.); and optical photometry to monitor changes in mass accretion rates with high time resolution. The results so far suggest that the jet-launching region is very close to the star, and associated with the stellar magnetic field. In my talk I will explain the outline of the project, our progress to date and our future plan.
- Facilitator
- Hiroshi Nagai, Xing Lu
1月28日（木）
- キャンパス
- 三鷹
- セミナー名
- 博士学位論文審査会
- 定例・臨時の別
- 臨時
- 日時
- 2021年1月28日（木）13:15～15:15（JST）
- 場所
- Zoom
- 講演者
- 石川裕之
- 所属
- 総研大 物理科学研究科 天文科学専攻
- タイトル
- Detailed Characterization of Nearby M Dwarfs with High-Resolution Near-Infrared Spectroscopy
- 連絡先
- -名前：大学院係 大村優美子