12月15日（火）13：30～15：00 太陽系小天体セミナー zoom
Dec 15 Tue Solar System Minor Body Seminar
12月16日（水）15：00～16：00 ALMA-J seminar zoom
Dec 16 Wed
詳細は以下をご覧下さい。
12月15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
- 12月15日（火曜日）13時30分～15時
- 場所
- zoom
- 講演者
- 匠あさみ
- 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
12月16日（水）
- Campus
- Mitaka
- Seminar
- ALMA-J seminar
- Regularly Scheduled/Sporadic
- Every Wednesday
- Date and time
- 2020 Dec 16 15:00-16:00
- Place
- Zoom
- Speaker
- Takuma Izumi
- Affiliation
- NAOJ
- Title
- ALMA Observations of Multiple CO and C Lines toward the Active Galactic Nucleus of NGC 7469: An X-ray Dominated Region Caught in the Act
- Abstract
-
We used the ALMA to map multiple 12CO, 13CO and C emission lines around the type-1 active galactic nucleus (AGN) of NGC 7469 at ~100 pc resolutions.
The CO lines are bright in both the circumnuclear disk (central ~300 pc) and the surrounding prominent starburst (SB) ring (~1 kpc diameter).
By contrast, [CI](1-0) line is strongly peaked at the AGN.
Consequently, we found strikingly different brightness temperature ratios between the AGN and the SB ring, for example,
[CI](1-0)/13CO(2-1) is ~20 at the AGN and ~2 at the SB ring.
Our local thermodynamic (LTE) and non-LTE analyses indicate that the enhanced line ratios (or CI-enhancement) are due to an elevated C/CO abundance ratio and temperature around the AGN as compared to the SB ring.
This accords well with the picture of the X-ray dominated region (XDR), which can be formed around an AGN.
Our results suggest that the CI-enhancement is potentially a good marker of AGNs that could be used in a new submm energy diagnostic method toward dusty environments.
I will also briefly discuss our on-going efforts for future programs, including ALMA cycle 8 and the coming ngVLA. - Facilitator
- :
Daisuke Iono, Andres Guzman