Nov 8 Tue 10:00～11:30 太陽系小天体セミナー Zoom
Nov 9 Wed 10:30～12:00 SOKENDAI Colloquium Zoom
Nov 9 Wed 15:30～17:00 NAOJ Science Colloquium Zoom
詳細は以下をご覧下さい
11月8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：11月8日（火曜日）10時00分～11時30分
場所：zoom
講演者：匠あさみ
世話人の連絡先
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
11月9日（水）
Campus：Mitaka
Seminar：SOKENDAI Colloquium
Regularly Scheduled/Sporadic：Regular
Date and time：November 9, 2022 10:30-12:00
Place：Zoom
Speaker : Shunsuke Sasaki
Affiliation: SOKENDAI 4th year (D2) (Supervisor: Tomoya Takiwaki, Mami Machida, Takashi Moriya)
Title: turbulent effects in core collapse supernova
Speaker: Shiori Koshisaka
Affiliation: SOKENDAI 2nd year (M2) (Supervisor: Takayuki Kotani, Misato Fukagawa, Yasunori Hori)
Title: Study on Disks around Young Stars by the Fast PDI mode of SCExAO
Facilitator
-Name：Matsuda, Graduate Student Affairs Unit
11月9日（水）
Campus：Mitaka
Seminar：NAOJ Science Colloquium
Regularly Scheduled/Sporadic：Every Wednesday
Date and time：2022 Nov. 9, 15:30-17:00
Place：zoom
Speaker：Alessio Traficante
Affiliation：INAF Rome
Title：From filaments to clumps: multi-scale dynamics in 70 micron quiet star-forming regions
Abstract：”The star formation mechanism occurs in well defined structures that can be identified and studied in great details in our own Galaxy: the process starts in giant molecular clouds, objects extended up to several tens of parsecs, within which elongated sub-structures, called filaments, may form. Inside filaments, round-like condensations extended up to ~1pc in radius, the so-called clumps, are the natural birth site of the pre- and proto- stellar cores, inside which will origin the future stars.
There are still many open questions in this hierarchical view of the star formation process: are these structures relatively confined from each other? Or is the large-scale environment affecting the dynamics of the formation down to clumps and cores? Is there a continuous interplay of the various forces involved in the process, namely turbulence, gravity and magnetic fields, at all scales? Or is there a relevant scale at which gravity will start to dominate the collapse, with critical implications on the star-formation mechanism?
After a general overview of the problem, I will present in details some recent results focused on the interplay between gravity and turbulence at the filament and clump scales. To investigate this interplay we have combined the dynamics of so-called 70 micron quiet clumps, i.e. very pristine regions not yet strongly affected by feedbacks, with the dynamics of the parent filaments in which they are embedded. Both clumps and filaments physical properties have been extracted from the Herschel survey of the Galactic Plane, Hi-GAL. The kinematics of filaments have been taken from ancillary CO data, while the kinematics of clumps has been studied with dedicated surveys carried out with the IRAM 30m telescope and aimed to observe high-density tracers such as N2H+ (1-0) an HCO+ (1-0).
We observe a continuous interplay between turbulence and gravity, where the former creates structures at all scales and the latter takes the lead above a critical value of the surface density is reached, ~ 0.1 g cm^-2. In the densest filaments this transition can occur at the parsec, or even larger scales, leading to a global, gravitationally driven collapse of the whole region and to the formation of the most massive objects in the Galaxy.
Facilitator
-Name：Akimasa Kataoka
Comment：English,