10月16日（火）13：30～15：00 太陽系小天体セミナー 南棟２階会議室
Oct 16 Tue Solar System Minor Body Seminar Conference Room, South Bldg.2F
10月16日（火）14：30～15：30 理論コロキウム 講義室
Oct 16 Tue DTA colloquium Lecture room
10月17日（水）10：30～12：00 総研大コロキウム 講義室
Oct 17 Wed SOKENDAI colloquium Lecture room
詳細は以下をご覧下さい。
10月16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
- 10月16日（火曜日）13時30分～15時
- 場所
- 南棟２階会議室
- 講演者
- 土屋智恵
- 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
10月16日（火）
- Campus
- Mitaka
- Seminar
- DTA colloquium
- Regularly Scheduled/Sporadic
- Regularly Scheduled
- Date and time
- Oct. 16, 2018, 14:30-15:30
- Place
- Lecture room
- Speaker
- Kazunari Iwasaki
- Affiliation
- Osaka University
- Title
- The formation of molecular clouds by compression of atomic gases
- Abstract
-
The formation of molecular clouds is one of the fundamental building blocks
in star formation. In order to determine the initial condition of the star formation,
it is crucial to reveal the formation and evolution processes of molecular clouds.
We investigate the formation of molecular clouds from atomic gas by using
three-dimensional magnetohydrodynamical simulations including non-equilibrium
chemical reactions and heating/cooling processes. We consider super-Alfvenic
head-on colliding flows of the atomic gas possessing the two-phase structure.
We examine how the molecular cloud formation changes depending on the angle
between the upstream flow and mean magnetic field. If the atomic gas is
compressed almost along the mean magnetic field, the accretion of the highly
inhomogeneous upstream atomic gas drives a super-Alfvenic velocity dispersion
which decreases the mean density of the post-shock layer. Even a small obliqueness
of the magnetic field weakens the post-shock turbulence. As a result, the post-shock
layer becomes denser than that formed by a colliding flow almost aligned to
the magnetic field. If the magnetic field is further inclined to the upstream flow,
the shock-amplified magnetic pressure suppresses gas compression,
leading to an extended post-shock layer. Our results, therefore, show that
there is a critical angle which maximizes the mean density of the post-shock layers.
Developing an analytic model and performing a parameter survey, we derive
an analytic formula of the critical angle as a function of the mean density,
collision speed, and field strength of the upstream atomic gas. We also found that
the dependence of the post-shock layers on the angle causes a diversity of
the physical properties of dense clumps. - Facilitator
- -Name：Tomoya Takiwaki
- Comment
- In English
10月17日（水）
- Campus
- Mitaka
- Seminar
- SOKENDAI colloquium
- Regularly Scheduled/Sporadic
- Regular
- Date and time
- October 17, 2018, 10:30 -12:00
- Place
- Lecture Room
- Speaker
- Satoshi Tanioka
- Affiliation
- SOKENDAI 3rd year (D1)(Supervisor: Yoichi Aso,R. Flaminio,T. Akutsu)
- Title
- Toward O3
- Abstract
- Advanced LIGO and Advanced VIRGO will start 3rd observing run from early 2019. KAGRA is trying to join this observing run. I will report on the current status of KAGRA.
Please note that the presenter information posted here is not necessarily listed in order of presentation.
- Facilitator
- -Name：Yoshiki Hatta
- Comment
- TV conference system is available connecting from Nobeyama, Hawaii, Mizusawa, and Okayama.