2012.2.27-3.4

2月27日（月）13:30～15:00　　　太陽系小天体セミナー　　　南棟 2F 会議室
Feb 27 Mon　Solar System Minor Body Seminar　Conference Room, 2F South Bldg.

2月29日（水）13:30～ 　　　理論コロキウム　　　コスモス会館会議室
Feb 29 Wed　　　Colloquium of Theoretical Astronomy Div.　　　Cosmos Lodge

2月29日（水）15:00～16:00　　　野辺山談話会　　　野辺山観測所　講義室1
Feb 29 Wed　　　Nobeyama NAOJ Seminar　　　Lecture Room 1, Nobeyama

3月 1日（木）15:30～16:30　　　野辺山談話会　　　野辺山観測所　輪講室
Mar 1 Thu 　　　Nobeyama NAOJ Seminar　　　Seminar Room, Nobeyama

3月 2日（金）16:00～17:00　　　天文台談話会　　　すばる棟 1F 大セミナー室
Mar 2 Fri 　　　NAOJ Seminar　　　Large Seminar Room, Subaru Bldg.

詳細は以下をご覧ください。

2月27日(月)

キャンパス
三鷹
セミナー名
太陽系小天体セミナー
臨時・定例の別
定例
日時
2月27日（月）13:30～15:00
場所
南棟2階会議室
講演者
Patryk Sofia Lykawka
所属
近畿大学
タイトル
トロヤ群、ハウメア族、奇妙な小天体などによる主な結果と外部太陽系への含意
Abstract
The dynamical and physical properties of small bodies can reveal important clues on the origin and evolution of the solar system. Here, I focus on the latest results from numerical simulations aiming to explain the origin and evolution of Trojan asteroids of the giant planets and collisional family fragments representative of the Haumea’s family in the trans-Neptunian belt. The results suggest all giant planets were able to capture and retain a significant population of Trojans from the primordial planetesimal disk. The bulk of captured objects decay over Gyr providing an important source of new objects on unstable orbits. Concerning collisional families, the fragments spread in wide regions of orbital elements (covering the currently known Haumea’s family) and displayed negligible variations. These objects also populated the four dynamical classes of TNOs. I will discuss the implications of these results for the formation and early evolution of the giant planets and small bodies in the trans-Neptunian belt.
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
Campus
Mitaka
Seminar
Solar System Minor Body Seminar
Regular/Irregular
Regular
Date
Febraury 27th 13:30～15:00
Place
the Conference Room of South Building (2F), NAOJ
Speaker
Patryk Sofia Lykawka
Affiliation
Kinki University
Title
Trojans, Haumea’s family TNOs and other peculiar small bodies:
main results and implications for the outer solar system
Abstract
The dynamical and physical properties of small bodies can reveal important clues on the origin and evolution of the solar system. Here, I focus on the latest results from numerical simulations aiming to explain the origin and evolution of Trojan asteroids of the giant planets and collisional family fragments representative of the Haumea’s family in the trans-Neptunian belt. The results suggest all giant planets were able to capture and retain a significant population of Trojans from the primordial planetesimal disk. The bulk of captured objects decay over Gyr providing an important source of new objects on unstable orbits. Concerning collisional families, the fragments spread in wide regions of orbital elements (covering the currently known Haumea’s family) and displayed negligible variations. These objects also populated the four dynamical classes of TNOs. I will discuss the implications of these results for the formation and early evolution of the giant planets and small bodies in the trans-Neptunian belt.
Facilitator
Name：Jun-ichi Watanabe
Comment
・welcome to participate via TV conference system or Skype system

2月29日(水)

キャンパス
三鷹
セミナー名
理論コロキウム
臨時・定例の別
定例
日時
2月29日（水）13:30～
場所
コスモス会館会議室
講演者
野村 英子氏
所属
京都大学
タイトル
Chemical structure and lines of molecules in protoplanetary disks
Abstract
Thanks to recent development of infrared and mm/submm observations, it has become possible to detect various kinds of molecular lines from protoplanetary disks. And now the ALMA Early Science has started and the forthcoming ALMA observations will reveal physical and chemical properties of planet-forming regions in the disks with its high spatial resolution and high sensitivity.　In this work we have studied the chemical structure of protoplanetary disks, using a comprehensive astrochemical reaction network together with detailed treatment of UV and X-ray irradiation from the central stars. I will introduce our recent works especially focusing on (i) effects of grain surface reactions on formation of complex molecules, (ii) effects of gas motion, such as turbulent mixing and gas accretion towards the central star, on infrared line emission, (iii) gas ionization degree to discuss magnetorotationally stable region, and (iv) submm molecular lines as a tool to measure gas temperature gradient in the disk surface using the ALMA observations, and its relation to photoevaporation of the gas.
連絡先
名前：山崎 大
キャンパス
野辺山
セミナー名
国立天文台野辺山　談話会
臨時・定例の別
臨時
日時
2月29日（水）15:00～16:00
場所
野辺山宇宙電波観測所　講義室1
講演者
高野秀路
所属
国立天文台野辺山
タイトル
Welkom! Our research in Leiden, The Netherlands
Abstract
– Detection of Methyl Formate in the Second Torsionally Excited State in Orion KL Recent progress on microwave spectroscopy of methyl formate in laboratory and sensitive radioastronomical observations made it possible to assign about 20 emission lines to methyl formate in this state.
The beam-averaged column density obtained is (3.0 +- 1.5) x 10^{14} cm^{-2}.
We discuss the excitation mechanism to the torsional states.
This detection further indicates that many more unidentified lines in Orion KL could be due to low-lying excited states of methyl formate and other organic molecules.
– Detection of Ammonia in M51
To study the abundance and temperature of ammonia in the center of a nearby galaxy M 51 and to compare them with those in other nearby galaxies, we observed its (J,K) = (1,1), (2,2), (3,3), and (4,4) inversion transitions at the wavelength of 1.3 cm. The observations were carried out with the Effelsberg 100 m telescope in 2000 and 2002.
As a result, the (1,1), (2,2), and (3,3) transitions are clearly detected.
The temperature obtained is 25+-2 K, which is similar to those of NGC 253 and M 82.
The column density of ammonia is (8.1 +- 2.4) x 10^{13} cm^{-2}, and the abundance relative to H2 is about 4 x 10^{-9}.
The abundance in M 51 is about a factor of 5 lower than those of NGC 253 and IC 342, but about one order of magnitude higher than those of M 82 and the Large Magellanic Cloud (N 159 W).
For understanding the abundance of ammonia, its photodissociation rate was compared to those of related molecules detected in the nearby galaxies.
連絡先
名前：小野寺幸子

3月1日(木)

キャンパス
野辺山
セミナー名
国立天文台野辺山　談話会
臨時・定例の別
臨時
日時
3月1日（木）15:30～16:30
場所
野辺山宇宙電波観測所　輪講室
講演者
Timothy Davis
所属
ESO
タイトル
Red but not dead! Molecular gas in early-type galaxies
連絡先
名前：小野寺幸子

3月2日(金)

キャンパス
三鷹
セミナー名
国立天文台談話会
臨時・定例の別
定例
日時
3月2日（金）16:00～17:00
場所
大セミナー室
講演者
藤本眞克
所属
国立天文台重力波プロジェクト推進室
タイトル
重力波探究の40年
アブストラクト
我が国の重力波研究者の悲願であった大型低温重力波望遠鏡（愛称KAGRA）の建設が始まった。KAGRAは神岡鉱山の岩盤内に設置する基線長3kmで20Kに冷却されたミラーから構成されるレーザー干渉計で、8億光年の距離で発生する連星中性子星の衝突・合体からの重力波を検出できる感度を持つ計画であり、1年間の観測で数回以上の重力波検出が期待できる装置である。アインシュタインが一般相対論によって1世紀近く前に予言した重力波の検出が研究者の間で真剣に考えられるようになったのは1969年のJ. Weberによる発見の発表からである。当時大学4年生であった私はそれから40年を超える期間、重力波検出の研究に関わることになった。我が国の重力波探究の歴史を一研究者の個人的な経験から振り返ってみたい。
連絡先
名前：勝川行雄

以上