6月15日（月）13:30～15:00 太陽系小天体セミナー 南棟2F 会議室
Jun 15 Mon Solar System Minor Body Seminar Conference Room, South Bldg. 2F
6月17日（水）10:30～12:00 総研大コロキウム 中央棟（北）1F 講義室
Jun 17 Wed SOKENDAI Colloquium Lecture Room
6月17日（水）13:30～15:30 理論コロキウム コスモス会館会議室
Jun 17 Wed DTA Colloquium Conference Room, Cosmos Lodge
6月17日（水）15:00～16:00 国立天文台野辺山談話会 野辺山宇宙電波観測所
Jun 17 Wed Nobeyama NAOJ Seminar Seminar Room, Main building, NRO
6月18日（木）15:00～16:00 VLBIコロキウム 中央棟（南）2F VLBIセミナー室
Jun 18 Thu VLBI Colloquium VLBI Seminar Room, Main Bldg. (South) 2F
6月19日（金）16:00～17:00 国立天文台談話会 大セミナー室
Jun 19 Fri NAOJ Seminar Large Seminar Room
詳細は以下をご覧下さい。
6月15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
- 6月15日（月）13:30～15:00
- 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
6月17日(水)
- Campus
- Mitaka
- Seminar Name
- SOKENDAI colloquium
- Regular/Irregular
- Regular
- Date
- 10:30-12:00, Jun. 17, 2015
- Place
- Lecture Room
- Speaker
- Ryosuke Nagasawa
- Affiliation
- Title
- Construction of high-precision lunar ephemeris using LLR data fitting
- Organizer
- Name : Tsuguru Ryu
- Comment
- TV conference system is available connecting from Nobeyama, Hawaii, Mizusawa, and Okayama
D1, SOKENDAI, Mitaka (supervisor : Hideo Hanada)
6月17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
- 6月17日（水）13:30～15:30
- 場所
- コスモス会館会議室
- 講演者
- Lukasz Stawarz
- 所属
- ISAS, Japan / Jagiellonian University, Poland
- タイトル
- Particle Acceleration in Astrophysical Sources of High Energy Radiation
- Abstract
- Strong shocks induced in the interstellar medium by supernova explosions are widely considered as the dominant production sites of cosmic ray particle detected on Earth with enormous energies reaching 10^15 eV. Relativistic, or instead weak by extremely extended shock waves encountered in various types of extragalactic object – predominantly active galaxies and clusters of galaxies – are on the other hand typically considered as the most likely sources of even higher energy cosmic rays, up to the ultra-high energy range of 10^21 eV. In this talk I will critically re-examine the current status of our understanding of particle acceleration in astrophysical environment in general, pointing out the most recent observational findings which challenge the shock paradigm for the cosmic ray production, and emphasizing important but often ignored differences between particle acceleration processes in non-relativistic and relativistic plasma.
- 講演者
- 紀 基樹
- 所属
- KASI, Korea
- タイトル
- On the origin of black hole outflows
- Abstract
- Understanding formation mechanism of relativistic jets in active galactic nuclei (AGN) is one of the biggest issues in astrophysics. To solve the problem, outstanding question is basic energetics in the vicinity of the central black holes which ultimately power the relativistic jets. The AGN jet Messier 87 (hereafter M87) is one of the closest (16Mpc from the Earth) example of relativistic jets and it is well known as the best source to explore a jet base close to ~10 Schwarzschild radii scale with VLBI (Very Long Baseline Interferometry) radio telescopes. Here I show highlights of VLBI observations of innermost part of the M87 jet. Then, I show the results of our estimate of magnetization degree at the base of M87 down to ISCO (innermost stable circular orbit) scale based on these observational data.
- 連絡先
- 名前：銭谷 誠司
6月17日(水)
- 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
- 定例
- 日時
- 6月17日（水）15:00～16:00
- 場所
- 野辺山宇宙電波観測所 本館 輪講室
- 講演者
- 金子紘之 氏
- 所属
- 国立天文台 野辺山宇宙電波観測所
- タイトル
- 相互作用銀河VV 219の分子ガスの物理性質
- Abstract
- 前半では、先月末にギリシャで行われた国際研究会”Gas, Dust & Star Formation in Galaxies from the Local to Far Universe” の報告を行う。後半では、この研究会で発表した相互作用銀河の分子ガスの物理性質について取り上げる。銀河の衝突現象は、不変的にみられる現象であり、銀河の進化史においても非常に大きな役割を果たすことが知られている。銀河衝突で起こされる重要な特質の一つに、星形成活動の活発化があるが、1980年代から知られているにもかかわらず、星形成の原料である分子ガスの観測の不十分さからその原因についてはまだ解明されていない。本発表ではALMA Cycle 1のデータによる相互作用銀河VV 219での銀河衝突領域での分子ガスに見られた特徴的構造と、これを踏まえた今後の研究についても紹介したい。
- 連絡先
- 名前：宮本祐介
- 備考
- テレビ参加可
6月18日(木)
- キャンパス
- 三鷹
- セミナー名
- VLBIコロキウム
- 臨時・定例の別
- 定例
- 日時
- 6月18日（木）15:00～16:00
- 場所
- 中央棟(南)2階VLBIセミナー室
- 講演者
- Kazunori Akiyama
- 所属
- NAOJ Mizusawa VLBI Observatory
- タイトル
- Review: new insights into the scattering medium around the galactic supermassive black hole Sgr A*
- Abstract
-
The presence of the turbulent interstellar plasma has been preventing us from observing the fine-scale structure of the galactic center Sgr A* associated with the supermassive black hole with the largest angular size. The tenuous interstellar plasma scatters the radio wave from Sgr A*, and then blurs the image of Sgr A*. This effect decreases steeply with increasing frequency and becomes subdominant to the intrinsic emission structure at wavelengths close to a millimeter.
At 1.3 mm, the angular broadening effect is subdominant but still not negligible. However, the recent work demonstrates we can reconstruct the unscattered image of Sgr A* with 1.3-mm observation with Event Horizon Telesope (EHT) when properties of the scattering are known (Fish et al. 2014).
In addition, despite decades of study, there has been many progresses in understanding the scattering properties including studies of the magneter very close to Sgr A* (e.g. Bower et al. 2014, 2015) and discovery of refractive substructure in the scattering disk of Sgr A* at 22 GHz (Gwinn et al. 2014) in recent couple of years.
In this talk, I will review some basics of the interstellar scattering, recent works (Bower et al. 2014, 2015, Fish et al. 2014, Gwinn et al. 2014, Johnson & Gwinn 2015, etc) related with the interstellar scattering effect on Sgr A* and discuss their implications for imaging Sgr A* with the EHT and possible future science cases for high sensitivity Sgr A* observations with KaVA. - 連絡先
- 名前：酒井 大裕
- 備考
- テレビ参加可
6月19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
- 6月19日(金) 16:00-17:00
- 場所
- 大セミナー室
- 講演者
- Karl M. Menten
- 所属
- Max-Planck-Institut for Radio Astronomy
- タイトル
- A Global View of Star Formation in the Milky Way
- Abstract
- Stars with more than about ten solar masses dominate galactic ecosystems. Understanding their formation is one of the great challenges of modern astronomy. The spectacular HII regions they excite delineate the spiral arms of galaxies such as our own when seen face on ? making it clear that star formation and Galactic structure are intimately related. We report on an ambitious program that consists of a powerful multi-pronged approach to study star formation over the whole Milky Way. Using VLBI observations of maser sources associated with young protostars, we are measuring distances by trigonometric parallax to most of the dominant star forming regions in the Galaxy, which reveal its spiral structure and yield improved values of the rotation parameters and are crucial for determinations of luminosities and masses. Submillimeter emission from dust mapped by ATLASGAL, the APEX Telescope Large Area Survey of the Galaxy, delivers the locations of deeply embedded protostars and protoclusters and their masses. In a comprehensive follow-up program we are studying the state of excitation, chemistry and kinematics of their gaseous content. At longer, radio wavelengths, in a very sensitive survey with the newly expanded Karl G. Jansky Very Large Array (JVLA) we find and image masers and hyper- and ultracompact HII regions, pinpointing the very centers of the earliest star-forming activity. We are also studying the infrared emission from more developed massive star clusters, deriving distances with the classic spectro-photometric method for the first time adapted to an extensive IR dataset and properly calibrated with trigonometric parallaxes. Our synoptic approach is using the world’s premier observatories to create a coherent, unique dataset with true legacy value for a global perspective on star formation in our Galaxy.
- 連絡先
- 名前：松田 有一
以上