6月6日（月）13：30～15：00 太陽系小天体セミナー 南棟２階会議室
Jun 6 Mon Solar System Minor Body Seminar Conference Room, South Bldg.2F
6月8日（水）10:00～12:00 総研大コロキウム 中央棟（北）1F講義室
Jun 8 Wed SOKENDAI colloquium Lecture Room
6月8日（水）13：30～14：30 理論コロキウム コスモス会館会議室
Jun 8 Wed DTA colloquium Conference Room, Cosmos Lodge
6月9日（木）15：00～16：00 VLBIコロキウム 中央棟(南)2階VLBIセミナー室
Jun 9 Thu VLBI Colloquium VLBI Seminar Room, Main Bldg. (South) 2F
6月10日（金）13:30～15:00 太陽天体プラズマセミナー コスモス会館会議室
Jun 10 Fri Solar and Space Plasma Seminar Conference Room, Cosmos Lodge
6月10日（金）16：00～17：00 国立天文台談話会 大セミナー室
Jun 10 Fri NAOJ Seminar Large Seminar Room
詳細は以下をご覧下さい。
6月6日（月）
- 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
- 6月6日（月曜日）13時30分～15時
- 場所
- 南棟２階会議室
- 講演者
- 古荘玲子
- 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8日（水）
- Campus
- Mitaka
- Seminar
- SOKENDAI colloquium
- Regular / Irregular : Regular
- Place
- Lecture Room
- Speaker1
- Affiliation
- SOKENDAI
- Title
- TBD
- Speaker2
- Affiliation
- D2, SOKENDAI (Supervisor: Nobunari Kashikawa)
- Title
- Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs)
- Abstract
- I will present recent updates of high-redshift (z>6) quasar search project using Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) survey, with which we have succeeded in identifying 9 z>6 quasars from the initial data release. Also, I will show the result of another faint quasar search at z~6 using deep Subaru/Suprime-Cam images.
- Speaker3
- Affiliation
- M2, SOKENDAI (Supervisor: Wako Aoki)
- Title
- A Search for the Cause of Low Lithium Abundances in Some Extremely Metal-Poor Stars
- Facilitator
- Name : Kotomi Taniguchi
- Comment
-
TV conference system is available connecting from Nobeyama, Hawaii,
Mizusawa, and Okayama.
Date：10:00-12:00, June8, 2016
Taiki Suzuki
Masafusa Onoue
Tadafumi Matsuno
6月8日（水）
- Campus
- Mitaka
- Seminar
- DTA colloquium
- Regularly Scheduled/Sporadic
- Regularly Scheduled Date and time：8 June 2016, 13:30-14:30
- Place
- Conference Room, Cosmos Lodge
- Speaker
- Alessandro Sonnenfeld
- Affiliation
- IPMU
- Title
- Dark matter in early-type galaxies: a lensing view
- Abstract
- Dark matter halos play a crucial role in the formation and evolution of galaxies but observational constraints on the distribution of dark matter are currently very poor.Gravitational lensing is a very powerful tool for measuring galaxy masses at cosmological distances and provides a unique opportunity for probing the distribution of dark matter in the most massive galaxies. By statistically combining the lensing signal from a large set of galaxies we explored how the average dark matter distribution correlates with the properties of the baryonic component. Strong lensing constraints reveal an anticorrelation between galaxy size and dark matter mass enclosed within 5kpc. At larger scales, probed by weak lensing, we observe a positive correlation between halo mass and the velocity dispersion of the central galaxy, at fixed stellar mass. These results could have a significant impact on our understanding of the formation and evolution of massive galaxies.
- Facilitator
- -Name：Tomoya Takiwaki
- Comment
- in English
6月9日（木）
- キャンパス
- 三鷹
- セミナー名
- VLBIコロキウム
- 定例・臨時の別
- 定例
- 日時
- 6月9日（木曜日）15時～16時
- 場所
- 中央棟(南)2階VLBIセミナー室
- 講演者
- Daisuke Sakai
- 所属
- The University of Tokyo (Mizusawa VLBI Observatory)
- タイトル
- SgrB2M reference VLBI astrometry toward the Galactic center region with VERA
- Abstract
- VLBI astrometry toward the Galactic center direction is important because line-of-site velocity toward this direction degenerates into near zero, and it makes dynamical distance measurement difficult.
However, VLBI astrometry toward the Galactic center is difficult because of less number of position reference extragaractic source and large atmospheric scattering due to low elevation from north hemisphere. In such a case, we usually use strong target masers for fringe search, but the number of strong maser source is limited. We need other observation method to measure as many sources as possible.
To avoid these difficulties, we use a strong maser spot associated with Sgr B2M region as a reference source. By measuring relative position of target maser sources and position reference QSO relative to the strong maser source, we can measure absolute position of target maser source relative to QSO indirectly.
In this talk. I will show results and remaining problems by some observations to G359.93 and J17445. I will also present the progress of accuracy verification for this method. - 連絡先
- -名前：倉持一輝
- 備考
- 英語、テレビ参加可
6月10日（金）
- Campus
- Mitaka
- Seminar
- Solar and Space Plasma Seminar
- Regularly Scheduled/Sporadic
- Regular
- Date and time
- 10 June (Fri), 13:30-15:00
- Place
- Conference Room, Cosmos Lodge
- Speaker
- Anand D Joshi
- Affiliation
- NAOJ
- Title
- Quiescent Filament Eruption and Neighbouring Flares/Automated Detection and Tracking of Solar Filaments
- Abstract
-
Part 1: Quiescent Filament Eruption and Neighbouring Flares A large quiescent filament near the south-west limb of the Sun underwent an eruption on 14 August 2013. Shortly before the eruption, two flares occur in AR 11817, located near the filament. The apparent temporal proximity suggests that the flares caused the filament to erupt.
However, there is no extreme ultraviolet wave or ejection to support this. Upon closer inspection, the AIA 171 A images reveal oscillations in western portion of the quiescent filament almost 40 hours prior to eruption, but not in the eastern portion. For several hours prior to eruption, the western portion is seen to undergo a slow rise.
Subsequently it is this western portion which erupts, while the eastern portion does not. We suggest that the oscillations are a result of natural perturbation, and the flares acted as a destabilising factor which resulted in the eruption. The AR itself showed activity in the form of large shear and migration of polarity over two days. Results from the analysis of the filament and active region would be presented.Part 2: Automated Detection and Tracking of Solar Filaments A technique that automatically detects and tracks filaments on the Sun in full-disc Halpha images would be presented. The technique involves pre-processing and applying suitable intensity and size thresholds, after which filaments are extracted from the images. Every filament is labelled with a unique number for identification, and the labels can be followed through successive images, allowing us to detect the disappearance of filaments. Filament attributes such as their position on the solar disc, total area, length, are determined, with the aim to study its eruption. The processing time of the algorithm is small enough to allow real-time application. Challenges to apply this technique on AIA images and their possible solutions would also be discussed in brief.
- Facilitator
- -Name：Shin Toriumi
6月10日（金）
- キャンパス
- 三鷹
- セミナー名
- 国立天文台談話会
- 定例・臨時の別
- 定例
- 日時
- 6月10日（金） 16:00-17:00
- 場所
- 大セミナー室
- 講演者
- Roland Diehl
- 所属
- Max Planck Institut fur extraterrestrische Physik, TU Munchen, and Munich Excellence Cluster on Origin and Structure of the Universe
- タイトル
- ” Lessons from Cosmic Gamma-Ray Line Observations with INTEGRAL ”
- Abstract
- Gamma-ray lines from cosmic sources arise from radioactive decay of unstable isotopes co-produced by nucleosynthesis, from energetic collisions among atomic nuclei which may excite nuclei, and from interstellar annihilation of positrons ejected from a variety of candidate sources. ESA’s INTEGRAL space mission since its launch in 2002 measures such lines, thus complementing the earlier survey of NASA’s Compton Gamma-Ray Observatory with precision spectroscopy.
Nuclei are mainly 56Ni, 57Ni, 44Ti, 26Al, and 60Fe, each from their characteristic sources; also positron annihilation has been measured and mapped throughout the Galaxy both in the 511 keV line and positronium continuum. In this talk we will present the instrumental technique and the INTEGRAL mission, then discuss results, addressing astrophysics of supernova explosions, black hole accretion, transport of nucleosynthesis ejecta around massive star groups, and galactic structure & interstellar medium aspects. - 連絡先
- -名前： 阿久津 智忠