The first chemo-dynamical view of very metal-poor stars / Lyman alpha imaging around a hyperluminous QSO at z=2.84 with HSC

[Speaker1]
Tadafumi Matsuno, SOKENDAI 4th year (D2)(Supervisor: Wako Aoki,Yutaka Komiyama,Takuji Tsujimoto)

[Title]
The first chemo-dynamical view of very metal-poor stars

[Abstract]
The second data release of Gaia (Gaia DR2) enables us to explore motions of a large number of stars in the Milky Way. Maximum scientific output would be obtained by complimenting the Gaia data set with stellar chemical abundances, since stellar motions tell us about past dynamical interactions between Milky Way and satellite galaxies whereas chemical abundances tell us about past star formation activities. To understand the formation history of the Galactic stellar halo, one of the oldest structures in the Milky Way, we have crossmatched the SAGA database, which complies results of abundance measurements for very metal-poor stars in literatures, to the Gaia DR2 catalog. In this talk, after describing the procedure of the crossmatch, I will introduce the latest results from the first chemo-dynamical analysis of very metal-poor stars.

[Speaker2]
Satoshi Kikuta, SOKENDAI 4th year (D2)(Supervisor: Masa Imanishi,Yuichi Matsuda,Yutaka Komiyama)

[Title]
Lyman alpha imaging around a hyperluminous QSO at z=2.84 with HSC

[Abstract]
We present the results of our Lyα imaging around a hyperluminous QSO, HS1549+1919, at z=2.84 with Hyper Suprime-Cam (HSC). Thanks to the HSC’s overwhelmingly large FoV, we detected >3000 Lyα emitters (LAEs) in diverse environments within a 1.1 deg^2 FoV. The QSO is confirmed to reside in the very center of a protocluster and is surrounded by a ~1pMpc-scale diffuse Lyα nebula. The EW distribution and properties of Lyα halos are studied as a function of environments. At the center, extreme objects such as QSOs, LABs, and SMGs are far more abundant than fields, suggesting a large amount of gas is accreting towards the center.

Search for massive overdensities at z~2.2 with Subaru HSC / Wave-front error measurements and optical alignment of CLASP2 telescope

[Speaker1]
Yongming Liang, SOKENDAI 1st year (M1)(Supervisor: Nobunari Kashikawa (U.Tokyo),Masayuki Tanaka,Yuichi Matsuda)
[Title]
Search for massive overdensities at z~2.2 with Subaru HSC

[Speaker2]
Masaki Yoshida, SOKENDAI 4th year (D2)(Supervisor: Yoshinori Suematsu,Hirohisa Hara,Ryohko Ishikawa)
[Title]
Wave-front error measurements and optical alignment of CLASP2 telescope

2018 国立天文台特別公開講座/総研大入試ガイダンス(関東会場)

 2018年5月19日(土)、国立天文台三鷹キャンパスにおいて、特別公開講演および総研大入試ガイダンスが行われました。本年も学部1年生の方から大学院生まで、総勢54名の方々にご来場いただきました。

 今年度は『国立天文台における天文学研究の最前線』テーマに、片岡章雅助教、田中賢幸准教教、大石雅寿准教授、松本晃治准教授の4名の先生方から、それぞれの分野の視点に立った興味深いご講演をいただきました。今年度は大学1年生の参加者が例年に比べ多く、大学に入ったばかりにもかかわらず、大学院へ進学することを考えている意識の高さに感心しました。講演の後の質問の時間には、一般的な天文学に関するものから非常に専門性の高いものまで、多くの質問がありました。
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2018 国立天文台特別公開講座/総研大入試ガイダンス(関西会場)

 2018年5月12日(土)、メルパルク京都で行われた国立天文台特別公開講座/総研大天文科学専攻入試ガイダンスには、14名の方々にご来場いただきました。“国立天文台における天文学研究の最前線”というテーマのもと、今西 昌俊 助教(ハワイ観測所)、松田 有一 助教(チリ観測所)、宮﨑 聡 准教授(先端技術センター)、林 左絵子 准教授(TMT推進室)の4名の講師による講演が行われました。
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bKAGRA Phase 1 From Kamioka with Love / status of the frequency dependent squeezing experiment at TAMA

[Speaker1]
Satoshi Tanioka, SOKENDAI 3rd year (D1)(Supervisor: Yoichi Aso,Ryutaro Takahashi,Tomotada Akutsu)
[Title]
bKAGRA Phase 1 From Kamioka with Love
[Abstract]
bKAGRA Phase 1 operation was held in April 28th to May 6th. I will report the overview.

[Speaker2]
zhao yuhang, SOKENDAI 3rd year (D1)(Supervisor: Matteo Leonardi,,)
[Title]
status of the frequency dependent squeezing experiment at TAMA
[Abstract]
It is expected that the second-generation gravitational wave detectors will be quantum noise limited in the whole detection frequency band. This expectation was partially confirmed by the LIGO-Virgo O1 and O2 runs. KAGRA will be the first 2.5-generation GW detector, and the quantum noise limit is expected to be even more severe than the second-generation detectors. The implement of frequency dependent squeezed(FDS) light source is one of the most promising solutions to this problem. After several years of table top experiments and proof of principle experiments, the implement of squeezing into GW detector is a mature technique. The most studied solution to realize an FDS is the coupling between a frequency independent squeezer to a Fabry-Perot cavity(usually addressed as filter cavity). One of the main parameter of this kind of experiment is the intra-cavity losses per meter of the filter cavity. One solution to mitigate this problem is to use hundred-meter scale filter cavity.

The purpose of our experiment, that is in the TAMA300 facility, is to realize FDS with a 300m long filter cavity. The filter cavity is hosted in an arm of the former TAMA300 interferometer. As of today, the filter cavity has been installed and is locked stably with a green field. The characterization work of the filter cavity is ongoing but almost finished. The assembling of the frequency independent squeezer is on going. The next step will be the characterization of the frequency independent squeezing and its injection into the filter cavity.