月別アーカイブ: 2017年12月

Chemically-old stars with young age estimates / 電波銀河の形成過程の解明

Speaker1
Tadafumi Matsuno, SOKENDAI 3rd year (D1)(Supervisor: Wako Aoki,Takuji Tsujimoto,Yutaka Komiyama)
Title
Chemically-old stars with young age estimates
Abstract
The combination of a large spectroscopic survey and asteroseismology has discovered a peculiar stellar population in the Galactic disk: they are estimated to be young from their masses but has similar alpha-elements abundances to old stars. Since their existence is not predicted in simple galactic chemical evolution models, the origin is yet to be explained. We obtained high-quality high-resolution optical spectra for 14 of such stars. In addition to the confirmation of their alpha-enhancements, we show that they follow the typical abundance pattern of old stars in almost all the measured elements. Together with the high frequency of radial velocity variation, we suggest they are results of stellar merger or mass transfer from red giants.

Speaker2
Takafumi Tsukui, SOKENDAI 1st year (M1)(Supervisor: 井口聖,永井洋,松田有一)
Title
電波銀河の形成過程の解明
Abstract
Please note that the presenter information posted here is not necessarily listed in order of presentation.

Resolved magnetic-field structure and variability near the event horizon of Sgr A* / Dynamics of jets/outflows from high-mass young stellar objects revealed by KaVA and ALMA observations / Lyman Alpha Imaging around a Hyperluminous QSO at z=2.84

[Speaker1]
Shuichiro Tsuda, SOKENDAI 1st year (M1)(Supervisor: 本間希樹,秦和弘,柴田克典)
[Title]
Resolved magnetic-field structure and variability near the event horizon of Sgr A*

[Speaker2]
Jungha Kim, SOKENDAI 4th year (D2)(Supervisor: 本間希樹,廣田智也,柴田克典)
[Title]
Dynamics of jets/outflows from high-mass young stellar objects revealed by KaVA and ALMA observations

[Speaker3]
Satoshi Kikuta, SOKENDAI 3rd year (D1)(Supervisor: Masatoshi Imanishi,Yuichi Matsuda,Yutaka Komiyama)
[Title]
Lyman Alpha Imaging around a Hyperluminous QSO at z=2.84
[Abstract]
Ly-alpha imaging is a powerful technique to study galaxy formation at high-redshift by detecting redshifted Ly-alpha emission line with narrowband filters. I present the latest results of our Ly-alpha imaging around a hyperluminous QSO at z=2.84, namely HS1549+1919, with HSC/Subaru. We have detected >3400 LAEs within 36 arcmin from the QSO (i.e., ~1.1 deg^2 FoV). The QSO is found to reside in the center of massive overdensity of LAEs which is embedded within a large scale (~100 cMpc) structure of LAEs. We have also detected a gigantic Ly-alpha nebula around the QSO as well as many Ly-alpha blobs. The nebula is the largest and the most luminous to date and has a peculiar morphology: bubble-like structure extending several hundred kpc. After sharing the current status I present our future plans to further reveal galaxy formation in this rich environment. Your comments and suggestions are very welcome.

Gravitational wave sensitivity enhancement via quantum noise reduction / Review of star formation, gas inflow and outflow from chemical evolution

[Speaker 1]
Zhao Yuhang, SOKENDAI 3rd year (D1)(Supervisor: Raffaele Flaminio,Matteo Leonardi,)
[Title]
Gravitational wave sensitivity enhancement via quantum noise reduction

[Speaker 2]
Nao Fukagawa, SOKENDAI 3rd year (D1)(Supervisor: Prof. Tadayuki Kodama,,)
[Title]
Review of star formation, gas inflow and outflow from chemical evolution