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# 2017.10.23-10.29

## 10月24日（火）

キャンパス

セミナー名

10月24日（火曜日）13時30分～15時

名前：渡部潤一

テレビ会議またはスカイプによる参加も可

## 10月25日（水）

Campus
Mitaka
Seminar
SOKENDAI colloquium
Regular
Date and time
October 25, 2017, 10:30 -12:00

Place
Lecture Room

Speaker1
Hisakazu Uchiyama
Affiliation
SOKENDAI: D3 (Supervisor : Nobunari Kashikawa, Yuichi Matsuda, Yutaka Komiyama)
Title
Systematic Study of QSO Radiative Feedback in High-z Universe

Speaker2
Masaki Yoshida
Affiliation
SOKENDAI: D1 (Supervisor :Y. Suematsu, H. Hara, R. Ishikawa)
Title
Wave Propagation along Spicules Observed by Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP)

Facilitator
-Name：Nagaaki Kambara

Comment
TV conference system is available connecting from Nobeyama, Hawaii, Mizusawa, and Okayama.

## 10月25日（水）

Campus
Mitaka
Seminar
DTA colloquium
Regularly Scheduled
Date and time
Oct. 25 2017, 13:30-14:30
Place
Conference Room, Cosmos Lodge
Speaker
Sho Fujibayashi
Affiliation
Kyoto University
Title
The evolution and mass ejection from the remnant of the binary neutron star merger
Abstract
We perform general relativistic, long-term, axisymmetric neutrino radiation hydrodynamics simulations for a remnant massive neutron star (MNS) surrounded by a torus, which is a canonical remnant formed after the binary neutron star merger. In this work, we take into account effects of viscosity which is likely to arise in the merger remnant due to magnetohydrodynamical turbulence. We find that two viscous effects play a key role for the evolution of the remnant system and resulting mass ejection. In the first ~10 ms, the structure of the MNS is changed due to the viscous angular momentum transport. As a result, a sound wave, which subsequently becomes a shock wave, is formed in the vicinity of the MNS and the shock wave leads to significant mass ejection. For the longer-term evolution with ~ 0.1–10 s, viscous effects on the torus surrounding the MNS play an important role for mass ejection. The mass ejection rate depends on the viscous parameter for both mass ejection mechanisms, but even for the conservative alpha viscous parameter $\alpha_{\rm vis}\sim0.01$, total ejecta mass is $\sim 5\times 10^{-3}\ M_\odot$ and for $\alpha_{\rm vis}\sim0.04$, it could be $0.02\ M_\odot$. In this talk, I will explain the viscosity-driven mass ejection processes and discuss the electromagnetic signal from the ejecta.
Facilitator
-Name：Tomoya Takiwaki

Comment
in English

## 10月27日（金）

キャンパス

セミナー名

10月27日（金曜日）10:30～12:00

ALMA棟102室

タイトル
すばる望遠鏡に見られるTerrestrial dustについて

-名前：大宮正士・石川裕之

ZOOM、TV会議システムでの参加も可能です。

## 10月27日（金）

Campus
Mitaka
Seminar
Solar and Space Plasma Seminar
Regular
Date and time
27 October (Fri), 13:30-15:00
Place
Student Seminar Room, Subaru Bldg.
Speaker
Motoshi Goto
Affiliation
National Institute for Fusion Science
Title
Polarization spectroscopy for a study of anisotropic electron velocity distribution function in fusion plasma
Abstract
Excited states of atoms or ions in fusion plasma are dominantly created by electron collisions. When electrons in a plasma have an anisotropic velocity distribution function, excited states can have an inhomogeneous population distribution over the magnetic sublevels. Emission lines accompanying radiative transitions from such inhomogeneous states are generally polarized.In the Large Helical Device (LHD) at National Institute for Fusion Science, we have incorporated the same optical components as those used for CLASP into an existing normal incidence spectrometer and have started a polarization measurement for the Lyman-α line at 121.56nm.Initial results show that the polarization degree, which is in the order of several percent, has a tendency to decay as the electron density is increased. This behavior qualitatively agrees with our prediction because collisional relaxation processes become more effective and the anisotropy in the electron velocity distribution function should be more relaxed in a higher density condition.A summary of the obtained measurement results and the concept of a theoretical model to be used for the data analysis are introduced at the seminar.

Facilitator
-Name：Shin Toriumi

## 10月27日（金）

キャンパス

セミナー名

10月27日（金）　15:00-16:00

Juergen Stutzki

Universitat zu Koln
タイトル
CCAT-prime: a fast submm telescope for large area surveys
Abstract
CCAT-prime is a 6-meter diameter telescope located at 5600 meters elevation on Cerro Chajnantor in the high Atacama Desert of northern Chile, near the site of the TAO infrared telescope. Situated at a high, dry site and with a surface accuracy of better than 10 μm, CCAT-p will observe the sky at submillimeter to millimeter wavelengths. The novel ”crossed-Dragone” optical design delivers a high-throughput, wide-field-of-view telescope capable of illuminating more than 100,000 detectors, thus enabling rapid mapping of large areas of the sky. The high site offers superb observing conditions, yielding routine access to the 350 μm window. Deployment of the CCAT-p telescope and instrumentation on Cerro Chajnantor will provide operational experience at high altitude, reducing risk for the future construction of a 25-meter class telescope at the same site. A partnership between Cornell University, a consortium of German institutions led by Universitat zu Koln, and a consortium of eight Canadian academic institutions are working together to create CCAT-prime. Researchers at additional institutes in the U.S., Canada, Germany and Chile are involved in science planning and instrument development.

-名前：松田　有一

## 10月27日（金）

キャンパス

セミナー名

10月27日（金）　16:00-17:00

タイトル

Abstract

-名前：松田　有一

Home > Solar and Space Plasma (SSP) Seminar | 国立天文台談話会 | 太陽系小天体セミナー | 総研大コロキウム | 赤外ゼミ > 2017.10.23-10.29