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# 2014.7.14-7.20

## 7月14日(月)

キャンパス

セミナー名

7月14日（月曜日）13時30分～15時

タイトル

Abstract

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

## 7月16日(水)

Campus
Mitaka
Seminar
SOKENDAI colloquium
Regular/Irregular
Regular
Date
10:00-12:00,　July 16, 2014
Place
Lecture Room
Speaker
Nagisa Shino
Affiliation
D3, SOKENDAI, Mitaka(supervisor: Mareki Honma)
Title
Investigating the formation scenario of a massive star forming region IRAS18089-1732 from molecular line spectra
Facilitator
-Name：Taiki Suzuki

## 7月16日(水)

キャンパス

セミナー名

定例

７月16日（水曜日）１４時１０分～１５時１０分

コスモス会館会議室

NAOJ
タイトル
Analytical computation of generalized Fermi-Dirac integrals by truncated Sommerfeld expansions
Abstract
For the generalized Fermi-Dirac integrals, $F_k(¥eta,¥beta)$, of orders $k=-$1/2, 1/2, 3/2, and 5/2, we explicitly obtained the first 11 terms of their Sommerfeld expansions. The main terms of the last three orders are rewritten so as to avoid the cancellation problem. If $\eta$ is not so small, say not less than 13.5, 12.0, 10.9, and 9.9 when $k=-1/2$, $1/2$, $3/2$, and $5/2$, respectively, the first 8 terms of the expansion assure the single precision accuracy for arbitrary value of $\beta$. Similarly, the 15-digits accuracy is achieved by the 11 terms expansion if $\eta$ is greater than 36.8, 31.6, 30.7, and 26.6 when $k=-1/2$, $1/2$, $3/2$, and $5/2$, respectively. Since the truncated expansions are analytically given in a closed form, their computational time is sufficiently small, say at most 4.9 and 6.7 times that of the integrand evaluation for the 8- and 11-terms expansions, respectively. When $\eta$ is larger than a certain threshold value as indicated, these appropriately-truncated Sommerfeld expansions provide a factor of 10-80 acceleration of the computation of the generalized Fermi-Dirac integrals when compared with the direct numerical quadrature.

名前：　藤井通子

## 7月18日(金)

キャンパス

セミナー名

7月18日(金) 16:00-17:00

Yoichi Aso

NAOJ
タイトル
“Opening a new window to the Universe with KAGRA: How do we do that ?”
Abstract
The second generation interferometric gravitational wave detectors, such as KAGRA, will start observations in the coming years. The unprecedented sensitivity of those detectors is likely to bring us multiple detection of gravitational wave events per year, opening a completely new window to observe the Universe for us. Direct detection of gravitational waves will provide us with rich and unique opportunities to explore physics of extreme conditions such as the test of general relativity under truly strong gravity fields, determination of the equation of state of neutron stars, observation of quasi-normal oscillations of black holes and so on. However, the technical challenges to detect a tiny deformation of the space-time as small as 10^-24 are enormous. In this talk, I will explain how we are trying to achieve such an incredible sensitivity and report the current status of the construction of KAGRA.

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