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204. Influence of body fat in cancer patients on residual content of used fentanyl matrix patches

Author

Chiba, Takeshi, primary, Kimura, Yusuke, additional, Takahashi, Hiroaki, additional, Tairabune, Tomohiko, additional, Nagasawa, Yoshiaki, additional, Mori, Kaoru, additional, Yonezawa, Yuji, additional, Sugawara, Atsuko, additional, Kawaguchi, Sachiko, additional, Kawamura, Hidenobu, additional, Nishizuka, Satoshi, additional, Kudo, Kenzo, additional, Fujiwara, Kunihiko, additional, Ikeda, Kenichiro, additional, Wakabayashi, Go, additional, and Takahashi, Katsuo, additional

Published
2010
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205. Observational Consequences of Evolution of Primordial Fluctuations in Scalar-Tensor Cosmology

Author

Nagata, Ryo, Chiba, Takeshi, Sugiyama, Naoshi, Nagata, Ryo, Chiba, Takeshi, and Sugiyama, Naoshi

Abstract

Evolution of primordial fluctuations in a Brans-Dicke type scalar-tensor gravity theory is comprehensively investigated. The harmonic attractor model, in which the scalar field has its harmonic effective potential in the Einstein conformal frame and the theory relaxes toward Einstein gravity with time, is considered. The evolution of adiabatic initial perturbations in flat SCDM models is examined from the radiation-dominated epoch up to the present. We discuss how the scalar-tensor gravity affects the evolution of metric and matter perturbations, mainly focusing on the observational consequences, i.e., the matter power spectrum and the power spectrum of cosmic microwave background temperature. We find that the early time deviation is characterized only by the large static gravitational constant while the late time behavior is qualitatively different from that in Einstein gravity because the time variation of the gravitational constant and its fluctuation have non-negligible effects. The attracting scalar-tensor gravity affects only small scale modes due to its attracting nature, the degree of which is far beyond the post-Newtonian deviation at the present epoch., Comment: 18 pages

Published
2002
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206. Tracking K-essence

Author

Chiba, Takeshi and Chiba, Takeshi

Abstract

We derive a condition for converging a common evolutionary track for k-essence (a scalar field dark energy with non-canonical kinetic terms). For the Lagrangian density V(phi)W(X) with X=dot{phi}^2/2, we find tracker solutions with w_{phi} < w_B exist if Gamma equivalent V''V/(V')^2 > 3/2. Here w_{phi}(w_B) is the equation-of-state of the scalar field (background radiation/matter). Our condition may be useful for examining the existence of the attractor-like behavior in cosmology with k-essence., Comment: 7 pages, minor changes, to appear in Phys.Rev.D

Published
2002
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207. The Japanese space gravitational wave antenna: DECIGO

Author

Chen, Dan, Hong, Feng-Lei, Ichiki, Kiyotomo, Ikegami, Takeshi, Inoue, Kaiki T., Ishidoshiro, Koji, Ishihara, Hideki, Ishizaki, Hideharu, Ito, Hiroyuki, Itoh, Yousuke, Izumi, Kiwamu, Kawashima, Nobuki, Kawazoe, Fumiko, Kishimoto, Naoko, Kiuchi, Kenta, Kobayashi, Shiho, Kohri, Kazunori, Kojima, Yasufumi, Kokeyama, Keiko, Kokuyama, Wataru, Kotake, Kei, Kozai, Yoshihide, Kunimori, Hiroo, Kuroda, Kazuaki, Kuroyanagi, Sachiko, Maeda, Kei-ichi, Matsumoto, Nobuyuki, Michimura, Yuta, Miyakawa, Osamu, Miyamoto, Umpei, Miyoki, Shinji, Morisawa, Toshiyuki, Moriwaki, Shigenori, Mukohyama, Shinji, Musha, Mitsuru, Nagano, Shigeo, Naito, Isao, Nakamura, Kouji, Nakano, Hiroyuki, Nakao, Kenichi, Nakasuka, Shinichi, Nakayama, Yoshinori, Nakazawa, Kazuhiro, Nishida, Erina, Nishizawa, Atsushi, Niwa, Yoshito, Noumi, Taiga, Obuchi, Yoshiyuki, Ohashi, Masatake, Ohishi, Naoko, Ohkawa, Masashi, Okada, Kenshi, Okada, Norio, Oohara, Kenichi, Sago, Norichika, Saijo, Motoyuki, Saito, Ryo, Sakagami, Masaaki, Sakata, Shihori, Sasaki, Misao, Sato, Takashi, Shibata, Masaru, Shinkai, Hisaaki, Shoda, Ayaka, Somiya, Kentaro, Sotani, Hajime, Sugiyama, Naoshi, Suwa, Yudai, Suzuki, Rieko, Tagoshi, Hideyuki, Takahashi, Fuminobu, Takahashi, Kakeru, Takahashi, Keitaro, Takahashi, Ryutaro, Takahashi, Ryuichi, Takahashi, Hirotaka, Akiteru, Takamori, Takano, Tadashi, Tanaka, Nobuyuki, Taniguchi, Keisuke, Taruya, Atsushi, Tashiro, Hiroyuki, Torii, Yasuo, Toyoshima, Morio, Tsujikawa, Shinji, Tsunesada, Yoshiki, Ueda, Akitoshi, Ueda, Ken-ichi, Wakabayashi, Yaka, Yagi, Kent, Yamakawa, Hiroshi, Yamamoto, Kazuhiro, Yamazaki, Toshitaka, Yoo, Chul-Moon, Yoshida, Shijun, Yoshino, Taizoh, Sun, Ke-Xun, Kawamura, Seiji, Ando, Masaki, Seto, Naoki, Sato, Shuichi, Nakamura, Takashi, Tsubono, Kimio, Kanda, Nobuyuki, Tanaka, Takahiro, Yokoyama, Jun'ichi, Funaki, Ikkoh, Numata, Kenji, Ioka, Kunihito, Takashima, Takeshi, Agatsuma, Kazuhiro, Akutsu, Tomotada, Aoyanagi, Koh-suke, Arai, Koji, Araya, Akito, Asada, Hideki, Aso, Yoichi, Chiba, Takeshi, Ebisuzaki, Toshikazu, Ejiri, Yumiko, Enoki, Motohiro, Eriguchi, Yoshiharu, Fujimoto, Masa-Katsu, Fujita, Ryuichi, Fukushima, Mitsuhiro, Futamase, Toshifumi, Harada, Tomohiro, Hashimoto, Tatsuaki, Hayama, Kazuhiro, Hikida, Wataru, Himemoto, Yoshiaki, Hirabayashi, Hisashi, Hiramatsu, Takashi, Horisawa, Hideyuki, Hosokawa, Mizuhiko, Ishikawa, Takehiko, Kawano, Isao, Koizumi, Hiroyuki, Kuninaka, Hitoshi, Matsuhara, Hideo, Morimoto, Mutsuko Y., Nishiyama, Kazutaka, Sakai, Shin-ichiro, Takahashi, Tadayuki, and Utashima, Masayoshi

Subjects
Physics, Optics, Physics and Astronomy (miscellaneous), Gravitational wave, business.industry, Big Bang Observer, Antenna (radio), Space (mathematics), business
Abstract

著者人数: 145名, 資料番号: SA1002921000

Published
2011
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213. DECIGO: The Japanese space gravitational wave antenna

Author

Sato, Shuichi, primary, Kawamura, Seiji, additional, Ando, Masaki, additional, Nakamura, Takashi, additional, Tsubono, Kimio, additional, Araya, Akito, additional, Funaki, Ikkoh, additional, Ioka, Kunihito, additional, Kanda, Nobuyuki, additional, Moriwaki, Shigenori, additional, Musha, Mitsuru, additional, Nakazawa, Kazuhiro, additional, Numata, Kenji, additional, Sakai, Shin-ichiro, additional, Seto, Naoki, additional, Takashima, Takeshi, additional, Tanaka, Takahiro, additional, Agatsuma, Kazuhiro, additional, Aoyanagi, Koh-suke, additional, Arai, Koji, additional, Asada, Hideki, additional, Aso, Yoichi, additional, Chiba, Takeshi, additional, Ebisuzaki, Toshikazu, additional, Ejiri, Yumiko, additional, Enoki, Motohiro, additional, Eriguchi, Yoshiharu, additional, Fujimoto, Masa-Katsu, additional, Fujita, Ryuichi, additional, Fukushima, Mitsuhiro, additional, Futamase, Toshifumi, additional, Ganzu, Katsuhiko, additional, Harada, Tomohiro, additional, Hashimoto, Tatsuaki, additional, Hayama, Kazuhiro, additional, Hikida, Wataru, additional, Himemoto, Yoshiaki, additional, Hirabayashi, Hisashi, additional, Hiramatsu, Takashi, additional, Hong, Feng-Lei, additional, Horisawa, Hideyuki, additional, Hosokawa, Mizuhiko, additional, Ichiki, Kiyotomo, additional, Ikegami, Takeshi, additional, Inoue, Kaiki T, additional, Ishidoshiro, Koji, additional, Ishihara, Hideki, additional, Ishikawa, Takehiko, additional, Ishizaki, Hideharu, additional, Ito, Hiroyuki, additional, Itoh, Yousuke, additional, Kawashima, Nobuki, additional, Kawazoe, Fumiko, additional, Kishimoto, Naoko, additional, Kiuchi, Kenta, additional, Kobayashi, Shiho, additional, Kohri, Kazunori, additional, Koizumi, Hiroyuki, additional, Kojima, Yasufumi, additional, Kokeyama, Keiko, additional, Kokuyama, Wataru, additional, Kotake, Kei, additional, Kozai, Yoshihide, additional, Kudoh, Hideaki, additional, Kunimori, Hiroo, additional, Kuninaka, Hitoshi, additional, Kuroda, Kazuaki, additional, Maeda, Kei-ichi, additional, Matsuhara, Hideo, additional, Mino, Yasushi, additional, Miyakawa, Osamu, additional, Miyoki, Shinji, additional, Morimoto, Mutsuko Y, additional, Morioka, Tomoko, additional, Morisawa, Toshiyuki, additional, Mukohyama, Shinji, additional, Nagano, Shigeo, additional, Naito, Isao, additional, Nakamura, Kouji, additional, Nakano, Hiroyuki, additional, Nakao, Kenichi, additional, Nakasuka, Shinichi, additional, Nakayama, Yoshinori, additional, Nishida, Erina, additional, Nishiyama, Kazutaka, additional, Nishizawa, Atsushi, additional, Niwa, Yoshito, additional, Noumi, Taiga, additional, Obuchi, Yoshiyuki, additional, Ohashi, Masatake, additional, Ohishi, Naoko, additional, Ohkawa, Masashi, additional, Okada, Norio, additional, Onozato, Kouji, additional, Oohara, Kenichi, additional, Sago, Norichika, additional, Saijo, Motoyuki, additional, Sakagami, Masaaki, additional, Sakata, Shihori, additional, Sasaki, Misao, additional, Sato, Takashi, additional, Shibata, Masaru, additional, Shinkai, Hisaaki, additional, Somiya, Kentaro, additional, Sotani, Hajime, additional, Sugiyama, Naoshi, additional, Suwa, Yudai, additional, Suzuki, Rieko, additional, Tagoshi, Hideyuki, additional, Takahashi, Fuminobu, additional, Takahashi, Kakeru, additional, Takahashi, Keitaro, additional, Takahashi, Ryutaro, additional, Takahashi, Ryuichi, additional, Takahashi, Tadayuki, additional, Takahashi, Hirotaka, additional, Akiteru, Takamori, additional, Takano, Tadashi, additional, Taniguchi, Keisuke, additional, Taruya, Atsushi, additional, Tashiro, Hiroyuki, additional, Torii, Yasuo, additional, Toyoshima, Morio, additional, Tsujikawa, Shinji, additional, Tsunesada, Yoshiki, additional, Ueda, Akitoshi, additional, Ueda, Ken-ichi, additional, Utashima, Masayoshi, additional, Wakabayashi, Yaka, additional, Yamakawa, Hiroshi, additional, Yamamoto, Kazuhiro, additional, Yamazaki, Toshitaka, additional, Yokoyama, Jun'ichi, additional, Yoo, Chul-Moon, additional, Yoshida, Shijun, additional, and Yoshino, Taizoh, additional

Published
2009
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215. Constancy of the Constants of Nature

Author

Chiba, Takeshi and Chiba, Takeshi

Abstract

The current observational and experimental bounds on time variation of the constants of Nature are briefly reviewed., Comment: 11 pages, based on a talk presented at "Frontier of Cosmology and Gravitation" (YITP, Kyoto, April 25-27, 2001)

Published
2001

216. Extended Quintessence and its Late-time Domination

Author

Chiba, Takeshi and Chiba, Takeshi

Abstract

Various astronomical observations point towards the evidence for dark energy. One of the most mysterious problem is the coincidence problem: why dark energy becomes dominant only recently. We present a scenario based on extended quintessence models to explain the late-time domination of dark energy without severe fine-tuning of initial conditions and model parameters., Comment: 8 pages

Published
2001
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217. Quintessence Cosmology and Varying $\alpha$

Author

Chiba, Takeshi, Kohri, Kazunori, Chiba, Takeshi, and Kohri, Kazunori

Abstract

If the reported measurements of the time variation of the fine structure constant from observations of distant QSOs are correct, combined with the Oklo limit they would strongly constrain the class of the quintessence potential. If these results prove valid, future satellite experiment (STEP) should measure the induced violation of the weak equivalence principle. Future cosmological observations of nearby $(z \siml 0.5)$ absorption systems would make it clear whether the variation is significant or not., Comment: 7 pages

Published
2001
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218. Lens Model Degeneracy and Cosmological Tests by Strong Gravitational Lensing

Author

Chiba, Takeshi, Takahashi, Ryuichi, Chiba, Takeshi, and Takahashi, Ryuichi

Abstract

We estimate the sensitivity of lensing observables to the parameters in the lens model (isothermal sphere/Navarro-Frenk-White profile) parameters and to cosmological parameters. We find that the observables are primarily dependent on the lens model parameters, while the dependence on cosmological parameters is minor (especially so for the dark energy parameters). We demonstrate the lens model degeneracy by deriving both the projected mass density profile and the circular velocity profile. We also identify a possible source of the problem of fitting the averaged mass profile of CL 0024+1654 with the Navarro-Frenk-White profile., Comment: 7 pages

Published
2001
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219. Gravitational Lens Statistics and The Density Profile of Dark Halos

Author

Takahashi, Ryuichi, Chiba, Takeshi, Takahashi, Ryuichi, and Chiba, Takeshi

Abstract

We investigate the influence of the inner profile of lens objects on gravitational lens statistics taking into account of the effect of magnification bias and both the evolution and the scatter of halo profiles. We take the dark halos as the lens objects and consider the following three models for the density profile of dark halos; SIS (singular isothermal sphere), the NFW (Navarro Frenk White) profile, and the generalized NFW profile which has a different slope at smaller radii. The mass function of dark halos is assumed to be given by the Press-Schechter function. We find that magnification bias for the NFW profile is order of magnitude larger than that for SIS. We estimate the sensitivity of the lensing probability of distant sources to the inner profile of lenses and to the cosmological parameters. It turns out that the lensing probability is strongly dependent on the inner density profile as well as on the cosmological constant. We compare the predictions with the largest observational sample, the Cosmic Lens All-Sky Survey. The absence or presence of large splitting events in larger surveys currently underway such as the 2dF and SDSS could set constraints on the inner density profile of dark halos., Comment: 22 pages, minor changes and references added, accepted for publication in ApJ

Published
2001
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220. BI-1-7 Space gravitational wave detector : DECIGO & DPF

Author

Musha, Mitsuru, Kawamura, Seiji, Ando, Masaki, Seto, Naoki, Sato, Shuichi, Nakamura, Takashi, Tsubono, Kimio, Takashima, Takeshi, Funaki, Ikko, Numata, Kenji, Kanda, Nobuyuki, Tanaka, Takahiro, Ioka, Kunihito, Aoyagi, Kosuke, Wagatsuma, Kazuhiro, Asada, Hideki, Aso, Yoichi, Arai, Koji, Araya, Akito, Ikegami, Takeshi, Ishikawa, Takehiko, Ishizaki, Hideharu, Ishidoshiro, Koji, Ishihara, Hideki, Izumi, Kiwamu, Ichiki, Kiyotomo, Ito, Hiroyuki, Ito, Yosuke, Inoue, Kaiki, Ueda, Akitoshi, Ueda, Kenichi, Utashima, Masayoshi, Ejiri, Yumiko, Enoki, Motohiro, Ebisuzaki, Toshikazu, Eriguchi, Yoshiharu, Oishi, Naoko, Okawa, Masashi, Ohashi, Masatake, Ohara, Kenichi, Obuchi, Yoshiyuki, Okada, Kenshi, Kawashima, Nobuki, Kawazoe, Fumiko, Kono, Isao, Kiuchi, Kenta, Kishimoto, Naoko, Kuninaka, Hitoshi, Kunimori, Hiro, Kuroda, Kazuaki, Koizumi, Hiroyuki, [checking], Kori, Kazunori, Kokuyama, Wataru, Kokeyama, Keiko, Kozai, Yoshihide, Kojima, Yasufumi, Kotake, Kei, Kobayashi, Shiho, Saijo, Motoyuki, Saito, Ryo, Sakai, Shinichiro, Sakagami, Masaaki, Sakata, Shihori, Sago, Norichika, Sasaki, Takashi, Sato, Takashi, Shibata, Masaru, Shinkai, Hisaaki, Sugiyama, Naoshi, Suzuki, Rieko, Suwa, Yudai, Somiya, Kentaro, Sotani, Hajime, Takano, Tadashi, Takahashi, Kakeru, Takahashi, Keitaro, Takahashi, Tadayuki, Takahashi, Hirotaka, Takahashi, Fuminobu, Takahashi, Ryuichi, Takahashi, Ryutaro, Takamori, Akiteru, Tagoshi, Hideyuki, Tashiro, Hiroyuki, Taniguchi, Keisuke, Taruya, Atsushi, Chiba, Takeshi, Tsujikawa, Shinji, Tsunesada, Yoshiki, Toyoshima, Morio, Torii, Yasuo, Naito, Isao, Nakao, Kenichi, Nakazawa, Kazuhiro, Nakasuka, Shinichi, Nakano, Hiroyuki, Nagano, Shigeo, Nakamura, Koji, Nakamura, Masaharu, Nakayama, Yoshinori, Nishizawa, Atsushi, Nishida, Erina, Nishiyama, Kazutaka, Niwa, Yoshito, Nomi, Taiga, Hashimoto, Tatsuaki, Hayama, Kazuhiro, Harada, Tomohiro, Hikita, Wataru, Himemoto, Yoshiaki, Hirabayashi, Hisashi, Hiramatsu, Naoshi, Fukushima, Mitsuhiro, Fujita, Ryuichi, Fujimoto, Masakatsu, Futamase, Toshifumi, Hosokawa, Mizuhiko, Horisawa, Hideyuki, Maeda, Keiichi, Matsuhara, Hideo, Mino, Yasushi, Miyagawa, Osamu, Miyamoto, Umpei, Miyoki, Shinji, Mukoyama, Shinji, Morisawa, Yoshiyuki, Morimoto, Mutsuko, Moriwaki, Shigenori, Yagi, Kento, Yamakawa, Hiroshi, Yamazaki, Toshitaka, Yamamoto, Kazuhiro, Yokoyama, Junichi, Yoshida, Shijun, Yoshino, Taizo, Wakabayashi, Yaka, and Sun, Ke-Xun

Abstract

本文データは学協会の許諾に基づきCiNiiから複製したものである

Published
2010

223. Search for a Stochastic Background of 100-MHz Gravitational Waves with Laser Interferometers

Author

Akutsu, Tomotada, primary, Kawamura, Seiji, additional, Nishizawa, Atsushi, additional, Arai, Koji, additional, Yamamoto, Kazuhiro, additional, Tatsumi, Daisuke, additional, Nagano, Shigeo, additional, Nishida, Erina, additional, Chiba, Takeshi, additional, Takahashi, Ryuichi, additional, Sugiyama, Naoshi, additional, Fukushima, Mitsuhiro, additional, Yamazaki, Toshitaka, additional, and Fujimoto, Masa-Katsu, additional

Published
2008
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224. DECIGO: THE JAPANESE SPACE GRAVITATIONAL WAVE ANTENNA

Author

ANDO, MASAKI, primary, KAWAMURA, SEIJI, additional, NAKAMURA, TAKASHI, additional, SETO, NAOKI, additional, TSUBONO, KIMIO, additional, NUMATA, KENJI, additional, TAKAHASHI, RYUICHI, additional, MUSHA, MITSURU, additional, UEDA, KEN-ICHI, additional, FUNAKI, IKKOH, additional, MORIWAKI, SHIGENORI, additional, TAKASHIMA, TAKESHI, additional, SAKAI, SHIN-ICHIRO, additional, SATO, TAKASHI, additional, KANDA, NOBUYUKI, additional, NAGANO, SHIGEO, additional, HOSOKAWA, MIZUHIKO, additional, ISHIKAWA, TAKEHIKO, additional, SATO, SHUICHI, additional, ASO, YOICHI, additional, MORIMOTO, MUTSUKO Y., additional, AGATSUMA, KAZUHIRO, additional, AKUTSU, TOMOMI, additional, AKUTSU, TOMOTADA, additional, AOYANAGI, KOH-SUKE, additional, ARAI, KOJI, additional, ARASE, YUTA, additional, ARAYA, AKITO, additional, ASADA, HIDEKI, additional, CHIBA, TAKESHI, additional, EBISUZAKI, TOSHIKAZU, additional, ENOKI, MOTOHIRO, additional, ERIGUCHI, YOSHIHARU, additional, HONG, FENG-LEI, additional, FUJIMOTO, MASA-KATSU, additional, FUKUSHIMA, MITSUHIRO, additional, FUTAMASE, TOSHIFUMI, additional, GANZU, KATSUHIKO, additional, HARADA, TOMOHIRO, additional, HASHIMOTO, TATSUAKI, additional, HAYAMA, KAZUHIRO, additional, HIKIDA, WATARU, additional, HIMEMOTO, YOSHIAKI, additional, HIRABAYASHI, HISASHI, additional, HIRAMATSU, TAKASHI, additional, HORISAWA, HIDEYUKI, additional, ICHIKI, KIYOTOMO, additional, IKEGAMI, TAKESHI, additional, INOUE, KAIKI T., additional, IOKA, KUNIHITO, additional, ISHIDOSHIRO, KOJI, additional, ITO, HIROYUKI, additional, ITOH, YOUSUKE, additional, KAMAGASAKO, SHOGO, additional, KAWASHIMA, NOBUKI, additional, KAWAZOE, FUMIKO, additional, KIRIHARA, HIROYUKI, additional, KISHIMOTO, NAOKO, additional, KIUCHI, KENTA, additional, KLAUS, WERNER, additional, KOBAYASHI, SHIHO, additional, KOHRI, KAZUNORI, additional, KOIZUMI, HIROYUKI, additional, KOJIMA, YASUFUMI, additional, KOKEYAMA, KEIKO, additional, KOKUYAMA, WATARU, additional, KOTAKE, KEI, additional, KOZAI, YOSHIHIDE, additional, KUDOH, HIDEAKI, additional, KUNIMORI, HIROO, additional, KUNINAKA, HITOSHI, additional, KURODA, KAZUAKI, additional, MAEDA, KEI-ICHI, additional, MATSUHARA, HIDEO, additional, MINO, YASUSHI, additional, MIURA, JUN-ICHI, additional, MIYAKAWA, OSAMU, additional, MIYOKI, SHINJI, additional, MORIOKA, TOMOKO, additional, MORISAWA, TOSHIYUKI, additional, MUKOHYAMA, SHINJI, additional, NAITO, ISAO, additional, NAKAGAWA, NORIYASU, additional, NAKAMURA, KOUJI, additional, NAKANO, HIROYUKI, additional, NAKAO, KENICHI, additional, NAKASUKA, SHINICHI, additional, NAKAYAMA, YOSHINORI, additional, NISHIDA, ERINA, additional, NISHIYAMA, KAZUTAKA, additional, NISHIZAWA, ATSUSHI, additional, NIWA, YOSHITO, additional, OHASHI, MASATAKE, additional, OHISHI, NAOKO, additional, OHKAWA, MASASHI, additional, OKUTOMI, AKIRA, additional, ONOZATO, KOUJI, additional, OOHARA, KENICHI, additional, SAGO, NORICHIKA, additional, SAIJO, MOTOYUKI, additional, SAKAGAMI, MASAAKI, additional, SAKATA, SHIHORI, additional, SASAKI, MISAO, additional, SHIBATA, MASARU, additional, SHINKAI, HISAAKI, additional, SOMIYA, KENTARO, additional, SOTANI, HAJIME, additional, SUGIYAMA, NAOSHI, additional, TAGOSHI, HIDEYUKI, additional, TAKAHASHI, TADAYUKI, additional, TAKAHASHI, RYUTARO, additional, TAKAHASHI, KAKERU, additional, TAKAHASHI, HIROTAKA, additional, AKITERU, TAKAMORI, additional, TAKANO, TADASHI, additional, TANAKA, TAKAHIRO, additional, TANIGUCHI, KEISUKE, additional, TARUYA, ATSUSHI, additional, TASHIRO, HIROYUKI, additional, TOKUDA, MITSURU, additional, TOKUNARI, MASAO, additional, TOYOSHIMA, MORIO, additional, TSUJIKAWA, SHINJI, additional, TSUNESADA, YOSHIKI, additional, UTASHIMA, MASAYOSHI, additional, YAMAKAWA, HIROSHI, additional, YAMAMOTO, KAZUHIRO, additional, YAMAZAKI, TOSHITAKA, additional, YOKOYAMA, JUN'ICHI, additional, YOO, CHUL-MOON, additional, YOSHIDA, SHIJUN, additional, and YOSHINO, TAIZOH, additional

Published
2008
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229. Determining the Equation of State of the Expanding Universe Using a New Independent Variable

Author

Nakamura, Takashi, Chiba, Takeshi, Nakamura, Takashi, and Chiba, Takeshi

Abstract

To determine the equation of state of the universe, we propose to use a new independent variable $R\equiv (H_0/c)(d_L(z)/(1+z))$, where $H_0$ and $d_L(z)$ are the present Hubble parameter and the luminosity distance, respectively. For the flat universe suggested from the observation of the anisotropy of cosmic microwave background, the density and the pressure are expressed as $\rho/\rho_0=4(df/dR)^2/f^6$ and $p/\rho_0=-4/3(d^2f/dR^2)/f^5$ where $\rho_0$ is the present density and $f(R)=1/\sqrt{1+z(R)}$. In $(R, f)$ plane the sign as well as the strength of the pressure is in proportion to the curvature of the curve $f(R)$. We propose to adopt a Pade-like expression of $f(R)=1/\sqrt{u}$ with $u\equiv 1+\sum\limits_{n=1}^{N}u_nR^n$. For flat $\Lambda$ model the expansion up to N=7 has at most an error $< 0.2%$ for $z < 1.7$ and any value of $\Lambda$. We also propose a general method to determine the equation of state of the universe which has $N-1$ free parameters. If the number of parameters are smaller than $N-1$, there is a consistency check of the equation of state so that we may confirm or refute each model., Comment: 12 pages, to be published in the Astrophysical Journal

Published
2000
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230. Feasibility of Reconstructing the Quintessential Potential Using SNIa Data

Author

Chiba, Takeshi, Nakamura, Takashi, Chiba, Takeshi, and Nakamura, Takashi

Abstract

We investigate the feasibility of the method for reconstructing the equation of state and the effective potential of the quintessence field from SNIa data. We introduce a useful functional form to fit the luminosity distance with good accuracy (the relative error is less than 0.1%). We assess the ambiguity in reconstructing the equation of state and the effective potential which originates from the uncertainty in $\Omega_M$. We find that the equation of state is sensitive to the assumed $\Omega_M$, while the shape of the effective potential is not. We also demonstrate the actual reconstruction procedure using the data created by Monte-Carlo simulation. Future high precision measurements of distances to thousands of SNIa could reveal the shape of the quintessential potential., Comment: 12 pages. Updates to match accepted version

Published
2000
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237. Search for a Stochastic Background of 100-MHz GravitationalWaves with Laser Interferometers

Author

Akutsu, Tomotada, Kawamura, Seiji, Nishizawa, Atsushi, Arai, Koji, Yamamoto, Kazuhiro, Tatsumi, Daisuke, Nagano, Shigeo, Nishida, Erina, Chiba, Takeshi, Takahashi, Ryuichi, Sugiyama, Naoshi, Fukushima, Mitsuhiro, Yamazaki, Toshitaka, and Fujimoto, Masa-Katsu

Abstract

This Letter reports the results of a search for a stochastic background of gravitational waves (GW) at 100 MHz by laser interferometry. We have developed a GW detector, which is a pair of 75-cm baseline synchronous recycling (resonant recycling) interferometers. Each interferometer has a strain sensitivity of ～10^{-16} Hz^{-1/2} at 100 MHz. By cross-correlating the outputs of the two interferometers within 1000 seconds, we found h^2 100Ω_gw < 6 ×10^25 to be an upper limit on the energy density spectrum of the GW background in a 2-kHz bandwidth around 100 MHz, where a flat spectrum is assumed.

Published
2008

238. The Japanese space gravitational wave antenna—DECIGO

Author

Kawamura, Seiji, primary, Nakamura, Takashi, additional, Ando, Masaki, additional, Seto, Naoki, additional, Tsubono, Kimio, additional, Numata, Kenji, additional, Takahashi, Ryuichi, additional, Nagano, Shigeo, additional, Ishikawa, Takehiko, additional, Musha, Mitsuru, additional, Ueda, Ken-ichi, additional, Sato, Takashi, additional, Hosokawa, Mizuhiko, additional, Agatsuma, Kazuhiro, additional, Akutsu, Tomotada, additional, Aoyanagi, Koh-suke, additional, Arai, Koji, additional, Araya, Akito, additional, Asada, Hideki, additional, Aso, Yoichi, additional, Chiba, Takeshi, additional, Ebisuzaki, Toshikazu, additional, Eriguchi, Yoshiharu, additional, Fujimoto, Masa-Katsu, additional, Fukushima, Mitsuhiro, additional, Futamase, Toshifumi, additional, Ganzu, Katsuhiko, additional, Harada, Tomohiro, additional, Hashimoto, Tatsuaki, additional, Hayama, Kazuhiro, additional, Hikida, Wataru, additional, Himemoto, Yoshiaki, additional, Hirabayashi, Hisashi, additional, Hiramatsu, Takashi, additional, Ichiki, Kiyotomo, additional, Ikegami, Takeshi, additional, Inoue, Kaiki T, additional, Ioka, Kunihito, additional, Ishidoshiro, Koji, additional, Itoh, Yousuke, additional, Kamagasako, Shogo, additional, Kanda, Nobuyuki, additional, Kawashima, Nobuki, additional, Kirihara, Hiroyuki, additional, Kiuchi, Kenta, additional, Kobayashi, Shiho, additional, Kohri, Kazunori, additional, Kojima, Yasufumi, additional, Kokeyama, Keiko, additional, Kozai, Yoshihide, additional, Kudoh, Hideaki, additional, Kunimori, Hiroo, additional, Kuroda, Kazuaki, additional, Maeda, Kei-ichi, additional, Matsuhara, Hideo, additional, Mino, Yasushi, additional, Miyakawa, Osamu, additional, Miyoki, Shinji, additional, Mizusawa, Hiromi, additional, Morisawa, Toshiyuki, additional, Mukohyama, Shinji, additional, Naito, Isao, additional, Nakagawa, Noriyasu, additional, Nakamura, Kouji, additional, Nakano, Hiroyuki, additional, Nakao, Kenichi, additional, Nishizawa, Atsushi, additional, Niwa, Yoshito, additional, Nozawa, Choetsu, additional, Ohashi, Masatake, additional, Ohishi, Naoko, additional, Ohkawa, Masashi, additional, Okutomi, Akira, additional, Oohara, Kenichi, additional, Sago, Norichika, additional, Saijo, Motoyuki, additional, Sakagami, Masaaki, additional, Sakata, Shihori, additional, Sasaki, Misao, additional, Sato, Shuichi, additional, Shibata, Masaru, additional, Shinkai, Hisaaki, additional, Somiya, Kentaro, additional, Sotani, Hajime, additional, Sugiyama, Naoshi, additional, Tagoshi, Hideyuki, additional, Takahashi, Tadayuki, additional, Takahashi, Hirotaka, additional, Takahashi, Ryutaro, additional, Takano, Tadashi, additional, Tanaka, Takahiro, additional, Taniguchi, Keisuke, additional, Taruya, Atsushi, additional, Tashiro, Hiroyuki, additional, Tokunari, Masao, additional, Tsujikawa, Shinji, additional, Tsunesada, Yoshiki, additional, Yamamoto, Kazuhiro, additional, Yamazaki, Toshitaka, additional, Yokoyama, Jun'ichi, additional, Yoo, Chul-Moon, additional, Yoshida, Shijun, additional, and Yoshino, Taizoh, additional

Published
2006
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