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arXiv · 2006.13545

Current status of space gravitational wave antenna DECIGO and B-DECIGO

Abstract

Deci-hertz Interferometer Gravitational Wave Observatory (DECIGO) is the future Japanese space mission with a frequency band of 0.1 Hz to 10 Hz. DECIGO aims at the detection of primordial gravitational waves, which could be produced during the inflationary period right after the birth of the universe. There are many other scientific objectives of DECIGO, including the direct measurement of the acceleration of the expansion of the universe, and reliable and accurate predictions of the timing and locations of neutron star/black hole binary coalescences. DECIGO consists of four clusters of observatories placed in the heliocentric orbit. Each cluster consists of three spacecraft, which form three Fabry-Perot Michelson interferometers with an arm length of 1,000 km. Three clusters of DECIGO will be placed far from each other, and the fourth cluster will be placed in the same position as one of the three clusters to obtain the correlation signals for the detection of the primordial gravitational waves. We plan to launch B-DECIGO, which is a scientific pathfinder of DECIGO, before DECIGO in the 2030s to demonstrate the technologies required for DECIGO, as well as to obtain fruitful scientific results to further expand the multi-messenger astronomy.

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Seiji Kawamura, Masaki Ando, Naoki Seto, Shuichi Sato, Mitsuru Musha, Isao Kawano, Jun'ichi Yokoyama, Takahiro Tanaka, Kunihito Ioka, Tomotada Akutsu, Takeshi Takashima, Kazuhiro Agatsuma, Akito Araya, Naoki Aritomi, Hideki Asada, Takeshi Chiba, Satoshi Eguchi, Motohiro Enoki, Masa-Katsu Fujimoto, Ryuichi Fujita, Toshifumi Futamase, Tomohiro Harada, Kazuhiro Hayama, Yoshiaki Himemoto, Takashi Hiramatsu, Feng-Lei Hong, Mizuhiko Hosokawa, Kiyotomo Ichiki, Satoshi Ikari, Hideki Ishihara, Tomohiro Ishikawa, Yousuke Itoh, Takahiro Ito, Shoki Iwaguchi, Kiwamu Izumi, Nobuyuki Kanda, Shinya Kanemura, Fumiko Kawazoe, Shiho Kobayashi, Kazunori Kohri, Yasufumi Kojima, Keiko Kokeyama, Kei Kotake, Sachiko Kuroyanagi, Kei-ichi Maeda, Shuhei Matsushita, Yuta Michimura, Taigen Morimoto, Shinji Mukohyama, Koji Nagano, Shigeo Nagano, Takeo Naito, Kouji Nakamura, Takashi Nakamura, Hiroyuki Nakano, Kenichi Nakao, Shinichi Nakasuka, Yoshinori Nakayama, Kazuhiro Nakazawa, Atsushi Nishizawa, Masashi Ohkawa, Kenichi Oohara, Norichika Sago, Motoyuki Saijo, Masaaki Sakagami, Shin-ichiro Sakai, Takashi Sato, Masaru Shibata, Hisaaki Shinkai, Ayaka Shoda, Kentaro Somiya, Hajime Sotani, Ryutaro Takahashi, Hirotaka Takahashi, Takamori Akiteru, Keisuke Taniguchi, Atsushi Taruya, Kimio Tsubono, Shinji Tsujikawa, Akitoshi Ueda, Ken-ichi Ueda, Izumi Watanabe, Kent Yagi, Rika Yamada, Shuichiro Yokoyama, Chul-Moon Yoo, Zong-Hong Zhu. 2020-06-24. Current status of space gravitational wave antenna DECIGO and B-DECIGO. https://arxiv.org/abs/2006.13545

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