GWADW Elba, Italy

1
Sora
DECIGO

• GWADW _at_Elba, Italy
• May 15, 2008
• Seiji KAWAMURA, Masaki ANDO, Takashi NAKAMURA,
  Kimio TSUBONO, Takahiro TANAKA, Ikkoh FUNAKI,
  Naoki SETO, Kenji NUMATA, Shuichi SATO, Kunihito
  IOKA, Nobuyuki KANDA, Takeshi TAKASHIMA, Kazuhiro
  AGATSUMA, Tomomi AKUTSU, Tomotada AKUTSU,
  Koh-suke AOYANAGI, Koji ARAI, Yuta ARASE, Akito
  ARAYA, Hideki ASADA, Yoichi ASO, Takeshi CHIBA,
  Toshikazu EBISUZAKI, Motohiro ENOKI, Yoshiharu
  ERIGUCHI, Feng-Lei HONG, Masa-Katsu FUJIMOTO,
  Ryuichi FUJITA, Mitsuhiro FUKUSHIMA, Toshifumi
  FUTAMASE, Katsuhiko GANZU, Tomohiro HARADA,
  Tatsuaki HASHIMOTO, Kazuhiro HAYAMA, Wataru
  HIKIDA, Yoshiaki HIMEMOTO, Hisashi HIRABAYASHI,
  Takashi HIRAMATSU, Hideyuki HORISAWA, Mizuhiko
  HOSOKAWA, Kiyotomo ICHIKI, Takeshi IKEGAMI, Kaiki
  T. INOUE, Koji ISHIDOSHIRO, Takehiko ISHIKAWA,
  Hideharu ISHIZAKI, Hiroyuki ITO, Yousuke ITOH,
  Shogo KAMAGASAKO, Nobuki KAWASHIMA, Fumiko
  KAWAZOE, Hiroyuki KIRIHARA, Naoko KISHIMOTO,
  Kenta KIUCHI, Werner KLAUS, Shiho KOBAYASHI,
  Kazunori KOHRI, Hiroyuki KOIZUMI, Yasufumi
  KOJIMA, Keiko KOKEYAMA, Wataru KOKUYAMA, Kei
  KOTAKE, Yoshihide KOZAI, Hideaki KUDOH, Hiroo
  KUNIMORI, Hitoshi KUNINAKA, Kazuaki KURODA,
  Kei-ichi MAEDA, Hideo MATSUHARA, Yasushi MINO,
  Jun-ichi MIURA, Osamu MIYAKAWA, Shinji MIYOKI,
  Mutsuko Y. MORIMOTO, Tomoko MORIOKA, Toshiyuki
  MORISAWA, Shigenori MORIWAKI, Shinji MUKOHYAMA,
  Mitsuru MUSHA, Shigeo NAGANO, Isao NAITO,
  Noriyasu NAKAGAWA, Kouji NAKAMURA, Hiroyuki
  NAKANO, Kenichi NAKAO, Shinichi NAKASUKA,
  Yoshinori NAKAYAMA, Erina NISHIDA, Kazutaka
  NISHIYAMA, Atsushi NISHIZAWA, Yoshito NIWA,
  Masatake OHASHI, Naoko OHISHI, Masashi OHKAWA,
  Akira OKUTOMI, Kouji ONOZATO, Kenichi OOHARA,
  Norichika SAGO, Motoyuki SAIJO, Masaaki SAKAGAMI,
  Shin-ichiro SAKAI, Shihori SAKATA, Misao SASAKI,
  Takashi SATO, Masaru SHIBATA, Hisaaki SHINKAI,
  Kentaro SOMIYA, Hajime SOTANI, Naoshi SUGIYAMA,
  Yudai SUWA, Hideyuki TAGOSHI, Tadayuki TAKAHASHI,
  Ryutaro TAKAHASHI, Ryuichi TAKAHASHI, Kakeru
  TAKAHASHI, Hirotaka TAKAHASHI, Akiteru TAKAMORI,
  Tadashi TAKANO, Keisuke TANIGUCHI, Atsushi
  TARUYA, Hiroyuki TASHIRO, Mitsuru TOKUDA, Masao
  TOKUNARI, Morio TOYOSHIMA, Shinji TSUJIKAWA,
  Yoshiki TSUNESADA, Ken-ichi UEDA, Masayoshi
  UTASHIMA, Hiroshi YAMAKAWA, Kazuhiro YAMAMOTO,
  Toshitaka YAMAZAKI, Jun'ichi YOKOYAMA, Chul-Moon
  YOO, Shijun YOSHIDA, Taizoh YOSHINO

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Fortune Cookie
July 2007, Amaldi 7 _at_ Sydney
3
We gained momentum! DPF was selected as one of
five important mission candidates for small
science satellite series run by JAXA/ISAS
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What is DECIGO?

• Deci-hertz Interferometer Gravitational Wave
  Observatory
• (Kawamura, et al., CQG 23 (2006) S125-S131)
• Bridges the gap between LISA and terrestrial
  detectors
• Low confusion noise -gt Extremely high sensitivity

Terrestrial detectors (e.g. LCGT)
LISA
Strain Hz-1/2
DECIGO
Confusion Noise
10-4
102
104
100
10-2
Frequency Hz
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Pre-conceptual design
Differential FP interferometer Arm length 1000
km Mirror diameter 1 m Laser wavelength0.532
?m Finesse 10 Laser power 10 W Mirror mass 100
kg S/C drag free 3 interferometers
Arm cavity
Arm cavity
Laser
Mirror
Photo- detector
Drag-free S/C
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Why FP cavity?
Transponder type (e.g. LISA)
Radiation pressure noise f-2
Shot noise f1
Strain
Shot noise
Transponder type (e.g. LISA)
Frequency
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Drag free and FP cavity compatible?
Mirror
8
FP cavity and drag free compatible?
Relative position between mirror and S/C
Local sensor
Mirror
Thruster
Thruster
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Drag free and FP cavity compatible?
Relative position between mirror and S/C
Local sensor
Mirror
Thruster
Thruster
Actuator
Interferometer output (GW signal)
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Orbit and constellation (preliminary)
Earth
Correlation for stochastic background
Record disk
Sun
Increase angular resolution
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Science by DECIGO
10-19 10-20 10-21 10-22 10-23 10-24 10-25 10-26
Formation of Super-massive BH
Radiation pressure noise
1 unit
Strain Hz-1/2
Acceleration of Universe ? Dark energy
Shot noise
Correlation (3 years)
Verification of inflation
10-3 10-2 10-1 1 10 102
103
Frequency Hz
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Requirements

• Acceleration noise should be suppressed below
  radiation pressure noise
• Force noise DECIGO LISA/50
• (Acceleration noise in terms of h 1, Distance
  1/5000, Mass 100)
• Fluctuation of magnetic field, electric field,
  gravitational field, temperature, pressure, etc.
• Sensor noise should be suppressed below shot
  noise.
• Phase noise DECIGO LCGT10
• (Sensor noise in terms of h 1, storage time
  10)
• Frequency noise, intensity noise, beam jitter,
  etc.
• Thruster system should satisfy range, noise,
  bandwidth, and durability.

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Roadmap
RD Fabrication
RD Fabrication
RD Fabrication
DICIGO Pathfinder (DPF)
Pre-DECIGO
DECIGO
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Pre-conceptual design and objectives of DPF
Rigid Cavity
Floating mirror
Laser
Thruster
Local Sensor
Actuator
Observation of GW at 0.1 1 Hz
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Goal sensitivity of DPF
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Expected sources
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Schematic view of DPF
Stabilized laser
Thruster control
Central operator
Thruster head
Housing control
Interferometer
Solar puddle
Interferometer control
Bus
Bus thruster
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Orbit of DPF
500km
Solar Synchronous polar orbid Altitude 500km,
Period 100 min
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Interim organization
PI Kawamura (NAOJ) Deputy Ando (Tokyo)
Executive Committee Kawamura (NAOJ), Ando
(Tokyo), Seto (NAOJ), Nakamura (Kyoto), Tsubono
(Tokyo), Tanaka (Kyoto), Funaki (ISAS), Numata
(Maryland), Sato (Hosei), Kanda (Osaka city),
Takashima (ISAS), Ioka (Kyoto)
Pre-DECIGO Sato (Hosei)
Satellite Funaki (ISAS)
Science, Data Tanaka (Kyoto) Seto (NAOJ) Kanda
(Osaka city)
Detector Numata (Maryland) Ando (Tokyo)
Design phase
DECIGO pathfinder Leader Ando (Tokyo) Deputy
Takashima (ISAS)
Mission phase
Detector Ando (Tokyo)
Housing Sato (Hosei)
Laser Ueda (ILS) Musya (ILS)
Drag free Moriwaki (Tokyo) Sakai (ISAS)
Thruster Funaki (ISAS)
Bus Takashima (ISAS)
Data Kanda (Osaka city)
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Current status

• There are now 140 members from 50 institutes in
  DECIGO working group
• DPF was selected as one of five important mission
  candidates for small science satellite series run
  by JAXA/ISAS a budget for RD was allocated
• At the end of 2008, the 2nd and 3rd missions will
  be selected. (1st mission already selected)

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Let DPF fly!