Transcript Laser and optical technologies for gravitational wave

Sora
ICSOS @Tokyo, Japan
Feb. 5, 2009
Seiji Kawamura, Masaki Ando, Takashi Nakamura, Kimio Tsubono, Naoki Seto, Shuichi Sato, Kenji Numata, Nobuyuki Kanda, Ikkoh F unaki, Takeshi Takashima, Takahiro
Tanaka, Kunihito Ioka, Kazuhiro Agatsuma, Koh-suke Aoyanagi, Koji Arai, Akito Araya, Hideki Asada, Yoichi Aso, Takeshi Chiba, Toshikazu Ebisuzaki, Yumiko Ejiri,
Motohiro Enoki, Yoshiharu Eriguchi, 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, Feng-Lei Hong, Hideyuki Horisawa, Mizuhiko Hosokawa,
Kiyotomo Ichiki, Takeshi Ikegami, Kaiki T. Inoue, Koji Ishidoshiro, Hideki Ishihara, Takehiko Ishikawa, Hideharu Ishizaki, Hi royuki Ito, Yousuke Itoh, Nobuki Kawashima,
Fumiko Kawazoe, Naoko Kishimoto, Kenta Kiuchi, Shiho Kobayashi, Kazunori Kohri, Hiroyuki Koizumi, Yasufumi Kojima, Keiko Koke yama, Wataru Kokuyama, Kei Kotake,
Yoshihide Kozai, Hideaki Kudoh, Hiroo Kunimori, Hitoshi Kuninaka, Kazuaki Kuroda, Kei-ichi Maeda, Hideo Matsuhara, Yasushi Mino, Osamu Miyakawa, Shinji Miyoki,
Mutsuko Y. Morimoto, Tomoko Morioka, Toshiyuki Morisawa, Shigenori Moriwaki, Shinji Mukohyama, Mitsuru Musha, Shigeo Nagano, Isao Naito, Kouji Nakamura, Hiroyuki
Nakano, Kenichi Nakao, Shinichi Nakasuka, Yoshinori Nakayama, Kazuhiro Nakazawa, Erina Nishida, Kazutaka Nishiyama, Atsushi N ishizawa, Yoshito Niwa, Yoshiyuki
Obuchi, Masatake Ohashi, Naoko Ohishi, Masashi Ohkawa, Norio Okada, 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 Sug iyama, Yudai Suwa, Rieko Suzuki,
Hideyuki Tagoshi, Fuminobu Takahashi, Kakeru Takahashi, Keitaro Takahashi, Ryutaro Takahashi, Ryuichi Takahashi, Tadayuki Tak ahashi, Hirotaka Takahashi, Takamori
Akiteru, Tadashi Takano, Keisuke Taniguchi, Atsushi Taruya, Hiroyuki Tashiro, Mitsuru Tokuda, Yasuo Torii, Morio Toyoshima, S hinji Tsujikawa, Yoshiki Tsunesada,
Akitoshi Ueda, Ken-ichi Ueda, Masayoshi Utashima, Yaka Wakabayashi, Hiroshi Yamakawa, Kazuhiro Yamamoto, Toshitaka Yamazaki, Jun'ichi Yokoyama, Chul-Moon Yoo,
Shijun Yoshida, Taizoh Yoshino
Outline
1.
2.
3.
4.
Gravitational wave
DECIGO
DECIGO pathfinder
Summary
Gravitational wave
• Predicted by Einstein
• Emitted from accelerating objects
• Propagates as tidal distortion of space
Distortion of space ~ 10-23
Not yet detected!
GW Sources
• Neutron star / black hole
binaries
• Supernova
• Beginning of the universe
• Etc.
How far (old) can we see?
Beginning of
the universe
GW
10 -43 sec
(Planck
time）
Neutrino
EM
1 sec
(Formation of
380,000 year
Proton, Neutron) (Transparent to13.7 billion year
(Now)
radiation)
Detection of GW
by laser interferometer
Suspended Mirror
Suspended Mirror
Beam splitter
Laser
Detector
Interfering
beam
Mirror
The longer arm length gives
larger signals!
Mirror
Mirror
Laser
Photodetector
Mirror
Laser
Photodetector
Large-scale detectors
LIGO (4 km)
GEO (600 m)
TAMA (300 m)
CLIO (100 m)
LIGO (4 km)
VIRGO (3 km)
Space antenna
Much longer arm length
LISA
•
•
•
•
Arm length: 5,000,000km
Frequency range: 1 mHz - 0.1 Hz
Target Source: White dwarf binary, Giant BH coalescence
Optical configuration: Light transponder
LISA project
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 -> Extremely high sensitivity
Strain [Hz-1/2]
10-18
10-20
Terrestrial
detectors
(e.g. LCGT)
LISA
DECIGO
10-22 Confusion
Noise
10-24
10-4
10-2
100
102
Frequency [Hz]
104
Pre-conceptual design
Differential FP interferometer
Arm length: 1000 km
Mirror diameter: 1 m
Laser wavelength：0.532 m
Finesse: 10
Laser power: 10 W
Mirror mass: 100 kg
S/C: drag free
3 interferometers
Arm cavity
Arm cavity
Laser
Photodetector
Drag-free S/C
Mirror
Drag free and FP cavity:
compatible?
S/C I
S/C II
Mirror
Drag free and FP cavity:
compatible?
Relative position
between mirror
and S/C
S/C II
Local
sensor
S/C I
Mirror
Thruster
Thruster
Drag free and FP cavity:
compatible?
Relative position
between mirror
and S/C
S/C II
Local
sensor
No signal
mixture
S/C I
Mirror
Thruster
Thruster
Actuator
Interferometer
output (GW signal)
Orbit and constellation (preliminary)
Earth
Correlation
for stochastic
background
Record disk
Sun
Increase angular
resolution
Science by DECIGO
10-19
Formation of 10-20
Supermassive BH 10-21
Coalescence
5 years
1 cluster
3 months
10-22
10-23
10-24
10-25
Verification
of inflation 10-26
10-3
Acceleration
of Universe
Shot noise
⇓
Correlation
Dark energy
(3 years)
Inflation
Coalescence
-16
(GW=210 )
10-2
10-1
1
10
Frequency [Hz]
102
103
Acceleration of Expansion of
the Universe
Expansion ＋Acceleration?
DECIGO
GW
NS-NS (z～1)
Output
Strain
Template (No Acceleration)
Real Signal ?
Phase Delay～1sec (10 years)
Time
Seto, Kawamura, Nakamura, PRL 87, 221103 (2001)
Science by DECIGO
10-19
Formation of 10-20
Supermassive BH 10-21
Coalescence
5 years
1 cluster
3 months
10-22
10-23
10-24
10-25
Verification
of inflation 10-26
10-3
Acceleration
of Universe
Shot noise
⇓
Correlation
Dark energy
(3 years)
Inflation
Coalescence
-16
(GW=210 )
10-2
10-1
1
10
Frequency [Hz]
102
103
Roadmap
2007 08
09
10
11
12
13
Mission
R&D
Fabrication
14
15
16
17
18
19
R&D
Fabrication
DICIGO Pathfinder
(DPF)
20
21
22
23
24
25
26
R&D
Fabrication
Pre-DECIGO
DECIGO
Objectives
Test of key technologies
Observation run of GW
Detection of GW w/
minimum spec.
Test FP cavity
between S/C
Full GW astronomy
Scope
1 S/C
1 arm
3 S/C
1 interferometer
3 S/C,
3 interferometer
3 or 4 units
DECIGO Pathfinder (DPF)
DPF
DECIGO
Floating Mirrors
Laser
1,000 km
30 cm
PD
Shrink the arm length
from 1,000 km to 30 cm
Drag-free S/C
Small Science Satellite Series
• ISAS/JAXA plan to launch 3 missions in 5
years starting from 2011
• DPF was selected as one of important
mission candidates; a budget for R&D was
allocated
• DPF aims at being selected as 2nd or 3rd
mission (1st mission already selected)
Summary
• GW is a powerful means to explore the
universe.
• DECIGO can detect GWs from the
beginning of the universe and provide
other important science results.
• DPF was selected as on of the
important mission candidates for small
science satellite series.
Let DPF fly!