A5107206492- Pulsars and Gravitational Waves Research
- Geophysics and Sensor Technology
- Advanced Frequency and Time Standards
- Geophysics and Gravity Measurements
- Gamma-ray bursts and supernovae
- Seismic Waves and Analysis
- Advanced Measurement and Metrology Techniques
- High-pressure geophysics and materials
- Astrophysical Phenomena and Observations
- Scientific Measurement and Uncertainty Evaluation
- Cosmology and Gravitation Theories
- Astronomical Observations and Instrumentation
- Cold Atom Physics and Bose-Einstein Condensates
- Astrophysics and Cosmic Phenomena
- Advanced Fiber Laser Technologies
- Atomic and Subatomic Physics Research
- Magnetic confinement fusion research
- Adaptive optics and wavefront sensing
- Advanced Sensor Technologies Research
- Advanced Surface Polishing Techniques
- Particle Accelerators and Free-Electron Lasers
- Radiation Dose and Imaging
- Optical measurement and interference techniques
- Surface Roughness and Optical Measurements
- Laser Design and Applications
National Institute of Advanced Industrial Science and Technology
2012-2023
The University of Tokyo
1997-2020
Japan Advanced Institute of Science and Technology
2019-2020
High Energy Accelerator Research Organization
2013
Tsukuba University of Technology
2004-2006
National Astronomical Observatory of Japan
1999-2003
National Institute for Materials Science
2001
National Institutes of Natural Sciences
1999
The Graduate University for Advanced Studies, SOKENDAI
1997
TAMA300, an interferometric gravitational-wave detector with 300-m baseline length, has been developed and operated sufficient sensitivity to detect events within our galaxy stability for observations; the interferometer was over 10 hours stably continuously. With a strain-equivalent noise level of $h\ensuremath{\sim}5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}21}/\sqrt{\mathrm{Hz}}$, signal-to-noise ratio 30 is expected gravitational waves generated by coalescence...
We present here the Large-scale Cryogenic Gravitational wave Telescope (LCGT) project which is aimed to improve sensitivity of existing gravitational projects by ten times. LCGT constructing km-scale detector in Japan succeeding TAMA project, adopts cryogenic mirrors with a higher power laser. are planing build it an underground site Kamioka mine. If its target attained, we will be able catch few events per month.
We analyzed 6 hours of data from the TAMA300 detector by matched filtering, searching for gravitational waves inspiraling compact binaries. incorporated a two-step hierarchical search strategy in filtering. obtained an upper limit 0.59/hour (C.L.=90%) on event rate inspirals binaries with mass between 0.3M⊙ and 10M⊙ signal-to-noise ratio greater than 7.2. The distance 1.4M⊙(0.5M⊙) which produce 7.2 was estimated to be 6.2 kpc (2.9 kpc) when position source sky inclination angle were...
The thermal fluctuation of mirror surfaces is the fundamental limitation for interferometric gravitational wave (GW) detectors. Here, we experimentally demonstrate first time a reduction in mirror's GW detector with sapphire mirrors from Cryogenic Laser Interferometer Observatory at 17 and 18 K. sensitivity, which was limited by room temperature, improved frequency range 90 to 240 Hz cooling mirrors. sensitivity reached maximum 2.2×10(-19) m/√Hz 165 Hz.
The large-scale cryogenic gravitational wave telescope (LCGT) is the future project of Japanese group. Two sets 3 km arm length laser interferometric detectors will be built in a tunnel Kamioka mine Japan. LCGT detect chirp waves from binary neutron star coalescence at 240 Mpc away with S/N 10. expected number detectable events year two or three. To achieve required sensitivity, several advanced techniques employed such as low-frequency vibration-isolation system, suspension point...
The Large-scale Cryogenic Gravitational wave Telescope (LCGT) is planned as a future Japanese project for gravitational detection. A 3 km interferometer will be built in an underground mine at Kamioka. sapphire mirrors are going to employed the test masses. For demonstration of LCGT technologies, two prototype interferometers, TAMA300 and CLIO, being developed. This paper describes current status interferometers.
CLIO (Cryogenic Laser Interferometer Observatory) is a Japanese gravitational wave detector project. One of the main purposes to demonstrate thermal-noise suppression by cooling mirrors for future project, LCGT (Large-scale Cryogenic Gravitational Telescope). The site in Kamioka mine, as LCGT. progress between 2005 and 2007 (room- cryogenic-temperature experiments) introduced this article. In room-temperature experiment, we made efforts improve sensitivity. current best sensitivity at 300 K...
The CLIO project involves the Cryogenic Laser Interferometer Observatory (CLIO) detector complex for gravitational wave detection and Kamioka Interferometric Strainmeter acquisition of geophysical data. has been constructed to demonstrate feasibility a future project, Large-scale Gravitational Telescope (LCGT). It will utilize low seismic stable environment mine as well sapphire mirrors suspension fibres at temperature reduce thermal noise. We designed have noise level limited by fibres,...
We present data-analysis schemes and results of observations with the TAMA300 gravitational wave detector, targeting burst signals from stellar-core collapse events. In analyses for waves, detection fake-reduction are different well-investigated ones a chirp analysis, because precise waveform templates not available. used an excess -power filter extraction candidates, developed two methods reduction fake events caused by nonstationary noises detector. These analysis were applied to real data...
Current status of TAMA and CLIO detectors in Japan is reported this article.These two interferometric gravitational-wave are being developed for the large cryogenic gravitational wave telescope (LCGT) which a future plan detecting signals at least once per year.TAMA300 upgraded to improve sensitivity low frequency region after last observation experiment 2004.To reduce seismic noises, we installing new isolation system, called Seismic Attenuation System, four test masses.We confirmed stable...
Construction of CLIO (cryogenic laser interferometer observatory) with 100 m baseline length has begun in the Kamioka mine. The tunnel for been dug and infrastructure work is now progress. final step to LCGT (large scale cryogenic gravitational wave telescope) first practical construction a world. objective demonstrate two three features LCGT, which are utilize quietness stable environment underground site adopt sapphire mirrors thermal noise reduction. Also, it joint project by geophysics...
The CLIO project including a 100 m baseline cryogenic gravitational wave laser interferometer and geophysical strain meter was conducted in the Kamioka mine Japan to investigate technical feasibility of large-scale telescope (LCGT), which is planned be constructed same with 30 times longer than CLIO, demonstrate collaborative operation between these instruments about long-term continuous signal veto analysis. About interferometer, whole vacuum system four cryostats, house cool sapphire...
We report on the development of a new type mode cleaner that reduces any geometric noise laser beam in an interferometric gravitational-wave detector. The is Fabry–Perot cavity comprises independently suspended mirrors and works as frequency-stabilization reference well selector; length 1 m. Stand-alone tests have shown at least 30-dB reduction fluctuation 60-dB frequency laser. also succeeded operating 20-m prototype detector (at National Astronomical Observatory, Tokyo, Japan) by using...
The objective of the TAMA 300 interferometer was to develop advanced technologies for kilometre scale interferometers and observe gravitational wave events in nearby galaxies. It designed as a power-recycled Fabry–Perot–Michelson intended step towards final Japan.
In order to detect the rare astrophysical events that generate gravitational wave (GW) radiation, a sufficient stability is required for GW antennas allow long-term observation. practice, seismic excitation one of most common disturbances effecting stable operation suspended-mirror laser interferometers. A straightforward means more therefore locate antenna, ``observatory,'' at ``quiet'' site. interferometer antenna with baseline length 20 m (LISM) was developed site 1000 underground, near...
A laser-based alignment system with a He-Ne laser has been newly developed in order to precisely align accelerator units at the KEKB injector linac. The beam was first implemented as 500-m-long fiducial straight line for measurements. We experimentally investigated propagation and stability characteristics of passing through pipes vacuum. pointing last point successfully obtained transverse displacements ±40 μm level one standard deviation by applying feedback control. This corresponds an...
A new method has been demonstrated for absolute-length measurements of a long-baseline Fabry–Perot cavity by use phase-modulated light. This is based on determination free spectral range (FSR) the from frequency difference between carrier and phase-modulation sidebands, both which resonate in cavity. Sensitive response near resonant frequencies ensures accurate FSR thus absolute length was applied to 300-m TAMA gravitational wave detector that being developed at National Astronomical...
Laser frequency stabilization is essential for interferometric gravitational-wave detectors to attain their target sensitivity. We have designed a multistage laser system which has been applied in the development of TAMA 300 detector Japan. The control topology consisting two cascaded loops were employed secure high feedback gain and reliable operation thus allow best stability uninterrupted long-term observation. achieved simultaneously 5×10−5 Hz/Hz, common-mode rejection ratio (which...
The large-scale cryogenic gravitational wave telescope (LCGT) project is the proposed advancement of TAMA, which will be able to detect coalescences binary neutron stars occurring in our galaxy. LCGT intends coalescence events within about 240 Mpc, rate expected from 0.1 several a year. has Fabry–Perot cavities 3 km baseline and mirrors are cooled down temperature 20 K. It planned built underground Kamioka mine. This paper overviews revision design current status R&D.
We report on the current status of CLIO (Cryogenic Laser Interferometer Observatory), which is a prototype interferometer for LCGT (large scale cryogenic gravitational-wave telescope). Japanese next-generation interferometric detector featuring use mirrors and quiet underground site. The main purpose to demonstrate reduction mirror thermal noise by cooling sapphire mirrors. located in an site Kamioka mine, 1000 m deep from mountain top, verify its advantages. After few years commissioning...
Japanese laser interferometric gravitational wave detectors, TAMA300 and LISM, performed a coincident observation during 2001. We perform coincidence analysis to search for inspiraling compact binaries. The length of data used the is 275 hours when both LISM detectors are operated simultaneously. analyzed by matched filtering, candidates events obtained. If there true signal, it should appear in with consistent waveforms characterized masses stars, amplitude coalescence time so on. introduce...
A remarkable design of LCGT was established by experimental efforts to detect gravitational waves in Japan including optional alternatives detail. The adopts an advanced technique regarded be used the third generation. We can reliably and still have a chance firstly it.