Detecting a gravitationalwave background with nextgeneration space interferometers
Abstract
Future missions of gravitationalwave astronomy will be operated by spacebased interferometers, covering a very wide range of frequencies. Search for stochastic gravitationalwave backgrounds (GWBs) is one of the main targets for such missions, and we here discuss the prospects for direct measurement of isotropic and anisotropic components of (primordial) GWBs around the frequency 0.110 Hz. After extending the theoretical basis for correlation analysis, we evaluate the sensitivity and the signaltonoise ratio for the proposed future space interferometer missions, like BigBang Observer (BBO), DeciHertz Interferometer Gravitationalwave Observer (DECIGO), and the recently proposed FabryPerot type DECIGO. The astrophysical foregrounds which are expected at low frequency may be a big obstacle and may significantly reduce the signaltonoise ratio of GWBs. As a result, the minimum detectable amplitude may reach h{sup 2}{omega}{sub gw}=10{sup 15}{approx}10{sup 16}, as long as foreground point sources are properly subtracted. Based on correlation analysis, we also discuss measurement of anisotropies of GWBs. As an example, the sensitivity level required for detecting the dipole moment of GWB induced by the proper motion of our local system is closely examined.
 Authors:
 Department of Physics, University of Tokyo, Tokyo 1130033 (Japan)
 Research Center for the Early Universe (RESCEU), School of Science, University of Tokyo, Tokyo 1130033 (Japan)
 Publication Date:
 OSTI Identifier:
 20782640
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.73.064006; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; AMPLITUDES; ANISOTROPY; CORRELATIONS; COSMOLOGY; DIPOLE MOMENTS; GRAVITATIONAL WAVES; INTERFEROMETERS; POINT SOURCES; PROPER MOTION; SENSITIVITY; SIGNALTONOISE RATIO; SPACE
Citation Formats
Kudoh, Hideaki, Hiramatsu, Takashi, Himemoto, Yoshiaki, and Taruya, Atsushi. Detecting a gravitationalwave background with nextgeneration space interferometers. United States: N. p., 2006.
Web. doi:10.1103/PHYSREVD.73.064006.
Kudoh, Hideaki, Hiramatsu, Takashi, Himemoto, Yoshiaki, & Taruya, Atsushi. Detecting a gravitationalwave background with nextgeneration space interferometers. United States. doi:10.1103/PHYSREVD.73.064006.
Kudoh, Hideaki, Hiramatsu, Takashi, Himemoto, Yoshiaki, and Taruya, Atsushi. Wed .
"Detecting a gravitationalwave background with nextgeneration space interferometers". United States.
doi:10.1103/PHYSREVD.73.064006.
@article{osti_20782640,
title = {Detecting a gravitationalwave background with nextgeneration space interferometers},
author = {Kudoh, Hideaki and Hiramatsu, Takashi and Himemoto, Yoshiaki and Taruya, Atsushi},
abstractNote = {Future missions of gravitationalwave astronomy will be operated by spacebased interferometers, covering a very wide range of frequencies. Search for stochastic gravitationalwave backgrounds (GWBs) is one of the main targets for such missions, and we here discuss the prospects for direct measurement of isotropic and anisotropic components of (primordial) GWBs around the frequency 0.110 Hz. After extending the theoretical basis for correlation analysis, we evaluate the sensitivity and the signaltonoise ratio for the proposed future space interferometer missions, like BigBang Observer (BBO), DeciHertz Interferometer Gravitationalwave Observer (DECIGO), and the recently proposed FabryPerot type DECIGO. The astrophysical foregrounds which are expected at low frequency may be a big obstacle and may significantly reduce the signaltonoise ratio of GWBs. As a result, the minimum detectable amplitude may reach h{sup 2}{omega}{sub gw}=10{sup 15}{approx}10{sup 16}, as long as foreground point sources are properly subtracted. Based on correlation analysis, we also discuss measurement of anisotropies of GWBs. As an example, the sensitivity level required for detecting the dipole moment of GWB induced by the proper motion of our local system is closely examined.},
doi = {10.1103/PHYSREVD.73.064006},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 73,
place = {United States},
year = {Wed Mar 15 00:00:00 EST 2006},
month = {Wed Mar 15 00:00:00 EST 2006}
}

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