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Title: Quest for circular polarization of a gravitational wave background and orbits of laser interferometers in space

Abstract

We show that an isotropic component of circular polarization of a stochastic gravitational wave background can be explored by contriving configuration of multiple laser interferometers for correlation analysis. For the proposed BBO mission, the circular polarization degree {pi} can be measured down to {pi}{approx}0.08({omega}{sub GW}/10{sup -15}){sup -1}(SNR/5) with slightly ({approx}10%) sacrificing the detection limit for the total intensity {omega}{sub GW}. This might allow us to detect a signature of parity violation in the very early universe.

Authors:
 [1]
  1. Department of Physics and Astronomy, 4186 Frederick Reines Hall, University of California, Irvine, California 92697 (United States)
Publication Date:
OSTI Identifier:
21020114
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.75.061302; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; CORRELATIONS; COSMOLOGY; GRAVITATIONAL WAVE DETECTORS; GRAVITATIONAL WAVES; INTERFEROMETERS; INTERFEROMETRY; LASER RADIATION; LASERS; ORBITS; P INVARIANCE; POLARIZATION; SENSITIVITY; UNIVERSE

Citation Formats

Seto, Naoki. Quest for circular polarization of a gravitational wave background and orbits of laser interferometers in space. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.061302.
Seto, Naoki. Quest for circular polarization of a gravitational wave background and orbits of laser interferometers in space. United States. doi:10.1103/PHYSREVD.75.061302.
Seto, Naoki. Thu . "Quest for circular polarization of a gravitational wave background and orbits of laser interferometers in space". United States. doi:10.1103/PHYSREVD.75.061302.
@article{osti_21020114,
title = {Quest for circular polarization of a gravitational wave background and orbits of laser interferometers in space},
author = {Seto, Naoki},
abstractNote = {We show that an isotropic component of circular polarization of a stochastic gravitational wave background can be explored by contriving configuration of multiple laser interferometers for correlation analysis. For the proposed BBO mission, the circular polarization degree {pi} can be measured down to {pi}{approx}0.08({omega}{sub GW}/10{sup -15}){sup -1}(SNR/5) with slightly ({approx}10%) sacrificing the detection limit for the total intensity {omega}{sub GW}. This might allow us to detect a signature of parity violation in the very early universe.},
doi = {10.1103/PHYSREVD.75.061302},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
  • The Stokes V parameter characterizes asymmetry of amplitudes between right- and left-handed waves, and the nonvanishing value of the V parameter yields a circularly polarized signal. Cosmologically, the V parameter may be a direct probe for parity violation in the Universe. In this paper, we theoretically investigate a measurement of this parameter, particularly focusing on the gravitational-wave backgrounds observed via ground-based interferometers. In contrast to the traditional analysis that only considers the total amplitude (or equivalently {omega}{sub GW}), the signal analysis including a circular-polarized mode has a rich structure due to the multidimensionality of target parameters. We show that, bymore » using the network of next-generation detectors, separation between polarized and unpolarized modes can be performed with small statistical loss induced by their correlation.« less
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