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Title: Lepton asymmetry in the primordial gravitational wave spectrum

Abstract

Effects of neutrino free streaming are evaluated on the primordial spectrum of gravitational radiation taking both neutrino chemical potential and masses into account. The former or the lepton asymmetry induces two competitive effects, namely, to increase anisotropic stress, which damps the gravitational wave more, and to delay the matter-radiation equality time, which reduces the damping. The latter effect is more prominent and a large lepton asymmetry would reduce the damping. We may thereby be able to measure the magnitude of lepton asymmetry from the primordial gravitational wave spectrum.

Authors:
 [1];  [2];  [1];  [3]
  1. Research Center for the Early Universe (RESCEU), Graduate School of Science, University of Tokyo, Tokyo 113-0033 (Japan)
  2. Department of Physics and Mathematics, Aoyama Gakuin University, Sagamihara 229-8558 (Japan)
  3. (Italy)
Publication Date:
OSTI Identifier:
21020386
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.75.084017; (c) 2007 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; ANISOTROPY; ASYMMETRY; COSMOLOGY; GRAVITATIONAL RADIATION; GRAVITATIONAL WAVES; NEUTRINOS; POTENTIALS; QUANTUM FIELD THEORY; REST MASS; STRESSES

Citation Formats

Ichiki, Kiyotomo, Yamaguchi, Masahide, Yokoyama, Jun'Ichi, and Galileo Galilei Institute for Theoretical Physics, Arcetri, Florence. Lepton asymmetry in the primordial gravitational wave spectrum. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.084017.
Ichiki, Kiyotomo, Yamaguchi, Masahide, Yokoyama, Jun'Ichi, & Galileo Galilei Institute for Theoretical Physics, Arcetri, Florence. Lepton asymmetry in the primordial gravitational wave spectrum. United States. doi:10.1103/PHYSREVD.75.084017.
Ichiki, Kiyotomo, Yamaguchi, Masahide, Yokoyama, Jun'Ichi, and Galileo Galilei Institute for Theoretical Physics, Arcetri, Florence. Sun . "Lepton asymmetry in the primordial gravitational wave spectrum". United States. doi:10.1103/PHYSREVD.75.084017.
@article{osti_21020386,
title = {Lepton asymmetry in the primordial gravitational wave spectrum},
author = {Ichiki, Kiyotomo and Yamaguchi, Masahide and Yokoyama, Jun'Ichi and Galileo Galilei Institute for Theoretical Physics, Arcetri, Florence},
abstractNote = {Effects of neutrino free streaming are evaluated on the primordial spectrum of gravitational radiation taking both neutrino chemical potential and masses into account. The former or the lepton asymmetry induces two competitive effects, namely, to increase anisotropic stress, which damps the gravitational wave more, and to delay the matter-radiation equality time, which reduces the damping. The latter effect is more prominent and a large lepton asymmetry would reduce the damping. We may thereby be able to measure the magnitude of lepton asymmetry from the primordial gravitational wave spectrum.},
doi = {10.1103/PHYSREVD.75.084017},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 75,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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