Paper: astro-ph/0506422
Date: Fri, 17 Jun 2005 20:00:06 GMT (91kb)

Title: Direct detection of the inflationary gravitational wave background

Authors: Tristan L. Smith (Caltech), Marc Kamionkowski (Caltech) and Asantha
Cooray (Caltech and UC Irvine)
Comments: 14 pages, 4 figures, RevTex, submitted to Phys. Rev. D
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Inflation generically predicts a stochastic background of gravitational waves
over a broad range of frequencies, from those accessible with cosmic microwave
background (CMB) measurements, to those accessible directly with
gravitational-wave detectors, like NASA's Big-Bang Observer (BBO) or Japan's
Deci-Hertz Interferometer Gravitational-wave Observer (DECIGO), both currently
under study. Here we investigate the detectability of the inflationary
gravitational-wave background at BBO/DECIGO frequencies. To do so, we survey a
range of slow-roll inflationary models consistent with constraints from the CMB
and large-scale structure (LSS). We go beyond the usual assumption of power-law
power spectra, which may break down given the 16 orders of magnitude in
frequency between the CMB and direct detection, and solve instead the
inflationary dynamics for four classes of inflaton potentials. Direct detection
is possible in a variety of inflationary models, although probably not in any
in which the gravitational-wave signal does not appear in the CMB polarization.
However, direct detection by BBO/DECIGO can help discriminate between
inflationary models that have the same slow-roll parameters at CMB/LSS scales.

http://arXiv.org/abs/astro-ph/0506422