Tuning the stochastic background of gravitational waves using the WMAP data

TL;DR

This paper uses WMAP data to refine bounds on the stochastic gravitational wave background, showing they are higher than COBE bounds but still below ground-based detector frequencies, and discusses implications for future detection efforts.

Contribution

It provides updated cosmological bounds on gravitational wave backgrounds using WMAP data, improving upon previous COBE-based limits and analyzing detection prospects with advanced interferometers.

Findings

WMAP bounds exceed COBE bounds on gravitational wave spectrum

Bounds remain below frequencies detectable by ground-based antennas

Longer integration times are needed for potential detection with advanced LIGO

Abstract

The cosmological bound of the stochastic background of gravitational waves is analyzed with the aid of the WMAP data, differently from lots of works in literature, where the old COBE data were used. From our analysis, it will result that the WMAP bounds on the energy spectrum and on the characteristic amplitude of the stochastic background of gravitational waves are greater than the COBE ones, but they are also far below frequencies of the earth-based antennas band. At the end of this letter a lower bound for the integration time of a potential detection with advanced LIGO is released and compared with the previous one arising from the old COBE data. Even if the new lower bound is minor than the previous one, it results very long, thus for a possible detection we hope in the LISA interferometer and in a further growth in the sensitivity of advanced projects.