Gravitational wave bursts from cosmic strings

TL;DR

The GW bursts discussed here might be accompanied by gamma ray bursts and be detectable by the planned GW detectors LIGO/VIRGO and LISA for string tensions as small as G&mgr; approximately 10(-13).

Abstract

Cusps of cosmic strings emit strong beams of high-frequency gravitational waves (GW). As a consequence of these beams, the stochastic ensemble of gravitational waves generated by a cosmological network of oscillating loops is strongly non Gaussian, and includes occasional sharp bursts that stand above the rms GW background. These bursts might be detectable by the planned GW detectors LIGO/VIRGO and LISA for string tensions as small as $G μ\sim 10^{-13}$. The GW bursts discussed here might be accompanied by Gamma Ray Bursts.

Figures (2)

• Figure 1: Gravitational wave amplitude of bursts emitted by cosmic string cusps in the LIGO/VIRGO frequency band, as a function of the parameter $\alpha = 50 G \mu$. [In a base-$10$ log-log plot.] The horizontal dashed lines indicate the one sigma noise levels (after optimal filtering) of LIGO 1 (initial detector) and LIGO 2 (advanced configuration).The short-dashed line indicates the rms amplitude of the stochastic GW background.
• Figure 2: Gravitational wave amplitude of bursts emitted by cosmic string cusps in the LISA frequency band, as a function of the parameter $\alpha = 50 G \mu$. [In a base-$10$ log-log plot.] The short-dashed curve indicates the rms amplitude of the stochastic GW background. The lower long-dashed line indicates the one sigma noise level (after optimal filtering) of LISA.