The merger rate of black hole binaries inferred from the detections in the first Advanced LIGO science run implies that a stochastic background produced by a cosmological population of mergers will ...likely mask the primordial gravitational wave background. Here we demonstrate that the next generation of ground-based detectors, such as the Einstein Telescope and Cosmic Explorer, will be able to observe binary black hole mergers throughout the Universe with sufficient efficiency that the confusion background can potentially be subtracted to observe the primordial background at the level of Ω_{GW}≃10^{-13} after 5 years of observation.
The Laser Interferometer Gravitational wave Observatory (LIGO) is a network of first generation interferometric detectors aiming to make the first direct observations of gravitational waves. Progress ...in the commissioning of the detectors has brought them within a factor of two of their design sensitivity near 150 Hz during the most recent science run of the instruments in March of 2005. Further improvements took place in the instruments since then and operating them at design sensitivity together with high duty cycle is expected by the end of 2005. This Letter surveys the status of the LIGO instruments and discusses results and prospects of direct detections of gravitational waves bursts.
Hardware injections are simulated gravitational-wave signals added to the Laser Interferometer Gravitational-wave Observatory (LIGO). The detectors’ test masses are physically displaced by an ...actuator in order to simulate the effects of a gravitational wave. The simulated signal initiates a control-system response which mimics that of a true gravitational wave. This provides an end-to-end test of LIGO’s ability to observe gravitational waves. The gravitational-wave analyses used to detect and characterize signals are exercised with hardware injections. By looking for discrepancies between the injected and recovered signals, we are able to characterize the performance of analyses and the coupling of instrumental subsystems to the detectors’ output channels. This paper describes the hardware injection system and the recovery of injected signals representing binary black hole mergers, a stochastic gravitational wave background, spinning neutron stars, and sine-Gaussians.
PDF
