Building Bridges through Science

Science is ideally suited to connect people from different cultures and thereby foster mutual understanding. To promote international life science collaboration, we have launched "The Science Bridge" initiative. Our current project focuses on partnership between Western and Middle Eastern neuroscience communities

Calibration of the LIGO gravitational wave detectors in the fifth science run

The Laser Interferometer Gravitational Wave Observatory (LIGO) is a network of three detectors built to detect local perturbations in the spacetime metric from astrophysical sources. These detectors, two in Hanford, WA and one in Livingston, LA, are power-recycled Fabry-Perot Michelson interferometers. In their fifth science run (S5), between November 2005 and October 2007, these detectors accumulated one year of triple coincident data while operating at their designed sensitivity. In this paper, we describe the calibration of the instruments in the S5 data set, including measurement techniques and uncertainty estimation

Very low latency search for low mass compact binary coalescences in the LIGO S6 and Virgo VSR2 data

International audienceA very low latency search pipeline has been developed for the LIGO S6 and Virgo VSR2 science runs, targeting signals from coalescing compact binary systems with total mass from 2 to 35 solar masses. The goal of this search is to provide both single-detector triggers and multi-detector coincident triggers with a latency of a few minutes, the former for online detector monitoring and the latter to allow searching for electromagnetic counterparts to possible gravitational wave candidates. The features and current performance of this low latency search pipeline are presented

A gravitational wave observatory operating beyond the quantum shot-noise limit

Around the globe several observatories are seeking the first direct detection of gravitational waves (GWs). These waves are predicted by Einstein's general theory of relativity and are generated, for example, by black-hole binary systems. Present GW detectors are Michelson-type kilometre-scale laser interferometers measuring the distance changes between mirrors suspended in vacuum. The sensitivity of these detectors at frequencies above several hundred hertz is limited by the vacuum (zero-point) fluctuations of the electromagnetic field. A quantum technology--the injection of squeezed light--offers a solution to this problem. Here we demonstrate the squeezed-light enhancement of GEO600, which will be the GW observatory operated by the LIGO Scientific Collaboration in its search for GWs for the next 3-4 years. GEO600 now operates with its best ever sensitivity, which proves the usefulness of quantum entanglement and the qualification of squeezed light as a key technology for future GW astronomy