We present the preliminary results for an experiment that aims to perform direct measurements of suspension thermal noise. The experiment is based on a niobium flexure membrane approximately 200 µm ...thickness that is operated as a stable inverted pendulum. A 0.25 g mirror suspended by this flexure membrane is used as the end mirror of a Fabry-Perot test cavity. This test cavity has a length of 12mm and a finesse of about 800. It is mounted at the lowest stage of a quadruple cascaded pendulum suspension, enclosed in a high-vacuum envelope. The length of test cavity is stabilized with 1Hz bandwidth to a Nd:YAG laser, which itself is stabilized with high bandwidth to the length of a suspended Zerodur reference cavity of finesse 6000.
The status of GEO 600 Grote, H; Allen, B; Aufmuth, P ...
Classical and quantum gravity,
05/2005, Volume:
22, Issue:
10
Journal Article, Conference Proceeding
Gingin High Optical Power Test Facility Zhao, C; Blair, D G; Barrigo, P ...
Journal of physics. Conference series,
03/2006, Volume:
32, Issue:
1
Journal Article
Peer reviewed
Open access
The Australian Consortium for Gravitational Wave Astronomy (ACIGA) in collaboration with LIGO is developing a high optical power research facility at the AIGO site, Gingin, Western Australia. ...Research at the facility will provide solutions to the problems that advanced gravitational wave detectors will encounter with extremely high optical power. The problems include thermal lensing and parametric instabilities. This article will present the status of the facility and the plan for the future experiments.
Between 2007 and 2010 Virgo collected data in coincidence with the LIGO and GEO gravitational-wave (GW) detectors. These data have been searched for GWs emitted by cataclysmic phenomena in the ...universe, by non-axisymmetric rotating neutron stars or from a stochastic background in the frequency band of the detectors. The sensitivity of GW searches is limited by noise produced by the detector or its environment. It is therefore crucial to characterize the various noise sources in a GW detector. This paper reviews the Virgo detector noise sources, noise propagation, and conversion mechanisms which were identified in the three first Virgo observing runs. In many cases, these investigations allowed us to mitigate noise sources in the detector, or to selectively flag noise events and discard them from the data. We present examples from the joint LIGO-GEO-Virgo GW searches to show how well noise transients and narrow spectral lines have been identified and excluded from the Virgo data. We also discuss how detector characterization can improve the astrophysical reach of GW searches.
PDF
