First locking of the Virgo central area interferometer with suspension hierarchical control

Search ScienceDirect Advanced Outline Abstract PACS Keywords 1. Introduction 2. The Virgo central area interferometer 3. Hierarchical control implementation 4. Conclusion Acknowledgements References Figures (8) Fig. 1. Scheme of the CITF operated in the Michelson configuration Fig. 2. Scheme of the Virgo Superattenuator chain: in the CITF the feedback is exerted… Fig. 3. Block diagram of the control loop of the IP, comprising the top-stage feedback… Fig. 4. Open loop transfer functions of the feedback to the top-stage of the Inverted… Fig. 5. Sensitivity curve during a 72 h continuous run with feedback to the top-stage… Fig. 6. Effect of the feedback to the top-stage of the Inverted Pendulum on the WM… Elsevier Astroparticle Physics Volume 20, Issue 6, March 2004, Pages 629-640 Astroparticle Physics First locking of the Virgo central area interferometer with suspension hierarchical control Author links open overlay panelVirgo CollaborationFAcerneseaPAmicobNArnaudcDBabuscidRBarilléeFBaroneaLBarsottifMBarsugliacFBeauvillegM.ABizouardcCBoccarahFBonduiLBosibCBradaschiafLBraccijSBraccinifABrilleti…MYvertg Show more https://doi.org/10.1016/j.astropartphys.2003.10.003Get rights and content Abstract Operation of the central portion of Virgo as a simple 6 m Michelson interferometer has given the first demonstration of the possibility to control an interferometer suspended from Virgo full scale multistage seismic attenuators using information derived from the interferometer locking signal. A special role in the control is played by the first stage of these suspensions, an inverted pendulum: besides its seismic preisolation action, this stage has positioning dynamics of several mm, and it allows to exert a very low frequency control at the upper level of the suspension using the interferometer fringe signal. The application of this feedback to the top-stage of the suspension allows corrections of drifts, such as tidal ones, at a stage of the suspension where a large dynamic range in displacements is available, without introducing noise at the level of the mirror, resulting in a significant reduction of the lock keeping force applied directly on the mirror at the lowest stage of the attenuator.