Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Characterization of LIGO Input Optics University of Florida Caltech MIT Thomas Delker Guido Mueller Malik Rakhmanov David Reitze Haisheng Rong Qi-ze Shu David Tanner Sanichio Yoshida Jordan Camp Bill Kells Nergis Mavalvala David Ottaway Daniel Sigg Stan Whitcomb Rana Adhikari Peter Fritschel Mike Zucker Presented by Haisheng Rong at LSC Meeting 7 Hanford, 15-17 August 2000 Laser Interferometer Gravitational-wave Observatory 1 Input Optics System Primary Functions of the IO System Conditioning of the PSL output Frequency, Intensity and beam pointing stability Filter high-order modes Mode matching and beam delivery Optical isolation RF sidebands generation for IFO sensing Laser Interferometer Gravitational-wave Observatory 2 Input Optics Components IFO Laser Interferometer Gravitational-wave Observatory 3 IO System Interfaces Laser Interferometer Gravitational-wave Observatory 4 Status of the IO System LHO 2k » » » » Operational since 08/99 Major characterization measurements finished Integration with 2k IFO arm cavity successful Modification and realignment 04/00 – 05/00 LLO 4k » Mode cleaner locked in 03/00 » Characterization and improvement 03/00 – 06/00 » IO realignment 06/00 – 08/00 LHO 4k » Installation started 07/00 Laser Interferometer Gravitational-wave Observatory 5 Characterization Measurements Mode Cleaner Length » Measured with RF resonant side band detuning method. » Uncertainty / Drift ~ 3ppm (50 mm) » Position Accuracy < 1mm MC Transmission » 0.98 0.05 Mode Matching into the 2k Arm Cavity » Power Coupling: 95%-98% Laser Interferometer Gravitational-wave Observatory 6 Characterization Measurements MC Output Beam Pointing Stability » Long-term drift ~4mrad/hr » Beam jitter 10 -10 rad/rtHz at f >20Hz Laser Interferometer Gravitational-wave Observatory 7 Characterization Measurements MC cavity linewidth measurements Ringdown Transfer function Laser Interferometer Gravitational-wave Observatory 8 Characterization Measurements MC linewidth measurement results Laser Interferometer Gravitational-wave Observatory 9 Characterization Measurements Internal Q’s of MC mirrors Laser Interferometer Gravitational-wave Observatory 10 MC - a sensitive analyzer cavity Frequency noise of the PSL Laser Interferometer Gravitational-wave Observatory 11 Effect of the vertical mirror motion PSD of MC length control signal F = 0.62 mrad F=0 F: Angle of MC plane wrt. horizontal Laser Interferometer Gravitational-wave Observatory 12 Frequency noise of MC output Frequency noise measured with 2k FP arm cavity Laser Interferometer Gravitational-wave Observatory 13 Coming up Lock MC at designed input power » Scattered laser light interacts with suspension local sensors, causing angular instability » Solution – Phase sensitive detection (coherent sensor) – New shadow sensors Laser Interferometer Gravitational-wave Observatory 14