Status of GEO 600 Benno Willke for the

Status of GEO 600 Benno Willke for the GEO 600 team ESF Exploratory Workshop Perugia, September 2005

ESF 05 / GEO, B. Willke

container cluster 2005 Workshop Central Building Offices Bathrooms Control Room / Visitor Center ESF 05 / GEO, B. Willke

Tube / Trench ESF 05 / GEO, B. Willke

Clean Room / Control Room ESF 05 / GEO, B. Willke

Triple Pendulum Suspension ESF 05 / GEO, B. Willke

Thermal Noise / Monolithic Suspension Weld Silicate (Hydroxy. Catalysis) Bonding ESF 05 / GEO, B. Willke

reaction pendulum ESF 05 / GEO, B. Willke

GEO 600 – optical layout interferometer with „dual recycling“ modecleaner 12 W Laser detektor ESF 05 / GEO, B. Willke

Dual Recycling Length Control ESF 05 / GEO, B. Willke

Michelson length control < 0. 1 Hz < 10 Hz > 10 Hz Reaction Pendulum: 3 coil-magnet actuators at intermediate mass, range ~ 100µm Electrostatic actuation on test mass bias 630 V, range 0 -900 V= 3. 5µm ESF 05 / GEO, B. Willke

Alignment Control 4 degrees of freedom at MC 1 +4 at MC 2 +4 at MI (common mode) +2 at MI (differential mode) +2 at Signal-Recycling cavity Alignment Control 16 + 20 = 36 differential wave-front sensing spot position control ESF 05 / GEO, B. Willke

GEO 600 design sensitivity ESF 05 / GEO, B. Willke

Evolution of the GEO 600 Sensitivity ESF 05 / GEO, B. Willke

GEO 600 Duty Cycle date run name duty cycle longest lock Jan 2002 E 7 75% 3 h 40 min Aug 2002 S 1 98% 121 h Nov 2003 Jan 2004 S 3 -I (7 days) S 3 -II(14 days) 95% 98% 95 h Aug 2004 – Jan 2005 over night runs (51 days) 94% Mar 2005 S 4 97% 52 h ESF 05 / GEO, B. Willke

S 4 § Feb 22 nd – March 23 rd, 708 hours § Two manned shifts/day (5 -21 UTC), 1 „Expert-On-Duty“ 8 -8 UTC § Fully automated overnight shifts; SMS alarms to ‚E-O-D‘ § § Locking status DAQS (DCUs running, frame making, timing, calibration) Temperatures Vacuum § Instrumental duty cycle 97. 5%, 95% w/o noisy period, 72%>10 h § Longest lock 52 h ESF 05 / GEO, B. Willke

detector characterization § Sensitivity § Min/max spectrum of h(t) § 15 BLRMS of h(t) § Inspiral monitor § Spectrogram of h(t) § Calibration § Data quality § Chi 2 § Calibration parameters § Bursts (HACRmon) § Time frequency distribution § SNR distribution § Duration § Bandwidth § Lines (Linemon) § Line cataloguing § Harmonic identification § Sideband identification ESF 05 / GEO, B. Willke

Typical S 4 Sensitivity ESF 05 / GEO, B. Willke

Calibration ESF 05 / GEO, B. Willke

On-line optical TF measurements P and Q CAL actuator optical h ESF 05 / GEO, B. Willke

Calibration radiation pressure calibrator ? ESF 05 / GEO, B. Willke

Photon Pressure Calibrator Wavelength: 1035 nm @ 20°C Max. power: 1. 4 W, FWHM= 0. 66 nm Good agreement with ESD calibration ESF 05 / GEO, B. Willke

Optical Gain ESF 05 / GEO, B. Willke

h [1/sqrt(Hz)] Calibrated EP Quadrature Signals ESF 05 / GEO, B. Willke

Combining h. P(t) and h. Q(t) – results h [1/sqrt(Hz)] Get the best of h. P and h. Q plus a little extra! ESF 05 / GEO, B. Willke

increase of power recycling factor Michelson Interferometer Mode Cleaners 1500 W (typ. ) 2000 W (max) at Beam Splitter Laser 10 W 5 W 1. 6 W T=0. 09% Power Recycling Cavity: ~40 m. W Mode matching >85% Finesse 8300 Linewidth 30 Hz Output Mode Cleaner 4/0. 09%*1. 6 = 7000 ESF 05 / GEO, B. Willke

Thermal lensing in BS output mode pattern (PRMI) Directly after relocking f=20 km A few minutes after relocking f= 8 km → α≈0. 3 +/- 0. 05 ppm/cm ESF 05 / GEO, B. Willke

GEO 600 design sensitivity ESF 05 / GEO, B. Willke

Tuning signal recycling to 300 Hz § lock acquisition at 5 k. Hz § tuning needs to adjust of 6 parameters (lookup table) § improved input file for simulations and how to transfer results to experiment § achieved downtuning to 200 Hz § MI AA instability could be fixed ESF 05 / GEO, B. Willke

Interferometer Readout - Sidebands mirror laser phase modualtor beam splitter mirror photo detector ESF 05 / GEO, B. Willke

Schnupp – Modulation mirror laser phase modualtor beam splitter mirror photo detector ESF 05 / GEO, B. Willke

Gravitational Wave Side Bands mirror laser phase modualtor beam splitter mirror photo detector ESF 05 / GEO, B. Willke

Detuned Signal Recycling mirror laser phase modualtor beam splitter mirror photo detector ESF 05 / GEO, B. Willke

Unbalanced Sidebands PRC 72*D ( 119*D (1. 26 k. Hz) 72*D ( 765 Hz) 119* D (1. 26 k. Hz) SRC broadband 1. 86 k. Hz 2. 2 k. Hz 2. 3 k. Hz 1. 1 k. Hz SRC detuned to 1. 1 k. Hz -119 * f PRC carrier MI-sidebands -72 * f PRC SR-sidebands broadband 0 SR-sidebands 1. 1 k. Hz detuned 72 * f PRC 119 * f PRC SR-sidebands 2 k. Hz detuned ESF 05 / GEO, B. Willke

Signal Recycling digital § digital loop allows for steep filter § noise contribution reduced by up to a factor of 200 ESF 05 / GEO, B. Willke

Sqrt circuits in MI loop ESD: F U^2 Sqrt circuits are necessary to give full linear force range for acquisition. Drawback: sqrt circuits are noisy 1µV/sqrt(Hz) (=100µV/sqrt(Hz) @ ESD) ESF 05 / GEO, B. Willke

MI loop whitening / dewhitening dewhiten Whitening right after mixer: zero 3. 5 Hz pole 35 Hz Dewhitening for both split passes dewhiten Passive dewhitening done in HV path (0 -1 k. V) dewhiten Whiten ESF 05 / GEO, B. Willke

sensitivity improvements since July ESF 05 / GEO, B. Willke

Evolution of the GEO 600 Sensitivity ESF 05 / GEO, B. Willke

Current vs. Design sensitivity ESF 05 / GEO, B. Willke

Non-stationary Noise ESF 05 / GEO, B. Willke

Near Future § finish commissioning § § § increase circulating power find source of optical losses in PR cavity increase MI loop gain between 1 -10 Hz improve RF circuitry optimize stability § join S 5 in overnight/weekend mode until commissioning is finished § fully join S 5 ESF 05 / GEO, B. Willke

ESF 05 / GEO, B. Willke