GEO600 Status UpdateHarald LckHannover, April 2005

S4Feb 22nd March 23rdTwo manned shifts/day (5-21 UTC), 1 expert on duty 8-8UTCOvernight SMS alarms to expert on dutyLocking statusDAQS (DCUs running, frame making, timing, calibration)TemperaturesVacuumInstrumental duty cycle 97.5%

Typical S4 Sensitivityh [1/sqrt(Hz)]

S4Glitchy periods within the first week

Glitches occurred mainly during seismically quiet times

Curing the glitches(temporarily)

(What is a jump? :-)

Intermediate Mass of Mounting Unit 3 probably touched coil holder frame

After unstickng MU3by rotating it

BLRMS during S4

Strange sine gaussian glitchesh [1/sqrt(Hz)]

Strange sine gaussian glitches ctnd.

Strange sine gaussian glitches ctnd.

Calibration of GEO600Time-domain calibration methodOptimization routine quasi-continuously estimates parameters of optical responseCalibration lines give known differential arm-length disturbanceThese points are fit to a modelUpdate rate is 1Hz

Michelson Servo Error PointsPQ

On-line optical TF measurementsactuatorCALP and Q

Optical&Electronic Gain

Calibration

Calibrated EP Quadrature Signalsh [1/sqrt(Hz)]

Combining hP(t) and hQ(t) IIICreate filters from noise floor estimatesh(t) = Pfilter{hP(t)} + Qfilter{hQ(t)}sQQsPPsPQ

Combining hP(t) and hQ(t) resultsGet the best of hP and hQ plus a little extra!h [1/sqrt(Hz)]

Steps after S4PR fast autoalignment, Unity gain ~4-5Hz

Improve seismic long. FF & long.->IM tilt FFIncrease PR factor by changing PR mirror 1.35% -> 0.1%Change laser, increase power to ~12W, i.e. ~5W @ MPRLock interferometer with ~7kW internal power

TF fluctuates and depends on tuning