1. GEO600 Status Update Harald Lück Hannover, April 2005

3. S4 Feb 22nd – March 23rd Two manned shifts/day (5-21 UTC), 1 ‚expert on duty‘ 8-8UTC Overnight SMS alarms to ‚expert on duty‘ –Locking status –DAQS (DCUs running, frame making, timing, calibration) –Temperatures –Vacuum Instrumental duty cycle 97.5%

4. ‚Typical‘ S4 Sensitivity Violin modes N * 50Hz Calibration lines Laser power PR, E highV, EN lowV MC Turbo SR h [1/sqrt(Hz)]

5. S4 Glitchy periods within the first week

7. Glitches occurred mainly during seismically quiet times

8. Curing the glitches (temporarily) (What is a jump? :-)

9. Intermediate Mass of Mounting Unit 3 probably touched coil holder frame

11. After ‚unstickíng‘ MU3 by rotating it

12. BLRMS during S4

13. Strange sine gaussian glitches h [1/sqrt(Hz)]

14. Strange sine gaussian glitches ctnd.

16. Calibration of GEO600 Time-domain calibration method Optimization routine quasi-continuously estimates parameters of optical response –Calibration lines give known differential arm- length disturbance –These points are fit to a model Update rate is 1Hz

17. Michelson Servo Error Points P Q

18. On-line optical TF measurements actuator optical CAL P and Q

19. Optical&Electronic Gain

20. Calibration

21. Calibrated EP Quadrature Signals h [1/sqrt(Hz)]

22. Combining h P (t) and h Q (t) – III Create filters from noise floor estimates h(t) = Pfilter{h P (t)} + Qfilter{h Q (t)}  QQ  PP  PQ

23. Combining h P (t) and h Q (t) – results Get the best of h P and h Q plus a little extra! h [1/sqrt(Hz)]

24. Steps after S4 PR fast autoalignment, Unity gain ~4-5Hz √ Improve seismic long. FF & long.->IM tilt FF Increase PR factor by changing PR mirror 1.35% -> 0.1% Change laser, increase power to ~12W, i.e. ~5W @ MPR Lock interferometer with ~7kW internal power