1. Martin Hewitson Overview of DC work

2. GEO DC workshop June 20042 DC work Noise characterisation Noise projections, noise sources, noise couplings Calibration Production of h(t) and validation Detector operation Environmental effects, losses of lock, drifts and alignment control studies, long term effects Data characterisation Glitch rates, glitch coincidences Sensitivity fluctuations Non-stationarity Source sensitivity Detector group Analysis groups

3. GEO DC workshop June 20043 Noise characterisation Noise projections Try to understand limiting noise sources Noise sources Lines, broad-band features Do these limit CW searches? Noise couplings Transfer functions from signal X to detector output Time-variable? Significant? Leads to instrumental vetoes (see previous talks by Ken)

4. GEO DC workshop June 20044 Calibration Production of h(t) See calibration talk – not repeated here Validation Validation group Need independent ESD calibration Need study of subtle artifacts From inverse optical-response filtering From up/down-sampling … Can the  2 help as a data quality indicator?

5. GEO DC workshop June 20045 Detector operation Environmental effects Temperature dependences, seismic noise, wind… Studying losses of lock Operation and understanding of monitors Control room monitors GEO Summary pages Operational tasks Daily checks during science runs Are alignment drifts near end of range? Is sensitivity ‘normal’? …

6. GEO DC workshop June 20046 Data characterisation Glitch rates and coincident glitches Is the glitch rate ‘too high’ for effective burst searches? Time and frequency variance of glitch rate Sensitivity fluctuations Non-stationary behaviour Do we have a measure/monitor for this? Who cares? (Gaussianity of individual frequency bins) Source sensitivity Monitors for each search We have inspiralMon only; do we need others?

7. GEO DC workshop June 20047 Summary DC work remains important Need task-driven DC work Answer questions that exist Clearer understanding of who should do which work Detector group work, analysis group work, or both? More involvement/feedback from analysis groups (?)