1. Soma Mukherjee, GWDAW7, Kyoto, Japan, 19/12/02, LIGO-G030166-00-Z1 Robust Detection of Noise Floor Drifts in Interferometric Data Soma Mukherjee Max Planck Institut fuer Gravitationsphysik Golm, Germany. GWDAW7, Kyoto, Japan, 19/12/02

2. Soma Mukherjee, GWDAW7, Kyoto, Japan, 19/12/02, LIGO-G030166-00-Z2 Motivation : Interferometric data has three components : Lines, transients, noise floor. Study of a change in any one of these without elimination of the other two will cause interference. Lines dominate. Presence of transients change the central tendency. “SLOW” nonstationarity of noise floor interesting in the analysis of several astrophysical searches, e.g. Externally triggered search.

3. Soma Mukherjee, GWDAW7, Kyoto, Japan, 19/12/02, LIGO-G030166-00-Z3 Methods : Running Median. Computation of : G(m)=V(Z t+m – Z t )/V(Z t+1 – Z t ) Z t : t th sample of a timeseries. m: Lag.

4. Soma Mukherjee, GWDAW7, Kyoto, Japan, 19/12/02, LIGO-G030166-00-Z4 Sequence : Low pass and resample Estimate spectral noise floor using Running Median Design FIR Whitening filter. Whiten data. Clean lines. Highpass. Compute Running Median of the squared timeseries. Construct Variograms. Thresholds set by Simulation.

5. Soma Mukherjee, GWDAW7, Kyoto, Japan, 19/12/02, LIGO-G030166-00-Z5

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11. Soma Mukherjee, GWDAW7, Kyoto, Japan, 19/12/02, LIGO-G030166-00-Z11

12. Soma Mukherjee, GWDAW7, Kyoto, Japan, 19/12/02, LIGO-G030166-00-Z12

13. Soma Mukherjee, GWDAW7, Kyoto, Japan, 19/12/02, LIGO-G030166-00-Z13

14. Soma Mukherjee, GWDAW7, Kyoto, Japan, 19/12/02, LIGO-G030166-00-Z14

15. Soma Mukherjee, GWDAW7, Kyoto, Japan, 19/12/02, LIGO-G030166-00-Z15

16. Soma Mukherjee, GWDAW7, Kyoto, Japan, 19/12/02, LIGO-G030166-00-Z16

17. Soma Mukherjee, GWDAW7, Kyoto, Japan, 19/12/02, LIGO-G030166-00-Z17

18. Soma Mukherjee, GWDAW7, Kyoto, Japan, 19/12/02, LIGO-G030166-00-Z18

19. Soma Mukherjee, GWDAW7, Kyoto, Japan, 19/12/02, LIGO-G030166-00-Z19 Future : `To be run on full S1 data (LIGO/GEO). More quantification of the Running Median and variogram. To be tested on bandlimited data. Automation and incorporation in the DCR underway.