1. GWA-WG1 G.Losurdo – INFN Florence H.Grote – AEI Hannover on behalf of WG1

2. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 2 WG1 mission  Objectives –To speed up the commissioning and the characterization of Virgo and GEO by means of a deeper collaboration between the two teams –To develop common methods of characterization of interferometric GW detectors to be applied to Virgo and GEO –To provide inputs for establishing priorities for short term improvements of the existing interferometric detectors on the base of the Virgo and GEO characterization  Activity started in 2004 (first meeting in July 2004)  Many progress in 2.5 years, but the commissioning of Virgo and GEO is not over. WG1 remains a precious environment for exchanging expertise

3. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 3 S.Hild H.Grote (co-chairman) H.Lueck J.Smith A.Freise M.Barsuglia H. Heitmann P.La Penna G.Losurdo (co-chairman) L.Taffarello M.Visco Not a closed group: we invite many people involved in commissioning to attend and talk GEO600 Virgo Bars The group

4. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 4 Meetings held so far 1st meeting1st meeting, Cascina, Jul 7-8 2004 2nd meeting2nd meeting, Hannover, Sep 23-24 2004 3rd meeting3rd meeting, Cascina, Jan 24-26 2005 4th meeting4th meeting, Hannover, April 7-8 2005 5th meeting5th meeting, Telecon, Jul 14 2005 6th meeting6th meeting, Perugia, Sep19-20 2005 7th meeting7th meeting, Hannover, Dec 12 2005 8th meeting8th meeting, Frascati, Mar 20-21 2006 9th meeting9th meeting, Potsdam, Jul 21-22 2006 10th meeting, Cascina, Nov 13-14 2006

5. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 5 GEO/Virgo commissioning progress GEO: last 6 months In science run (S5, 24/7) Virgo: 4 months to upgrade the input bench

6. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 6 WG1: 4-years execution plan Annual report Recommandations report for short term improvements GEO/Virgo joint noise characterization YEAR 4 07-08 Annual report GEO/Virgo joint noise characterization Implementation of common characterization algorithms YEAR 3 06-07 Annual report Recommandations report for short term improvements GEO/Virgo joint noise characterization Development of common characterization algorithms YEAR 2 05-06 Annual report Working group set-up GEO/Virgo noise sources comparison YEAR 1 04-05 DELIVERABLESMILESTONES

7. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 7  Dec. 2005 – Hannover –Installation of the new injection bench and mode matching at Virgo –Alignment noise. Sources of high frequency noise –Power line harmonics. Magnetic couplings to test mass motion  Mar. 2006 – Frascati –Suspension control issues –Special invited talk: “Measurements of small forces at very low frequencies” –Tools for noise analysis –The “owl” noise at GEO – brainstorming  Jul. 2006 - Potsdam –Alignment noise –Automation issues –Glitch measurement and removal –Thermal lensing and simulation tools WG1: last year meetings content

8. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 8 3 rd year milestones GEO/Virgo joint noise characterization Implementation of common algorithms

9. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 9 GEO data read with Virgo dataDisplay A.Freise

10. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 10 Virgo data to be read with GEO data viewer J.Smith, M.Hewitson Features: Time-series Spectrum (ASD, AS, PSD, PS) Coherence Transfer function Spectrogram Heterodyne Bicoherence IIR filtering (highpass, lowpass, bandpass, pole-zero) Resampling  Can read GEO, Virgo, LIGO frames  Install as test software at Virgo in Nov.

11. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 11 Noise coupling estimated primarily with formulas/models in Virgo, measurement in GEO. The projects can learn from each other. Laser power noise in Virgo/GEO J.Smith, G.Vajente

12. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 12 GEO glitch monitor J.Smith  Finds and parameterizes excess power events. – DB mining allows coincident analysis, etc.  This is the most useful glitch tool used in GEO. – Has led to numerous reductions in glitches.  Tested/debugged for about 6 yrs. – Parameter estimation tested and tuned with injections and real events. – Saves re-inventing the wheel !!  Might be useful for Virgo

13. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 13  Online computation of band-limited RMS and line identification  Offline analysis –Time series –Spectral analysis –Coherence with interferometer channels –Identification of non-stationarity sources  Might be useful for GEO Time series SpectraCoherences Monitor of non-stationary noise G.Vajente

14. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 14 Noise budget Noise projections and automated noise budget now used in both experiments. GEO uses almost entirely measured transfer functions Virgo uses also modelled TFs

15. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 15 Special activities A few parallel projects have been carried on within the WG1 framework, dealing with commissioning-related topics:  The windmills project  The beam centering project  The alignment optimization project  The joint noise characterization project (talk by J.Smith) BEAM CENTERING 1st meeting1st meeting, Napoli-Cascina, June 10-14, 2005 ALIGNMENT 1st meeting1st meeting, Birmingham, August 2006 WINDMILLS 1st telecon1st telecon, May 12, 2005 Team meetingTeam meeting, Cascina, 7-9 June 2005 Seismic surveySeismic survey, GEO600 site, July 25-29 2005 2nd telecon:2nd telecon: August 25, 2005 JOINT NOISE CHARACTERIZATION 1st report1st report, Cascina, September 11-22 2006 2nd report, Cascina, October 16-20, 2006

16. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 16 The Windmills project  Costruction of two windmills stations near Virgo proposed. Concern for seismic disturbance  The wind park next to GEO600: chance to study the windmills seismic wave field in a soft soil similar to the Virgo one.  Seismic survey on GEO600 site using two stations run in coincidence  Built a model of noise spectral composition and soil attenuation used to predict effects of the wind parks at Virgo, and define a safety distance of 5km from Virgo buildings  Positive reaction of both windmill companies, which modified projects layout to comply with our request.  Joint VIRGO-GEO600 document: VIR-NOT-PIS-1390-317 (I.Fiori L.Giordano S.Hild G.Losurdo E.Marchetti G.Mayer F.Paoletti)

17. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 17 The beam centering project  Centering of beam used for wavefront sensing on the quadrants is essential for the robustness of the alignment system  Virgo quadrants are centered with a low bandwidth (<0.3 Hz) control –Not enough to reduce rms considerably –Noisy system  GEO uses a commercial galvanometer scanner with custom mechanics and electronics.  Succesfully tested on Virgo: very good suppression of beam fluctuations Galvo off Galvo on R.De Rosa, L. Di Fiore, H.Grote, H.Heitmann, J.Marque,

18. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 18 The alignment optimization project  Sensing matrix optimization –Use the distribution of the matrix’ row vectors in the system's parameter space. Compute the separation of the diode signals in the space of the mirror angular movements.  Controllability: –Study of the dependence of the controllability of a simple system (a FP cavity using the Ward and the Anderson technique) on the parameters of the optical readout in order to validate and check the performance the chosen test method  Alignment noise propagation in Virgo under study VIRGO configuration : Result of the study on the controllability on a complex configuration as the VIRGO alignment system. The minimum separation between the 'best' sub-set of signal vectors is shown as a function of Gouy and demodulation phase (for the NE diodes). The chosen alignment control system can thus control all the required degrees of freedom and it can improved by tuning the parameters of the optical readouts. A.Freise, M.Mantovani

19. ILIAS GWA Annual Meeting - London, Oct 26th, 2006 G.Losurdo – INFN Firenze 19 Conclusive remarks  WG1 still very useful for the commissioning of Virgo and GEO  Meetings focused on noise hunting  Beside ordinary meetings, a set of “parallel” projects spread out of WG1  A fellowship for Virgo-GEO joint noise characterization has been granted within WG1: precious to fulfill the last milestones of the 4-years project