Towards a Design Study Proposal for a 3rd Generation Interferometric Gravitational- wave Detector Harald Lück London, October 26th 2006

Harald Lück, London October 2006 Overview Keywords: 30km beam tube, 10 MW power, underground, cryogenics, squeezing, QND Countries involved: France, Germany, Great-Britain, Italy, Netherlands, Spain, et al. 11/2006 – 03/2007: Preparation of a Design Study Proposal by WG3 1st stage (2008 – 2010 ): Conceptual design study - Define aims of detector - Topology and site issues - Which technologies to use 2nd stage ( ): more detailed technical and engineering Design Study

Harald Lück, London October 2006 On the Path to GW Astronomy Credit: M.Punturo LIGO 2005 AURIGA 2005 Advanced LIGO/Virgo (2013) Third generation ITF Virgo Design GEO-HF 2009 Virgo+ 2008

Harald Lück, London October 2006 Amended Proposal for a DECISION OF THE EUROPEAN PARLIAMENT AND THE COUNCIL concerning the 7th framework programme of the European Community for research, technological development and demonstration activities ( ) Brussels, Article 4 Maximum overall amount and shares assigned to each programme 1. The maximum overall amount for Community financial participation in this seventh Framework Programme shall be EUR million. That amount shall be distributed among the activities and actions referred to in paragraphs 2 to 6 of Article 2 as follows (in EUR million): Cooperation % Ideas % People % Capacities % Non-nuclear actions of the Joint Research Centre % Amended Original Cut

Harald Lück, London October %About 1780Total [M€] About 3% ~ 50 … 3. Support measures … Risk Sharing Finance Facility … 2.3Construction : support to the implementation phase … 2.2Construction: support to the preparatory phase About 1/3 ~ …2.1Design studies 2. Support to new research infrastructures … 1.2ICT based e-Infrastructures … 1.1.1Integrating Activities (targeted) More than 60% >1100 … 1.1.1Integrating Activities (bottom-up) 1. Support to existing research infrastructures % Grand Total [M€] TotalActivitySub-part Orientations towards a Work Programme for the specific programme for research, technological development and demonstration: "Capacities" Research Infrastructures ( ) 9 September 2006

Harald Lück, London October 2006 About 1780Total 160 Contribution between 2009 and 2013 to the Risk Sharing Finance Facility …Direct grants for the construction phase …Support Measures …ICT based e-Infrastructures …Integrating Activities Call 4 (late 2011) …Support Measures …Construction – preparatory phase …Design studies …ICT based e-Infrastructures …Integrating Activities Call 3 (late 2009) …Support Measures …ICT based e-Infrastructures …Integrating Activities Call 2 (later in 2007) 40Contribution in 2007 to the Risk Sharing Facility …Support Measures …Construction – preparatory phase …Design studies …ICT based e-infrastructures Call 1 (early 2007) Indicative budget (M€) ActivityCall N° Conceptual Study (basis for ESFRI Roadmap) Detailled technological Study

Harald Lück, London October 2006 GW 3rd Gen. - DS financial / manpower scale ~ 7 M€ for 3 years ~ 7 M€ for 3 years -> 20 scientists + travel, administration etc. Assume 6 countries -> 3 / country Assume 6 countries -> 3 / country

Harald Lück, London October 2006 DS Topics Scientific goals achievable Scientific goals achievable Topology Topology –of single detector (e.g. triangular vs L-shaped Michelson) –Optimum size –European network vs single bigger detector (depends on other potential 3rd generation detectors located elsewhere); balance sensitivity against improved angular resolution –Coordinate with LIGO, what are LIGO plans concerning 3rd generation detector(s)? Under- / over-ground Under- / over-ground –Newtonian: how important is it for astr. observations? Only frequencies ~<10Hz will be affected –Control aspects (low seismic makes all control aspects easier) –Can similarly low seismic / Newtonian subtraction be achieved over ground with comparable financial efforts? Sensitivity curve: broadband vs narrowband depending on sources studied and sensitvity options Sensitivity curve: broadband vs narrowband depending on sources studied and sensitvity options

Harald Lück, London October 2006 DS Topics (ctnd) Reduction of fundamental noises: Reduction of fundamental noises: –Shot noise Lasers (power limits envisaged for conventional and 1.55µm) Lasers (power limits envisaged for conventional and 1.55µm) Conventional vs. Diffractive Conventional vs. Diffractive Squeezing incl. all options Squeezing incl. all options QND methods QND methods –Radiation pressure noise reduction –Thermal noise Low dissipation suspensions and seismic isolation systems Low dissipation suspensions and seismic isolation systems Materials, incl. 1.55µm Materials, incl. 1.55µm Coating issues (doping, optimized thicknesses, new techniques [e.g. waveguide], composite [2 part] mirrors…), assess what can be reached on the timescales envisaged as input for other groups, e.g. broadband vs narrowband. Coating issues (doping, optimized thicknesses, new techniques [e.g. waveguide], composite [2 part] mirrors…), assess what can be reached on the timescales envisaged as input for other groups, e.g. broadband vs narrowband. Low noise cryogenics incl. wavelength issues; what is possible, how much do we gain? Low noise cryogenics incl. wavelength issues; what is possible, how much do we gain? Beam shape Beam shape –Gaussian beams –Mesa beams –Higher order LG modes High power problems High power problems –Thermal –(parametric) instabilities Follow up of new developments Follow up of new developments –Investigate benefits –Study feasibility for 3rd generation detector (readiness, financial etc.)

Harald Lück, London October 2006 Timeline The preparation of the proposal will be managed within ILIAS-WG3 Discuss the start of proposal work at this meeting Realize a skeleton version of the Design Study proposal within two months, ie in Call an open meeting of WG3 to look for (new) collaborators Distribute writing workload onto subgroups Prepare a first draft version until end of February. Call for Proposals closes about middle of April.