The International Linear Collider Barry Barish ANL Colloquium 3-Jan-06 ANL Director's Colloquium2 Particle Physics Inquiry Based Science 1.Are there undiscovered principles of nature: New symmetries, new physical laws? 2.How can we solve the mystery of dark energy? 3.Are there extra dimensions of space? 4.Do all the forces become one? 5.Why are there so many kinds of particles? 6.What is dark matter? How can we make it in the laboratory? 7.What are neutrinos telling us? 8.How did the universe come to be? 9.What happened to the antimatter? from the Quantum Universe 3-Jan-06ANL Director's Colloquium3 Answering the Questions Three Complementary Probes Neutrinos as a Probe Particle physics and astrophysics using a weakly interacting probe High Energy Proton Proton Colliders Opening up a new energy frontier ( ~ 1 TeV scale) High Energy Electron Positron Colliders Precision Physics at the new energy frontier 3-Jan-06ANL Director's Colloquium4 Neutrinos Many Questions Why are neutrino masses so small ? Are the neutrinos their own antiparticles? What is the separation and ordering of the masses of the neutrinos? Neutrinos contribution to the dark matter? CP violation in neutrinos, leptogenesis, possible role in the early universe and in understanding the particle antiparticle asymmetry in nature? 3-Jan-06ANL Director's Colloquium5 Neutrinos The Future Long baseline neutrino experiments Create neutrinos at an accelerator or reactor and study at long distance when they have oscillated from one type to another. MINOS Opera 3-Jan-06ANL Director's Colloquium6 Why a TeV Scale e + e - Accelerator? Two parallel developments over the past few years ( the science & the technology) The precision information from LEP and other data have pointed to a low mass Higgs; Understanding electroweak symmetry breaking, whether supersymmetry or an alternative, will require precision measurements. There are strong arguments for the complementarity between a ~ TeV ILC and the LHC science. 3-Jan-06ANL Director's Colloquium7 Electroweak Precision Measurements What causes mass?? The mechanism Higgs or alternative appears around the corner 3-Jan-06ANL Director's Colloquium8 Accelerators and the Energy Frontier Large Hadron Collider CERN Geneva Switzerland 3-Jan-06ANL Director's Colloquium9 LHC and the Energy Frontier Source of Particle Mass The Higgs Field Discover the Higgs or variants or ??? fb -1 LEP FNAL 3-Jan-06ANL Director's Colloquium10 LHC and the Energy Frontier A New Force in Nature Discover a new heavy particle, Z Can show by measuring the couplings with the ILC how it relates to other particles and forces 3-Jan-06ANL Director's Colloquium11 This led to higher energy machines: Electron-Positron Colliders Bruno Touschek built the first successful electron-positron collider at Frascati, Italy (1960) Eventually, went up to 3 GeV ADA 3-Jan-06ANL Director's Colloquium12 But, not quite high enough energy . Discovery Of Charm Particles and 3.1 GeV Burt Richter Nobel Prize SPEAR at SLAC 3-Jan-06ANL Director's Colloquium13 The rich history for e + e - continued as higher energies were achieved DESY PETRA Collider 3-Jan-06ANL Director's Colloquium14 Electron Positron Colliders The Energy Frontier 3-Jan-06ANL Director's Colloquium15 Why e + e - Collisions ? elementary particles well-defined energy, angular momentum uses full COM energy produces particles democratically can mostly fully reconstruct events 3-Jan-06ANL Director's Colloquium16 The linear collider will measure the spin of any Higgs it can produce by measuring the energy dependence from threshold How do you know you have discovered the Higgs ? Measure the quantum numbers. The Higgs must have spin zero ! 3-Jan-06ANL Director's Colloquium17 What can we learn from the Higgs? Straight blue line gives the standard model predictions. Range of predictions in models with extra dimensions -- yellow band, (at most 30% below the Standard Model The red error bars indicate the level of precision attainable at the ILC for each particle Precision measurements of Higgs coupling can reveal extra dimensions in nature 3-Jan-06ANL Director's Colloquium18 New space-time dimensions can be mapped by studying the emission of gravitons into the extra dimensions, together with a photon or jets emitted into the normal dimensions. Linear collider Direct production from extra dimensions ? 3-Jan-06ANL Director's Colloquium19 BosonsFermions Virtues of Supersymmetry: Unification of Forces The Hierarchy Problem Dark Matter Is There a New Symmetry in Nature? Supersymmetry 3-Jan-06ANL Director's Colloquium20 Parameters for the ILC E cm adjustable from 200 500 GeV Luminosity Ldt = 500 fb -1 in 4 years Ability to scan between 200 and 500 GeV Energy stability and precision below 0.1% Electron polarization of at least 80% The machine must be upgradeable to 1 TeV 3-Jan-06ANL Director's Colloquium21 A TeV Scale e + e - Accelerator? Two parallel developments over the past few years (the science & the technology ) Two alternate designs -- warm and cold had come to the stage where the show stoppers had been eliminated and the concepts were well understood. A major step toward a new international machine requires uniting behind one technology, and then make a unified global design based on the recommended technology. 3-Jan-06ANL Director's Colloquium22 The JLC-X and NLC essentially a unified single design with common parameters The main linacs based on 11.4 GHz, room temperature copper technology. GLC GLC/NLC Concept 3-Jan-06ANL Director's Colloquium23 TESLA Concept The main linacs based on 1.3 GHz superconducting technology operating at 2 K. The cryoplant, is of a size comparable to that of the LHC, consisting of seven subsystems strung along the machines every 5 km. 3-Jan-06ANL Director's Colloquium24 CLIC Concept The main linac rf power is produced by decelerating a high- current (150 A) low- energy (2.1 GeV) drive beam Nominal accelerating gradient of 150 MV/m GOAL Proof of concept ~2010 Drive Beam Main Accelerator 3-Jan-06ANL Director's Colloquium25 SCRF Technology Recommendation The recommendation of ITRP was presented to ILCSC & ICFA on August 19, 2004 in a joint meeting in Beijing. ICFA unanimously endorsed the ITRPs recommendation on August 20, 2004 3-Jan-06ANL Director's Colloquium26 The ITRP Recommendation We recommend that the linear collider be based on superconducting rf technology This recommendation is made with the understanding that we are recommending a technology, not a design. We expect the final design to be developed by a team drawn from the combined warm and cold linear collider communities, taking full advantage of the experience and expertise of both (from the Executive Summary). 3-Jan-06ANL Director's Colloquium27 The Community Self-Organized Nov 13-15, 2004 3-Jan-06ANL Director's Colloquium28 Global Design Effort (GDE) February 2005, at TRIUMF, ILCSC and ICFA unanimously endorsed the search committee choice for GDE Director On March 18, 2005 Barry Barish officially accepted the position at the opening of LCWS 05 meeting at Stanford 3-Jan-06ANL Director's Colloquium29 Global Design Effort The Mission of the GDE Produce a design for the ILC that includes a detailed design concept, performance assessments, reliable international costing, an industrialization plan, siting analysis, as well as detector concepts and scope. Coordinate worldwide prioritized proposal driven R & D efforts (to demonstrate and improve the performance, reduce the costs, attain the required reliability, etc.) The GDE Plan and Schedule Global Design EffortProject Baseline configuration Reference Design ILC R&D Program Technical Design Expression of Interest to Host International Mgmt LHC Physics CLIC 3-Jan-06ANL Director's Colloquium31 GDE Begins at Snowmass 670 Scientists attended two week workshop at Snowmass GDE Members Americas 22 Europe 24 Asia 16 3-Jan-06ANL Director's Colloquium32 Designing a Linear Collider Superconducting RF Main Linac 3-Jan-06ANL Director's Colloquium33 GDE Organization for Snowmass WG1 LET bdyn. WG2 Main Linac WG3a Sources WG3b DR WG4 BDS WG5 Cavity GG1 Parameters GG2 Instrumentation GG3 Operations & Reliability GG4 Cost & Engineering GG5 Conventional Facilities GG6 Physics Options Technical sub-system Working Groups Global Group Provide input 3-Jan-06ANL Director's Colloquium34 rf bands: L-band (TESLA)1.3 GHz = 3.7 cm S-band (SLAC linac) GHz1.7 cm C-band (JLC-C)5.7 GHz0.95 cm X-band (NLC/GLC)11.4 GHz0.42 cm (CLIC)25-30 GHz0.2 cm Accelerating structure size is dictated by wavelength of the rf accelerating wave. Wakefields related to structure size; thus so is the difficulty in controlling emittance growth and final luminosity. Bunch spacing, train length related to rf frequency Damping ring design depends on bunch length, hence frequency Specific Machine Realizations Frequency dictates many of the design issues for LC RF Bands 3-Jan-06ANL Director's Colloquium35 Design Approach Create a baseline configuration for the machine Document a concept for ILC machine with a complete layout, parameters etc. defined by the end of 2005 Make forward looking choices, consistent with attaining performance goals, and understood well enough to do a conceptual design and reliable costing by end of Technical and cost considerations will be an integral part in making these choices. Baseline will be put under configuration control, with a defined process for changes to the baseline. A reference design will be carried out in I am proposing we use a parametric design and costing approach. Technical performance and physics performance will be evaluated for the reference design 3-Jan-06ANL Director's Colloquium36 The Key Decisions Critical choices: luminosity parameters & gradient 3-Jan-06ANL Director's Colloquium37 Making Choices The Tradeoffs Many decisions are interrelated and require input from several WG/GG groups 3-Jan-06ANL Director's Colloquium38 ILC Baseline Configuration Configuration for 500 GeV machine with expandability to 1 TeV Some details locations of low energy acceleration; crossing angles are not indicated in this cartoon. 3-Jan-06ANL Director's Colloquium39 Cost Breakdown by Subsystem Civil SCRF Linac 3-Jan-06ANL Director's Colloquium40 Approach to ILC R&D Program Proposal-driven R&D in support of the baseline design. Technical developments, demonstration experiments, industrialization, etc. Proposal-driven R&D in support of alternatives to the baseline Proposals for potential improvements to the baseline, resources required, time scale, etc. Develop a prioritized DETECTOR R&D program aimed at technical developments needed to reach combined design performance goals 3-Jan-06ANL Director's Colloquium41 TESLA Cavity 9-cell 1.3GHz Niobium Cavity Reference design: has not been modified in 10 years ~1m 3-Jan-06ANL Director's Colloquium42 How Costs Scale with Gradient? Relative Cost Gradient MV/m 35MV/m is close to optimum Japanese are still pushing for MV/m 30 MV/m would give safety margin C. Adolphsen (SLAC) 3-Jan-06ANL Director's Colloquium43 Superconducting RF Cavities High Gradient Accelerator 35 MV/meter km linear collider 3-Jan-06ANL Director's Colloquium44 Improved Cavity Shapes 3-Jan-06ANL Director's Colloquium45 Improved Fabrication 3-Jan-06ANL Director's Colloquium46 Improved Processing Electropolishing Chemical Polish Electro Polish 3-Jan-06ANL Director's Colloquium47 (Improve surface quality -- pioneering work done at KEK) BCPEP Several single cell cavities at g > 40 MV/m 4 nine-cell cavities at ~35 MV/m, one at 40 MV/m Theoretical Limit 50 MV/m Electro-polishing 3-Jan-06ANL Director's Colloquium48 Gradient Results from KEK-DESY collaboration must reduce spread (need more statistics) single-cell measurements (in nine-cell cavities) 3-Jan-06ANL Director's Colloquium49 Baseline Gradient 3-Jan-06ANL Director's Colloquium50 Large Grain Single Crystal Nb Material 3-Jan-06ANL Director's Colloquium51 The Main Linac Configuration Klystron 10 MW (alternative sheet beam klystron) RF Configuration 3 Cryomodules, each with 8 cavities Quads one every 24 cavities is enough 3-Jan-06ANL Director's Colloquium52 Other Features of the Baseline Electron Source Conventional Source using a DC gun 3-Jan-06ANL Director's Colloquium53 Other Features of the Baseline Positron Source Helical Undulator with Polarized beams Primary e - source e - DR Target e - Dump Photon Beam Dump e + DR Auxiliary e - Source Photon Collimators Adiabatic Matching Device e + pre- accelerator ~5GeV 150 GeV100 GeV Helical Undulator In By-Pass Line Photon Target 250 GeV Positron Linac IP Beam Delivery System 3-Jan-06ANL Director's Colloquium54 Damping Ring Options 3 Km 6 Km 3 or 6 km rings can be built in independent tunnels dogbone straight sections share linac tunnel Two or more rings can be stacked in a single tunnel 3-Jan-06ANL Director's Colloquium55 ILC Siting and Conventional Facilities The design is intimately tied to the features of the site 1 tunnels or 2 tunnels? Deep or shallow? Laser straight linac or follow earths curvature in segments? GDE ILC Design will be done to samples sites in the three regions North American sample site will be near Fermilab Japan and Europe are to determine sample sites by the end of 2005 3-Jan-06ANL Director's Colloquium56 1 vs 2 Tunnels Tunnel must contain Linac Cryomodule RF system Damping Ring Lines Save maybe $0.5B Issues Maintenance Safety Duty Cycle 3-Jan-06ANL Director's Colloquium57 Possible Tunnel Configurations One tunnel of two, with variants ?? 3-Jan-06ANL Director's Colloquium58 Americas Sample Site Design to sample sites from each region Americas near Fermilab Japan Europe CERN & DESY Illinois Site depth 135m Glacially derived deposits overlaying Bedrock. The concerned rock layers are from top to bottom the Silurian dolomite, Maquoketa dolomitic shale, and the Galena- Platteville dolomites. 3-Jan-06ANL Director's Colloquium59 Parametric Approach A working space - optimize machine for cost/performance 3-Jan-06ANL Director's Colloquium60 Beam Detector Interface Tauchi LCWS05 3-Jan-06ANL Director's Colloquium61 Our task is to continue studies on physics at the linear collider more precisely and more profoundly, taking into account progresses in our field, as well as on developments of detector technologies best suited for the linear collider experiment. As we know from past experiences, this will be enormously important to realize the linear collider. Akiya Miyamoto ACFA Joint Linear Collider Physics and Detector Working Group 3-Jan-06ANL Director's Colloquium62 Accelerator Physics Challenges Develop High Gradient Superconducting RF systems Requires efficient RF systems, capable of accelerating high power beams (~MW) with small beam spots(~nm). Achieving nm scale beam spots Requires generating high intensity beams of electrons and positrons Damping the beams to ultra-low emittance in damping rings Transporting the beams to the collision point without significant emittance growth or uncontrolled beam jitter Cleanly dumping the used beams. Reaching Luminosity Requirements Designs satisfy the luminosity goals in simulations A number of challenging problems in accelerator physics and technology must be solved, however. 3-Jan-06ANL Director's Colloquium63 Test Facility at KEK 3-Jan-06ANL Director's Colloquium64 Test Facility at SLAC 3-Jan-06ANL Director's Colloquium65 TESLA Test Facility Linac - DESY laser driven electron gun photon beam diagnostics undulator bunch compressor superconducting accelerator modules pre- accelerator e - beam diagnostics 240 MeV120 MeV16 MeV4 MeV 3-Jan-06ANL Director's Colloquium66 Fermilab ILC SCRF Program International Linear Collider Timeline Global Design EffortProject Baseline configuration Reference Design ILC R&D Program Technical Design Expression of Interest to Host International Mgmt 3-Jan-06ANL Director's Colloquium68 Conclusions We have determined a number of very fundamental physics questions to answer, like . What determines mass? What is the dark matter? Are there new symmetries in nature? What explains the baryon asymmetry? Are the forces of nature unified We are developing the tools to answer these questions and discover new ones Neutrino Physics Large Hadron Collider International Linear Collider The next era of particle physics will be very exciting