1. The International Linear Collider Barry Barish 15-Nov-05

2. BNL Physics 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. 15-Nov-05BNL Physics 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

4. 15-Nov-05BNL Physics Colloquium4 Neutrinos observed from the sun ! Davis and Bahcall Koshiba 4 1 H  4He + 2e + + 2 v e + energy SuperKamiokande

5. 15-Nov-05BNL Physics Colloquium5 But, too few neutrinos … If neutrinos have mass, then as conjectured earlier by Bruno Pontecorvo, neutrinos could “oscillate” from one type to another. In this case, some of the original electron neutrinos made in the sun convert to other neutrinos on trajectory to the earth

6. 15-Nov-05BNL Physics Colloquium6 Puzzle resolved … neutrinos oscillate SNO (Canada) used D 2 0 to detect other neutrino types KamLAND used terrestrial neutrinos from reactors, observes oscillations

7. 15-Nov-05BNL Physics Colloquium7 Cold Dark Matter 20% Ordinary (baryonic) Matter 5% Hot Dark Matter (neutrinos) < 5% Neutrinos – Some of the Dark Matter! Dark Energy 70%

8. 15-Nov-05BNL Physics Colloquium8 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

9. 15-Nov-05BNL Physics Colloquium9 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?

10. 15-Nov-05BNL Physics Colloquium10 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 ~0.5-1.0 TeV ILC and the LHC science.

11. 15-Nov-05BNL Physics Colloquium11 Electroweak Precision Measurements What causes mass?? The mechanism – Higgs or alternative appears around the corner

12. 15-Nov-05BNL Physics Colloquium12 Accelerators and the Energy Frontier Large Hadron Collider CERN – Geneva Switzerland

13. 15-Nov-05BNL Physics Colloquium13 LHC and the Energy Frontier Source of Particle Mass The Higgs Field Discover the Higgs or variants or ??? fb -1 LEP FNAL

14. 15-Nov-05BNL Physics Colloquium14 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

15. 15-Nov-05BNL Physics Colloquium15 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

16. 15-Nov-05BNL Physics Colloquium16 But, not quite high enough energy …. Discovery Of Charm Particles and 3.1 GeV Burt Richter Nobel Prize SPEAR at SLAC

17. 15-Nov-05BNL Physics Colloquium17 The rich history for e + e - continued as higher energies were achieved … DESY PETRA Collider

18. 15-Nov-05BNL Physics Colloquium18 Electron Positron Colliders The Energy Frontier

19. 15-Nov-05BNL Physics Colloquium19 Why e + e - Collisions ? elementary particles well-defined –energy, –angular momentum uses full COM energy produces particles democratically can mostly fully reconstruct events

20. 15-Nov-05BNL Physics Colloquium20 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 !

21. 15-Nov-05BNL Physics Colloquium21 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

22. 15-Nov-05BNL Physics Colloquium22 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 ?

23. 15-Nov-05BNL Physics Colloquium23 BosonsFermions Virtues of Supersymmetry: –Unification of Forces –The Hierarchy Problem –Dark Matter … Is There a New Symmetry in Nature? Supersymmetry

24. 15-Nov-05BNL Physics Colloquium24 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

25. 15-Nov-05BNL Physics Colloquium25 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.

26. 15-Nov-05BNL Physics Colloquium26 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

27. 15-Nov-05BNL Physics Colloquium27 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.

28. 15-Nov-05BNL Physics Colloquium28 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

29. 15-Nov-05BNL Physics Colloquium29 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 ITRP’s recommendation on August 20, 2004

30. 15-Nov-05BNL Physics Colloquium30 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).

31. 15-Nov-05BNL Physics Colloquium31 The Community Self-Organized Nov 13-15, 2004

32. 15-Nov-05BNL Physics Colloquium32 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.)

33. 15-Nov-05BNL Physics Colloquium33 GDE Members Chris Adolphsen, SLAC Jean-Luc Baldy, CERN Philip Bambade, LAL, Orsay Barry Barish, Caltech Wilhelm Bialowons, DESY Grahame Blair, Royal Holloway Jim Brau, University of Oregon Karsten Buesser, DESY Elizabeth Clements, Fermilab Michael Danilov, ITEP Jean-Pierre Delahaye, CERN, Gerald Dugan, Cornell University Atsushi Enomoto, KEK Brian Foster, Oxford University Warren Funk, JLAB Jie Gao, IHEP Terry Garvey, LAL-IN2P3 Hitoshi Hayano, KEK Tom Himel, SLAC Bob Kephart, Fermilab Eun San Kim, Pohang Acc Lab Hyoung Suk Kim, Kyungpook Nat’l Univ Shane Koscielniak, TRIUMF Vic Kuchler, Fermilab Lutz Lilje, DESY Tom Markiewicz, SLAC David Miller, Univ College of London Shekhar Mishra, Fermilab Youhei Morita, KEK Olivier Napoly, CEA-Saclay Hasan Padamsee, Cornell University Carlo Pagani, DESY Nan Phinney, SLAC Dieter Proch, DESY Pantaleo Raimondi, INFN Tor Raubenheimer, SLAC Francois Richard, LAL-IN2P3 Perrine Royole-Degieux, GDE/LAL Kenji Saito, KEK Daniel Schulte, CERN Tetsuo Shidara, KEK Sasha Skrinsky, Budker Institute Fumihiko Takasaki, KEK Laurent Jean Tavian, CERN Nobu Toge, KEK Nick Walker, DESY Andy Wolski, LBL Hitoshi Yamamoto, Tohoku Univ Kaoru Yokoya, KEK 49 members Americas 16 Europe 21 Asia 12

34. 15-Nov-05BNL Physics Colloquium34 Designing a Linear Collider Superconducting RF Main Linac

35. 15-Nov-05BNL Physics Colloquium35 rf bands: L-band (TESLA)1.3 GHz  = 3.7 cm S-band (SLAC linac) 2.856 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

36. 15-Nov-05BNL Physics Colloquium36 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 2006. –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 2006. I am proposing we use a “parametric” design and costing approach. –Technical performance and physics performance will be evaluated for the reference design

37. 15-Nov-05BNL Physics Colloquium37 Parametric Approach Parametric approach to design –machine parameters : a space to optimize the machine –Trial parameter space, being evaluated by subsystems –machine design : incorporate change without redesign; incorporates value engineering, trade studies at each step to minimize costs

38. 15-Nov-05BNL Physics Colloquium38 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

39. 15-Nov-05BNL Physics Colloquium39 The Key Decisions Critical choices: luminosity parameters & gradient

40. 15-Nov-05BNL Physics Colloquium40 Making Choices – The Tradeoffs Many decisions are interrelated and require input from several WG/GG groups

41. 15-Nov-05BNL Physics Colloquium41 Superconducting RF Cavities High Gradient Accelerator 35 MV/meter -- 40 km linear collider

42. 15-Nov-05BNL Physics Colloquium42 Improved Cavity Shapes

43. 15-Nov-05BNL Physics Colloquium43 Improved Fabrication

44. 15-Nov-05BNL Physics Colloquium44 Improved Processing Electropolishing Chemical Polish Electro Polish

45. 15-Nov-05BNL Physics Colloquium45 (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

46. 15-Nov-05BNL Physics Colloquium46 Gradient Results from KEK-DESY collaboration must reduce spread (need more statistics) single-cell measurements (in nine-cell cavities)

47. 15-Nov-05BNL Physics Colloquium47 Baseline Gradient

48. 15-Nov-05BNL Physics Colloquium48 Large Grain Single Crystal Nb Material

49. 15-Nov-05BNL Physics Colloquium49 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 earth’s 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

50. 15-Nov-05BNL Physics Colloquium50 1 vs 2 Tunnels Tunnel must contain –Linac Cryomodule –RF system –Damping Ring Lines Save maybe $0.5B Issues –Maintenance –Safety –Duty Cycle

51. 15-Nov-05BNL Physics Colloquium51 Possible Tunnel Configurations One tunnel of two, with variants ??

52. 15-Nov-05BNL Physics Colloquium52 ILC Civil Program Civil engineers from all three regions working to develop methods of analyzing the siting issues and comparing sites. The current effort is not intended to select a potential site, but rather to understand from the beginning how the features of sites will effect the design, performance and cost

53. 15-Nov-05BNL Physics Colloquium53 Beam Detector Interface Tauchi LCWS05

54. 15-Nov-05BNL Physics Colloquium54 “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

55. 15-Nov-05BNL Physics Colloquium55 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.

56. 15-Nov-05BNL Physics Colloquium56 Test Facility at KEK

57. 15-Nov-05BNL Physics Colloquium57 Test Facility at SLAC

58. 15-Nov-05BNL Physics Colloquium58 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

59. 15-Nov-05BNL Physics Colloquium59 Fermilab ILC SCRF Program

60. International Linear Collider Timeline 2005 2006 2007 2008 2009 2010 Global Design EffortProject Baseline configuration Reference Design ILC R&D Program Technical Design Expression of Interest to Host International Mgmt

61. 15-Nov-05BNL Physics Colloquium61 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