Barish FNAL Users Mtg 05

Slide1: 

News from the ILC Barry Barish Users’ Meeting Fermilab 9-June-05

Why e+e- Collisions?: 

Why e+e- Collisions? elementary particles well-defined energy, angular momentum uses full COM energy produces particles democratically can mostly fully reconstruct events

Slide3: 

A Rich History as a Powerful Probe

Slide4: 

The Energy Frontier

Why a TeV Scale?: 

Why a TeV Scale? Two parallel developments over the past few years (the science) The precision information e+e- and n data at present energies 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 needing both pp and e+e- collisions to fully exploit the exciting science expected in the 1 TeV energy scale.

Why a TeV Scale e+e- Accelerator?: 

Why a TeV Scale e+e- Accelerator? Two parallel developments over the past few years (the technology) Designs and technology demonstrations have matured on two technical approaches for an e+e- collider that are well matched to our present understanding of the physics.

Which Technology to Choose?: 

Which Technology to Choose? 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 required uniting behind one technology, and then working toward a unified global design based on the recommended technology.

Slide8: 

International Technology Review Panel

Evaluate a Criteria Matrix: 

Evaluate a Criteria Matrix The panel analyzed the technology choice through studying a matrix having six general categories with specific items under each: the scope and parameters specified by the ILCSC; technical issues; cost issues; schedule issues; physics operation issues; and more general considerations that reflect the impact of the LC on science, technology and society

The Recommendation: 

The 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). The superconducting technology has several very nice features for application to a linear collider. They follow in part from the low rf frequency.

Slide11: 

The Community then Self-Organized Nov 13-15, 2004

Slide12: 

The First ILC Meeting at KEK

Slide13: 

The Global Design Effort Formal organization begun at LCWS 05 at Stanford in March 2005 when I became director of the GDE Technically Driven Schedule

GDE – Near Term Plan: 

GDE – Near Term Plan Staff the GDE Administrative, Communications, Web staff Regional Directors (each region) Engineering/Costing Engineer (each region) Civil Engineer (each region) Key Experts for the GDE design staff from the world community (please give input) Fill in missing skills (later) Total staff size about 20 FTE (2005-2006)

GDE – Near Term Plan: 

GDE – Near Term Plan Schedule Begin to define Configuration (Aug 05) Baseline Configuration Document by end of 2005 ----------------------------------------------------------------------- Put Baseline under Configuration Control (Jan 06) Develop Reference Design Report by end of 2006 Three volumes -- 1) Reference Design Report; 2) Shorter glossy version for non-experts and policy makers ; 3) Detector Concept Report

GDE – Near Term Plan: 

GDE – Near Term Plan Organize the ILC effort globally First Step --- Appoint Regional Directors within the GDE who will serve as single points of contact for each region to coordinate the program in that region. (Gerry Dugan (North America), Fumihiko Takasaki (Asia), offered to Brian Foster (Europe)) Make Website, coordinate meetings, coordinate R&D programs, etc R&D Program Coordinate worldwide R & D efforts, in order to demonstrate and improve the performance, reduce the costs, attain the required reliability, etc. (Proposal Driven to GDE)

Slide17: 

Starting Point for the GDE Superconducting RF Main Linac

Parameters for the ILC: 

Parameters for the ILC Ecm 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

Towards the ILC Baseline Design: 

Towards the ILC Baseline Design

Slide20: 

rf bands: L-band (TESLA) 1.3 GHz l = 3.7 cm S-band (SLAC linac) 2.856 GHz 1.7 cm C-band (JLC-C) 5.7 GHz 0.95 cm X-band (NLC/GLC) 11.4 GHz 0.42 cm (CLIC) 25-30 GHz 0.2 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

Cost Breakdown by Subsystem: 

Cost Breakdown by Subsystem Civil SCRF Linac

TESLA Cavity: 

TESLA Cavity 9-cell 1.3GHz Niobium Cavity Reference design: has not been modified in 10 years ~1m

What Gradient to Choose?: 

What Gradient to Choose?

Gradient: 

Gradient Results from KEK-DESY collaboration must reduce spread (need more statistics) single-cell measurements (in nine-cell cavities)

Slide25: 

(Improve surface quality -- pioneering work done at KEK) BCP EP 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

How Costs Scale with Gradient?: 

How Costs Scale with Gradient? Relative Cost Gradient MV/m 35MV/m is close to optimum Japanese are still pushing for 40-45MV/m 30 MV/m would give safety margin C. Adolphsen (SLAC)

Fermilab - Emerging ILC SCRF Program: 

Fermilab - Emerging ILC SCRF Program H Carter

Fermilab ILC SCRF Program: 

Fermilab ILC SCRF Program

Fermilab ILC SCRF Program: 

Fermilab ILC SCRF Program

Fermilab ILC SCRF Program: 

Fermilab ILC SCRF Program

Fermilab ILC SCRF Program: 

Fermilab ILC SCRF Program

Fermilab ILC SCRF Program: 

Fermilab ILC SCRF Program

TESLA Cavity: 

TESLA Cavity 9-cell 1.3GHz Niobium Cavity Reference design: has not been modified in 10 years ~1m

Evolve the Cavities Minor Enhancement: 

Evolve the Cavities Minor Enhancement Low Loss Design Modification to cavity shape reduces peak B field. (A small Hp/Eacc ratio around 35Oe/(MV/m) must be designed). This generally means a smaller bore radius Trade-offs (Electropolishing, weak cell-to-cell coupling, etc) KEK currently producing prototypes

New Cavity Design: 

New Cavity Design More radical concepts potentially offer greater benefits. But require time and major new infrastructure to develop. 28 cell Super-structure Re-entrant single-cell achieved 45.7 MV/m Q0 ~1010 (Cornell)

ILC Siting and Civil Construction: 

ILC Siting and Civil Construction 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

Fermilab ILC Civil Program: 

Fermilab ILC Civil Program A Fermilab Civil Group is collaborating with SLAC Engineers and soon with Japanese and European engineers 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

Strawman Final Focus: 

Strawman Final Focus

Fermilab and the ILC: 

Fermilab and the ILC Fermilab is rapidly developing a superconducting RF capability for the main linac design and development for the ILC. The Civil group at Fermilab is playing a central role in developing methods for understanding the siting and the interplay with the design. Plans are being developed to build a strong accelerator physics group at Fermilab for the ILC. There are many opportunities for involvement by the experimental community in the accelerator, the machine detector interfaces and the detector designs. -------------------------------------------------------------------------------------- Fermilab can position itself very well to be able to succesfully bid to host the ILC, without mortgaging the rest of the program

Slide41: 

Remarkable progress in the past two years toward realizing an international linear collider: important R&D on accelerator systems definition of parameters for physics choice of technology start the global design effort funding agencies are engaged Many major hurdles remain before the ILC becomes a reality (funding, site, international organization, detailed design, …), but there is increasing momentum toward the ultimate goal --- An International Linear Collider. Conclusions