On the Way to ILC Shekhar Mishra Fermilab Talk presented on behalf of ILC-GDE 2/16/06 Talk Presented at the 2006 Aspen Winter Conference: "Particle Physics at the Verge of Discovery"

International Linear Collider: Performance Specification (White Paper) –Initial maximum energy of 500 GeV, operable over the range GeV for physics running. –Equivalent (scaled by 500 GeV/  s) integrated luminosity for the first four years after commissioning of 500 fb -1. –Ability to perform energy scans with minimal changeover times. –Beam energy stability and precision of 0.1%. –Capability of 80% electron beam polarization over the range GeV. –Two interaction regions, at least one of which allows for a crossing angle enabling  collisions. –Ability to operate at 90 GeV for calibration running. –Machine upgradeable to approximately 1 TeV.

Road to: Reference Design Report 1 st ILC Workshop at KEK (11/2004) –working groups (WG) formed to begin identifying contentious design issues 2 nd ILC Workshop Snowmass (8/2005) –modified WG continue identifying baseline design and alternatives –newly formed ‘Global Groups’ begin to discuss and catalogue global design issues –2 nd Snowmass week: concentrate on the list of ‘Top 40’ critical design questions 1 st Meeting of the ILC-GDE (12/2005) –Acceptance of the Baseline Configuration Document (BCD) –Start work towards the Reference Design Report (12/2006, with Cost) –Formation of Accelerator System, Technology and Global systems –Formation of Design and Cost Board, Change Control Board and R&D Board ITRP Recommendation (Aug 2004) : Superconducting RF is accelerating technology for ILC

ICFA FALC Resource Board ILCSC GDE Directorate GDE Executive Committee Global R&D Program RDR Design Matrix GDE R & D Board GDE Change Control Board GDE Design Cost Board GDE RDR / R&D Organization GDE

ICFA FALC Resource Board ILCSC GDE Directorate GDE Executive Committee Global R&D Program RDR Design Matrix GDE R & D Board GDE Change Control Board GDE Design Cost Board GDE RDR / R&D Organization ILC Design Effort ILC R&D Program

Mission of Global Design Effort Produce a design for the ILC that includes –A detailed design concept –Performance assessments –Reliable international costing –An industrialization plan –Siting analysis –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 Baseline Machine (500GeV) not to scale ~30 km e+ 150 GeV (~1.2km) x2 R = 955m E = 5 GeV RTML ~1.6km ML ~10km (G = 31.5MV/m) 20mr 2mr BDS 5km

Luminosity Table minnommax Bunch charge N1 22x10^10 Number of bunchesn b Linac bunch intervalt b ns Bunch length  z  m Vertical emittance  y mm.mrad IP beta (500GeV)  x mm  y mm IP beta (1TeV)  x mm  y mm

Baseline Electron Source Positron-style room- temperature accelerating section diagnostics section standard ILC SCRF modules sub-harmonic bunchers + solenoids laser E= MeV DC Guns incorporating photocathode illuminated by a Ti: Sapphire drive laser. Long electron microbunches (~2 ns) are bunched in a bunching section Accelerated in a room temperature linac to about 100 MeV and SRF linac to 5 GeV.

Baseline Positron Source Helical Undulator Based Positron Source with Keep Alive System –The undulator source will be placed at the 150 GeV point in main electron linac. This will allow constant charge operation across the foreseen centre-of-mass energy operating range. 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

ILC Damping Ring: Baseline Design Positrons: Two rings of ~ 6 km circumference in a single tunnel. Two rings are needed to reduce e-cloud effects unless significant progress can be made with mitigation techniques. Preferred to 17 km due to: –Space-charge effects –Acceptance –Tunnel layout (commissioning time, stray fields) Electrons: one 6 km ring. Preferred to 3 km due to: –Larger gaps between mini-trains for clearing ions. –Injection and extraction kickers ‘low risk’

Main Linac: Baseline RF Unit

SRF Cavity Gradient Cavity type Qualified gradient Operational gradient Length*energy MV/m KmGeV initialTESLA upgradeLL * assuming 75% fill factor Total length of one 500 GeV linac  20km

Baseline ILC Cryomodule The baseline ILC Cryomodule will have 8 9-Cell cavities per cryomodule. The quadrupole will be at the center in the baseline design. Every 4 th cryomodule in the linac would include a quadrupole with a corrector and BPM package.

Modulator Baseline Alternate The Bouncer Compensated Pulse Transformer Style Modulator Operation: an array of capacitors is charged in parallel, discharged in series. (~2m) Will test full prototype in 2006

RF Power: Baseline Klystrons ThalesCPIToshiba Specification: 10MW MBK 1.5ms pulse 65% efficiency ILC DESY) has a very limited experience with these Klystrons. Production and operation of these Klystron are issues that needs to be addressed.

Beam Delivery System: Baseline & Alternatives Baseline (supported, at the moment, by GDE exec) –two BDSs, 20/2mrad, 2 detectors, 2 longitudinally separated IR halls Alternative 1 –two BDSs, 20/2mrad, 2 detectors in single IR Z=0 Alternative 2 –single IR/BDS, collider hall long enough for two push-pull detectors

From Baseline to a RDR Jan JulyDec 2006 Freeze Configuration Organize for RDR Bangalore Review Design/Cost Methodology Review Initial Design / Cost Review Final Design / Cost RDR Document Design and CostingRelease RDR FrascatiVancouverValencia

ILC R&D Major laboratories around the world are working on the ILC Accelerator R&D. –Europe DESY (TESLA) (55 Institutions) European XFEL CARE (11 Institutions) EuroTeV (27 Institutions) UK-LCABD (15 Institutions) –Americas (9 Laboratories and Universities) Fermilab SLAC –Asia (6 Institution in 5 countries) KEK Some Highlights of R&D Activities

Key Issues: ILC Main Linac Accelerator Technology The feasibility demonstration for the ILC requires that a cryomodule be assembled and tested at the design gradient of 35 MV/m. –Cavity technology development to routinely achieve > 35 MV/m and Q ~0.5- 1e10, Finalize the design of an RF Unit and evaluate the reliability issues. It is important to fully test the basic building block of the Linac. High Power Coupler, HOM, Tuner etc. 10 MWatt Multi-Beam Klystron, Fabrication, Operation and reliability RF Distribution, Controls and LLRF Instrumentation and Feedback Quadrupole, Corrector and Instrumentation package Cryogenic Distribution

Europe: ILC R&D DESY is leading the ILC R&D in Europe. The XFEL at DESY uses ILC Technology and have common R&D goals. –Cavity Gradient –Industrial studies and development of Main Linac Components. Coupler RF Power Cryogenics (LHC) Instrumentation Beam Delivery System

DESY: ILC Accelerator Modules in Operation At present DESY is operating modules 2*ACC1Febr 04 1*ACC2 June 02 3*ACC3April 03 4 ACC4April 03 5ACC5April 03 In single cavity measurements 6 out of 8 cavities reach 30 MV/m! ACC5 Laser Bunch Compressor bypass Undulators Collimator Bunch Compressor RF gun 5 MeV127 MeV370 MeV445 MeV Accelerating StructuresDiagnostics FEL diagnostics 250 m

ILC R&D at Fermilab ILC R&D effort at Fermilab is focused on key design & technical issues in support of the RDR, cost estimate and eventually the CDR for the ILC. We also have the goal of positioning the Americas to host the ILC at Fermilab Our efforts are focused on two main areas of the ILC –Main Linac Design –Civil and Site Development Main Linac R&D: –The goals are to demonstrate the feasibility of all Main Linac technical components, develop engineering designs, estimate costs, explore cost reduction, and engage US industry Civil and Site Development –Fermilab is working with the GDE and international partners to develop a matrix for comparing possible ILC sites –We also work to develop U.S. sites on or near Fermilab

ILC 1.3 GHz FNAL Industrial fabrication of cavities. BCP and vertical testing at Cornell (25 MV/m) EP and vertical testing at TJNL. ( 35 MV/m) Joint BCP/EP facility being developed ANL (late 06) High Power Horizontal test FNAL (ILCTA-MDB) Vertical test facility under FNAL ( IB1) Single/large Crystal cavity development with TJNL 4 cavities received from ACCEL 4 cavities on order at AES 4 cavities expected from KEK Bead pull RF FNAL Joint ANL/FNAL BCP/EP Facility

Jlab: Large Grain/Single Crystal Niobium Nb Discs LL cavity 2.3GHz E peak /E acc = H peak /E acc = 3.56 mT/MV/m

SLAC: Accelerator Design (RDR) Strong efforts throughout the design effort –Electron and positron sources –Contributions to the damping rings and RMTL –Main linac design and instrumentation –Rf sources –Beam Delivery System –Civil construction and conventional facilities Able to provide leadership for some RDR Area Sub-systems

SLAC: ILC R&D Program Broad R&D Program (cont.) –Linac rf sources Marx generator modulator –Electron and Positron sources NC structure, E-166, electron laser, and cathode –Damping rings SEY studies in PEP-II SEY Test Chamber for PEP-II Positron capture structures 12 KV Marx Cell

KEK: ILC Activities Highlights

KEK ATF Facility for DR and FF

KEK: Main Linac RF Unit R&D Goal: Achieve Higher Gradient >40 MV/m in a new Cavity Design

Summary After the technology selection the ILC Collaboration has made considerable progress towards the design of the ILC. The Baseline and Alternate design for each major Accelerator subsystems were defined at Snowmass The ILC-GDE has a approved the Baseline Configuration Document. The ILC-GDE is developing the ILC Reference Design Report, with cost estimate. It is expected to be done by the end of CY06 The ILC R&D around the world is moving fast with focus on key Accelerator Issues.