International Linear Colllider International Linear Colllider Global Design Effort Global Design Effort Barry Barish ILCSC - Frankfurt 10-May-05
Starting Point for the GDE pre-accelerator few GeV source KeV damping extraction ring & dump few GeV 250-500 GeV final focus few GeV IP bunch main linac compressor collimation Superconducting RF Main Linac Superconducting RF Main Linac 10-May-05 ILCSC 2
“Target” 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 10-May-05 ILCSC 3
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. 10-May-05 ILCSC 4
TESLA Cavity • RF accelerator structures consist of close to 21,000 9-cell niobium cavities operating at gradients of 23.8 MV/m (unloaded as well as beam loaded) for 500 GeV c.m. operation. • The rf pulse length is 1370 µ s and the repetition rate is 5 Hz. At a later stage, the machine energy may be upgraded to 800 GeV c.m. by raising the gradient to 35 MV/m. 10-May-05 ILCSC 5
Reference Points for the ILC Design TESLA TDR 500 GeV (800 GeV) 33km 47 km US Options Study 500 GeV (1 TeV) 10-May-05 ILCSC 6
TESLA Test Facility Linac e - beam e - beam diagnostics diagnostics bunch laser driven undulator compressor electron gun photon beam pre- superconducting accelerator diagnostics accelerator modules 240 MeV 120 MeV 16 MeV 4 MeV 10-May-05 ILCSC 7
Experimental Test Facility - KEK • Prototype Damping Ring for X-band Linear Collider • Development of Beam Instrumentation and Control 10-May-05 ILCSC 8
Evaluation: Technical Issues 10-May-05 ILCSC 9
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. – Make Website, coordinate meetings, collaborative R&D, etc Represent the ILC internationally • – Represent the ILC internationally – Outreach to our community and beyond 10-May-05 ILCSC 10
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) 10-May-05 ILCSC 11
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 Conceptual Design Report by end of 2006 Three volumes -- 1) Conceptual Design Report; • 2) Shorter glossy version for non-experts and policy makers ; 3) Detector Concept Report 10-May-05 ILCSC 12
GDE – Near Term Plan What is the Conceptual Design Report • – Include site dependence – 3 or more sample sites – Detector Design Concept / Scope (1 vs 2, options, etc) – Reliable Costs – strong emphasis during design on cost consciousness --- value Engineering, trade studies, industrialization, etc This report will be the basis for moving on to a • technical design to be ready before physics from the LHC establishes the science case. 10-May-05 ILCSC 13
GDE – Near Term Plan – 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) 10-May-05 ILCSC 14
International/Regional Organization ILCSC Oversight International GDE - Director ILC-Asia ILC-Europe ILC-Americas Regional Team USLCSG communications Regional Director and Deputy Regional Institutional ILC Managers Regional for major instiutional members Funding Agencies FNAL SLAC Cornell TRIUMF Lead ILC-FNAL ILC-SLAC ILC-NSF PI ILC-Canada Labs Manager Manager Manager WP 1.FNAL WP 2.SLAC NSF-funded Institutions Work WP 1.ANL WP 2.BNL Package Canadian WP 3.FNAL WP 3.SLAC Institutions 10-May-05 ILCSC 15
ILC Design Issues First Consideration : Physics Reach Energy Reach = E 2 b L G cm fill linac RF ILC Parameters η δ P Luminosity ∝ RF AC BS L γε E cm y 10-May-05 ILCSC 16
Working Parameter Set “Point Design” “Point Design” Center of Mass Energy 500 1000 GeV 10 34 cm -2 sec -1 Design Luminosity 2 3 Linac rf frequency 1.3 GHz Accelerating gradient 30 MV/m Pulse repetition rate 5 Hz Bunches/pulse 2820 Bunch separation 307 nsec x10 10 Particles/bunch 2 µ sec Bunch train length 866 Beam power 11 23 MW/beam σ x / σ y at IP 655/7 554/4 nm Site AC power 180 356 MW 10-May-05 ILCSC 17
GDE w ill do a “Parametric” Design nom low N lrg Y low P × 10 10 2 1 2 2 N 2820 5640 2820 1330 n b Range of e x,y mm, nm 9.6, 40 10,30 12,80 10,35 param eters design to b x,y cm, mm 2, 0.4 1.2, 0.2 1, 0.4 1, 0.2 achieve s x,y nm 543, 5.7 495, 3.5 495, 8 452, 3.8 2 × 1 0 3 4 18.5 10 28.6 27 D y % 2.2 1.8 2.4 5.7 d BS mm 300 150 500 200 s z MW 11 11 11 5.3 P beam × 10 34 2 2 2 2 L 10-May-05 ILCSC 18
Tow ards the ILC Baseline Design 10-May-05 ILCSC 19
TESLA Cost Estimate 3,136 M€ (no contingency, year 2000) + ~7000 person years ~ 33 km Power Water & Cryogenic Plants PreLinac e+ Source e- Damping Ring e+ Beam Transport e+ Damping Ring e- Sources e- Main LINAC e- Beam delivery e+ Beam delivery e+ Main LINAC PreLinac Beam Dumps Weste rhorn DESY site e- Beam Transport XFEL T ESLA m a c hine sc hem a tic view e- Switchyard XFEL 1131 Million Euro HEP & XFEL Experiments Machine cost distribution 587 546 336 241 215 124 101 97 Damping Auxiliary Injection Main LINAC Main LINAC Civil Machine X FEL HEP Beam Rings Systems System Modules RF System Engineering Infrastructure Incrementals Delivery 10-May-05 ILCSC 20
RF SC Linac Challenges Energy: 500 GeV, upgradeable to 1000 GeV • RF Accelerating Structures – Accelerating structures must support the desired gradient in an operational setting and there must be a cost effective means of fabrication. – ~17,000 accelerating cavities/500 GeV – Current performance goal is 35 ~Theoretical Max MV/m, (operating at 30 MV/m ) • Trade-off cost and technical risk. Cost 1 m Risk 10-May-05 ILCSC 21
Electro-polishing (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 10-May-05 ILCSC 22
Gradient single-cell measurements (in nine-cell cavities) Results from KEK-DESY collaboration must reduce spread (need more statistics) 10-May-05 ILCSC 23
New Cavity Shape for Higher Gradient? TESLA Cavity Alternate Shapes • A new cavity shape with a small Hp/Eacc ratio around 35Oe/(MV/m) must be designed. - Hp is a surface peak magnetic field and Eacc is the electric field gradient on the beam axis. - For such a low field ratio, the volume occupied by magnetic field in the cell must be increased and the magnetic density must be reduced. - This generally means a smaller bore radius. - There are trade-offs (eg. Electropolishing, weak cell-to-cell coupling, etc) 10-May-05 ILCSC 24
Gradient vs Length • Higher gradient gives shorter linac – cheaper tunnel / civil engineering – less cavities – (but still need same # klystrons) • Higher gradient needs more refrigeration – ‘cryo-power’ per unit length scales as G 2 / Q 0 – cost of cryoplants goes up! 10-May-05 ILCSC 25
Klystrons • RF power generation and delivery – The rf generation and distribution system must be capable of delivering the power required to sustain the design gradient: • 10 MW × 5 Hz × 1.5 msec • ~700 klystrons and modulators for 500 GeV – The rf distribution system is relatively simple, with each klystron powering 30-36 cavities. • Status – Klystrons under development by three vendors (in Europe, Japan, and U.S.) • Three units from European vendor (Thales) have come close to meeting spec. • Sheet beam under development at SLAC (cost reduction) – Modulators meeting performance spec have been built and operated (at TTF) for the last decade. 10-May-05 ILCSC 26
Klystron Development THALUS CPI TOSHIBA 10MW 1.4ms Multibeam Klystrons ~650 for 500 GeV +650 for 1 TeV upgrade 10-May-05 ILCSC 27
Tow ards the ILC Baseline Design Not cost drivers But can be L performance bottlenecks Many challenges! 10-May-05 ILCSC 28
Parameters of Positron Sources # of bunches # of positrons # of positrons rep rate per pulse per bunch per pulse 2 · 10 10 5.6 · 10 13 TESLA TDR 5 Hz 2820 NLC 120 Hz 192 0.75 · 10 10 1.4 · 10 12 SLC 120 Hz 1 5 · 10 10 5 · 10 10 DESY positron 50 Hz 1 1.5 · 10 9 1.5 · 10 9 source 10-May-05 ILCSC 29
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