The ILC Project - uni-heidelberg.de · The ILC Project Based on ILC Reference Design Report (RDR) and Reports of European GDE Director (Brian Foster) to ECFA and EPS Karlheinz Meier,

Karlheinz Meier. Heidelberg, 31st Johns Hopkins Workshop

The ILC ProjectBased on ILC Reference Design Report (RDR) and Reports ofEuropean GDE Director (Brian Foster) to ECFA and EPS

Karlheinz Meier, U Heidelberg, JHWS 2007


History

Baseline Parameters of the ILC

Challenges

Worldwide Organisation

Selected ILC components presented here

Overall Layout

Cavities / Acceleration gradient

Positron Source

Beam Delivery / Experimental Areas

Cost

Next Steps

Outline


A Possible Apparatus for Electron-ClashingExperiments (*).

M. TignerLaboratory of Nuclear Studies. Cornell University - Ithaca,

N.Y.

Nuovo Cimento 37, 1228-1231 (1965)

Costs (Storage Ring) = ainfrastructure · R + bRF · E4/RCosts (Linear Collider) = cinfrastructure + RF · L

a,b well known : no increase beyond 200 GeV in storage ringsThe BIG question : what is c ?

History


High RF-PowerHigh RF-Transfer Efficiency

Low Emittance :

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E-smearing

LC Luminosity - where to put the Effort


The SLAC SLC Project

L = 1030 cm-2 s-1

Ecms = 100 GeV

σy = 600 nm


Electron Side Positron Side

Electron Damping Positron Damping

Positron Production

Beam Delivery

FEL

The DESY TESLA Project

L = 3·1034 cm-2 s-1 Ecms = 500 GeV σy = 5 nm

Key Technology taken from TESLA TDR to ILC :SC Cavities at 1.3 GHz (L-Band)


XFEL 20 GeVAccelerator underconstruction atDESY

928 TESLA / ILCtype SC RF-cavities

„Calibration project“for the ILC

The XFEL at DESY


• Ecms adjustable from 200 – 500 GeV

• Luminosity ∫Ldt = 500 fb-1 in 4 years

(corresponds to 2*1034 cm-2 s-1 )

• 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

ILC Reference Physics Parameters


Organisation : Global Design Effort - Set up by ILCSC via ICFA


ILC Timeline (GDE, Barry Barish, FNAL, June 2007)

now


ILC overall stage 1 layout in RDR (Reference Design Report) 2007

Main cost saving features :

„Central Campus“ with Experiments, Sources and Damping Rings (requires 14km long 5GeV beam transport systems over full length)

Single Beam Delivery System (Push-Pull for 2 Detectors)

11.3 km

6 km (150 GeV)

C = 6.7 km


2 Tunnel scheme for mainlinac (4.5 m diameter)

ILC cryomodule design

Main Linac Structure


Basic ILC Technical RDR Parameters

MW~230Total AC Power Consumptionkm31Total Site Lengthms0.95Beam pulse lengthMV/m31.5Average accelerating gradientHz5Repetition ratemA9.0Beam Currentcm-2s-1~2x1034Peak LuminosityGeV500Max. Center-of-mass energy


Main Linac RF Unit Overview

• Multibeam L-band klystron (10 MW)• 3 Cryostats (9+8+9 = 26 cavities)• 1 Quadrupole at the center• 278 positron units, 282 electron units (14560 cavities)• Nb cavities operating at 2K


Cavities• Baseline: TESLA-type 1.3 GHz

– Identical to XFEL cavities• Only beamtubes shortened

• Accelerating gradient– Average gradient in cryomodule

• 31.5 MV/m, Q>1x1010

• With the presently available technology– Average gradient lower than 31.5 MV/m– Spread of gradient large – If uniform distribution in 22<G<34 MV/m, average 28 MV/m: Cost increase ~7 %

ILC 9-Cell Cavity undervertical test at Cornell


RF Cavity R+D Programme

Establish 36 MV/m in low power tests

Single Cells : Optimise surface preparationProduction like process of full size cavities

Establish high yield before EDR

Establish 31.5 MV/m in accelerator modules

200 µm 200 µm

Buffered chemical polishing Electro-Polishing


• Undulator scheme - Baseline (Alternatives : e on target, Compton)

– Input Electron beam at 150 GeV, 6 km upstream

– Undulator• Helical, superconducting• length 147 m (longer for polarized e+)

Positron Source


BDS (Beam Delivery System)

From main linac exit to the IP (Interaction Point)and to the beam dump

Roles of BDS• Focus the beam to the desired spot size for

collision• Remove beam-halo to minimize the background

events• Protect the beamline and detectors against mis-

steered beam• Diagnostics of the linac beam (Spectrometry)• Safely dump the spent beams


Interaction Region - Experiments

• Single IR, 14 mrad crossing angle, 2 Push-Pull detectors

• Large cost savings compared to 2 IR solution :– ~200 M$ compared with 2 IR with crossing angles 14 + 14

mrad (even more if one IR has “small angle” crossing)

• Push-pull detectors– Task force from WWS (World Wide Study) and GDE formed– Conclusion so far

• No show-stoppers• But need careful design and R&D works

Not excluded, but not baseline :

2 IR with (fast or slow) beam switch (luminosity sharing)

1 IR with 1 stationary detector


detectorA

detectorB

may beaccessibleduring run

detectorB

detectorA

IR Hall for push-pull (evolving concept)

detectorA

detectorB

Platform for electronic andservices (~10*8*8m). Shielded(~0.5m of concrete) from fivesides. Moves with detector.

accessibleduring run


Beam Delivery System Layout

2.2 km vs 2 m

view

1 km vs 2 m

view


Crab Crossing

• Large crossing angle14mrad

• Need to deflect headand tail oppositely

• Special Crab cavity– 3.9 GHz SC– phase tolerance ~60 fs– prototype fabricated


ILC CostsThe reference design was“frozen” on for RDR production,including costs.

This is a snapshot. The design willcontinue to evolve, due to R&D,accelerator studies & valueengineering.

The value costs havealready been reviewedmany times.

Σ Value = 6.62 B ILC Units

SummaryRDR “Value” Costs

Total Value Cost (FY07)4.80 B ILC Units Shared

+1.82 B Units Site Specific

+14.1 K person-years

(“explicit” labor = 24.0 M person-hrs@ 1,700 hrs/yr)

1 ILC Unit = $ 1 (2007)


BCD Construction Startup

2006 2010 2014 2018

RDR EDR BeginConst

EndConst

EngineerDesign

All regions ~ 5 yrs

Siting Plan being Developed

SitePrep

SiteSelect

R & D -- Industrialization

DetectorInstall

DetectorConstruct

Future - A Technically Driven Timeline


Summary and Outlook

• Rather detailed Reference-Design für the ILC available

• Reliable Costing based on RDR has been carried out

• Strong R+D Programme in the US, Asia and Europe

• Engineering Design Phase to start now

• Supported by EU in Europe

• Large scale industralized production of > 10.000 31.5 MV/m Cavities is amajor challenge

• Technically driven time planning available with ILC operation startingbefore 2020

• Experiements being planned (call for LoIs likely to happen this year ornext year)

http://www.linearcollider.org

Documents

The ILC Project - uni-heidelberg.de · The ILC Project Based on ILC Reference Design Report (RDR) and Reports of European GDE Director (Brian Foster) to ECFA and EPS Karlheinz Meier,