plan ahead for the gde barry barish ilc consultations ura, washington dc 12-may-05

Plan ahead for the GDE

Barry BarishILC Consultations

URA, Washington DC12-May-05

12-May-05 ILC Consultations - Washington DC 2

main linacbunchcompressor

dampingring

source

pre-accelerator

collimation

final focus

IP

extraction& dump

KeV

few GeV

few GeVfew GeV

250-500 GeV

Starting Point for the GDE

Superconducting RF Main Linac


“Target” 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


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.


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 µs 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.


Reference Points for the ILC Design

33km47 km

TESLA TDR500 GeV (800 GeV)

US Options Study500 GeV (1 TeV)


TESLA Test Facility Linac

laser driven electron gun

photon beam diagnostics

undulatorbunch

compressor

superconducting accelerator modules

pre-accelerator

e- beam diagnostics

e- beam diagnostics

240 MeV 120 MeV 16 MeV 4 MeV


Experimental Test Facility - KEK

• Prototype Damping Ring for X-band Linear Collider

• Development of Beam Instrumentation and Control


Evaluation: Technical Issues


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



• 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)



• 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



• 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.



– 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)


International/Regional Organization

ILC-Americas Regional Team Regional Director and Deputy Institutional ILC Managers for major instiutional members

CornellILC-NSF PI

TRIUMFILC-CanadaManager

NSF-funded Institutions

Canadian Institutions

Lead Labs

Work Package

Oversight ILCSC

GDE - Director

RegionalUSLCSG

FundingAgencies

FNALILC-FNALManager

WP 1.FNAL

WP 1.ANL

WP 3.FNAL

SLACILC-SLACManager

WP 2.SLAC

WP 2.BNL

WP 3.SLAC

communications

ILC-Asia ILC-Europe

International

Regional


ILC Design Issues

First Consideration : Physics Reach

ILC Parameters

Energy Reach

2cm fill linac RFE b L G

Luminosity RF AC BS

cm y

PL

E


Working Parameter Set“Point Design”

Center of Mass Energy 500 1000 GeV

Design Luminosity 2 3 1034cm-2sec-1

Linac rf frequency GHzAccelerating gradient MV/mPulse repetition rate HzBunches/pulseBunch separation nsec

Particles/bunch x1010

Bunch train length msecBeam power 11 23 MW/beam

sx/sy at IP 655/7 554/4 nm

Site AC power 180 356 MW

5

1.3

2866

2820307

30


GDE will do a “Parametric” Design

nom low N lrg Y low P

N 1010 2 1 2 2

nb 2820 5640 2820 1330

ex,y mm, nm 9.6, 40 10,30 12,80 10,35

bx,y cm, mm 2, 0.4 1.2, 0.2 1, 0.4 1, 0.2

sx,y nm 543, 5.7 495, 3.5 495, 8 452, 3.8

Dy 18.5 10 28.6 27

dBS % 2.2 1.8 2.4 5.7

sz mm 300 150 500 200

Pbeam MW 11 11 11 5.3

L 1034 2 2 2 2

Range of parametersdesign to achieve 21034


Towards the ILC Baseline Design


e- Beam Transport XFEL

e- Damping Ring

HEP & XFEL Experiments

e- Main LINAC e+ Beam delivery e+ Main LINAC

e+ Damping Ringe- Sources e+ Beam Transport

e- Beam delivery

e+ Source

e- Switchyard XFEL

PreLinac

PreLinac

Beam DumpsDESY site Westerhorn

TESLA machine schematic view

Power Water & Cryogenic Plants

Machine cost distribution

Main LINAC Modules

Main LINAC RF System

Civil Engineering

MachineInfrastructure

X FELIncrementals

Damping Rings

HEP Beam Delivery

AuxiliarySystems

Injection System

1131

~ 33 km

587 546

336241 215

124 101 97

Million Euro

TESLA Cost Estimate3,136 M€ (no contingency, year 2000) + ~7000 person years


Cost Breakdown by Subsystem

cf31%

structures18%rf

12%

systems_eng8%

installation&test7%

magnets6%

vacuum4%

controls4%

cryo4%

operations4%

instrumentation2%

Civil

SCRF Linac


RF SC Linac ChallengesEnergy: 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 MV/m, (operating at 30 MV/m)

• Trade-off cost and technical risk.

1 mRisk

Cos

t

~T

heor

etic

al M

ax


(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


Gradient

Results from KEK-DESY collaboration

must reduce spread (need more statistics)

single

-cell

measu

rem

ents

(in

nin

e-c

ell

cavit

ies)


New Cavity Shape for Higher Gradient?

TESLA Cavity

• A new cavity shape with a small Hp/Eacc ratio around35Oe/(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)

Alternate Shapes


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 G2/Q0

– cost of cryoplants goes up!


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.


Klystron Development

THALUS

CPITOSHIBA

10MW 1.4ms Multibeam Klystrons~650 for 500 GeV+650 for 1 TeV upgrade


Towards the ILC Baseline Design

Not cost drivers

But can be L performancebottlenecks

Many challenges!


Parameters of Positron Sources

rep rate# of bunches per pulse

# of positrons per bunch

# of positrons per pulse

TESLA TDR 5 Hz 2820 2 · 1010 5.6 · 1013

NLC 120 Hz 192 0.75 · 1010 1.4 · 1012

SLC 120 Hz 1 5 · 1010 5 · 1010

DESY positron source

50 Hz 1 1.5 · 109 1.5 · 109


Positron Source

• Large amount of charge to produce

• Three concepts:– undulator-based (TESLA TDR baseline)

– ‘conventional’ – laser Compton based


Strawman Final Focus



• Organize the ILC effort globally– Undertake making a “global design” over the next few years

for a machine that can be jointly implemented internationally. • Snowmass Aug 05 --- Begin to define Configuration (1st Step)

• GDE Dec 05 --- Baseline Configuration document by end of 2005

• Put Baseline under Configuration Control

• Conceptual Design of Baseline by end of 2006– Include site dependence – 3 or more sample sites– Detector Design Concept / Scope (1 vs 2, options, etc)– Reliable Costs -- emphasis during design on cost consciousness ---

value Engineering, trade studies, industrialization, etc

– 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)


Some issues regarding the GDE?

– Make a truly International GDE– Create a common fund– Interact with all our communities– Interact / work with FALC?– Make steps toward central authority, rather than

regional authority for GDE or successor.– Develop plan toward an international laboratory

– Make a realistic and affordable design ready for construction by the time of LHC results

plan ahead for the gde barry barish ilc consultations ura, washington dc 12-may-05

Documents

ilc design

ilc effort

control slide

tev slide

gde design staff

gde administrative

term plan staff

mev120 mev16 mev4 mev