Marc Ross Nick Walker Akira Yamamoto 1 st PAC Meeting 19 th October, 2008 Machine Design & Cost Reduction Activities 1.

Marc Ross

Nick Walker

Akira Yamamoto

1st PAC Meeting19th October, 2008

Machine Design & Cost Reduction Activities

1

Content

• Brief (and superficial) introduction to RDR baseline.

• The RDR cost estimate

• Technical Design Phase cost-reduction strategy – the Minimum Machine

2

ILC Requirements

• Ecm adjustable from 200 – 500 GeV

• Luminosity: ∫Ldt = 500 fb-1 in 4 years – Peak at max. energy of 2×1034cm-2s-1

– Assume 1/ L scaling for <500 GeV

• Energy stability and precision below 0.1%• Electron polarization of at least 80%• The machine must be upgradeable to 1 TeV• Two detectors

– Single IR in push-pull configuration– Detector change-over in not more than 1

week

ILCSC Parameters group

ILCSC Parameters group

3

The ILC Reference Design

• 200-500 GeV centre-of-mass• Luminosity: 2×1034 cm-2s-1

• Based on accelerating gradient of 31.5 MV/m(1.3GHz SCRF)

~31 km

4

ILC Reference Design

5

• High-gradient R&D

• Industrialisation• Mass-production


Positronproduction

150 GeV primary e- beam used to generate gammas via a helical undulator.Thin-target conversion into e+e- pairs

1.2 km insert into main SCRF linac Additional “keep-

alive” independent thick-target source

(10% nominal)

6

ILC Reference Design• 6.4 km Damping Rings

– e+ / e-• Located centrally

– around Interaction Region (IR)– 10 m above IR plane

• Both rings housed in same tunnel (stacked)

Cockcroft institute, UK

7


• Beam Delivery System– Diagnostics– Beam halo collimation– Demagnification of the

beam at the Interaction Point

• Geometry laid out for Ecm ~ 1 TeV– Not all magnets

installed for 1 TeV

• ±2.2 km• Single interaction

region– Push/pull detector

concept assumed

SLAC

8

Cost (VALUE) Estimate

• Estimated cost (2007) ~6.7 Billion ILCU*– 4.87 BILCU shared– 1.78 BILCU site-specific

• 10,000 person-years “implicit” labour

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10

CFS identified as a major cost driver with high-potential for cost-saving

CFS requirements driven by machine design & layout


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Reduction of underground volume (tunnels, shafts, vaults) a primary target

75%

Stated TD Phase Goals (1/2)

• Definition of the basic parameters and layout of a “minimum machine configuration”, as a basis for understand cost-increments and cost-performance trade-offs (beginning 2009)

• Cost-reduction and performance studies (parametric studies) of the minimum machine, leading to possible options for the re-baseline. Evaluation of estimated cost and performance risk impact (end 2009).

• As part of the above, studies of a cost-optimised “shallow site” with a view to defining an optimum ‘reference site’ for further design studies (end 2009).

From the R&D Plan rel 2 (chapter 4)

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Stated TD Phase Goals (2/2)

• Evaluation of cost-reduction studies and status of critical R&D, leading to an agreed re-baseline of the reference machine (end of TD Phase 1, 2010)– Needs well-defined process; international community buy-off etc.

• Produce technical component specifications for technical systems; technical design of systems leading to cost estimates; value-engineering iteration (TD Phase 2)

• Generation and publication of TDR with updated technical design and VALUE estimate (end of TD Phase 2, 2012)

From the R&D Plan rel 2 (chapter 4)

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“Minimum Machine” Philosophy

• Direct performance – considered a physics ‘figure of merit’

• centre-of-mass energy or• peak luminosity.

– Understanding the derivatives of the direct cost of these physics performance parameters

• Indirect performance– into which we place margin, redundancy, etc.

– tend to impact operational aspects or– performance risk

• potentially affecting integrated luminosity within a given time frame

• Concentrate on Indirect– Do not change basic physics parameters

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Published Top-Level Schedule

today

15

Published Top-Level Schedule

today

Minimum machine studiesRe-baseline in 2010(publish in interim report)

Minimum machine studiesRe-baseline in 2010(publish in interim report)

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Minimum Machine: Current Definition

• “Minimum Machine” now refers to a set of identified options (elements) which may prove cost-effective

• Not a minimum in a definable sense– But a potential reduced-cost solutions…– with a potentially less margin (performance)

• An alternative design for study purposes– Comparison with RDR baseline– Cost (not performance) driven– options which were not studied during RDR phase

• Important to restrict options to manageable levels– available resources

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Identified Minimum Machine Elements

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Minimum Machine Elements

1. Single-tunnel solution(s)

2. Klystron Cluster concept

3. Central region integration

4. Low beam power option

5. Single-stage compressor

6. Quantify cost of TeV upgrade support

7. “Value engineering”19









Main Linac Specific

• Removal of support tunnel (single tunnel)– klystron cluster – XFEL-like– shallow site (JINR/Dubna)

• Klystron Cluster (HLRF)– 30 klystrons located in localised surface buildings– ~300 MW RF power distributed in beam tunnel via over-

moded waveguide– effectively ~1km RF unit

• Marx modulator– ongoing SLAC prototype

• Reduced cost solution for process-water cooling– Higher T specification (e.g. klystron cooling)

alternative options

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Main Linac Support Tunnel

• RDR (two-tunnel)– Access to equipment during

ops• Reliability/availability

• Shallow sites– Cut and cover like solutions– “service tunnel” on the

surface

• Single tunnel– European XFEL-like solution

• availability / reliability

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Klystron Cluster Concept

• RF power “piped” into accelerator tunnel

• Removal of service tunnel

• Access to klystrons maintained

• R&D needed to show power handling– Planned (SLAC,

KEK)

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SLAC









Central Region Integration

• Undulator-based positron source moved to end of linac(250 GeV point)

• e+ and e- sources share same tunnel as BDS– upstream BDS (optimised integration)– Including 5GeV injector linacs

• Removal of RDR “Keep Alive Source”– replace by few % ‘auxiliary’ source using main (photon) target– 500 MV warm linac, also in same tunnel

• Damping Rings– in BDS plane but horizontally displaced to avoid IR Hall– Injection/Ejection in same straight section – Circumference

• 6.4 km (current RDR baseline) • 3.2 km (possible low-P option)

alternative options

Initial “integration” studies show conceptually possible

(See draft document on PAC agenda web-site for details)

Initial “integration” studies show conceptually possible

(See draft document on PAC agenda web-site for details)

26









RDR Parameter Plane Revisited

• RDR machine design around so-called “Parameter Plane”

• 1 nominal + 3 ‘scaled’ parameter sets representing various possible ‘performance issues’• Low charge – failure to

make single bunch charge• Low power – failure to

make number of bunches

• Large y – failure to make emittance / vertical IP beam size

• As part of MM studies, review ‘parameter plane’ from a cost/performance issue

( )BSRF D y

y

L P H D

Main Linac $$$$

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Reduced Beam Power Option

• Reduce nb by factor of 2 (study scenario)

– Maintain luminosity by pushing on beam-beam• Similar to RDR Low-P parameter set, but• possible use of “travelling focus” concept

• “Minimum Cost” point of RDR parameter plane– Largest cost leverage of all sets in the table

• Spectrum of possible savings– ½ number of klystrons and modulators

– reduced circumference damping ring (6.4 3.2km)

– reduced associated CFS

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RDR Parameters Reviewed

Nom. RDR Low P RDR new Low P ECM (GeV) 500 500 500 Particles per bunch, N (×1010) 2.0 2.0 2.0Bunches per pulse, nb 2625 1320 1320 Pulse repetition rate (Hz) 5 5 5 Peak beam power, Pb (MW) 10.5 5.3 5.3 x (m) 10 10 10y (nm) 40 36 36x (cm) 2.0 1.1 1.1y (mm) 0.4 0.2 0.2Traveling focus No No Yes x (nm) 640 474 474y (nm) 5.7 3.8 3.8 z (m) 300 200 300 Beamstrahlung* E/E 0.023 0.045 0.036 Luminosity* (×1034 cm-2s-1) 2.0 1.7 1.9

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SLAC









Remaining MM Study Elements

• Single-stage compressor– Factor 20 bunch compression (z 300m @IP)– (RDR two-stage compressor with factor 45)

• Quantify cost of TeV upgrade support in RDR– Minimum length 500 GeV Ecm BDS– (High-power dumps?)

• Other “VALUE Engineering”– Water cooling– Vacuum solutions– Magnets & Power supplies– …

Encouraged activities

Considered parallel (on-going) to main ‘layout’ discussions

(not primary cost drivers)

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VERY

PRELIMIN

ARY!

to be confirm

ed• Main Linac (total) ~ 300 MILCU• Low-Power option ~ 400 MILCU• Central injector Integration ~ 100 MILCU• Single-stage compressor ~ 100 MILCU• Min. 500GeV BDS ~ 100 MILCU

– VERY preliminary: better estimates must be made• But still based/scaled from RDR value estimate

– Forms part of the justification for minimum machine studies– Elements not independent! Careful of potential double

counting!– Cost vs Performance vs Risk: important data for making

informed decisions in 2010

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Ball-Park Cost Increments

Types of Studies (2009)

• Interference / Integration– Lattice layouts – Tunnel cross-section models (CAD)– (Installation related)– Component placement etc

• Operations, Commissioning, Availability– Less independent machine operation– Reliability issues (accessibility)– Commissioning strategies etc.

• Hardware development, R&D– High-power RF distribution concept– Marx modulator (on-going)– Increased RF pulse length (low-P)

• Beam Dynamics– Emittance preservation– BDS tuning– Travelling focus ‘stability’– …

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Requires CAD (CFS) engineer(s), optics (accelerator physics) expert(s).Look for a (conceptual) engineering solution.

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Much more difficult to quantify.Looks for experienced expertsBrainstorm qualitative concepts (solutions)

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FTE and MS required.Well defined goals for R&D programme.Acceptance criteria of proposed solution.

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Beam dynamics and simulation specialists (lc experts).(good coordination, well defined questions)

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(RDR ACD concepts and R&D)

Towards a Re-Baselining in 2010

• Process– RDR baseline & VALUE element are maintained

• Formal baseline– MM elements needs to be studies/reviewed international

• Regional balance in the AP&D groups involved• Regular meetings and discussions• (but top-down control from PM)

– Formal review and re-baseline process beginning of 2010• Exact process needs definition (a PM action item for 2009)• Community sign-off mandatory

MM def MM studies

2009 2010

New baseline engineering studies

2012Rejected elements

RDR Baseline (VALUE est.)

(RDR ACD concepts and R&D)

39

Minimum Machine Document in Preparation

• Draft document is preparation

• (draft available on PAC website)

• (One) Focus of ILC08 workshop– Study planning– Resources

• Final publication end of year

40

MM Resources for 2009• Need to make estimates of resource (and skill-set) requirements

for the proposed studies– Proposed program will be part of MM 08 report– One of the goals for ILC08

• Must be aware of regional involvement– Not necessarily a strict balance but– Work should be shared across regions where possible

• Do not see this as a resource intensive program– But we must be in a good position for the proposed re-baseline in 2010

• Regional Accelerator Physics & Design “centres”– Cockcroft Institute (UK)– FNAL– KEK– SLAC– …

• CFS resources an issue– 3D-CAD layout etc.

Needs

Attention!Needs

Attention!

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Summary

• RDR design represents a solid and relative detailed baseline on which our current cost estimate is based

• Assumption that design is ‘conservative– potential opportunities for significant cost reduction– Primary target for machine designers: reduction of

underground volume!• Minimum machine accelerator physics/design

activities for 2009– Formal re-baseline in early 2010 for TD Phase 2

activities– Guesstimate ball-park savings ~1 BILCU– (In parallel with critical risk-mitigating R&D)

• MM document defining scope and detailed 2009 study plans to be published after ILC08

• 2009 resources are an issue and need close scrutiny

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Marc Ross Nick Walker Akira Yamamoto 1 st PAC Meeting 19 th October, 2008 Machine Design & Cost Reduction Activities 1.

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