Upload
gerard-manning
View
215
Download
0
Embed Size (px)
Citation preview
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
ILC Reference Design
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
ILC Reference Design
• 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
9
Cost (VALUE) Estimate
10
CFS identified as a major cost driver with high-potential for cost-saving
CFS requirements driven by machine design & layout
Cost (VALUE) Estimate
11
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)
12
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)
13
“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
14
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)
16
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
17
Identified Minimum Machine Elements
18
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
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”20
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
21
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
22
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”23
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)
24
SLAC
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”25
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
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”27
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 $$$$
28
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
29
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
30
SLAC
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”31
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)
32
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
33
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’– …
34
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’– …
Requires CAD (CFS) engineer(s), optics (accelerator physics) expert(s).Look for a (conceptual) engineering solution.
35
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’– …
Much more difficult to quantify.Looks for experienced expertsBrainstorm qualitative concepts (solutions)
36
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’– …
FTE and MS required.Well defined goals for R&D programme.Acceptance criteria of proposed solution.
37
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’– …
Beam dynamics and simulation specialists (lc experts).(good coordination, well defined questions)
38
(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!
41
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
42