Tor Raubenheimer

SLAC ILC Accelerator Program

DOE HEP Program Review

June 14th, 2005

Outline and Breakouts

• Outline– Program overview– CDR Efforts– L-band RF development

• Breakouts– L-band RF R&D

Adolphsen– e+/e- Source development & E-166 Sheppard– Beam Delivery System & ATF-2 & ESA Seryi– Accelerator operations Tenenbaum– Instrumentation Development Ross– ILC Civil studies & cost issues for Snowmass Asiri

SLAC ILC Program

• SLAC ILC Department is focused on the ILC machine design– Presently the largest group focused on the ILC accelerator design– More than 70% of the ILC is ‘warm’ technology that we know well

• Funding is 16.2 M$ from DOE plus ~0.5 M$ from US-Japan– 2 M$ of the DOE funding is used to support the ILC programs at LBNL,

LLNL, and BNL

• SLAC group has roughly 40 people in ILC Department plus another 40~50 people matrixed across the lab– Nominal program is roughly 65 FTEs – Presently under-running due to redirection from the NLC program,

personnel losses to LCLS, and the accident recovery at SLAC but expect to catch up during summer

SLAC ILC and the GDE

• Barry Barish has been chosen to lead the GDE and Gerry Dugan is the American Regional Director– GDE organization not yet completely clear– Working with Barry and Gerry to formulate FY06 program

• Near term plans from the GDE:– Develop a baseline design in a ‘CDR’ with regional sites by the end of

CY06– Establish an R&D program focused on improvements (cost and

performance) to the baseline design– Use 2nd ILC Workshop at Snowmass to begin definition of baseline

• Barry: “the SLAC group is essential to develop the CDR”– Develop accelerator design with other international groups– Work with Fermilab FESS group on site development in the US

ILC Working Groups and Snowmass

• Goal for 2nd ILC Workshop at Snowmass:– Start making choices for Baseline Configuration Document and determine

remaining work to decide on BCD by 12/05– Develop focused R&D program for cost reduction and/or improved performance– Develop site models for three different regions

• Informal ILC organization will be used for Snowmass– 6 subarea Working Groups with three conveners apiece– Four of the 6 US region co-conveners are from SLAC ILC– Possibly 5 more ‘global’ working groups with possible SLAC leaders– Organization is bottoms-up with coordination provided by Nick Walker, Kaoru

Yokoya, and myself working with the WG conveners

• SLAC ILC group is working on documentation for the meeting that will compare options for the BCD

SLAC FY05 ILC Program

• NLC group was redirected towards ILC– Developed a program aimed at the topics identified in the 2003 Technical

Review Committee report and at the 1st ILC Workshop• Description at:

http://www-project.slac.stanford.edu/ilc/slacprogram.html

– The 2003 TRC identified 1 ‘R1’ and 15 ‘R2’ R&D items • DESY, Fermilab, and KEK are focused on the outstanding R1 and

the R2 on the linac sub-unit test• SLAC is focused on the other 14 of the 15 R2 items and is working

with US labs, KEK, UK groups, and DESY

– SLAC is using technical expertise to study paths for cost reduction• High power rf (klystrons, couplers, circulators, and rf distribution) and

solid state modulators

SLAC FY06 ILC Program

• Program for FY06 has two main elements– Development of the ILC CDR

• Overall design: Beam parameters, Optics, Emittance preservation, Stability/alignment, Instrumentation, Availability, MPS, and Operational issues

• Electron & Positron sources and Damping rings• Linac design and wakefields/cavity optimization• Beam Delivery System and Interaction Region • Conventional construction implications and site development

– Continuing R&D on linac rf technology• Klystrons, modulators, rf distribution, and couplers• Not (much) SC Cavity fabrication

– Plan is posted on SLAC ILC website: http://www-project.slac.stanford.edu/ilc/slacprogram.html

Experimental Basis for the ILC Design

Linac rf system

BDS & IR

DampingRings

e+ / e- Sources

Bunch Compression

SLC, E-158

SLC and(ATF2 in the future)

SLC, FFTB, ASSET, E-158

ATF, 3rd Gen Light Sources, SLC

Preservation

TESLA Test Facility (SMTF & STF in the future)

SLC and FEL’s

ILC System Design and Operational Issues

• Extensive simulation of sub-systems– Balance emittance budgets and specify system tolerances impact on

overall beam parameters

• Study operational issues– Design for availability and work on detailed availability models big

impact on layouts and configuration but hard to quantify– Develop beam tuning algorithms specify beam instrumentation

requirements and layout– Consider high-level controls software requirements (applications) for

beam control specify control system requirements

• Develop Machine Protection Scenarios– Specify active and sacrificial protection systems– Specify beam tuning stations

Electron and Positron Sources

• Electron source– Continuing photocathode development– Creating space to begin laser and gun development– Need to start design simulations

• Positron source (program with LLNL)– Studying target design for undulator, conventional, and Compton

sources• Radiation damage• Thermal shock / beam damage• Engineering issues (high rotation speed, remote handling)

– Capture and optics studies– Normal conducting capture structure design and fabrication– Complete E-166 polarized positron production (summer 2005)

Damping Rings

• Damping ring design (program with LBNL)– Optics and tuning studies and collective effects

– Bunch compressor design

• SEY studies for electron cloud (program with LBNL)– Laboratory measurements in PEL

– Building three chambers for PEP-II installation to verify solutions

• ATF at KEK– Instrumentation (NanoBPM, laser wires,

optical anchor)

– Beam studies (ORM, BBA, FBII, Wiggler)

– ATF Kicker replacement

– ATF stripline kicker development

– FONT/Feather

3ns kicker from LLNL/SLAC

Damping Ring Optics

• New optics proposed based on PEP-II non-interleaved sextupole correction Pi-cell and FODO cell designs

TME (DESY TDR) Pi-cell (low Pep-II) FODO (high Pep-II)

Injected positron beam: x = y = 1x10-6 m-rad, tracked using LEGO with single-mode wigglers and multipole errors in the other magnets.

Dynamic aperture in Dogbone Damping Ring designs

Electron Cloud Simulations

Electron density in units of e m3 as a function of time for an arc bend in the 6km DR option assuming a beam pipe radius 22mm and including an antechamber design (full height h=10mm).

Electron density in units of e m3 as a function of time for an arc bend in the 6km DR option assuming a beam pipe radius 22mm and including an antechamber design (full height h=10mm).

SEY Studies in PEP LER

• Building three chambers for PEP-II– One with a load-lock system to allow laboratory measurement of a

sample after exposure to the PEP-II vacuum environment – Two ‘grooved’ chambers to verify a proposal by Mauro Pivi and

Gennady Stupakov

Linac Beam Line Design

• Quadrupole alignment– Use a SC linac quadrupole from DESY to study shunting alignment ability

– very important to achieve desired tolerances– Continue program for NC quadrupoles

• BPM tests (program with TTF, ATF and LCLS)– Develop and test high resolution BPMs

• Laser wire (program at ATF and PETRA3)– Work with other groups to test high resolution laser wires

• Cavity diagnostics (program at TTF)– Add HOM detectors to SC cavities at TTF to determine beam-cavity

location – very important especially for high shunt impedance cavities with small aperture

• Measure vibration due to SC cryogenic equipment– Important for conventional layout and BDIR

Beam Delivery System

• Optics design and layout (program with UK groups)– Study variations of BDS with different crossing angles, collimation systems, L*,

etc understand tradeoffs

• ATF-2 at KEK– Demonstration of new FFS using ATF beam– Proposal is being assembled – detailed contributions to be defined

• Specialty magnets (program with BNL)– SC final quadrupoles are being prototyped at BNL

• End Station A Test Facility (with UK and University groups)– MDI instrumentation studies, collimator wakefield studies– Construct IR mock-up

Civil Construction and Sites

• Working with the Fermilab team to develop an Illinois site and a reference site– DOE has urged consideration of an Illinois site but it is important to

understand the advantages and disadvantages

– For Snowmass

• Investigate 5 possible Illinois sites and create a matrix to compare sites

• Investigate cost of configuration options

– For BCD (December 2005)

• Select Illinois site and compare withreference site; submit to DOE

– For CDR (December 2006)

• Develop selected Illinois site with cost and schedule

Project Management

• Need to establish configuration control for the ‘CDR’ and subsequent TDR– Ewan Paterson is putting together a proposal to manage

• The collider configuration • Collider construction project cost and schedule • Possibly the R&D program cost and schedule

– Barry Barish will create configuration control board • Members from the accelerator design team• Members from the engineering team

• Need to structure the ‘CDR’ work and work packages– Many discussions but need to move forward before Snowmass

• Need to establish a structure for the BCD documentation– 1st cut being made by Nick, Kaoru, and myself

L-Band RF System R&D

• SLAC has strong expertise in rf power generation and lots of experience from the X-band rf program to apply to ILC– Goal: reduce cost of the rf system (which is roughly 15% of TPC in

USLCTOS cost estimate) and improve performance (better reliability, higher efficiency, …)

• Working on solid state modulators, L-band klystrons, and other rf components– Many of these components could be part of the BCD – if not should be part

of the long-range R&D program

• Collaborating with Fermilab on three projects for the SMTF: – Modulator switches – Bayonet box for cryo-system– Electron-beam welding of SC cavities

Modulator R&D

• Baseline design is FNAL/DESY/PPT modulator• Single switch with bouncer circuit and 12:1 transformer

• Efficiency is pretty good; reliability uncertain; transformer is large and stray fields impact the dogbone damping ring

• SLAC effort is evaluating options– Receiving an SNS power converter-modulator which should have

good efficiency – Building Marx generator style which should provide similar efficiency

and 100% availability and lower cost

– Building switch for FNAL bouncer-style modulator– Working with Diversified Technologies in SBIR program (??) to test

another series-switch modulator

– Looking at high voltage cables for power distribution

Klystrons

• Three industrial vendors for ‘baseline’ 10MW MBK tubes– Still very little real experience with multi-beam klystrons– Thales has delivered two refurbished tubes to DESY– CPI 10MW tube was accepted by DESY – may come to SLAC later– Toshiba 10MW tube is still under test

• Four elements to SLAC program– Develop L-band sheet beam klystron– Study klystron / modulator options

• More conservative 5MW tube or lower power PPM tubes• Decide which (if any) of these to pursue further

– Buy L-band rf power at SLAC (needed for experience and other elements of program)

– Possibly work with DESY and CPI on CPI 10 MW tube

Other RF Topics

• Large number of ideas and requests for help– Constructing an SC

‘materials’ test facility

– Studying TTF3 coupler designs and limitations

– Looking at new approachesfor the rf distribution that would reduce the number of components

– Working on concepts for new high power circulators and industrialization of low power (400 kW) circulators

Major Test Facilities

• End Station B– Complete X-band program in NLCTA– Create new L-band rf Test Facility

• Develop klystron and modulators for ILC• Test normal conducting structures for e+/e- sources• Construct coupler test facility

– Facilities also available in Klystron Test Lab

• End Station A– Study Interaction Region issues and instrumentation– Mockup of full IR

• ATF/ATF-2 (Located at KEK but with big SLAC participation)– Test final focus system using very low emittance beam

• Work on the linac test facilities around the world: TTF, SMTF, and STF

End Station B Program

• NLCTA completed restart review and will turn on this week

• Complete X-band program at NLCTA– Test CERN structure and other gradient studies

– Test active switching technology

– Will decommission 8-pac modulator and install a 2-pac modulator to allow for future use of the 300 MeV X-band linac

• Create facility to construct prototype collimators for the LHC– Adaptation of NLC consumable collimator technology to allow the LHC to

reach design luminosity (part of US-LARP)

• Support E-163 laser acceleration experiment

• Start construction of an ILC L-band test facility next slides

End Station B L-Band RF Test Facility

• Build two L-band test stations next to NLCTA in ESB– Test modulators and klystrons– Provide rf power for NC accelerator structures and couplers

Longer Term L-band RF R&D Goals

• All stations in End Station B will be run 24/7• FY06:

– Complete 1st station for rf component testing and experience– Test normal conducting structure for positron system– Develop coupler test stand– Start testing of circulators and other rf components

• FY07: – Complete 2nd station to test Marx Generator (and CPI klystron?)– Test couplers for SMTF at Fermilab

• FY08:– Finish 3rd and 4th stations with improved modulator/klystron designs

• FY09:– Construct 10 additional stations in ESA or Klystron Test Lab to begin

industrialization process, lifetime testing, and optimization

End Station A Test FacilityEnd Station A Test FacilityFor Prototypes of Beam Delivery and IR ComponentsFor Prototypes of Beam Delivery and IR Components

CCLRC LLNL QMUL U. of Bristol UMass Amherst

CERN Lancaster U. SLAC UC Berkeley U. of Oregon

DESY Manchester U. TU Darmstadt U. of Cambridge

KEK Notre Dame U. of Birmingham UCL

http://www-project.slac.stanford.edu/ilc/testfac/ESA/esa.html

Collimator design, wakefields (T-480)BPM energy spectrometer (T-474)Synch Stripe energy spectrometer (T-475)IP BPMs, kickersEMI (electro-magnetic interference)IR Mockup

PAC05 paper/poster: SLAC-PUB-11180, e-Print Archive: physics/0505171

ATF-2 at KEK

• ATF-2 would be the BDS test facility– Follow-on to FFTB– New FFS optics– Operational issues– Train next generation

Reasons to develop the ATF-2

• Many reasons to develop the ATF-2– Luminosity issues will be extremely challenging in the LC

• Likely more challenging than achieving the beam energy

– Complete FFTB studies• FFTB never demonstrated routine operation of FFS• Need to implement full feedback control and optimization• Operate with ILC like bunch train and demonstrate IP feedback• Operate with stable low emittance beam from ATF DR

– Provide demonstration and experience concurrent with ILC construction• FFTB experience will be over 15 years old• Train new generation of physicists• Provide a visible test facility for project reviewers and sponsors

Collaborative Meetings

• ILC Status Meeting – bi-weekly: SLAC, ANL, BNL, Cornell, Jlab, FNAL, LBNL, LLNL

• Availability and MPS – monthly: SLAC, DESY• LET – bi-weekly: SLAC, Cornell, FNAL• e+ source – bi-weekly: SLAC, LLNL

– @ Daresbury wks – SLAC would lead CDR effort

• DR – bi-weekly: LBNL, ANL, Cornell, FNAL, SLAC – E cloud – weekly: SLAC – also irregular with LBNL, CERN, and KEK– ATF– irregular: SLAC, Cornell, LBNL, LLNL, UK

• BDS – weekly: SLAC, BNL, FNAL, Oregon – also monthly: EU & Japan– MDI – monthly: SLAC, FNAL, Orsay, UK, many US universities– ESA – weekly: SLAC, UK, universities– ATF2 – irregular: SLAC, KEK, UK

• Instrumentation – irregular: SLAC, KEK, DESY• SMTF – biweekly: SMTF collaboration• Conventional facilities – weekly: SLAC, FNAL

SLAC ILC Budget

• FY05 DOE ILC budget is 22.7 M$– 16.2 M$ to SLAC– 1.95 M$ LBNL, LLNL, BNL– 14.25 M$ at SLAC plus US-Japan

funds

• FY06 DOE budget is 25 M$– Distribution is unknown– Developing a detailed plan for FY06 based on 14.25 M$ at SLAC and 3.8 M$

LBNL, LLNL, and BNL plus 0.5 M$ US-Japan funds• Working with Robin Staffin, Barry Barish, and Gerry Dugan • Maintain flexibility to deal with budget increase or decrease

– Having difficulty keeping people on ILC given the uncertainty• Lost 10 people so far in FY05

FY05 Funding Source M$

DOE ILC Program +16.2

US-Japan Program +0.87

Xfers to LLNL, LBNL, BNL -1.95

SLAC Labor 8.3

SLAC M&S / Shop 2.9

SLAC indirect overhead 3.1

Carryover change FY06 – FY05 0.8

Summary

• Last year has been difficult– Technology choice forced redirection of effort– Major accident and subsequent shutdown– Budget shortfall and layoffs in FY05 and large uncertainty in FY06

• Strong program addressing many of the critical design issues– SLAC program addresses 14 of the 15 “R2” items identified by the 2003 TRC

report as well as many additional problems• Program descriptions for FY05 and FY06 are posted on web site• Working with GDE to further develop FY06 program

• Program is focused on overall accelerator design issues as well some technology development concepts– Makes use of SLAC expertise to lead ILC design efforts worldwide– Many programs could grow but some will require new people