ILC Test Facilities

1
ILC Test Facilities

• Sergei Nagaitsev
• Fermilab

2
International Linear Collider

• New energy frontier machine proposed for HEP
• Parameters
• Electron-Positron Collider
• Ecm adjustable from 200 500 GeV
• Luminosity ? ?Ldt 500 fb-1 in 4 years
• Energy stability and precision below 0.1
• Electron polarization of at least 80
• The machine must be upgradeable to 1 TeV

3
Overview

• The ILC is based upon a Superconducting Radio
  Frequency (SRF) linacs of unprecedented scope (
  length23 km, 1680 Cryomodules, 14,560 SRF
  cavities, 31.5 MV/m)

30 km
4
ILC ML Beam Parameters
Average beam power is 11 MW / beam ? wall plug to
beam efficiency is crucial ? Superconducting RF
5
ML basic building block
ILC RF Unit 3 CM, klystron, modulator, LLRF
Baseline design now has 2 CM with 9 cavities, 1
CM with 8 cavities quad
6
Issues for ILC linac

• Key issues for ILC Physics
• Machine Energy, Luminosity, Availability
• Technical Challenges
• Achieving high gradient in SRF cavities with a
  reproducible process
• Building cryomodules with these cavities that
  meet ILC specification
• Developing a reliable and efficient RF power
  source
• Transport and focus beams at the IP
• Industrialization of high volume components
• Cost !
• The Global Design Effort is addressing these
  challenges via a worldwide RD program with
  specific goals (see M. Ross talk)
• Key to achieving these goals are evolving ILC
  Test Facilities, the subject of this talk

7
Task Forces

• S0/S1 Cavity and cryomodule
• S2 RF unit system tests
• S3 Damping Rings
• S4 Beam Delivery System
• S5 Positron Source
• S6 Controls and LLRF
• S7 RF sources

8
Major International Test Facilities

• Damping Rings
• ATF, CESR-TA, KEKB, PEP-ii
• S3 Electron cloud ions low emittance kickers
• Main Linac
• FLASH, XFEL, STF, ILC-TA, ESA, Zeuthen
• Rf unit heat loads HOMs LLRF rf sources
• S2, S6, S7
• BDS
• ATF2, ESA
• S4 FFS MDI design Small spot tuning

9
Cavity and Cryomodule Goals

• The GDE has established project wide RD goals
  for ILC cavities and cryomodules
• S0 goal Establish a process controls to
  reliably achieve 35 MV/M in bare cavity tests
  (80 yield)
• S1 goal Complete an ILC Cryomodule with all
  cavities at working at accelerating gradients
  gt31.5 MV/M (Average)

10
SCRF Infrastructure

• Bare cavities
• Fabrication facilities (Electron beam welder, QC,
  etc)
• Surface treatment facilities BCP Electro-polish
  facilities (EP)
• Ultra clean H20 High Pressure Rinse systems
• Vertical Test facilities ( Cryogenics low power
  RF)
• Cavity Dressing Facilities ( cryostat, tuner,
  coupler)
• Class 10/100 clean room
• Horizontal Test System (cryogenics and pulsed RF
  power)
• String Assembly Facilities
• Large class 10/100 clean rooms, Large fixtures
• Cryo-module test facilities
• Cryogenics, pulsed RF power, LLRF, controls,
  shielding, etc.
• Beam tests ? electron source (RF unit test
  facilities)

11
Cavity/CM process and Testing
Plan Develop in labs then transfer technology to
industry
12
Damping Rings

• The ATF at KEK has or will demonstrate many/most
  of the outstanding issues
• Low emittance operation
• Intra-beam scattering
• Ion instabilities
• Instrumentation development
• Main outstanding issue is the electron cloud
• Studies at PEP-II, KEKB, and CESR
• Very international program

13
ATF Prototype Damping Ring
14
ATF Prototype Damping Ring

• Ongoing effort with effort from SLAC, FNAL,
  Cornell, and LBNL
• ATF has been operating since 1997
• Low emittance beams at 1.3 GeV
• Many opportunities
• Instrumentation and feedback development
• Tuning studies
• Ion instabilities
• Kicker system demonstrations
• Large SLAC involvement since 1992
• Big UK effort with FNAL and Cornell

15
Electron Cloud Studies

• Experimental programs at PEP-II and KEKB
• Driven by ILC and Luminosity-factories
• Extensive benchmarking of codes
• Studies of cloud suppression techniques in
  dedicated vacuum chambers
• Coatings and grooves
• Understanding cloud generation
• No plans for a system test which would need
  rebuilding the vacuum systems
• System tests at CERN and Frascati

16
KEK-B and PEP-II

• Separate problem calculate instability threshold
  and electron cloud generation
• Experiments aimed at latter quantifying
  techniques to suppress the cloud generation

PEP-ii Chamber tests
KEK-B E-cloud Tests
PEP-ii Sample test
17
CESR-TA

• CESR-TA would be a dedicated DR test facility
• Positron beams ? testtechniques to
  suppresselectron cloudgeneration
• Study effect in wigglers whereexpected to
  bemost important
• Needs further consideration

18
Linac Test Facilities

• S0/S1 is coordinating the cavity development
• S2 provided advice on Linac System Tests
• Regional programs STF, ILCTA-NML, FLASH
• Scoped at the 1 to 2 rf unit level
• XFEL will also demonstrate many systems level
  issues
• Plans for rf systems tests
• ESA and Zeuthen

19
S2 Task Force
20
S2 Questions

• Single rf unit tests
• Check what gradient spread can be handled by the
  LLRF system.
• Check for heating due to high frequency HOMs.
• Check amplitude and phase stability of the RF
  with respect to the beam.
• Check static and dynamic heat loads
• Other tests
• Beam dynamics cannot be tested reasonably
• Statistical effects like reliability and dark
  current are hard

21
DESY RD Activities
Europe
The TESLA collaboration centered at DESY
developed the SRF technology adopted for ILC.
DESY is the world leader

• Cavity RD
• 9 cell TESLA shape (baseline for ILC)
• Electropolishing development
• Large grain Nb, hydroformed
• Cryomodule and RF power Development
• TTFII/Flash RF unit test facility for XFEL
• Industrialization of SRF technology

22
TTFII/FLASH/XFEL (DESY)
Europe

• TTFII/FLASH
• TTFII was originally a test facility for TESLA
  (ILC)
• TTFII SRF linac now drives VUV-FEL (FLASH)
  providing light for BES users
• Machine time still available as ILC test facility
  
• XFEL (European Project)
• Recently approved for construction at DESY
• 20 GeV SRF linac driven light source
• DESY Facilities (ramping up in support of XFEL)
• Cavity fabrication, processing, test facility
  upgrades
• Cryomodule fabrication ? industrial training for
  XFEL

23
FLASH Overview
Europe
RF gun
Laser
24
FLASH uses TESLA CMs
Europe
25
Performance of Recent CM 7
Europe

• Recent CM experience
• CM 6 had 5 cavities over 30 MV/M ( but 2 went
  down WRT HTS)
• CM 7 had 6 of 8 cavities above 30 MV/M (
  encouraging)

26
TTFII/FLASH
Europe

• ILC related performance
• Operations 13 unscheduled down time (mostly RF
  sys)
• Phase stability 0.14o of 1.3 GHz or 300 fs
• dE/E 2.4 10-4 measured at 127 MeV
• Plans
• Add 6th CM, beam energy ? 1 GeV/c
• Improve electron gun (reduce dark current)
• Add 3rd harmonic CM (FNAL), doubles FEL light
  output
• FLASH operations, ILC studies, Construct XFEL !!!
• 30 of time is available for Accel dev and ILC
  RD

27
XFEL RF Test Facility
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STF (Asia)
Asia

• Superconducting Test Facility (STF)
• Location KEK, Japan
• Purpose General SRF test facility in support of
  the ILC
• Status Under construction
• Facilities
• Cavity fabrication, processing, test
• ILC module fabrication
• ILC module test facility
• Plan Evolve into RF unit test facility

29
STF Facility KEK
Refrigerator
Control Room
Klystron Gallery
Clean Rooms
EP Facility
Cryomodule Assembly
HPR
30
STF (Superconducting Test Facility)
31
STF (Superconducting Test Facility)
32
STF RD Activities ( Asia)
Asia

• Cavity RD
• 9 cell TESLA shape (baseline for ILC)
• 9 cell Ichiro cavities (goal higher Eacc)
• Seamless cavities (hydroformed)
• Single cell EP RD
• Cryomodule RF Power development
• ILC RF unit test facility
• Industrialization of SRF technology

33
Cavity RD at KEK
Asia

• 4 Tesla Shape cavities
• Processed and vertical tested
• 3 cavities achieved 20 MV/m
• 1 achieved 30 MV/m, installed in CM
• Performance limited by field emission

• 4 Ichiro cavities
• Reentrant design lowers B at fixed Eacc
• Single cells 6 examples all gt 40 MV/M
• But so far 9 cells are only 12-20 MV/M
• Limited by multipacting in end groups
• End groups removed?1 achieved 29 MV/M
• One 19 MV/m Ichiro cavity installed in CM

EP
40
34
STF Plan
Asia

• Phase 1 (2005-07) Develop SRF cavities
  infrastructure
• Two types of cavities TESLA and Ichiro (35 ? 45
  MV/m)
• Start with two 4 M cryostats (access to STF
  tunnel)
• 1 cavity in each short cryostat Now !
• 4 cavities in each short cryostat Sep 2007
• Improved cavities
  Apr 2008
• Phase 2 (2008 10) Develop ILC Main Linac RF
  unit
• Built Cryomodule test facility
• CM Fabrication
  2009-10
• Build RF power test infrastructure now-2010
• RF unit test
  2011
• In parallel with phase 1,2
• GDE S0 task force (demonstrate 35 MV/M gradient)
• Industrialization

35
Plan of STF Phase 2 beam line
Asia
65m
36m
Toshiba

• Phase 2 Beam ( 2011)
• 2 SC beam capture cavities
• RF gun, ( collab with FNAL)
• Bunch charge, structure, and current similar to
  ILC

Existing Short Cryomodules
36
RD Activities (Americas)

• Cavity RD
• 9 cell TESLA shape (baseline for ILC)
• Large grain Nb (TJNL, FNAL)
• Electropolishing (Cornell, TJNL, ANL/FNAL)
• Cryomodule design fabrication (FNAL)
• RF power development (SLAC)
• ILC RF unit test facility (FNAL)
• Industrialization just starting

37
U.S. Cavity RD National effort
JLab
Cornell
Electropolish

• Several cavities
• gt 30 MV/m in vertical test

Vertical EP
ANL/FNAL Collaboration
FNAL New Vertical Test Facility TESTED 1st
cavity on 07/24/07
ANL New clean rooms, state-of-the-art EP
38
VCTF in Industrial Building 1
VTS pit
Existing IB1 cryoplant/infrastructure for Magnet
Test Facility (MTF)

• Significant cost savings faster implementation
• Current replacement value 10M
• Knowledgeable technical staff
• 4 cryogenic magnet test stands
  FY06 tested 29 superconducting magnets
• 3 conventional magnet test stands
  FY06 tested 21 conventional magnets
• Cryogenic engineering, data acquisition systems,
  diagnostic instrumentation, software and data
  management, etc.
• Continue to share cryogenic system and IB1
  infrastructure with magnet test program
• Cryogenically demanding LHC magnet production
  tests are finished

39
VTS Cryostat/Insert Design
Based on Fermilab design of DESY/TTF/VTS Added
phase separator for better quality He
80K shields

Top plate insert
Cryostat
vacuum vessel f42
thermal baffles
5K shield
radiation shielding
16
cavity
heat exchanger
phase separator
helium vessel 26.5
radiation shielding
fiberglass pit liner
cavity
Cryostat manufactured by PHPK Technologies,
Columbus OH
40
Cryostat photos
September 2006 Cryostat ordered January 2007 He
vessel ASME code stamped February 2007 Received
at Fermilab March 2007 Temporarily
installed April 2007 Permanently installed May
2007 Cryogenic Safety Review May 2007 First
cold test and commissioning July 24, 2007 First
single-cell cavity tested!!!
Fermilab
Fermilab
PHPK
41
Horizontal Test System (FNAL)

• After vertical test extensive cavity handling
  ensues
• Cavity welded inside He vessel
• Cavity opened to install main coupler
• Tuner added
• Horizontal Test
• First test of the cavity with high pulsed RF
  power
• RD Test bed tuners (slow), couplers, LLRF, etc.
  
• NEW HTS facility is nearly complete at FNAL

Dressing
HTS Cryostat
1.3 GHz Cavity in HTS Cryostat
RF Power for HTS
42
ILCTA ( FNAL)

• ILC RF unit test facility
• Location Fermilab New Muon Building (NML)
• Goal Address the GDE S2 Goals
• Demonstrate a complete ILC RF unit with ILC-like
  beam
• Also crab-cavity RD, diagnostics development,
  personnel training, and advanced accelerator RD.
• ILC-like beam
• 3.2 nC/bunch _at_3 MHz
• Up to 3000 bunches _at_ 5Hz
• Bunch length 300-µm rms
• Injector Energy 30-40 MeV (to avoid over
  focusing in ILC CM)
• To understand CM need known beam parameters _at_
  CM entrance and exit? good diagnostics

43
Location
New Muon Lab
44
ILCTA_NM (FNAL)
Existing Building
New ILC like tunnel
ILC RF unit
Diagnostics
Gun
3rd har
2nd ILC RF unit
CC I,II
Bunch Compressor
Laser
Test Area
New Building
Test Areas
RF Equipment

• 40-50 Mev Injector
• Well characterized beam
• Low energy test area (e.g. 3.9 GHz Crab cavities)
  
• New bldg for diagnostics AARD
• Also houses new large cryo plant

new 300 W cryo plant
45
Stage 1 1st CM (early CY08)
A used 3 MW Klystron, 10 MW, 1.5 ms modulator
CC2 RF system
Capture cavity 2 in its final location for the
injector
Type 3 cryomodule
46
A0 Photo Injector

• The A0 Photo Injector built in collaboration with
  DESY as part of the TESLA collaboration (
  essentially a copy of TTFI)
• In operation since late 90s
• Two klystron-based RF systems power the RF Gun
  Capture Cavity
• Built a second capture cavity (CCII) using high
  gradient DESY cavity
• A0 RF assets and CCII will be moved to NML in 2008

RF Gun prior to solenoid installation
Capture Cavity and beamline
Capture Cavity-II
47
ILCTA Plans

• Effort is Funding limited? phased approach
• Cryomodule delivery
• 1st (Type 3) cryomodule built from kit of DESY
  parts in late 2007
• 2nd (Type 3) CM 2008 built with U.S.
  processed cavities
• 3rd (ILC Type 4) CM 2009 all U.S. components
• Replace all three CMs with ILC Type 4 in FY2010
• FY07 Start as a Cryomodule Test Stand
• FY08 move A0 photoinjector, start civil
  construction for new bldg
• FY09 1st beam operation, 2-3 CM, low rep rate
  operations
• FY10 replace all 3 CM with ILC type CM
• FY11 install new refrigerator, ILC RF Unit
  operations
• Collaboration DESY, INFN, ANL, Cockroft, NIU,
  Rochester, KEK

48
ILCTA_NML_at_FNAL
Cavities for 1st CM _at_ FNAL
NML June 07
NML Building
1st of 2 refrigerators each 60 W_at_1.8K
Parts for 1st CM at DESY
FNAL Clean Room CM assembly Area
49
A facility to test ILC baseline and alternative
designs

• Many groups in the US and world-wide are looking
  for a place to test their ILC-related designs.
• Need beam at 200-800 MeV, need space to set up
  tests
• Baseline design
• Keep alive positron source (ANL)
• SC undulator (Cornell)
• Crab-cavity (SLAC, Cockcroft Inst)
• Alternative designs
• New HOM coupler design (MIT)

50
Cryomodule Test Stand

• We know we will need it eventually. Need by
  FY2011
• Location yet undetermined
• A 500 sq meters, 32m x 16m, building required.
  Includes some utility and access space
• Much larger than a typical Fermilab magnet test
  stand due to the shielding cave
• Comparable in scope to Stage-1 of NML
• Motivations for cryomodule tests
• Mechanical checks
• Alignment of tubes, flanges, etc.
• Leak checks of all volumes
• Conditioning of main RF-couplers
• Cryo load measurement, Q and Eacc
• SC magnet power test
• Dark current measurements

51
XFEL Module RD Test Stand
From Yury Bozkho, Bernd Petersen (DESY)
52
SLAC ESA RF Test Facility
L-Band Test Stands Existing (green), FY07-08
(blue), FY09 (yellow)
ESA
LCLS
ESB (NLCTA)
53
Beam Delivery System

• See Andrei Seryis talk tomorrow
• The ATF2 at KEK will demonstrate many systems
  level issues in FFS (and others)
• FFS optical solutions
• Beam instrumentation
• FFS tuning and beam line alignment
• High availability power supplies
• SC quadrupoles
• The ESA is used to study MDI issues
• Collimator wakefields
• IR diagnostics and signals

54
ATF2 at KEK

• Demonstrations of
• Optics design
• RF BPMs
• Magnets and movers
• HA power supplies

ILC like optics at ATF-2
New final focus
http//lcdev.kek.jp/ILC-AsiaWG/WG4notes/atf2/propo
sal/public/atf2-web.pdf
55
End Station A at SLAC
3 runs thus farexpect 3 morethrough
FY08 Schedule beyondFY08 is not clear
Collimator design, wakefields (T-480) BPM energy
spectrometer (T-474) Synch Stripe energy
spectrometer (T-475) IP BPMs, kickers EMI
(electro-magnetic interference) IR Mockup
56
Summary

• The International Linear Collider will employ an
  SRF linac of unprecedented scope
• Cavities Cryomodules are cost drivers for ILC
• There are many issues to be addressed to
  demonstrate the required performance for ILC
• All three regions have mounted large RD programs
  to explore these issues
• Extensive infrastructure is needed to support
  this RD and ILC industrialization
• Large scale RF unit test facilities are a key
• Lots of progress ambitious plans