srf plans at anl & fnal bob kephart ilc program director, fermilab anl-fnal-u of c collaboration...
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SRF Plans at ANL & FNAL
Bob KephartILC Program Director, Fermilab
ANL-FNAL-U of C Collaboration Meeting
Oct 12, 2009
Superconducting Radio Frequency
• Superconducting Radio Frequency is an “enabling” technology relevant for any of a number future accelerators at FNAL and ANL
• Both institutions have near-term and long-term aspirations to build/upgrade SRF based accelerators– FNAL: Project X, ILC, Muon Collider
– ANL: ATLAS upgrades, ILC, future SRF based light sources
• ANL SRF group: long & distinguished history (ATLAS)
• FNAL is new at SRF: but effort has grown rapidly natural for us to collaborate
• Both institutions are expanding SRF infrastructure
May 18-19, 2009 2
ILC = International Linear Collider, 500 GeV e+e- colliderProject X = New multi-MW proton source at Fermilab
ANL-FNAL collaboration on SRF
History:• 2005: choice of SRF technology for the ILC
– Gave a strong impetus to ongoing ANL-FNAL SRF collaboration as part of the TESLA Collaboration (3.9 GHz cavity processing at ANL)
• 2006-8 – EPP2010 and HEPAP strong endorsement of ILC R&D– Emphasis by the Global Design Effort on cavity gradient & yield– Realization: U.S. must master ILC SRF technology (developed @ DESY)– Fermilab also had a growing interest in Proton Driver Project X
• Intense proton source for long baseline neutrinos• Joint design effort with ANL (Peter Ostrumov)• Px uses ILC cavities, gradient lower but yield important• Also uses spoke resonators developed at ANL
– Development of an ANL/FNAL cavity processing facility at ANL – Development of complementary SRF infrastructure at FNAL
• 2009-present – Lots of progress, commissioning infrastructure!
ILC R&D Mission & Goals
Mission (both ANL and FNAL):• Work with the GDE Americas Regional Team (ART) to develop the
ILC design & gain approval of the project
Goals:• Participate in the Technical Design Phase (now 2012)• Participate in Accelerator Physics, Conventional Facilities
Design, and global systems work to further the ILC design• Work towards GDE SRF goals
– S0: Cavity gradient of 35 MV/m; good yield
– S1: Cryomodules with average gradient > 31.5 MV/m
– S2: One or more ILC RF unit with ILC beam parameters
• Perform R&D and value engineering to reduce costs• Become a trusted international partner
SRF !
Project X R&D Plan
• Goals: – Pick configuration in Early 2010– Complete baseline design, cost and schedule estimates in 2012 – Technical component and infrastructure development
• Linac (325 MHz)– High speed variable chopping patterns (325 MHz)– SRF spoke resonator development– RF control of multiple SRF cavities from single klystron
• Linac (1.3 GHz)
– SRF Cavity & CM development coordinated with ILC– 25 MV/m gradient with good yield – ICD-1: (20 mA average) x 1.25 msec x 2.5 Hz
• 3 times the charge/pulse of ILC– ICD-2: ILC cryomodules operated with CW
• 2-8 GeV linac requires 20 ms 1 ma pulses
• H- transport, multi-turn injection, space charge, e-cloud, civil, etc
SRF !
Electropolished 9-cell Cavities
0
10
20
30
40
50
60
70
80
90
100
>10 >15 >20 >25 >30 >35 >40
max gradient [MV/m]
yie
ld [
%]
combined upto-second-pass test of cavities from qualified vendors - ACCEL+ZANON (21 cavities)
1.3 GHz Joint Development Strategy
U.S.
• Project X shares 1.3 GHz technology with the ILC– Project X requires 20-52 ILC-like cryomodules.
• In detail they will not be identical to ILC:
• Gradient: 25 MV/m (but try for higher)
• Yield is important for the cost
• Close coordination of Project X & ILC R&D– Developing U.S. cavity vendors – Cavity gradient and yield!– U.S. results mostly from JLAB– New ANL-FNAL infrastructure will
double U.S. process and testing
• Px 4 year construction 1 CM/month
– Building extensive infrastructure at FNAL, JLAB, ANL, etc for both Project X and ILC R&D
ILCPx
Cavity FabricationBy Industry
Cavity Dressing &Horizontal Testing
@ Fermilab
SurfaceProcessing @ Cornell
SurfaceProcessing
@ Jlab
SurfaceProcessing @ ANL/FNAL
Vertical Testing @ Cornell
Vertical Testing @ Jlab
Vertical Testing @ FNAL
Exists
Developing
~10/yr ~50/yr ~50/yr
ILC R&D (Px) elliptical cavity processing
Plan in Place since 2006
ILC: Cavity processing at Argonne
Electropolishing
High-pressurerinse
Ultrasonic CleaningJoint facility built by ANL/FNAL collaboration2000 ft2 facility @ ANL complete Mar 2009Commissioning, excellent single cell resultsEP processing of 9-cells has startedTogether with JLab are the best cavity processing facilities in the US for ILC or Project X
Chemistry room and new test cryostat
9-cell ElectropolishingNew test cryostat at ANL
ILC: 2 Kelvin Testing for ILC and other SRF Cavities
New large test cryostat system (TC3) is being commissioned at ANL Useful for testing a broad range of ILC and Project X cavities
Final Assembly
HTSVTS
String Assembly MP9 Clean RoomVTS
1st U.S. built ILC/PX Cryomodule 1st Dressed Cavity
Cavity tuning machine
New FNAL SRF infrastructure
HINS 325 MHz Single Spoke Design Parameters
* Eacc is the total accelerating voltage divided by Leff, where Leff = (2/3) = 135 mm, the distance between the edges of the accelerating gaps at the two endwalls.
Quantity Value
Operating temperature 4.4 K
HINS accelerating gradient, Eacc *
10 MV/m
Q0 at accelerating gradient
> 0.5x109
Beam pipe, Shell ID 30 mm, 492 mm
Lorenz force detuningcoefficient
3.8 Hz/(MV/m)2
(with He vessel)
Epeak/Eacc * 2.56
Bpeak/Eacc * 3.87 mT/(MV/m)
G 84 Ω
R/Q0 242 Ω
Geometrical Beta, βg 0.21
SSR1-02,the 2nd SSR1
prototype.Fabricatedby Roark.
OriginalPlan
HINS: A pair of FNAL single spoke cavities processed at ANL
Chemical polishing, high-pressure rinsing in G150 by Argonne and Fermilab SRF staff Cold testing performed at Fermilab Both cavities have achieved world leading performance
1.E-02
1.E-01
1.E+00
1.E+01
1.E+07
1.E+08
1.E+09
1.E+10
1.E+11
0 5 10 15 20 25 30 35
Radiation (mR/hr)
Q0
Eacc(MV/m)
Q @ 2K Q @ 4K after 2K run
Radiation @ 2K Radiation @ 4K after 2K run
Jump thru MP barrier from 24 to 33MV/m
MP from ~11 MV/M
Q0 .vs. Eacc and x-ray intensity as measured at the top of the VTS
Spoke Resonator VTS of bare cavity
Project XOperating
Point15 MV/M
@2 K
New RF Unit Test Facility at Fermilab
An important facility for both Project X & ILC R&D1st Cryomodule moving to NML
1st Cryomodule Test fit Large Vacuum Pump
Control Room He Refrigerator
Progress at NML
CM Feed Can
Capture Cavity II @ NML
RF Unit Test Facility at NML
New buildings and Refrigerator (ARRA)
Broad collaborative SRF materials R&D Program
Pits appear after EP !
• Collaboration of ANL,FNAL,U of C materials scientists!
– See Prolier, Sibener, Cooley talks
• Example– Cavities often limited by
defects near EB weld– Pits observed in
samples after EP. Why?– Diagnostic tools !
SRF: New Temperature Mapping
Traditional carbon resistor based system
New diode based system with 960 sensors and 62 wires can be installed in about 15 minutes
New single-cell temperature mapping system uses multiplexed diodes as sensing elements
• KEK/Kyoto inspection system delivered, installed, commissioned early in 2009
• Expert assistance to optimize system in March 2009• In routine use; software development underway
SRF: Optical Inspection System
Accel7 on the optical inspection stand Optical inspection optimization
SRF: Laser Melting of Nb Surface
• Preliminary experiments show a pit cannot be removed by BCP or EP, even after ~150 um removal
• Fermilab is investigating: Laser Melting
14 µm100 µm
Summary
• Strong collaborative partnership on SRF has grown between ANL, Fermilab, and U of Chicago
• Extensive SRF infrastructure being built at both ANL and FNAL
• Starting to make significant impact on projects
– ILC, Project X, etc (Results at SRF09 in Berlin)
• Collaboration in SRF materials & surface science
– Many complementary skills and facilities
– A success story!
• A good collaboration ? Yes! The whole is greater than the sum of the parts
extras
Project X: What is it?
• A new multi-MW Proton Source under development at Fermilab.
• Enables a world-class Long Baseline Neutrino Experiment (LBNE) via a new beam line pointed to DUSEL in Lead, South Dakota.
• Enables a broad suite of rare decay experiments
Currently two versions of this machine are under consideration.
• Both versions provide 2 MW of beam power to LBNE
• ICD-1 is based on a pulsed 8 GeV 20 ma ILC-like H- SRF linac
• ICD-2 employs a 2 GeV 1 ma CW SRF linac that accelerates H- or P’s
– Provides an additional 2 MW to the high intensity program
• Very flexible beam manipulation via RF separators
– 2-8 GeV = either a pulsed linac or a rapid cycling synchrotron.
Project X website: http://projectx.fnal.gov/
ICD-1 SRF Linac Technology
Most ~ 7/8 of LINAC is built of ILC-like CM but ~ 25MV/M gradient