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