SMTF Beta <1 Front End LinacInfrastructureand Plans

GW Foster Sept 29, 2004

Beta <1 Test Area(s)

1. TESLA-compatible beta<1 SCRF linac• 325 MHz Pulsed Spoke Resonators

• TESLA-like RF fan out from single Klystron

• Fast ferrite phase shifters demo with beam

2. Possible RIA Production Test Area• to be discussed in Ken’s talk

Beta<1 Linac R&D Goals1. Collaborative Development of a Family of

TESLA-compatible beta<1 cryomodules• 1300 MHz beta<1 and 325 MHz spokes• design standard for future linacs?

2. Demonstrate the TESLA RF fanout for beta<1 SCRF linacs

• requires fast ferrite phase shifters and advanced LLRF control algorithms

• Crucial R&D item for SCRF Proton Driver• This R&D very useful for ILC as well

Proton Driver - 0.5 MW with TESLA Frequencies & SCRF F.E.

RFQRFQ

Modulator

H -

B=0.47 B=0.47 B=0.61 B=0.61 B=0.61 B=0.81 B=0.81 B=0.81 B=0.81 B=0.81 B=0.81 B=0.81

Modulator

"Pulsed RIA" SCRF Linac 325 MHz 0 - 120 MeV

Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1

Modulator Modulator

12 Klystrons (2 types) 11 Modulators 20 MW ea. 1 Warm Linac Load 54 Cryomodules~550 Superconducting Cavities

8 GeV 0.5 MW LINAC

8 Klystrons288 cavites in 36 Cryomodules

2 Klystrons96 cavites in 12 Cryomodules

Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1

Modulator Modulator

Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1

Modulator Modulator

Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1

Modulator Modulator

Modulator

48 cavites/ Klystron

36 cavites/ Klystron

TESLA Klystrons1300 MHz 10 MW

"Squeezed TESLA" Superconducting Linac1300 MHz 0.087 - 1.2 GeV

"TESLA" LINAC 1300 MHz Beta=1

SSR SSR SSR DSR DSR DSR

Multi-Cavity Fanout at 10-20kW/cavityPhase & Amplitude Adjust via Fast Ferrite Tuners

TESLA Klystrons1300 MHz 10 MW

325 MHz Klystrons1.5 MW

325 MHztest area

1300 MHztest area

ILC

Two Design Points for 8 GeV LinacInitial: 0.5 MW Linac Beam Power

8.3 mA x 3 msec x 2.5 Hz x 8 GeV = 0.5 MW Twelve Klystrons Required

Ultimate: 2 MW Linac Beam Power25 mA x 1 msec x 10 Hz x 8 GeV = 2.0 MW 36 Klystrons Required

Either Option Supports: 1.5E14 x 0.7 Hz x 120 GeV = 2 MW Beam Power from Fermilab Main Injector

Proton Driver Linac - Technology Flow

RFQ

“PULSED RIA”SCRF SpokeCavity Linac

“SNS / RIA”Beta < 1 Elliptical

Cavity Linac

“TESLA”Elliptical Cavity SCRF Linac

Beta = 1 1300 MHz

JHF(KEK)

RIA (ANL)APT (LANL)

SNS (JLAB)RIA (MSU)

FNALANL / SNS

New FNAL Proton Source Linear Collider Test Facility

TESLACOLLABORATION

BNL / SNS

FNAL Proton PlanUpgrades

NUMI Beamline & Infrastructure

H_

325 MHzRFQ andKlystron

SCRFSpoke

Cavities

LinacAccel.

Physics

SNSProductionExperience

β < 1Cavity

Design

FastFerrite

Shifters

PulsedModu-lators

Cavities

Cryogenics

Klystrons

RF

Distribution

Beam Transportand CollimationDesign

MainInjector@2 MW 8 GeV beams:

P, n, ν, µ, e…Technological& HEP Applications

Neutrino Super-beams

Other Labs & Universities

PROTON DRIVER

8 GeV1.3 GeV

JHF 325 MHz RFQ and Klystrons for TESLA-Compatible* Front End

JHF 325 MHz RF Quad JHF 325 MHz3 MW Klystron* TESLA frequency = 1300 MHz

= 4*325 MHz

LANL (APT) ANL (RIA)

Modulators at SMTF• Alternate designs under evaluation &

design since January ‘04– Switch-mode (SNS type)– Mismatched PFN– FNAL/TTF Bouncer * SELECTED (for cost) *

• Two Modulators under construction– Should be ready in ~ 1 year– Support RF pulse widths of 1.5, 3, 4.5 msec– Significant technological cost reductions

Reconfigurable Klystron ModulatorsModulators can be reconfigured & parts re-used for RF power upgrade scenarios

Pulse Transformer& Oil Tank

IGBT Switch & Bouncer

CAP

BANK

10 kV115 kVCharging

Supply

300kW

Klystron1300 MHz

TESLA MBKor 325MHz

JPARC

4.5 msecx 2.5 Hz

10kV

Pulse Transformer& Oil Tank

IGBT

Switch

&

Bouncer

CAP

BANK

10 kV115 kVCharging

Supply

300kW

Klystron1300 MHz

TESLA MBKor 325MHz

JPARC

3 msecx 5 Hz

10kV

Reconfigure & add new modulators for 3, 2, or 1 msec beam pulse widths for upgrade scenarios

Pulse Transformer& Oil Tank

IGB

T Sw

itch

& B

ounc

er

CA

P B

AN

K

10 kV115 kVCharging

Supply

300kW

Klystron1300 MHz

TESLA MBKor 325MHz

JPARC

1.5 msecx 10 Hz

10kV

PULSED KLYSTRONS at SMTF(supported by these modulators…)

1. All TESLA 10 MW Multi-Beam Klystrons– Thales, Toshiba, & CPI

2. 325 MHz 3 MW Toshiba (JPARC) Klystron3. Existing 5 MW 1300 MHz Thales Klystrons

– Power will be limited to ~4MW by gun voltage

4. Basically any 115kV diode-mode Klystron

Initial configurations: 1) Thales 1300 MHz MBK, 1.5 msec x 10 Hz2) Toshiba/JPARC 325 MHz, 4.5 msec x 3 Hz

Initial SMTF Klystrons

Toshiba E3740A325 MHz 3 MW(In Production for JPARC )

Thales TH18011300 MHz10 MW

8 GeV SCRF LinacE (GeV) Technology Frequency1.3 – 8.0 GeV TESLA β = 1.00 1300 MHz

0.5 – 1.3 GeV Elliptical β = 0.8 1300 MHz

0 – 3 MeV Warm Copper RFQ 325 MHz

0.1 – 0.5 GeVElliptical β = 0.5, 0.6

- or -RIA Spokes β ~ 0.5

1300 MHz- or -

325 MHz10 – 100 MeV RIA Spokes β ~ 0.2 325 MHz

3 – 10 MeVRIA Spokes β ~ 0.1

- or -Warm Copper DTL

325 MHz

325 MHz Front-End Linac• Operates at ¼ of TESLA’s 1300 MHz • Extend Superconducting Linac to as low

an energy as possible• Single Klystron drives Front End Linac

– TESLA-style fan-out from one large Klystron to many Superconducting Cavities

• Requires development of Fast Ferrite Tuners for phase & amplitude control of individual cavites

M

325 MHz RF SystemMODULATOR: FNAL/TTF Reconfigurable for 1,2 or 3 msec beam pulse

Pulse Transformer& Oil Tank

IGBT Switch & Bouncer

CAP

BANK

10 kV110 kVCharging

Supply

300kW

SingleJPARC Klystron325MHz

3 MW

WR2300 Distribution Waveguide

TOS

HIB

A E

3740

A

I

Q

M

E

I

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M

B

I

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M

T

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I

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Cables toTunnel

D

I

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M

S

I

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M

R

I

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M

I

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MD

I

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M

S

I

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M

R

I

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M

10kV

S

I

Q

M

S

I

Q

M

R

I

Q

M

S

I

Q

M

S

I

Q

M

R

I

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M

400kW

Fast Ferrite Isolated I/Q Modulators

RF Couplers 120 kW20 kW20 kW

H-

Medium EnergyBeam TransportCopper Cavities

Radio FrequencyQuadrupole

Cryomodule #1 Single-SpokeResonators

Cryomodule #2 Double-Spoke

Resonators

325 MHzFront-EndLinac

325 MHz Klystron – Toshiba E3740A (JPARC)

115kV Pulse Transformer

ModulatorCapacitor / Switch / Bouncer

ChargingSupply

RFQ

MEBT

SCRF SpokeResonatorCryomodules

RFDistributionWaveguide

FerriteTuners

Single KlystronFeeds SCRF Linacto E > 100 MeV

Two Key Choices for 325 Linac

• Copper – to – SCRF transition

• Spokes – to – elliptical transition

• R&D Strategy: leave choice open as long

as possible

RF Fanout at Each Cavity

CIRCULATOR/ ISOLATOR

Magic Tee

FerriteLoaded Stub

CAVITYBEAM

DIRECTIONAL COUPLER

E-H TUNER

KLYSTRON

35 footwaveguidefrom galleryto tunnel

CIRCULATOR / ISOLATOR - Passes RF power forward towards cavity - Diverts reflected power to water cooled load

KLYSTRON - RF Power Source - Located in Gallery above tunnel - Each Klystron Feeds 8-16 Cavities

DIRECTIONAL COUPLER - Picks of a fixed amount of RF power at each station - Passes remaining power downstream to other cavities

E-H TUNER - Provides Phase and Amplitude Control for Cavities - Biased Ferrite Provides Electronic Control

SUPERCONDUCTING RF CAVITY - Couples RF Power to Beam

Fast Ferrite I/Q Modulator Concept

• Single Module Incorporating1. Circulator / Isolator

2. Hybrid

3. Two Fast-Ferrite Tuning Stubs

• Provides complete resonance control for individual cavity

• Low power versions fit on Single Circuit Board?

ELECTRONICALLY ADJUSTABLEE-H TUNER (1300 MHz Waveguide)

Magic Tee

MICROWAVE INPUT POWER from Klystron and Circulator

E-HTUNER

Reflected Power(absorbed by circulator)

ATTENUATED OUTPUT TO CAVITY

ELECTRONIC TUNINGWITH BIASED FERRITE

Bias Coil

FerriteLoadedStub

FERRITE LOADED SHORTED STUBSCHANGE ELECTRICAL LENGTH DEPENDING ON DC MAGNETIC BIAS.

TWO COILS PROVIDE INDEPENDENTPHASE AND AMPLITUDE CONTROL OF CAVITIES

Attractive Price Quote from AFT

(<< Klystron)

Advanced RF Distribution

DIRECTIONALCOUPLER

(POWER SPLIT)

MAGIC TEEAND CAVITY RF

POWER COUPLER

CIRCULATORAND LOADCOAXIAL

FERRITE STUBTUNER ANDWAVEGUIDETRANSITION

RF FROMKLYSTRON

E/

YET!

Ferrite Tuner

Contract Placedwith AFT for

full-spec I/Q tuner

In-house designtested to 660kW

325 MHz Branch-Line Hybrid

• At 325MHz and tens of kW, I/Q modulator

can be made on stripline circuit board

325 MHz Circulator

More Information on Ferrite Tuners

• Proton Driver RF Group Meeting Minuteshttp://tdserver1.fnal.gov/8gevlinacpapers/Meeting_Minutes/RF/Index.html

325 MHzFront-EndLinac

325 MHz Klystron – Toshiba E3740A (JPARC)

115kV Pulse Transformer

ModulatorCapacitor / Switch / Bouncer

ChargingSupply

RFQ

MEBT

SCRF SpokeResonatorCryomodules

RFDistributionWaveguide

FerriteTuners

Single KlystronFeeds SCRF Linacto E > 100 MeV