STF Beta <1 Front End Linac nfrastructure and Plans GW Foster Sept 29, 2004
Beta <1 Test Area(s) 1. TESLA-compatible beta<1 SCRF linac 325 Hz Pulsed Spoke Resonators TESLA-like RF fan out from single Klystron Fast ferrite phase shifters demo with beam 2. Possible RA Production Test Area to be discussed in Ken s talk
Beta<1 Linac R&D Goals 1. Collaborative Development of a Family of TESLA-compatible beta<1 cryomodules 1300 Hz beta<1 and 325 Hz 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 LC as well
Proton Driver - 0.5 W with TESLA Frequencies & SCRF F.E. H - 325 Hz Klystrons 1.5 W RF odulator 325 Hz test area ulti-cavity Fanout at 10-20kW/cavity Phase & Amplitude Adjust via Fast Ferrite Tuners SSR SSR SSR DSR DSR DSR "Pulsed RA" SCRF Linac 325 Hz 0-120 ev 8 GeV 0.5 W LNAC 12 Klystrons (2 types) 11 odulators 20 W ea. 1 Warm Linac Load 54 Cryomodules ~550 Superconducting Cavities TESLA Klystrons 1300 Hz 10 W odulator 48 cavites/ Klystron 1300 Hz test area odulator 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 "Squeezed TESLA" Superconducting Linac 1300 Hz 0.087-1.2 GeV 2 Klystrons 96 cavites in 12 Cryomodules TESLA Klystrons 1300 Hz 10 W odulator 36 cavites/ Klystron odulator odulator odulator Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 "TESLA" LNAC 1300 Hz Beta=1 8 Klystrons 288 cavites in 36 Cryomodules odulator odulator odulator odulator LC Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1 Beta=1
Two Design Points for 8 GeV Linac nitial: 0.5 W Linac Beam Power 8.3 ma x 3 msec x 2.5 Hz x 8 GeV = 0.5 W Twelve Klystrons Required Ultimate: 2 W Linac Beam Power 25 ma x 1 msec x 10 Hz x 8 GeV = 2.0 W 36 Klystrons Required Either Option Supports: 1.5E14 x 0.7 Hz x 120 GeV = 2 W Beam Power from Fermilab ain njector
Proton Driver Linac - Technology Flow JHF (KEK) 325 Hz RF and Klystron H _ R F RA (ANL) APT (LANL) SCRF Spoke Cavities Linac Accel. Physics PULSED RA SCRF Spoke Cavity Linac SNS (JLAB) RA (SU) SNS Production Experience β < 1 Cavity Design SNS / RA Beta < 1 Elliptical Cavity Linac New FNAL Proton Source FNAL ANL / SNS Fast Ferrite Shifters TESLA COLLABORATON TESLA Elliptical Cavity SCRF Linac 1.3 GeV Pulsed odulators PROTON DRVER Cavities Cryogenics Klystrons Beta = 1 1300 Hz Linear Collider Test Facility Other Labs & Universities RF Distribution 8 GeV NU Beamline & nfrastructure Neutrino Super-beams ain njector @2 W FNAL Proton Plan Upgrades 8 GeV beams: P, n, ν, µ, e Technological & HEP Applications Beam Transport and Collimation Design BNL / SNS
JHF 325 Hz RF and Klystrons for TESLA-Compatible* Front End JHF 325 Hz RF uad * TESLA frequency = 1300 Hz = 4*325 Hz JHF 325 Hz 3 W Klystron
LANL (APT) ANL (RA)
odulators at STF Alternate designs under evaluation & design since January 04 Switch-mode (SNS type) ismatched PFN FNAL/TTF Bouncer * SELECTED (for cost) * Two odulators 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 odulators odulators can be reconfigured & parts re-used for RF power upgrade scenarios Klystron 1300 Hz TESLA BK or 325Hz JPARC 115 kv 10 kv Pulse Transformer & Oil Tank GBT Switch & Bouncer CAP BANK 10kV Charging Supply 300kW 4.5 msec x 2.5 Hz Klystron 1300 Hz TESLA BK or 325Hz JPARC Klystron 1300 Hz TESLA BK or 325Hz JPARC 115 kv 10 kv Pulse Transformer & Oil Tank 115 kv 10 kv Pulse Transformer & Oil Tank GBT Switch GBT Switch & Bouncer & Bouncer CAP BANK CAP BANK 10kV 10kV Charging Supply 300kW Charging Supply 300kW 1.5 msec x 10 Hz 3 msec x 5 Hz Reconfigure & add new modulators for 3, 2, or 1 msec beam pulse widths for upgrade scenarios
PULSED KLYSTRONS at STF (supported by these modulators ) 1. All TESLA 10 W ulti-beam Klystrons Thales, Toshiba, & CP 2. 325 Hz 3 W Toshiba (JPARC) Klystron 3. Existing 5 W 1300 Hz Thales Klystrons Power will be limited to ~4W by gun voltage 4. Basically any 115kV diode-mode Klystron nitial configurations: 1) Thales 1300 Hz BK, 1.5 msec x 10 Hz 2) Toshiba/JPARC 325 Hz, 4.5 msec x 3 Hz
nitial STF Klystrons Thales TH1801 1300 Hz 10 W Toshiba E3740A 325 Hz 3 W (n Production for JPARC )
8 GeV SCRF Linac E (GeV) Technology Frequency 1.3 8.0 GeV TESLA β = 1.00 1300 Hz 0.5 1.3 GeV Elliptical β = 0.8 1300 Hz Elliptical β = 0.5, 0.6 1300 Hz 0.1 0.5 GeV -or- -or- RA Spokes β ~ 0.5 325 Hz 10 100 ev RA Spokes β ~ 0.2 325 Hz RA Spokes β ~ 0.1 3 10 ev -or- 325 Hz Warm Copper DTL 0 3 ev Warm Copper RF 325 Hz
325 Hz Front-End Linac Operates at ¼ of TESLA s 1300 Hz 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
325 Hz RF System ODULATOR: FNAL/TTF Reconfigurable for 1,2 or 3 msec beam pulse Single JPARC Klystron 325Hz 3 W TOSHBA E3740A 110 kv 10 kv Pulse Transformer & Oil Tank GBT Switch & Bouncer CAP BANK 10kV Charging Supply 300kW WR2300 Distribution Waveguide RF Couplers 400kW 20 kw 20 kw 120 kw Fast Ferrite solated / odulators Cables to Tunnel H- R F E B T S S R S S R D S R D S R Radio Frequency uadrupole edium Energy Beam Transport Copper Cavities Cryomodule #1 Single-Spoke Resonators Cryomodule #2 Double-Spoke Resonators
325 Hz Front-End Single Klystron Feeds SCRF Linac to E > 100 ev Linac SCRF Spoke Resonator Cryomodules RF EBT RF Distribution Waveguide Ferrite Tuners 115kV Pulse Transformer Charging Supply odulator Capacitor / Switch / Bouncer 325 Hz Klystron Toshiba E3740A (JPARC)
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 KLYSTRON KLYSTRON - RF Power Source - Located in Gallery above tunnel - Each Klystron Feeds 8-16 Cavities 35 foot waveguide from gallery to tunnel DRECTONAL COUPLER DRECTONAL COUPLER - Picks of a fixed amount of RF power at each station - Passes remaining power downstream to other cavities CRCULATOR/ SOLATOR CRCULATOR / SOLATOR - Passes RF power forward towards cavity - Diverts reflected power to water cooled load E-H TUNER Ferrite Loaded Stub agic Tee E-H TUNER - Provides Phase and Amplitude Control for Cavities - Biased Ferrite Provides Electronic Control BEA CAVTY SUPERCONDUCTNG RF CAVTY - Couples RF Power to Beam
Fast Ferrite / odulator Concept Single odule ncorporating 1. Circulator / solator 2. Hybrid 3. Two Fast-Ferrite Tuning Stubs Provides complete resonance control for individual cavity Low power versions fit on Single Circuit Board?
ELECTRONCALLY ADJUSTABLE E-H TUNER (1300 Hz Waveguide) E-H TUNER ELECTRONC TUNNG WTH BASED FERRTE CROWAVE NPUT POWER from Klystron and Circulator Reflected Power (absorbed by circulator) ATTENUATED OUTPUT TO CAVTY Attractive Price uote from AFT (<< Klystron) Ferrite Loaded Stub Bias Coil agic Tee TWO COLS PROVDE NDEPENDENT PHASE AND APLTUDE CONTROL OF CAVTES FERRTE LOADED SHORTED STUBS CHANGE ELECTRCAL LENGTH DEPENDNG ON DC AGNETC BAS.
Advanced RF Distribution RF FRO KLYSTRON DRECTONAL COUPLER (POWER SPLT) COAXAL FERRTE STUB TUNER AND WAVEGUDE TRANSTON E/ YET! CRCULATOR AND LOAD AGC TEE AND CAVTY RF POWER COUPLER
Ferrite Tuner n-house design tested to 660kW Contract Placed with AFT for full-spec / tuner
325 Hz Branch-Line Hybrid At 325Hz and tens of kw, / modulator can be made on stripline circuit board
325 Hz Circulator
ore nformation on Ferrite Tuners Proton Driver RF Group eeting inutes http://tdserver1.fnal.gov/8gevlinacpapers/eeting_inutes/rf/ndex.html
325 Hz Front-End Single Klystron Feeds SCRF Linac to E > 100 ev Linac SCRF Spoke Resonator Cryomodules RF EBT RF Distribution Waveguide Ferrite Tuners 115kV Pulse Transformer Charging Supply odulator Capacitor / Switch / Bouncer 325 Hz Klystron Toshiba E3740A (JPARC)