BCD input from WG2

WG2 12/08/2005H. Hayano

Chris Adolphsen

Terry Garvey

Hitoshi Hayano

Summary of BCD input

WG2 R&D activities: EU: TTF(XFEL) US: SMTF,SLAC R&D Asia: STF --> will be summarized by regional directors

WG2: Main Linac

WG2: Main LinacModulatorKlystronCavity packageGradientCryomodule configurationRF distributionCryogenicsTunnel curvatureTunnel layout

By WG5

Revisited by BCD task force

Modulator

Modulator

Baseline

Alternatives

Bouncer-compensated pulse transformer modulator

Marx-style generator,

DTI (Direct switch),DC-to-DC converter

Klystron

Klystron

Baseline

Alternatives

10MW multi-beam klystron

10MW sheet beam klystron,5MW Inductive Output Tube,10MW 12 beam MBK

Cavity

WG5

Cryomodule configuration

Cryomodule configuration

Baseline10MW klystron drives 24 TESLA cavities. considering 7% WG loss and 11% overhead for 35MV/m operation

Cavities divided into three cryomodules,Quad package in every 4-th cryomodules, Cos(2)type Quad + corrector windings+BPM, supported from GRP at center post, <10µm bunch-to-bunch resolution BPMCavity spacing 283mm Contradiction with GG2-BCD!

Cryomodule configuration

Alternatives

12 cavities in one cryomodule,Cavity spacing 250mm~180mm,HOM readout,Quad-BPM in separate cryostat,Putting movers on center support post and cryomodule support,Reduce Quad aperture to ~35mm,1µm resolution BPM

RF distribution

RF distribution

Baseline

Alternatives

TESLA-TDR like distribution system, circulators and tuners(3-stub or E-H) in each cavity.

Elimination of circulators.

Cryogenicsystem

Cryogenic system

Baseline

Alternatives

TESLA-TDR like layout, except refrigerator spacing (but likely 5km).Maintenance length is half of the refrigerator spacing.

U-tube or turn around for more shorter maintenance length,

Tunnelcurvature

Tunnel curvature

Baseline

Alternatives

The linac will follow the curvature of the earth, unless site-specific reason dictates otherwise.

Laser-straight linac,Straight-line segments.

Tunnellayout

Tunnel layout

Baseline

Alternatives

RF sources to be located outside the beam tunnel, to be distributed along a second tunnel or surface gallery that run parallel or near by the beam tunnel.Three WR650 WG to each rf unit (one WG per cryomodule)

TESLA-TDR like layout.

Contradiction with RF distribution BCD!

BCD RF unit

BCD RF unit cartoon

Bouncer modulatorMulti-beam klystron Pulse transformer

LLRF & instrumentationRF waveguides

cryomodulesRF distribution

Rey.hori