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CLIC_DDS study 30.11.2010

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CLIC_DDS Study Collaboration

• Vasim Khan

• Alessandro D’Elia

• Roger Jones

• Alexej Grudiev

• Germana Riddone

• Vadim Soldatov

• Walter Wuensch

• Riccardo Zennaro

University of Manchester and Cockcroft institute, U.K.

CERN, Switzerland

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192 cells8-fold interleaving

24 cellsNo interleaving

192 cells8-fold interleaving

Manifold

Coupling slot

Dipole mode Manifold mode

∆fmin = 65 MHz∆tmax =15.38 ns∆s = 4.61 m

∆fmin = 8.12 MHz∆tmax =123 ns∆s = 36.92 m

∆f=3.6 σ =2.3 GHz∆f/fc=13.75%

Summary of CLIC_DDS_C

Meets design Criterion?

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Surface fields

Fail to satisfy rf breakdown constraints!

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CLIC_DDS optimisation: H-fieldCircular

Circular cell

ε=0.82

ε=1.38

Manifold-damped single cell

ε=1.38

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CLIC_DDS optimisation: E-field

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Surface fields

DDS_E

DDS_C

DDS_E

DDS_C

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CLIC_DDS_A: Monopole properties

Max. Values

Esur=220 MV/m∆T = 51 KPin= 70.8Eacc_UL=131 MV/mSc=6.75 W/μm2

RF-beam-eff=23.5%

∆T

35*Sc

Esur

Eacc

Pin

Dashed curves : Unloaded conditionSolid curves: Beam loaded condition

CLIC_G Values

Esur=240 MV/m∆T = 51 deg.Pin= 63.8Eacc_UL=128 MV/mSc=5.4 W/μm2

RF-beam-eff=27.7%

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CLIC_DDS_A: Dipole properties24 cellsNo interleaving

Qavg ~1700

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CLIC_DDS_A: 24+2 cells

198.6326mm

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Water pipes for cooling Vacuum flange

Vacuum flangePower input

Power outputTuning holes

Cut-view

Beam

Thanks to Vadim Soldatov

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Profileaccuracy

VDL

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Acknowledgments

• We have benefited from discussions with Juwen Wang, Zhengai Li and Toshiyasu Higo on X-band structures

Thank you

Closing remarks

• CLIC_DDS_A is being fabricated

• CLIC_DDS_A: High power test by 2011 end

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Additional slides