11-12 December 2008
CERN
Europe/Zurich timezone

WG 2

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   Topical tasks for Working Group #2, rev 3.<o:p> </o:p>

Task description<o:p></o:p>

Introduction by …<o:p></o:p>

Treated in WG-Session #<o:p></o:p>

Cavity design<o:p></o:p>

Introduction<o:p></o:p>

Frank Gerigk<o:p></o:p>

1<o:p></o:p>

Make recommendation on geometrical beta based on beam dynamics issues, in view of the impact on power dissipation, max. gradient, and required instrumentation<o:p></o:p>

 

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Optimize cavity geometry w.r.t. peak fields, multipactor, robustness against Lorentz-force detuning, tunability, HOM spectra, cross-talk between cavities, …<o:p></o:p>

 

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HOM coupler<o:p></o:p>

Introduction<o:p></o:p>

Joachim Tuckmantel/Hans-Walter Glock<o:p></o:p>

1<o:p></o:p>

Acquire results on HOM impedances, beam instability studies, and interaction between cavities via HOM propagation<o:p></o:p>

 

<o:p> </o:p>

Define strategy on HOM coupler design, prototyping and testing<o:p></o:p>

 

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Design HOM coupler (antenna vs. beam tube absorber), and cooling layout<o:p></o:p>

 

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Perform multipactor studies<o:p></o:p>

 

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Identify manufacture and conditioning capacities<o:p></o:p>

 

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Identify required equipment for HOM coupler tests (do we need room temperature model cavity?)<o:p></o:p>

 

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Manufacturing of cavities<o:p></o:p>

Introduction<o:p></o:p>

NN<o:p></o:p>

2<o:p></o:p>

Identify potential Labs with manufacturing competence (in house or with industry)<o:p></o:p>

 

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Identify potential commercial manufacturers<o:p></o:p>

 

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Agree on manufacturing and processing sequence<o:p></o:p>

 

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Identify required equipment (e.g. field flatness, frequency tuning) and what equipment is missing<o:p></o:p>

 

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Processing of cavity to obtain design performance<o:p></o:p>

Introduction<o:p></o:p>

Sergio Calatroni<o:p></o:p>

2<o:p></o:p>

Define strategy to reach full performance (25 MV/m for b = 1 cavities) for a fully equipped prototype cryomodule<o:p></o:p>

 

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Identify required equipment (e.g. electro-polishing, HPWR) and what is missing<o:p></o:p>

 

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RF tests of individual cavities<o:p></o:p>

Introduction<o:p></o:p>

Pierre Maesen<o:p></o:p>

2<o:p></o:p>

Identify need of re-processing and re-testing, the equipment required and what is missing<o:p></o:p>

 

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Diagnosis<o:p></o:p>

Introduction<o:p></o:p>

NN<o:p></o:p>

2<o:p></o:p>

Define required equipment  (on-line: Temperature mapping and other diagnostics methods in super-fluid helium) and what is missing<o:p></o:p>

 

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Define required equipment (off-line: Optical inspection system) and what is missing<o:p></o:p>

 

<o:p> </o:p>

Assembly of and test of fully equipped cryomodule<o:p></o:p>

Introduction<o:p></o:p>

Pierre Maesen<o:p></o:p>

3<o:p></o:p>

Identify required equipment, monitoring devices and what is missing<o:p></o:p>

 

<o:p> </o:p>

Do we need to simulate the slope?<o:p></o:p>

 

<o:p> </o:p>

High power RF coupler<o:p></o:p>

Introduction<o:p></o:p>

Guillaume Devanz/ Eric Montesinos<o:p></o:p>

3<o:p></o:p>

Define the conceptual design, the layout of cooling (including thermal loads) and diagnostical tools, choice of materials (waveguide, window)<o:p></o:p>

 

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Perform multipactor studies, assess methods of multipactor suppression and elaborate coating techniques<o:p></o:p>

 

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Measure secondary emission coefficient (SEC) of materials involved<o:p></o:p>

 

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Identify manufacture and conditioning facilities<o:p></o:p>

 

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Identify required equipment for coating and conditioning<o:p></o:p>

 

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Frequency tuner<o:p></o:p>

Introduction<o:p></o:p>

Guillaume Devanz<o:p></o:p>

3<o:p></o:p>

Perform by computer simulation Lorentz-force detuning studies of cavity design and confirm by measurement<o:p></o:p>

 

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Develop and test slow tuner; integrate the design into that of the cryomodule<o:p></o:p>

 

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Develop and test fast tuner; integrate the design into that of the cryomodule<o:p></o:p>

 

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Develop scenarios for failing cavities (detuning)<o:p></o:p>

 

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Magnetic shielding<o:p></o:p>

Introduction<o:p></o:p>

NN<o:p></o:p>

3<o:p></o:p>

Design by computer simulation or analytically the magnetic shielding; manufacture it<o:p></o:p>

 

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