Ian Bailey

University of Liverpool / Cockcroft Institute

UK Target Update

EUROTeV: WP4 (polarised positron source) PTCD task

I. Bailey, J. Dainton, L. Jenner, L. Zang (Cockcroft Institute / University of Liverpool)

D. Clarke, K. Davies, A. Gallagher, N. Krumpa (CCLRC Daresbury Laboratory)

C. Densham, M. Woodward, B. Smith (CCLRC Rutherford Appleton Laboratory)

J.L. Fernandez-Hernando, D.J. Scott (CCLRC ASTeC Daresbury Laboratory / Cockcroft Institute)

P. Cooke, P. Sutcliffe (University of Liverpool)

In collaboration with

Jeff Gronberg, David Mayhall, Tom Piggott, Werner Stein (LLNL)

Vinod Bharadwaj, John Sheppard (SLAC)

UK Target R&D Involvement

• Target simulations (with DESY)– Detailed geometry for FLUKA (presented in target hall session)– Planned GEANT4 spin transport simulations– Eddy current simulations (Jim Rochford - this session)

• Photon Collimator simulations– Beginning FLUKA simulations – (Lei Zang, University of Liverpool)

• Target wheel prototyping (this talk)– Proposed 3 staged prototypes sited at DL – Pending funding

• Remote-handling solutions– RAL (presented in target hall session)

• Alternative target materials– Alternative metals, ceramics (alumina + zirconia), etc– RAL (work underway)

Proposed Timeline (100% funding scenario)Stage 1

• Construct and test a prototype to establish the mechanical stability of the target wheel assembly in the field of a strong magnet. Does not include internal water-cooling channels. Does not include vacuum vessel or vacuum conditions.– Apr 07 - Design of first target prototype wheel complete.– May 07 - Infrastructure in place at Daresbury Laboratory.– Jun 07 - Design of target test rig and instrumentation complete.– Aug 07 - Construction of target test rig complete.– Aug 07 -Construction of first prototype complete.– Nov 07 - Initial testing of first prototype complete.– Feb 08 – All testing of first prototype complete. – Mar 08 - Data from first prototype fully analysed.

Proposed Timeline (100% funding scenario)Stage 2

• Construct and test a prototype to demonstrate operation of the target assembly when cooling system is operated in vacuum conditions. Testing both with and without magnet depending on conclusions of stage 1.– Nov 07 – Design of second target prototype wheel complete.– Jan 08 - Design of upgraded target test rig and instrumentation

complete.– Apr 08 - Construction of second prototype complete.– Apr 08 - Upgrade of target test rig complete.– Jul 08 - Initial testing of second prototype complete.– Oct 08 - All testing of second prototype complete. – Dec 08 - Data from second prototype fully analysed

Proposed Timeline (100% funding scenario)Stage 3

• Construct and test a prototype to establish performance of the target cooling system with heat load. Using latest target design and latest capture optics design if appropriate / available.– Mar 08 - Identify possible technologies for simulating thermal load.– Aug 08 - Design of thermal load source and interface to test rig

complete.– Nov 08 – Design of upgraded target test rig and instrumentation

complete.– Nov 08 – Design of third target prototype wheel complete (if needed

following stage 2).– Feb 09 - Upgrade of target test rig complete.– Mar 09 - Installation of thermal load in test rig complete.– Mar 09 - Construction of third prototype complete.– Jun 09 – Initial testing of third prototype complete.– Oct 09 – Final testing of third prototype complete.– Feb 10 – Data from third prototype fully analysed.

We don’t expect 100% funding!

Stage 1 Prototype Target Wheel

Sectional view•1m diameter wheel with simplified structure compared to current baseline target wheel.

•Optional cantilever drive shaft (deflection measurements)

•Consistent with water-cooling (to be confirmed by LLNL)

•Uses Rigaku ferrofluidic feedthrough and is consistent with Deublin water union.

•Motor being sized for rotation up to 2000rpm.

Stage 1 Prototype Target Wheel (Hub Detail)

•Detail showing drive shaft and wheel hub.

•Reducing drive shaft to 2” diameter allows use of standard feedthrough and water coupling at 2000 rpm.

Stage 1 Prototype Target Wheel and Test Magnet

Sectional view

Test Magnet• Default option is to use magnet already based at DL

– GMW dipole electromagnet, model 3474-140– Normally used for Hall probe calibration

• Possibility of s/c magnet from BINP?

•1800 kg

•water-cooled

•adjustable pole gaps

Future PTCD ActivitiesTarget Prototyping

• Proposing 3 staged prototypes over 3 years (LC-ABD funding bid)

• Measure eddy current effects• top priority• major impact on design

• Test reliability of drive mechanism and vacuum seals.

• Test reliability of water-cooling system for required thermal load

• Develop engineering techniques for manufacture of water-cooling channels.

• Develop techniques for balancing wheel.

• First prototype mechanical deisgn progressing well.

• First prototype instrumentation and electronics design starting.

Remote-handling design • Essential that remote-handling

design evolves in parallel with target design.

• Determines target hall layout and cost.

• Evaluaitng change-over times.

Photon Collimator design• Use realistic photon beam.• Activation simulations (in

collaboration with DESY).• Thermal studies and cooling

design.• Variable aperture (optimise in

association with beam jitter simulations)?