ILC Positron Work: SLAC and LLNL

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ILC Positron Work SLAC and LLNL J. C.
Sheppard, et al., SLAC J. Gronberg, et al.,
LLNL April 7, 2005
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SLAC and LLNL Effort Design
studies towards viable Conventional and Undulator
Based Positron System Designs for the ILC Goal is
to have a draft design document for distribution
at Snowmass. Description of both systems for use
in making choice for the ILC Baseline
Design Upcoming meeting at Daresbury Laboratory,
UK April 10-13 to understand and coordinate
global activities expression of interest
perhaps letters of intent E166 Demonstration
of Undulator Based Polarized Positron
Production BNL Target Material Radiation Damage
Tests KEK Target Material Energy Deposition
Damage Threshold Studies
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SLAC LLNL UCB BNL Cornell (U) Daresbury
(U) DESY Z(?) (U) KEK
Positron Injection (from D.C. Schultz)
A generic positron source. How many are needed?
e-
e-, ?
L-band NC capture section
e
target
Solenoid, 0.5T ?
SC pre-accelerator
Solenoid, 1T
flux concentrator 5T
A lot of effort to-date has been undulator based
(TESLA, USLCTOC). Conventional source feasibility
is an important topic.
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Parameters/Specifications
Bunch trains at 5hz 2820 bunches per train,
upgradeable to 4886 (?) 337 ns bunch spacing in
and out of the DRs 2x1010 e per bunch out of
the DRs Polarization (perhaps) 60
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Topics for Study
Basic Capture Yield Calculations (AMD, rf
gradient, focusing optics, capture
aperture(6-D)) Energy Deposition and
Stress Radiation Damage Threshold Candidate
Target Material Selection and Testing Average
Power Removal Target Station Layout Removal and
Replacement Scenarios Infrastructure (remote
handling, equipment shielding) Undulator
Insertion Bandpass and Machine Protection Civil
Facility Specifications Commissioning,
Operations, Availability
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Activities for a CDR
Specification of Beam Parameters Specification of
Damping Ring 6-D Acceptance (looking into
requirement for a predamping ring for increased
acceptance and relaxation of e production
systems) Decision on Baseline Design Option
Conventional Undulator, other (is the Compton
Backscattered Photon System Adaptable to the SC
Design Parameters?) Design Parameter Choice
Optimization Resolution of Availability
Issues Fall Back Scenarios Upgrade Options
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Activities for a TDR
AMD Prototype Demonstration Capture rf Section
Prototype (incl. rf power source if
required) Material Damage and Shielding
Tests Target Station Prototype Undulator
Section Prototype Photon Collimator Design and
Test as Needed
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Possible US Collaborators
SLAC ILC, SLAC RP LLNL/UCB/BNL LLNL ANL (Univ.
Chicago?) ORNL Cornell Princeton Plus anyone else
with interest, capability, support