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ILC e+ Source

Annual DoE SLAC HEP Program Review

Y. Batygin, V. Bharadwaj, R. Miller, Y. Nosochkov, J. Sheppard, J. Wang, and M. Woodley; SLAC

J. Gronberg, T. Piggot, W. Stein, S. Walston; LLNL

J. C. Sheppard, SLAC

June 7, 2006

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ILC Baseline e+ Source Parameters

Note: The SLC e+ source beam power was ~1 kW vs. ~350 kW for ILC

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Layout of ILC Positron Source(BCD: Snowmass Frascati, 2005)

e- sourcee-

DR

e- Dump Photon Dump

e+

DRAuxiliary e- Source

Photon Collimators

Adiabatic Matching

Device

e+ pre-accelerator ~5GeV

150 GeV 100 GeV

HelicalUndulatorIn By-Pass

Line

PhotonTarget

250 GeV

Positron Linac

IP

Beam Delivery System

e- Target

Adiabatic Matching

Device

e- Dump

Photon production at 150 GeV electron energyK=1, =1 cm, 200 m long helical undulatorTwo e+ production stations including a back up.Keep alive auxiliary source is e+ side.

M. Kuriki, KEK

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Note: The web site is under continuous development

( http://www-project.slac.stanford.edu/ilc/acceldev/eplus/ )

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• E166: Demonstration experiment

• Eddy Current Studies

• Target Layout

• Optics development

• Undulator discussions

• NC RF

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Positron yield at 5 GeV (e+/e+target) for undulator based source with E/E 1% for immersed target with Bz= 6T and for shielded target.

Positron System Optics: Capture

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AMD ( Flux Concentrator)

Value Bz, Tesla

00.5

11.5

22.5

33.5

44.5

55.5

66.5

77.5

88.5

99.510

10.511

-1 -0.75 -0.5 -0.25 0 0.25 0.5 0.75 1 1.25 1.5

Z, m

Bz,

Tes

la

Pulsed AMDDC AMD

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Cu Disk

NdFeB Magnet

Strain Gauges

Eddy Current Studies

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Tangential Force vs. RPM

0

0.5

1

1.5

2

2.5

0 200 400 600 800 1000 1200 1400 1600 1800 2000

RPM

Tan

gen

tial Forc

e (

pou

nd

s)

Cu, z=0.01 in

Cu, z=0.05 in

Cu, z=0.1 in

Al, z=0.01 in

Al, z=0.05 in

Al, z=0.1 in

Ta

ng

en

tia

l F

orc

e (

Arb

. U

nit

s)

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Pulsed Flux Concentrator, circa 1965: Brechna et al.

(D. Mayhall, W. Stein, T. Piggot, J. Gronberg, LLNL study)

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A conceptual design for the positron target Eddy currents in a spinning metal disc

Positron Target and AMD (SLAC, LLNL, Liverpool Univ., Daresbury, Cockcroft)

[Pulsed Flux Concentrator for RDR]

100 m/s

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Positron Target and AMD (LLNL)

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Positron System Optics Design~ 18 km of Beam Lines incl. ~2300 magnets

125 MeV-5 GeV LTR Optics Deck

Parts Count Done

Functionality, Operability, Optimization Studies Continuing

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Undulator DevelopmentSLAC, ANL, LBNL, Daresbury

K=1, =1 cm, ID> 4 mm, helical, SC e+ Undulator

What can be done?

What needs to be demonstrated?

Most importantly, how will we work together?

Are formal protocols necessary?

What next?

NOTE: Lund (150/E[GeV] )4x (cm)2 xK-4/3

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• Goal: Evaluate performance of a 1.3 GHz,

NC cavity

• Issues: Significant heating from both rf and particle losses,

must sustain high surface fields (~ 35 MV/m for 1 msec)

Normal Conducting RF Structure Development: SW and TW required for e+ and e- Capture

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SLAC ILC e+ BCD/RDR Summary

All (?) pieces identified

High Level Parts List Complete

Ongoing R&D:

Undulator

Target

AMDs

NC RF

(Remote handling, not started)

Goals

RDR and Cost Estimate, end of calendar 2006

TDR w/ key technology demos, end of calendar 2009