Cornell University Unit Name

ILC Damping Ring Wiggler Development

• Notes from
• Summary of

Physics Optimization

Jeremy Urban has been working on ILC Damping Rings R&D Objective 3.4.6.A: Develop physics design for damping wigglers. A version of the superferric CESR-c wiggler was modified for use in ILC damping ring stutides, as documented in a PAC05 paper titled CESR-c Wiggler Studies in the Context of the International Linear Collider Damping Rings. Ultimately, a Superferric ILC-Optimized CESR-c (SIOC) wiggler was derived with the following design and performance parameters that met the ILCDR physics and engineering requirements.

Magnet Parameter	Value
Peak Field	1.95 T
Number of poles	12
Total length	1.68 m
Period	32 cm
Pole width	23.8 cm
Gap height	8.6 cm
DB/Bmax at x=10mm	0.06 %
Coil current	141 A

Lattice Parameter in OCS v2	Value
Damping time	26.4 ms
Radiation equilibrium horizontal emittance	0.56 nmrad
Radiation equilibirum energy spread	0.13 %
Dynamic aperture	8 x injected beam size
Off-energy dynamic aperture	7-8 x injected beam size
Dynamic aperture w/ multipole errors on D/Q/S magnets	5 x injected beam size

Initial results for this work are documented in an EPAC06 paper titled Optimiziation of CESR-c Superferric Wiggler for the ILC Damping Rings. Final results for this work are documented in Jeremy's dissertation titled An Optimized Superferric Wiggler Design for the International Linear Collider Damping Rings. Included in this webpage is a summary of the recommendations and conclusions, as well as files investigators can download to use the SIOC wiggler model on their own--these files are also given here:

Radia file (Mathematica notebook)

Magnetic field table (Radia output)

Magnetic field fit (Cornell fit procedure)

Taylor map for tracking (Bmad output)