Tech. Specs. & Tolerances

Superconducting Undulator Research and Development: Technical Specifications

D. Arbelaez (LBNL), M. Barry (LBNL), P. Emma (SLAC), J. Fuerst (ANL/APS), E. Gluskin (ANL/APS), N. Holtkamp (SLAC), Y. Ivanyushenkov (ANL/APS), H.-D. Nuhn (SLAC), G. Pile (ANL/APS), S. Prestemon (LBNL), M. White (ANL/APS) April 5, 2014

Introduction

Two 1.5-m long prototype superconducting undulators will be developed using NbTi conductor at ANL/APS, and Nb3Sn at LBNL. The technical specifications for each design are described below in Table 1 and the detailed undulator tolerances and beam-heating estimates are listed in Table 2.

Table 1: Prototype planar undulator parameters.

Parameter Symbol NbT Nb3Sn Unit i

Undulator period u 21.0 19.0 mm

Magnetic full gap gm 8.0 8.0 mm

Vacuum chamber stay-clear (full internal height) gvc 5.7 5.7 mm

Prototype length Ls 1.50 1.50 m

Maximum K-value (peak) Kmax 3.27 3.31 -

Maximum vertical field (peak) Bmax 1.66 1.86 T Percentage of short sample limit of conductor - 80 80 %

Operating temperature of conductor T0 4.2 4.2 K

Total cryogenic power required (@ 4.2 K) P0 ? ? W

Operating current IL ? ? A Table 2: Prototype planar undulator tolerances.

Parameter Symbol NbTi Nb3Sn Unit FEL wavelength (4 GeV & 15 GeV linacs): - 5 25 keV 5 25 keV - keV keV

Tolerable phase shake over 1.5 m (rms) rms 5? 5? 5? 5? deg First field integral tolerance BdL 40 ? 40 ? T-m Second field integral tolerance BdL 50 ? 50 ? T-m2

Effective mean K K/K0) 0.02? 0.02? 0.02? 0.02? % Vertical alignment tolerance |y| ? 50? ? 50? m

Good field region over x = ±1 mm B/B0 ? ? ? ? %

Maximum RW-wakefield power load (dP/dz)R 0.26 << 0.26 << W/m

Maximum spontaneous power load* (dP/dz)SR 1.1 << 1.1 << W/m * Assumes all spontaneous power impinges on chamber and absorbed (extreme case).