Development of a NdFe-Steel Hybrid Wiggler for SSRL (Stanford Synchrotron Radiation Laboratory),
LAWRENCE LIVERMORE NATIONAL LAB CA
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A NdFe-steel hybrid configured permanent magnet wiggler is being developed for insertion in the SPEAR ring. Featuring 15 complete periods, a 12.9-cm magnetic period length, and a peak magnetic field range of 0.01-1.4 Tesla, the wiggler was designed to provide an intense radiation source on Beam Line VIII-W. A new permanent magnet material, neodymium iron NdFe, is being used in the magnetic structure instead of rare earth cobalt, REC, used previously in the 27-period wiggler now on Beam Line VI. NdFe advantages include a 16 higher coercive force 10.6-kOe vs. 9.0-kOe and lower cost. The wiggler design features a thin walled, rigid vacuum chamber with pole pockets on opposing surfaces allowing a 2.1-cm minimum magnetic gap with a 1.8-cm beam vertical aperture. At 3 GeV the wiggler at peak field is expected to radiate approximately two kilowatts in a 5 mrad horizontal fan with a 7.8 keV critical energy. Calculations are in progress to model the wiggler radiation spatial and spectral radiation emission.