Völker, J.; Dürr, V.; Goslawski, P.; Jankowiak, A.; Titze, M.: Variable Permanent Hybrid Magnets for the Bessy III Storage Ring. In: Frank Zimmermann ... [Ed.] : IPAC2022 : Proceedings of the 13th International Particle Accelerator Conference, in Bangkok, Thailand, 12–17 June 2022Geneva: JACoW, 2022. - ISBN 978-3-95450-227-1, p. THPOTK001/1-4
https://accelconf.web.cern.ch/ipac2022/papers/thpotk001.pdf
Open Access Version
Abstract:
The Helmholtz Zentrum Berlin (HZB) is working on the conceptual design of a successor source to BESSY II, an new BESSY III facility, designed for a beam energy of 2.5GeV and based on a multi-bend achromat (MBA) lattice for a low emittances of 100pm-rad. Bending and focusing magnets in the MBA cells should consist of permanent magnets (PM), to allow for a competitive and compact lattice, to increase the magnetic stability and to decrease the electric power consumption of the machine. However, using pure permanent magnet systems would result in a completely fixed lattice. Therefore, we are developing Variable Permanent Hybrid Magnets (VPHM), combining PM materials like NdFeB with a surrounding soft iron yoke and additional electric coils. This design can achieve the same field strength and field quality as conservative magnets, with only a small fraction of the electric power consumption, and a ca. 10% variability in the field amplitudes. In this paper, design and first optimization results of the magnets will be presented, which are a promising option for the new BESSY III facility, and an estimated reduction in total power consumption for the magnet lattice of up to 80%.