Some Uses Of Repmms In Storage-Rings And Colliders

Improvements for existing rings and techniques for building new rings composed entirely of passive, Rare Earth Permanent Magnet Multipoles (REPMM's) are considered using circular dipoles, quadrupoles and sextupoles. Over the past few years we have made such magnets using a single size SmCos block with up to five easy-axis orientations. The final production scheme is modular in that magnets are built-up from quantized layers. All multipole layers are made in exactly the same way using algorithms differing only by the desired multipole sym- metry. The method is simple, efficient and inexpensive and allows a "deit-yourself" approach to constructing new mag- netic elements. For rings these might include focusing opti- cal klystrons, rotatable multipoles for diagnostics, correction or extraction, or possibly combined function systems for the unit cells. A high quality, low-beta, PMQ insertion which can change beta, tune and energy is described as well as the PMS's for the SD and SF elements of the' North SLC damping ,ring. Because these sextupoles will be the first optical use of PM's in storage rings they are discussed in detail together with the advantages, problems and requirements of such applications.