Title :
Corrections to the Fermilab recycler focusing with end shim changes
Author :
Johnson, D.E. ; Brown, B.C. ; Foster, G.W. ; Gattuso, C. ; Jackson, G.P. ; Mishra, C.S. ; Pruss, S.M. ; Volk, J.T. ; Yang, M.J.
Author_Institution :
Fermi Nat. Accel. Lab., Batavia, IL, USA
Abstract :
The Recycler Ring Gradient Magnets were designed with end shims which correct the field shape (harmonic components up to 10-pole). A standard correction was employed at one end to correct the average properties. A variable correction was used at the other end to correct individual magnet variations during the fabrication process. An initial Recycler operation revealed that the quadrupole fields did not produce the desired tune. In part, this was due to the sextupole of the end-shim interacting with the curved orbit through the straight magnet. The standard end-shim was replaced on all regular cell gradient magnets. Details of these end corrections and the resulting successful modification of the lattice are described
Keywords :
accelerator cavities; accelerator magnets; beam handling equipment; particle beam focusing; permanent magnets; proton accelerators; proton beams; storage rings; synchrotrons; FODO lattice; Fermilab recycler focusing corrections; Recycler Ring gradient magnets; Recycler antiproton storage ring; Recycler operation; beam measurements; chromaticity; end shim changes; fabrication process; field shape corrections; harmonic components; lattice modification; magnet variations; permanent magnet gradient dipoles; permanent magnet quadrupoles; quadrupole fields; sextupole; straight magnet; tune; variable correction; Apertures; Electromagnetic coupling; Electromagnetic measurements; Extraterrestrial measurements; Lattices; Magnetic analysis; Magnetic field measurement; Magnetic materials; Permanent magnets; Shape control;
Conference_Titel :
Particle Accelerator Conference, 2001. PAC 2001. Proceedings of the 2001
Conference_Location :
Chicago, IL
Print_ISBN :
0-7803-7191-7
DOI :
10.1109/PAC.2001.987836
