| Paper | Title | Page |
|---|---|---|
| MOPLT112 | Optimizing Non-Scaling FFAG Lattices for Rapid Acceleration | 800 |
|
||
|
A linear approach to fixed field acceleration was first proposed [*,**] and successfully developed to support the rapid and large-emittance acceleration of muons for a Neutrino Factory or Muon Collider. Lattices have evolved from a simple F0D0-cell base as first proposed to a slightly more complex layout that has been referred to as a triplet configuration. In this work a methodology is developed for optimizing nonscaling lattices which demonstrates that the appropriate description is minimum momentum compaction, alpha=(dL/L)/(dp/p). Further, the triplet configuration is not used conventionally as a focusing telescope, but rather its optics is shown to resemble that of a F0D0-cell. This methodology is then used to propose and compare lattices for muon acceleration. Specifically a 2.5-5, 5-10, and 10-20 GeV/c lattice is proposed for muon acceleration and also one for a small, 10-20 MeV/c electron prototype machine.
* C. Johnstone, "FFAG Non-scaling Lattice Design", talk, Proc 4th Int Conf on the Physics Potential and Development of the m+ m- Colliders, San Francisco, CA Dec.10-12, 1997, pgs 696-698** F. Mills, "Linear Orbit Recirculators", ibid, pgs 693-696 |
||
| TUPLT006 | Simple Analytic Formulae for the Properties of Nonscaling FFAG Lattices | 1138 |
|
||
| A hallmark of the "non-scaling" FFAG lattices recently proposed for neutrino factories and muon colliders is that a wide range of momentum is compacted into a narrow radial band; dL/L is of order 10-3 for dp/p of order unity. This property is associated with the use of F0D0 or FDF triplet lattices in which the F magnet provides a reverse bend. In this paper simple analytic formulae for key lattice properties, such as orbit displacement and path length as a function of momentum, are derived from thin-element models. These confirm the parabolic dependence of path-length on momentum observed with standard orbit codes, reveal the factors which should be adjusted to minimize its variation, and form a useful starting point for the thick-element design (for which analytic formulae are also presented). A key result is that optimized doublet, F0D0 and triplet cells of equal length and phase advance have equal path-length performance. Finally, in the context of a 10-20 GeV/c muon ring, the thin-element formulae are compared against lattice optical properties computed for thick-element systems; the discrepancies are small overall, and most discernible for the triplet lattices. | ||
| TUPLT179 | Mini-bunched and Micro-bunched Slow Extracted Beams from the AGS | 1544 |
|
||
| BNL's AGS has a long history of providing slow extracted proton beams to fixed target experiments. This program of providing high quality high intensity beams continues with two new experiments currently being designed for operation at the AGS; both of these new experiments require slow extracted beam, but with an added requirement of those beams experiments require slow extracted beam, but with an added requirement of those beams experiments and initial tests have been performed. In this report we will describe the beam requirements for the two experiments, and present results of detailed simulations and initial beam tests. | ||
| THPLT006 | A Comparison of COSY DA Maps with Analytic Formulae for Orbit Functions of a Non-scaling FFAG Accelerator | 2466 |
|
||
| Fixed Field Alternating Gradient (FFAG) magnetic lattices with fixed, possibly high, radio-frequency proposed for muon acceleration have unusual requirements: relative momentum swing dp/p of ± 30% and relative spread of revolution frequencies < 10-3. It is not evident whether the existing accelerator optical design codes are sufficiently accurate for such a large momentum range. Analytic expressions for orbit displacements, tunes and path length have been derived for thick-element models of doublet, F0D0 and FDF triplet lattices; it is this paper's purpose to compare these with values computed by SYNCH and COSY, and truncated Taylor maps constructed by Lie algebra. The mutual agreement of results from independent sources will serve to validate them all. A mathematical necessity is that one at least of the magnets be of the combined-function type, and with entrance and exit faces disposed in a sector layout. It is sufficient to consider the triplet case because in the limit that the two F quadrupoles are combined, the cell reduces to the simpler F0D0. We use as our example a "nonscaling" FFAG ring proposed for accelerations of muons over the momentum range 10-20 GeV/c. |