198,500 research outputs found
Low-emittance storage rings
The effects of synchrotron radiation on particle motion in storage rings are
discussed. In the absence of radiation, particle motion is symplectic, and the
beam emittances are conserved. The inclusion of radiation effects in a
classical approximation leads to emittance damping: expressions for the damping
times are derived. Then, it is shown that quantum radiation effects lead to
excitation of the beam emittances. General expressions for the equilibrium
longitudinal and horizontal (natural) emittances are derived. The impact of
lattice design on the natural emittance is discussed, with particular attention
to the special cases of FODO, achromat, and TME style lattices. Finally, the
effects of betatron coupling and vertical dispersion (generated by magnet
alignment and lattice tuning errors) on the vertical emittance are considered.Comment: Presented at the CERN Accelerator School CAS 2013: Advanced
Accelerator Physics Course, Trondheim, Norway, 18-29 August 201
Questions of Identity
As an introduction to NuFact '99, the ICFA/ECFA Workshop on Neutrino
Factories Based on Muon Storage Rings, I place the issues of neutrino
properties and neutrino oscillations in the broader context of fermion flavor.Comment: Introduction to NuFact '99, the ICFA/ECFA Workshop on Neutrino
Factories Based on Muon Storage Rings. 15 pages; LaTeX, uses elsar
Spin Oscillations in Storage Rings
The dependence of the particle rotation frequency on the particle orbit
perturbations is found. The exact equation of spin motion in the cylindrical
coordinate system is derived. The calculated formula for the frequency of g-2
precession is in the best agreement with previous results. Nevertheless, this
formula contains the additional oscillatory term that can be used for fitting.
The influence of spin oscillations on the spin dynamics in the EDM experiment
is negligible.Comment: 5 pages. To appear in the proceedings of 16th International Spin
Physics Symposium (SPIN 2004), Trieste, Italy, 10-16 Oct 200
An improved empirical equation for bunch lengthening in electron storage rings
In this paper we propose an improved empirical equation for the bunch
lengthening in electron storage rings. The comparisons are made between the
analytical and experimental results, and the agreements are quite well. This
improved equation can be equally applied to the case where a storage ring is
very resistive (such as the improved SLC damping rings) instead of inductive as
usual.Comment: 9 page
Nuclear Astrophysics in Storage Rings
Nuclear reaction cross sections are usually very small in typical
astrophysical environments. It has been one of the major challenges of
experimental nuclear astrophysics to assess the magnitude of these cross
sections in the laboratory. For a successful experiment high luminosity beams
are needed. Increasing the target width, one also increases the reaction
yields. But, this is of limited use due to multiple scattering in the target.
Storage rings are a very good way to overcome these difficulties. In principle,
they can be tuned to large luminosities, and have the advantage of crossing the
interaction region many times per second (typically one million/s),
compensating low density internal gas targets, or low reaction rates in
beam-beam collisions. Storage rings are also ideal tools for precise
measurements of masses and beta-decay lifetimes of nuclei of relevance for
astrophysics.Comment: 14 pages, LaTeX, figures available upon reques
Conceptual design of elliptical cavities for intensity and position sensitive beam measurements in storage rings
Position sensitive beam monitors are indispensable for the beam diagnostics
in storage rings. Apart from their applications in the measurements of beam
parameters, they can be used in non-destructive in-ring decay studies of
radioactive ion beams as well as enhancing precision in the isochronous mass
measurement technique. In this work, we introduce a novel approach based on
cavities with elliptical cross-section, in order to compensate for existing
limitations in ion storage rings. The design is aimed primarily for future
heavy ion storage rings of the FAIR project. The conceptual design is discussed
together with simulation results.Comment: Added definition of Uv and Pdiss in the introduction section. Added
Mode numbering in table 1 and figure 1 for more clarity. Corrected one wrong
figure reference. Other minor typo correction
Online optimization of storage ring nonlinear beam dynamics
We propose to optimize the nonlinear beam dynamics of existing and future
storage rings with direct online optimization techniques. This approach may
have crucial importance for the implementation of diffraction limited storage
rings. In this paper considerations and algorithms for the online optimization
approach are discussed. We have applied this approach to experimentally improve
the dynamic aperture of the SPEAR3 storage ring with the robust conjugate
direction search method and the particle swarm optimization method. The dynamic
aperture was improved by more than 5 mm within a short period of time.
Experimental setup and results are presented
Nonequilibrium electron rings for synchrotron radiation production
Electron storage rings used for the production of synchrotron radiation (SR)
have an output photon brightness that is limited by the equilibrium beam
emittance. By using interleaved injection and ejection of bunches from a source
with repetition rate greater than 1 kHz, we show that it is practicable to
overcome this limit in rings of energy ~1 GeV. Sufficiently short kicker pulse
lengths enable effective currents of many milliamperes, which can deliver a
significant flux of diffraction-limited soft X-ray photons. Thus, either
existing SR facilities may be adapted for non-equilibrium operation, or the
technique applied to construct SR rings smaller than their storage ring
equivalent.Comment: 5 pages, 2 figures; accepted for publication in Physical Review
Letter
The Potential for Neutrino Physics at Muon Colliders and Dedicated High Current Muon Storage Rings
Conceptual design studies are underway for muon colliders and other
high-current muon storage rings that have the potential to become the first
true ``neutrino factories''. Muon decays in long straight sections of the
storage rings would produce precisely characterized beams of electron and muon
type neutrinos of unprecedented intensity. This article reviews the prospects
for these facilities to greatly extend our capabilities for neutrino
experiments, largely emphasizing the physics of neutrino interactions.Comment: 107 pages, 16 figures, to be published in Physics Report
- …