Abstracts Brochure - CERN

WEPCH — Poster Session 28-Jun-06 16:00 - 18:00
magnet. It brings additional difficulties on design of an injection channel. In the paper the layout, results of design
and calculations of NESTOR injector channel are presented. The channel consists of two bending magnets, fivelens,
asymmetrical, objective and two-lens matching cell to compensate dispersion and focusing effects of a dipole
magnet fringe field and injection system elements (inflector). Presented results shows that designed lattice provides
matching of injected beam parameters with the storage ring acceptance, is stable to element alignment errors and is
easy controlled. The final values of the channel lens gradients can be defined only after measurements of inflector
field profile.
Peculiarities of Influence of Coherency Processes at Charged Particles Channeling on Particle
Beams Characteristics
In the work the length of reciprocal coherency
existence and peculiarities of coherency
of different states of channeled particles
wave functions are discussed. It was
V.I. Vysotskii, M.V. Vysotskyy (National Taras Shevchenko University
of Kyiv, Radiophysical Faculty)
shown that the length of coherent channeling depends on the monochromaticity of initial particle beam as well as
on the interaction of channeled particles with thermal oscillations of the crystal lattice. Peculiarities of influence of
coherency processes at relativistic and nonrelativistic charged particles channeling on spatial and angular characteristics
of particle beam that has passed through a thin crystal are discussed. In was shown, that the influence of
different particle states interference within the area of coherent channeling leads to very strong periodic dependence
of final beam angular width from the crystal length. This effect allows to control beam parameters (e.g., to form
narrower beam, that it was before falling on the crystal). Influence of coherency of particle states in a single channel
and several channels on the angular distribution and the possibility of quasicharacteristic short-wave spontaneous
and stimulated radiation is also studied.
Matrix Formalism for Current-independent Optics Design
Matrix formalism has been a powerful tool
for beam optics designs. It not only facili- C.-x. Wang (ANL)
tates computations but also plays an important
role in formulating various design concepts. Here we extend the standard matrix formalism for the purpose
of designing optics that transports space-charge dominated beam. Furthermore, we explore the concept of currentindependent
optics, which can be useful for systems such as high-brightness injectors and space-charge dominated
rings.
A New Algorithm for the Correction of the Linear Coupling at TEVATRON
The Fourier analysis of TBT data provides
valuable information about the machine lin- Y. Alexahin, E. Gianfelice-Wendt (Fermilab)
ear and non-linear optics. The recent upgrade
of the Beam Position Monitors system made it possible to exploit this technique also at Tevatron. A program
for the measurement and correction of the linear coupling based on this approach has been integrated in the TEVA-
TRON control system. With respect to the method based on the empirical adjustment of the strength of the skew
quadrupoles, the new method has the advantage of being faster and of allowing the measurement of the coupling
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