211 research outputs found
Laser polarization of positron beam
For a number of physical studies which are planned to be made with the next
generation colliders, it is necessary to use polarized beams of both electrons
and positrons. The problem of producing and acceleration of polarized electrons
may be considered to be solved, but the existing approaches to create polarized
positron beams do not ensure the parameters required. This work proposes a new
approach to produce polarized positron beams, which is based on the process of
multiple Compton backscattering of unpolarized ultrarelativistic positrons in
the field of intense circularly polarized laser wave
Resonant Diffraction Radiation from an Ultrarelativistic Particle Moving Close to a Tilted Grating
A simple model for calculating the diffraction radiation characteristics from
an ultrarelativistic charged particle moving close to a tilted ideally
conducting strip is developed. Resonant diffraction radiation (RDR) is treated
as a superposition of the radiation fields for periodically spaced strips. The
RDR characteristics have been calculated as a function of the number of grating
elements, tilted angle, and initial particle energy. An analogy with both the
resonant transition radiation in absorbing medium and the parametric X-ray
radiation is noted.Comment: 17 pages, 12 figures, RevTe
The experimental study of the surface current excitation under the influence of a relativistic electron electromagnetic field
The problem of the surface current excitation in a conductive targets by a
relativistic electron electric field as the origin of such radiation mechanisms
as diffraction and transition radiation of relativistic electron was considered
in frame of both surface current and pseudo-photon methods. The contradiction
between these viewpoints in respect to the surface current on the target
downstream surface necessitated the experimental test of this phenomenon. The
test performed on electron beam of the 6 MeV microtron showed, that not any
surface current is induced on the target downstream surface under the influence
of a relativistic electron electromagnetic field in contrast to the upstream
surface. This is important implication for the understanding of the forward
transition and diffraction radiation nature.Comment: Was Presented at the symposium Channeling 2008 (Charged and Neutral
Particles Channeling Phenomena), October 25 - November 1, 2008 Erice (Trapani
- Sicily), Italy, and was accepted for publication in proceedings of
symposiu
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