M.Sc Student | Grinenko Alon |
---|---|
Subject | The Interaction of Electrons with Radiation in an Active Medium |
Department | Department of Electrical Engineering | Supervisor | Professor Levi Schachter |
The present generation
of particle accelerators requires gradients of levels which are at least one
order of magnitude higher than gradients available today. The need for a high
gradient on one hand and power levels below the breakdown threshold on the
other hand, pushes the operating frequency upwards. Therefore acceleration of
electrons by radiation at optical wavelengths is one of the promising
alternatives for future electron accelerators. The essence of the idea is to
inject a charged particle in an active medium, and in this way the energy
stored in the medium could be transferred to a charged particle without prior
generation of radiation.
In this text a theoretical model based on the set of equations which describe the dynamics of electrons in the presence of electromagnetic wave propagating in an active medium is examined. This formalism, is based on the assumption that there is a single electromagnetic mode that propagates in the interaction region. It is shown that due to a double selection process, a single space mode exists, which is amplified by the medium and interacts with the electron beam.
Furthermore, the
interaction model is extended to account for the effects of spontaneously
emitted radiation, and the signal to noise ratio of the system is analyzed. Two
possible systems have been examined in the computer simulations: a system
utilizing
as
an active medium and a system utilizing
as an active medium.
Gradient levels above are obtained in
simulations of
system and acceleration of
beams of
particles to
is predicted
in
system
in which population inversion density resulting in linear gain of up to
can be obtained
for a certain set of system parameters. In the
system, the relatively low linear
gain of up to
, limits the effect of the active
medium to gradient levels below
.
show, that by varying
the beam modulation in the range of
, the
at the system output can
be increased from
to
in
medium with
linear gain. Other
parameters, such as structure geometry and beam average energy are shown to
have a small effect on the