Speaker
Mr
Henrik Ekerfelt
(Lund University)
Description
One challenge in the development of laser wakefield accelerators is to
demonstrate sufficient control and reproducibility of the beam
parameters. Many schemes of controlled trapping of electrons have been
proposed and implemented, aiming to improve control and
reproducibility. Here we report on a numerical study of trapping in density
down-ramps, as a continuation of our previous experimental study in which
remarkable stability, using this trapping mechanism, was
observed.
We demonstrate that trapping using density down-ramps allows for tuning of
several electron bunch parameters by varying the properties of the density
down-ramp. We show that the electron bunch length is determined by the
difference in density before and after the ramp. The transverse emittance of
the bunch is controlled by the steepness of the ramp. Finally, the amount of
trapped charge depends both on the density difference and on the steepness
of the ramp. We emphasize that both parameters of the density ramp are
feasible to vary experimentally. This tunable electron accelerator makes it
suitable for a wide range of applications, from those requiring short
pulse length and low emittance, such as the FELs, to those
requiring high-charge, large-emittance bunches to maximize betatron x-ray
generation.
Primary author
Mr
Henrik Ekerfelt
(Lund University)
Co-authors
Isabel Gallardo Gonzalez
(Lund University)
Mr
Martin Hansson
(Atomic Physics, Lund University)
Dr
Olle Lundh
(Lund University)
Dr
Xavier Davoine
(CEA DAM DIF)
