Description of modulated beam dynamics
Abstract
General formalism for describing dynamics of modulated beams along linear beamlines is developed. We describe modulated beams with spectral distribution function which represents Fourier transform of the conventional beam distribution function in the 6dimensional phase space. The introduced spectral distribution function is localized in some region of the spectral domain for nearly monochromatic modulations and it can be characterized with a small number of typical parameters which we choose to be the lowest order moments of the spectral distribution. We study evolution of modulated beams in linear beamlines and find that characteristic spectral parameters transform linearly. The developed approach significantly simplifies analysis of various schemes proposed for seeding Xray free electron lasers. We use this approach to study several recently proposed schemes and find the bandwidth of the output bunching in each case.
 Publication:

arXiv eprints
 Pub Date:
 December 2011
 arXiv:
 arXiv:1112.0553
 Bibcode:
 2011arXiv1112.0553Y
 Keywords:

 Physics  Accelerator Physics
 EPrint:
 12 pages, 4 figures