Quasi-monoenergetic femtosecond photon sources from Thomson Scattering using laser plasma accelerators and plasma channels

摘要

Narrow bandwidth, high energy photon sources can be generated by Thomsonscattering of laser light from energetic electrons, and detailed control of theinteraction is needed to produce high quality sources. We present analyticcalculations of the energy-angular spectra and photon yield that parametrizethe influences of the electron and laser beam parameters to allow sourcedesign. These calculations, combined with numerical simulations, are applied toevaluate sources using conventional scattering in vacuum and methods forimproving the source via laser waveguides or plasma channels. We show that thephoton flux can be greatly increased by using a plasma channel to guide thelaser during the interaction. Conversely, we show that to produce a givennumber of photons, the required laser energy can be reduced by an order ofmagnitude through the use of a plasma channel. In addition, we show that aplasma can be used as a compact beam dump, in which the electron beam isdecelerated in a short distance, thereby greatly reducing radiation shielding.Realistic experimental errors such as transverse jitter are quantitativelyshown to be tolerable. Examples of designs for sources capable of performingnuclear resonance fluorescence and photofission are provided.