Observation of laser-driven electron acceleration

It is extremely important to develop new X-ray sources for future X-ray spectrometry. One promising direction is a table-top synchrotron X-ray source, which consists of a high-power pulse laser and an undulator. The method uses acceleration of electrons by pulse laser photons. The idea becomes realistic once the energy reaches GeV and other properties such as stability, emittance etc are improved sufficiently. For such development, it is indispensable to establish the method for quantitatively investigating the structure of the electron beam in time and space. Recently, a German group succeeded in taking snapshots of the magnetic field generated by an accelerated electron bunch and simultaneously of a plasma wave by a combination of two techniques: time-resolved polarimetry and plasma shadowgraphy. For more information, see the paper, "Real-time observation of laser-driven electron acceleration", A. Buck et al., Nature Physics (Published online, March 13, 2011 DOI:10.1038/nphys1942).