Spectroscopy of laser-plasma accelerated electrons: a novel concept based on Thomson scattering

The spectrum of relativistic electron bunches with large energy dispersion, like the ones usually generated with laser-plasma acceleration processes, is difficult to obtain with conventional methods. A novel spectroscopic concept, based on the analysis of the photons generated by Thomson scattering of a probe laser pulse by the electron bunch, is presented. The feasibility of a single-pulse spectrometer, using an energy-calibrated charge coupled device as detector, is investigated. Numerical simulations performed in conditions typical of a real experiment show the effectiveness and accuracy of the new method.