Design of a double dipole electron spectrometer

With the increase of laser power reaching petawatt-level in several facilities and with more facilities being commissioned, there is a need for accurate electron beam diagnostics of the laser wakefield accelerator (LWFA), which is now an important tool for high field physics. Electrons in the range of several 100s of GeV are expected at these power levels. Precise diagnostic systems are also required to enable applications such as advanced radiation sources. Accurate measurement of the energy spread of electron beams will help pave the way towards LWFA based free-electron lasers and plasma based coherent radiation source. We propose an innovative double dipole spectrometer suitable for characterizing bunches produced using a petawatt class laser.