A novel 45-channel electron spectrometer for high intensity laser-plasma interaction studies

We have developed a magnetic spectrometer to characterize the hot electrons generated in high-intensity (> 10(18) W/cm(2)) laser-plasma interaction experiments. It comprises a dispersive element consisting of a permanent dipole magnet and an electron detector incorporating 45 scintillating/light-guiding plastic fibers connected to a cooled charged-coupled device camera. The main features of this instrument are high spectral resolution, low sensitivity to x and gamma rays, and versatility due to its compact design. Performance and operational capabilities are illustrated based on experimental results in which electron energy-spectra in the range of 520 keV to 12.6 MeV were obtained with an energy resolution of 10% and a detection threshold of 10(6) electrons per MeV. (C) 2000 American Institute of Physics. [S0034-6748(00)04804-8].