Measurement of the anisotropy of the electron distribution of a laser-produced AI plasma using space-resolved plasma polarization spectroscopy

If the electron distribution has anisotropy, the emissions from such plasma have some degree of polarization. To study the anisotropy of the electron distribution of laser produced plasmas, a polarization-resolved spectrometer was constructed and used to measure the degree of the polarization of emission from laser produced A1 plasmas. The laser was focused on the target surface and the diameter of the laser spot on the target surface was about 0.26 Mn. So the power density on the target surface was about 5 GW/cm2. Using dichroic polarizer in front of the entrance slit of the spectrometer or placing a calcite crystal in front of the entrance slit of a Czerny-Turner spectrometer, the polarization of the spectrum is resolved. the focal length of the Czerny-Turner spectrometer is 1 m with a measured spectral resolution of 0.46 nm at 365 nm.