The OMEGA-extended performance streaked optical pyrometer with spectral resolution

Optical diagnostics play critical roles in the dynamic compression experiments regularly carried out on large-scale laser facilities like OMEGA-Extended Performance (EP). They provide time-resolved information about a sample's temperature, pressure, and reflectivity. Most often, these properties have been inferred from measurements made at a single probe wavelength or without spectral resolution. The streaked optical pyrometer with spectral resolution (SOP-Spec) was recently brought online to measure time-resolved optical spectra in the 475-750 nm range, allowing the first spectrally resolved broadband measurements of laser compressed materials on EP. SOP-Spec will be used to investigate the spectrally resolved emissivities of matter at high energy density conditions, which have largely been assumed to be a gray body in previous studies. The diagnostic is capable of recording emission spectra from surfaces at temperatures >3000 K with better than 16 nm spectral resolution and 20 ps temporal resolution. The design and calibration of the diagnostic are described, and results on the spectral emission of shocked quartz up to 900 GPa are reported.