OZSPEC-2: An improved broadband high-resolution elliptical crystal x-ray spectrometer for high-energy density physics experiments (invited)

• Published in: Review of scientific instruments 2008-10, Vol.79 (10), p.10E303-10E303-6
• Main Authors: Heeter, R. F., Anderson, S. G., Booth, R., Brown, G. V., Emig, J., Fulkerson, S., McCarville, T., Norman, D., Schneider, M. B., Young, B. K. F.
• Format: Article
• Language: English
• Subjects: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CRYSTALS; DESIGN; EMISSION SPECTRA; ENERGY DENSITY; HARD X RADIATION; ICF DEVICES; INERTIAL CONFINEMENT; INERTIAL FUSION DRIVERS; MICROCHANNEL ELECTRON MULTIPLIERS; ONE-DIMENSIONAL CALCULATIONS; OPACITY; PLASMA; RESOLUTION; X-RAY SPECTRA; X-RAY SPECTROMETERS
• ISSN: 0034-6748; 1089-7623
• DOI: 10.1063/1.2981180

A novel time, space, and energy-resolved x-ray spectrometer has been developed which produces, in a single snapshot, a broadband and relatively calibrated spectrum of the x-ray emission from a high-energy density laboratory plasma. The opacity zipper spectrometer (OZSPEC-1) records a nearly continuous spectrum for x-ray energies from 240 to 5800 eV in a single shot. The second-generation OZSPEC-2, detailed in this work, records fully continuous spectra on a single shot from any two of these three bands: 270-650, 660-1580, and 1960 - 4720 eV . These instruments thus record thermal and line radiation from a wide range of plasmas. These instruments' single-shot bandwidth is unmatched in a time-gated spectrometer; conversely, other broadband instruments are either time-integrated (using crystals or gratings), lack spectral resolution (diode arrays), or cover a lower energy band (gratings). The OZSPECs are based on the zipper detector, a large-format ( 100 × 35 mm ) gated microchannel plate detector, with spectra dispersed along the 100 mm dimension. OZSPEC-1 and -2 both use elliptically bent crystals of OHM, RAP, and/or PET. Individual spectra are gated in 100 ps . OZSPEC-2 provides one-dimensional spatial imaging with 30 - 50 μ m resolution over a 1500 μ m field of view at the source. The elliptical crystal design yields broad spectral coverage with resolution E ∕ Δ E > 500 , strong rejection of hard x-ray backgrounds, and negligible source broadening for extended sources. Near-term applications include plasma opacity measurements, detailed spectra of inertial fusion Hohlraums , and laboratory astrophysics experiments.