Plasma Spectroscopy on Hydrogen-Carbon-Oxygen Foam Targets Driven by Laser-Generated Hohlraum Radiation

Abstract

The laboratory generation and diagnosis of uniform near-critical-density (NCD) plasmas play critical roles in various studies and applications, such as fusion science, high energy density physics, astrophysics as well as relativistic electron beam generation. Here we successfully generated the quasistatic NCD plasma sample by heating a low-density tri-cellulose acetate (TCA) foam with the high-power-laser-driven hohlraum radiation. The temperature of the hohlraum is determined to be 20 eV by analyzing the spectra obtained with the transmission grating spectrometer. The single-order diffraction grating was employed to eliminate the high-order disturbance. The temperature of the heated foam is determined to be T = 16.8 ± 1.1 eV by analyzing the high-resolution spectra obtained with a flat-field grating spectrometer. The electron density of the heated foam is about N e = 4.0 ± 0.3 × 10 20 cm − 3 under the reasonable assumption of constant mass density.

Proton-Boron Fusion: A Dark Horse in the Fusion Race Shows Yield Much Beyond Expectation

“…Hence, a large-scale, ns-long-living, homogeneous and quasi-static boron doped plasma is generated. In order to characterize the plasma state, emission spectra of the gold hohlraum and the foam target were measured by a transmission and a flat-field grating spectrometer (TGS and FGS) coupled to a calibrated image plate (IP, type BAS-TR), respectively [30,31]. The hohlraum radiation agrees well with a black body radiation at 19 eV.…”