Capsule pie diagrams for the nominal “Rev 5” ignition capsule (left) and symmetry capsule (right) with silicon dopant layers. Dimensions are in microns. Both capsules use the same podium profile for the Si dopant, with clean CH (plastic) on the inner-most and outer-most layers. The central layers have nominally 1%, 2%, and 1% silicon (by atom) doped in the plastic.
Velocity vs. ablator center-of-mass radius RCoM for two 1D HYDRA calculations using the same x-ray drive source. The black curve shows the center-of-mass velocity for a symmetry capsule—this quantity is measured in backlit convergent ablator experiments. The red curve shows the mass-average fuel velocity Vfuel for the equivalent DT-layered ignition capsule. The fuel velocity is higher than the ablator velocity due to convergence effects at small radius. The maximum of Vfuel is typically 10%–15% higher than that of VCoM .
Rocket curves for a thicker (215 μm) DT capsule and (229 μm) symcap from two 1D HYDRA calculations that use the same x-ray drive source. The blue dashed curve is simply Eq. (5) , , and passes through the HYDRA symcap simulation. The ignition mass/velocity goal , M = 0.25 mg is shown as a red ×. The error bar represents the total uncertainty in inferring the mass from a convergent ablator experiment. This error bar is not meant to represent a tolerance on the ignition mass goal.
Rocket curves for nominal ( ) symcaps from twelve convergent ablator experiments and their corresponding 2D post-shot HYDRA calculations. The twelve shots vary in laser peak power, capsule dopant concentration, LEH size, and hohlraum wall material. The data generally lie on the simulated rocket curves within the measurement uncertainty. The thickness of the bundle of simulated rocket curves is in mass or in velocity.
Rocket curves for nominal ( ) symcaps from twelve convergent ablator experiments and their corresponding 2D post-shot HYDRA calculations, focused near the end of the acceleration phase. The symcap mass/velocity goal, , M = 0.46 mg, is shown by the black ×. A HYDRA simulation of the nominal Si capsule that reaches the symcap velocity goal is shown by the red dashed line. This rocket curve reaches with mass below the goal of M = 0.46 mg.
Rocket curves for nominal ( ) and thick ( ) symcaps from twelve convergent ablator experiments designed to reach and their corresponding 2D post-shot HYDRA calculations. The red curves and black data points are a subset of the twelve experiments shown in Fig. 5 . The red dashed line is as in 5. The blue data points and solid curve are results for a backlit experiment with a 20 μm thicker ( ) capsule. The blue dashed curve is a simulation of this thicker capsule driven to the symcap velocity goal, .
Radiation brightness temperature TRAD inferred from the DANTE and SXI diagnostics (cf. Eq. (7) ) for the 520 TW symcap shot N120705. The TRAD for one of the frequency-dependent-sources (FDS) used in the 1D HYDRA flux-scaling is shown in red for comparison. The launch time, rate-of-rise, and general shape of the FDS TRAD are taken from the experimental data. The 1D HYDRA simulation using this particular source reproduces the measured x-ray bang-time of N120705. The maximum TR of this source is slightly lower than the data using an error bar to represent thecombined uncertainty of DANTE, SXI, and the analysis method approximations.
Velocity vs. x-ray bang-time for symmetry capsule shot N120705 and convergent ablator shot N121007, compared with a 1D HYDRA flux-scaling. The convergent ablator data for center-of-mass velocity and x-ray bang-time “pin” the scaling, allowing a velocity estimate for the higher-power N120705 shot based only on its bang-time.
Laser power delivered to the hohlraum for the symcap shot N120705 and the corresponding convergent ablator shot N121007. The average peak-power was 520 TW for N120705 and 470 TW for N121007. The requested power for N121007 was reduced from 514 TW to 500 TW. The power was further reduced due to diverting two quads to the backlighter foil and losing a third quad to mechanical failure. These laser pulses correspond to the × symbols in Fig. 8 .
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