First Indirect Drive Experiment Using a Six-Cylinder-Port Hohlraum.

The new hohlraum experimental platform and the quasi-3D simulation model are developed to enable the study of the indirect drive experiment using the six-cylinder-port hohlraum for the first time. It is also the first implosion experiment for the six laser-entrance-hole hohlraum to effectively use all the laser beams of the laser facility that is primarily designed for the cylindrical hohlraum. The experiments performed at the 100 kJ Laser Facility produce a peak hohlraum radiation temperature of ∼222 eV for ∼80 kJ and 2 ns square laser pulse. The inferred x-ray conversion efficiency η∼87% is similar to the cylindrical hohlraum and higher than the octahedral spherical hohlraum at the same laser facility, while the low laser backscatter is similar to the outer cone of the cylindrical hohlraum. The hohlraum radiation temperature and M-band (>1.6 keV) flux can be well reproduced by the quasi-3D simulation. The variations of the yield-over-clean and the hot spot shape can also be semiquantitatively explained by the calculated major radiation asymmetry of the quasi-3D simulation. Our work demonstrates the capability for the study of the indirect drive with the six-cylinder-port hohlraum at the cylindrically configured laser facility, which is essential for numerically assessing the laser energy required by the ignition-scale six-cylinder-port hohlraum.

Measurement of Time-Dependent Drive Flux on the Capsule for Indirectly Driven Inertial Confinement Fusion Experiments.

A new method for measuring the time-dependent drive flux at the hohlraum center is proposed as a better alternative to conventional wall-based techniques. The drive flux here is obtained by simultaneous measurement of the reemitted flux and shock velocity from a three-layered "cakelike" sample. With these two independent observables, the influence induced by the uncertainty of the material parameters of the sample can be effectively decreased. The influence from the closure of the laser entrance hole, which was the main challenge in conventional wall-based techniques, was avoided through localized reemitted flux measurement, facilitating drive flux measurement throughout the entire time history. These studies pave a new way for probing the time-dependent drive flux, for both cylindrical hohlraums and novel hohlraums with six laser entrance holes.

First exploration of radiation temperatures of the laser spot, re-emitting wall and entire hohlraum drive source.

This study explores the radiation field temperatures introduced by the laser spot, the re-emitting wall in a hohlraum and the entire hohlraum drive source. This investigation, which is the first of its kind, is based on the radiation fluxes from the laser spot and the re-emitting wall, which have been accurately measured using time- and space-resolving flux detectors in a recent work, and additional flux data. The temperature difference between the laser spot and the entire hohlraum drive source was 6.08-35.35% of the temperature of the latter throughout the entire laser pulse, whilst that for the re-emitting wall was 3.90-12.81%. The radiation temperature of the cooler re-emitting wall had more influence on the temperature increase of the entire hohlraum drive source than the hot laser-spot temperature, which has been quantitatively discussed. Experimentally, we established the average distributions of the temperature fields of all the emitting sources, namely laser spot and re-emitting wall, of the irradiating fluxes on the capsule region in the hohlraum radiation field. This important progress in the exploration of radiation temperature distributions within a hohlraum will provide a foundation for determination of the irradiating radiation on the capsule and evaluation of capsule symmetry.

A novel three-axis cylindrical hohlraum designed for inertial confinement fusion ignition.

A novel ignition hohlraum for indirect-drive inertial confinement fusion is proposed, which is named three-axis cylindrical hohlraum (TACH). TACH is a kind of 6 laser entrance holes (LEHs) hohlraum, which is orthogonally jointed of three cylindrical hohlraums. Laser beams are injected through every entrance hole with the same incident angle of 55°. A view-factor simulation result shows that the time-varying drive asymmetry of TACH is less than 1.0% in the whole drive pulse period without any supplementary technology. Coupling efficiency of TACH is close to that of 6 LEHs spherical hohlraum with corresponding size. Its plasma-filling time is close to that of typical cylindrical ignition hohlraum. Its laser plasma interaction has as low backscattering as the outer cone of the cylindrical ignition hohlraum. Therefore, TACH combines most advantages of various hohlraums and has little predictable risk, providing an important competitive candidate for ignition hohlraum.

Citrate Accumulation-Related Gene Expression and/or Enzyme Activity Analysis Combined With Metabolomics Provide a Novel Insight for an Orange Mutant.

'Hong Anliu' (HAL, Citrus sinensis cv. Hong Anliu) is a bud mutant of 'Anliu' (AL), characterized by a comprehensive metabolite alteration, such as lower accumulation of citrate, high accumulation of lycopene and soluble sugars in fruit juice sacs. Due to carboxylic acid metabolism connects other metabolite biosynthesis and/or catabolism networks, we therefore focused analyzing citrate accumulation-related gene expression profiles and/or enzyme activities, along with metabolic fingerprinting between 'HAL' and 'AL'. Compared with 'AL', the transcript levels of citrate biosynthesis- and utilization-related genes and/or the activities of their respective enzymes such as citrate synthase, cytosol aconitase and ATP-citrate lyase were significantly higher in 'HAL'. Nevertheless, the mitochondrial aconitase activity, the gene transcript levels of proton pumps, including vacuolar H(+)-ATPase, vacuolar H(+)-PPase, and the juice sac-predominant p-type proton pump gene (CsPH8) were significantly lower in 'HAL'. These results implied that 'HAL' has higher abilities for citrate biosynthesis and utilization, but lower ability for the citrate uptake into vacuole compared with 'AL'. Combined with the metabolites-analyzing results, a model was then established and suggested that the reduction in proton pump activity is the key factor for the low citrate accumulation and the comprehensive metabolite alterations as well in 'HAL'.

New two-dimensional space-resolving flux detection technique for measurement of hohlraum inner radiation in Shenguang-III prototype.

The space-resolving measurement of X-ray flux from a specific area (laser spot, re-emitting wall, or capsule) inside the hohlraum is an ongoing and critical problem in indirectly driven inertial-confinement fusion experiments. In this work, we developed a new two-dimensional space-resolving flux detection technique to measure the X-ray flux from specific areas inside the hohlraum by using the time- and space-resolving flux detector (SRFD). In two typical hohlraum experiments conducted at the Shenguang-III prototype laser facility, the X-ray flux and radiation temperature from an area 0.2 mm in diameter inside the hohlraum were measured through the laser entrance hole (LEH). The different flux intensities and radiation temperatures detected using the SRFD from the inner area of the LEH were compared with the result measured using the flat-response X-ray detector from the entire LEH. This comparison was also analyzed theoretically. The inner area detected using the SRFD was found to be the re-emitting wall area alone. This important improvement in space-resolving X-ray flux measurement will enhance the current X-ray flux space characterization techniques, thereby furthering the quantitative understanding of X-ray flux space behavior in the hohlraum.

Direct measurement of x-ray flux for a pre-specified highly-resolved region in hohlraum.

A space-resolving flux detector (SRFD) is developed to measure the X-ray flux emitted from a specified region in hohlraum with a high resolution up to 0.11mm for the first time. This novel detector has been used successfully to measure the distinct X-ray fluxes emitted from hot laser spot and cooler re-emitting region simultaneously, in the hohlraum experiments on SGIII prototype laser facility. According to our experiments, the ratio of laser spot flux to re-emitted flux shows a strong time-dependent behavior, and the area-weighted flux post-processed from the measured laser spot flux and re-emitting wall flux agrees with that measured from Laser Entrance Hole by using flat-response X-ray detector (F-XRD). The experimental observations is reestablished by our two-dimensional hydrodynamic simulations and is well understood with the power balance relationship.