Evaluation of the HTR-10 Reactor as a Benchmark for Physics Code QA

The HTR-10 is a small (10 MWt) pebble-bed research reactor intended to develop pebble-bed reactor (PBR) technology in China. It will be used to test and develop fuel, verify PBR safety features, demonstrate combined electricity production and co-generation of heat, and provide experience in PBR design, operation, and construction. As the only currently operating PBR in the world, the HTR-10 can provide data of great interest to everyone involved in PBR technology. In particular, if it yields data of sufficient quality, it can be used as a benchmark for assessing the accuracy of computer codes proposed for use in PBR analysis. This paper summarizes the evaluation for the International Reactor Physics Experiment Evaluation Project (IRPhEP) of data obtained in measurements of the HTR-10’s initial criticality experiment for use as benchmarks for reactor physics codes

X-ray line emission from laser-produced spherical plasma flows

A numerical model has been developed for calculating x-ray line emission from spherical plasma flows and has been applied to a laser-heated, ablating aluminum target. The results are in good agreement with previous experimental work. The intensity ratios of the dominant lines are predicted in good agreement with experiment. A novel effect, not yet observed, is predicted in the interaction of nearby lines, here an Hα doublet: through Doppler shift caused by plasma flow one line absorbs the other. This line obscuring effect has potential applications to diagnosing details of ablative flows in x-ray lasing and inertial confinement fusion experiments. The main features of the model are plasma parameters obtained through a Lagrangian hydrodynamics model, radiative transport by multienergy and multi-impact parameter ray groups, and self-consistent, time-dependent computation of ion and ion energy-level populations. Approximately 100 energy groups per line resolve line structure and show Doppler effects. The scalings involved in extending this work to other plasma conditions and materials are discussed. © 1989 American Institute of Physics

The polymer-supported MacDonald-type porphyrin synthesis: Coupling of two dissimilar dipyrromethanes

Syntheses of two completely unsymmetrical porphyrins have been achieved by MacDonald-type condensations of polymer-bound 9-formyldipyrromethanes with dissimilar solution-phase dipyrromethanes. The chemoselectivity of the process depends on the nature of the substituents at the α positions of the substrates. (C) 2000 Elsevier Science Ltd

Replication Walco and Risen (2017) @ BYU-Idaho Fall 2018

We are replicating Walco, D. & Risen, J. The Empirical Case for Acquiescing to Intuition, Study 3 (Blackjack)

Analysis, Modeling, and Design of Short-Wavelength Laser-Plasma Experiments

We present analysis and LASNEX modeling of two experiments designed to explore the mechanisms and scaling of laser-plasma coupling in high-Z plasmas. The first used layered Au-on-CH spheres irradiated symmetrically using the Omega (Laboratory for Laser Energetics) 0.35 ..mu..m laser to observe the x-ray emission and energy penetration in gold plasmas. Measurements of the subkilovolt and kilovolt emission from targets with varying Au-coating thicknesses were made using diagnostics of varying spectral, temporal, and spatial resolution. The results indicate that the x-ray conversion efficiency is a function of target size, with larger targets yielding x-ray emission in excellent agreement with calculations. The x-ray emission fall-off with decreasing gold thickness agrees well with predictions. The second experiment used the Novette (Lawrence Livermore National Laboratory) laser to irradiate solid gold disk targets, examining wavelength scaling to 0.26 ..mu..m. The measured subkilovolt x-ray emission is in good agreement with calculations using mildly inhibited thermal electron transport, indicating enhanced target coupling, compared with previous experiments using smaller spot sizes. The experiment also indicates very low suprathermal electron populations, on the order of 0.1% at about 30 keV effective temperature. Finally, we present preliminary plans and designs for experiments which will use the Aurora 5 kJ, 5 ns, 0.25 ..mu..m KrF laser now being constructed at Los Alamos