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Determination of relative krypton fission product yields from 14 MeV neutron induced fission of 238 U at the National Ignition Facility
Precisely-known fission yield distributions are needed to determine a fissioning isotope and the incident neutron energy in nuclear security applications. 14 MeV neutrons from DT fusion at the National Ignition Facility (NIF) induce fission in depleted uranium (DU) contained in the target assembly hohlraum. The fission yields of Kr isotopes (85m, 87, 88, and 89) are measured relative to the cumulative yield of 88Kr and compared to previously tabulated values. Here, the results from this experiment and England and Rider are in agreement, except for the 85m Kr/ 88 Kr ratio, which may be the result of incorrect nuclear data.
On krypton-doped capsule implosion experiments at the National Ignition Facility
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Manifestation of postcollision interaction in Krypton LMN Auger spectra following K-shell photoionization
In this work, we report on an experimental and theoretical study of post-collision interaction (PCI) effects on L 2 -M 4,5 N 2,3 Auger electrons measured above the Kr K-edge in which L 2 vacancies are primarily generated by KL 2 x-ray emission. Such cascade processes, in which a deep inner-shell vacancy decays first by x-ray emission followed by Auger electron emission, is a strong decay mode in heavy atoms. The L 2 -M 4,5 N 2,3 Auger electron peak is observed to become increasingly asymmetric with a shifting peak maximum as the absorbed x-ray energy approaches the K-shell ionization threshold. This is attributed to PCI energy exchanges of the Auger electron with the 1s photoelectron. To model the PCI effects, we have applied a semiclassical approach modified to account for the combined lifetimes of the K and L 2 hole states. In addition, our analysis treats several closely spaced Auger transitions with final ionic states having different terms and angular momenta.
Solidification and fcc to metastable hcp phase transition in krypton under variable compression rates
In this work, we present time-resolved synchrotron x-ray diffraction measurements to study kinetics associated with the liquid-solid and solid-solid high-pressure phase transitions in Kr under dynamic loading in a dynamic-diamond anvil cell. The results show a strong compression-rate dependence of the solidification/melting process in liquid Kr. The analysis of the compression-rate dependent melting/solidification, using an Avrami equation with the parameter n=1, indicates a spontaneous nucleation and one-dimensional growth mechanism. In contrast, the face-centered-cubic to metastable hexagonal close-packed transition in solid Kr occurs rapidly at ~0.8 GPa near the melting line, which has negligible compression-rate dependence within the range of compression rates studied (0.004–13 GPa/s).
Study of Stark Broadening of Krypton Helium-beta Lines and Estimation of Electron Density and Temperature in NIF Compressed Capsules
Numerical data used to draw the figures in the manuscript
Transmission Electron Microscopy Investigation of Krypton Bubbles in Polycrystalline CeO 2
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Cost-Benefit Assessment of Krypton and Xenon Recovery from Aqueous Reprocessing
The purpose of this paper is to provide an understanding of the cost-benefit of capturing Kr and Xe from the existing process of aqueous reprocessing of UNF. The study accomplishes this with a market assessment of Xe prices and volumes today, coupled with a cost estimate of Kr and Xe capture out of cryogenic distillation within aqueous reprocessing. The market assessment shows that the average price of Xe is about $\$ $60/L while the average price of Kr is about $\$ $1/L. The assessment also shows that the market structure for Xe is one of oligopoly, in other words, very few suppliers to the Xe market. The assessment shows growing demand for Xe, particularly in medical applications like anesthesia. The cost assessment finds the unit cost of Xe to range from $\$ $71.50/L to $\$ $131.13/L. This range is only slightly above the current range of market prices today, and with growing demand for Xe, prices could reach the range it would take to support extraction of Xe from aqueous reprocessing. On the other hand, the estimated cost range for Kr is $\$ $830.15/L up to $\$ $1,522.52/L, which far exceeds the range of market prices for Kr. However, as the text notes, Kr capture is already part of aqueous reprocessing so these costs are sunk costs (already incurred) whereas the cost estimates for Xe are marginal cost (if Xe is desired, then the cost estimate would result from the Xe capture).
Krypton-85 chronometry of spent nuclear fuel
We describe the use of the radionuclide 85 Kr, which is produced by nuclear fission and has a half-life of 10.76 years, to determine the age of spent nuclear fuel. The method is based on mass-spectrometric measurement of the relative abundance of fissiogenic Kr isotopes extracted from a fuel sample, and we show that it can be applied to micron-scale particles of spent fuel that are analogous to particles that have been released into the environment from various nuclear facilities in the past. 85 Kr chronometry is potentially valuable for identifying and attributing nuclear materials, grouping samples into collections of common origin that can be used to reconstruct the origin and irradiation history of the material, and verifying declared nuclear activities in the context of international monitoring programs.
Excitation cross section for some of the doubly ionized states of argon, neon, and krypton by fast electrons.
Excitation cross section for double ionized states of Ar, Ne and Kr due to fast electron impingement on neutral atom
Transport coefficients of partially ionized krypton and xenon.
Partially ionized Kr and Xe transport coefficients for various pressures and at high temperatures computed on basis of charged particle cross sections
Experimental investigation of momentum exchange between argon and krypton beams incident on clean gold surfaces
Electromagnetic torsion balance measurement of forces exerted on clean Au surfaces by monoenergetic steady state Ar and Kr beams, calculating thermal accommodation coefficients
Multistate impact-parameter calculation of atom-atom excitation cross sections - Excitation of atomic hydrogen by neon, argon, and krypton
Hydrogen and inert gas atoms collisional excitation cross sections calculated by multistate impact parameter approximation
Gas chromatographic determination of hydrogen, nitrogen, oxygen, methane, krypton, and carbon dioxide at room temperature
Hydrogen, N, O, Kr methane and carbon dioxide gas chromatographic examination, discussing life detection device for Mars landing
Born wave cross section calculations for the excitation of He/1 super 1 S/ to He/N super 1 L/ by helium, neon, argon and krypton
He excitation by He, Ne, Ar and Kr collisions, calculating first Born wave cross section
New CW ion laser transitions in argon, krypton, and xenon
CW ion laser transitions in Ar, Kr and Xe, tabulating threshold data