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Abstract  

It has been observed that the intensities of the gamma-rays emitted in the alpha-decay of 245Cm reported in the literature result in calculated concentrations that do not agree with those obtained via other methods. In this work, a 245Cm sample was chemically isolated from a sample of 249Cf, and the gamma-ray intensities were measured relative to the alpha-particle emission rate of the resulting source; there is a systematic bias relative to the literature intensities of approximately 8%. In addition, gamma-rays that have never before been observed in the decay of 245Cm are placed in the level scheme of the decay product, 241Pu.

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Abstract  

A comprehensive radiochemical isolation procedure and data analysis/interpretation method for the nuclear forensic investigation of Th has been developed. The protocol includes sample dissolution, chemical separation, nuclear counting techniques, consideration of isotopic parent-daughter equilibria, and data interpretation tactics. Practical application of the technology was demonstrated by analyses of a questioned specimen confiscated at an illegal drug synthesis laboratory by law enforcement authorities.

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Abstract  

A new procedure to isolate carrier-free isotopes of Nb and Ta after a 12-MeV proton bombardment of a natural Hf foil has been considered. The cross section of the corresponding natHf(p,x)179Ta reaction has been estimated for the first time as 5.4 ± 0.5 mb. The isotopes that were produced were subsequently used for development of procedures for the chemical characterization of element 105 (Db). HF/HNO3 and HNO3/H2O2 media have been chosen and the parameters of the experiments have been optimized. Based on the results obtained in this work, off-line experimental procedures have been proposed for the evaluation of the chemical behavior of Db.

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Abstract  

Two procedures are described for fast separations of berkelium from complex mixtures of reaction products arising from heavy ion reactions, such as18O+248Cm. The first procedure uses a combination of several extraction steps with a final separation on a cation exchanger, the second procedure starts with an anion exchange column which is followed by multiple extractions in different media. The elements separated in the different steps were analyzed and overall decontamination factors are given.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: P. Wilk, J. Landrum, D. Shaughnessy, J. Kenneally, N. Stoyer, M. Stoyer, K. Moody, N. Aksenov, G. Bozhikov, E. Tereshatov, G. Vostokin, S. Shishkin, and S. Dmitriev

Abstract  

A chemical separation method based on reversed-phase chromatography has been developed to separate the group five elements from the reaction products produced in the bombardment of 243Am with 48Ca ions. Decontamination factors on the order of 106 were achieved for group-three elements such as americium, and 107 or more for selected reaction products as measured by gamma-ray spectrometry pre-and post-chemistry. Details of the chemical separation scheme are discussed and compared to previously reported results.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: J. McAninch, A. Marchetti, B. Bergquist, N. Stoyer, G. Nimz, M. Caffee, R. Finkel, K. Moody, E. Sideras-Haddad, B. Buchholz, B. Esser, and I. Proctor

Abstract  

Accelerator mass spectrometry (AMS) is an established technique for the detection of long-lived radionuclides at environmental levels. At LLNL, planned facility upgrades and advances in detection techniques are allowing us to explore the applicability of AMS to isotopes not previously pursued. One such isotope is99Tc. We have performed a number of preliminary tests to examine the technical feasibility of AMS for the detection of99Tc. The questions addressed were negative ion production in the cesium sputter source, transport efficiency for the ions through the spectrometer, and detection efficiency for99Tc ions after the spectrometer. Based on the positive results of these tests, we have begun to develo measurement protocol.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: P. Grant, K. Moody, I. Hutcheon, D. Phinney, R. Whipple, J. Haas, A. Alcaraz, J. Andrews, G. Klunder, R. Russo, T. Fickies, G. Pelkey, B. Andresen, D. Kruchten, and S. Cantlin

Abstract  

Over the past several years, the Livermore Forensic Science Center has conducted analyses of nuclear-related samples in conjunction with domestic and international criminal investigations. Law enforcement officials have sought conventional and nuclear-forensic analyses of questioned specimens that have typically consisted of miscellaneous metal species or actinide salts. The investigated activities have included nuclear smuggling and the proliferation of alleged fissionable materials, nonradioactive hoaxes such as “Red Mercury,” and the interdiction of illegal laboratories engaged in methamphetamine synthesis.

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