This chapter is intended to provide a general presentation of the atomic and nuclear processes responsible for X-ray line and gamma-ray line emission in various astrophysical environments. I consider line production from hot plasmas, from accelerated particle interactions , from the decay of radioactive nuclei synthesized in stars and from positron annihilation. Spectroscopic properties of thes...

The background induced by radioactive impurities of Tl and Bi in the source of the double beta experiment NEMO-3 has been investigated. New methods of data analysis which decrease the background from the above mentioned contamination are identified. The techniques can also be applied to other double beta decay Preprint submitted to Elsevier Science experiments capable of measuring independently...

‘The increased efficiency with which superweapons disperse radioactive materials is to some extent counter-acted by the delay in arrival of fallout from the high source cloud and the rapid rate of decay which occurs in the interim.’ – R.L. Stetson, E.A. Schuert, W.W. Perkins, T.H. Shirasawa, and H.K. Chan, Distribution and Intensity of Fallout, Operation Castle, Project 2.5a, U.S. Naval Radiolo...

Abstract In low count-rate experiments Gaussian statistics is often not appropriate. An example of likelihood analysis applied to determine the Kr activity using data from a low background liquid scintillator is presented. Uncertainties and upper limits calculation is shown together with a goodness-of-fit based on Monte Carlo and on the Smirnov-Cramer-Von Mises test. The likelihood ratio method...

This paper describes the design of a programmable stay-alone continuous radon monitoring system able to detect, count and store the amount of alpha particles with an energy of 5.49 MeV produced by the radioactive decay of environmental radon-222. It is included the electronic circuit design, the software development as well as the user interface and the hardware ensemble of all the system compo...

An interactive multimedia tool, Nuclides.net, has been developed at the Institute for Transuranium Elements. The Nuclides.net “integrated environment” is a suite of computer programs ranging from a powerful user-friendly interface, which allows the user to navigate the nuclides chart and explore the properties of nuclides, to various computational modules. Through this powerful interface, the u...

Comparison of ion-molecular reactions of free-phenyl cations generated by tritium β -decay with 2-methyl- and 2-phenylquinolines has been investigated. The reaction of direct nitrogen atom phenylation with the help of nucleogenic phenyl cations has been fulfilled for the first time and a new one-step synthesis of tritium-labeled N-phenyl-2-phenylquinolinium salt-lipophilic radioactive biologica...

Accurate partial gamma-ray production cross sections were determined for the prompt and radioactive product decay gamma rays following cold neutron capture in Tc. They can be used for non-destructive assay of technetium by prompt gamma activation analysis (PGAA) and neutron activation analysis (NAA), offering orders of magnitude higher analytical sensitivities than passive gamma-ray counting. A...

We present a set of new, semi-analytical solutions to simulate three-dimensional contaminant transport subject to first-order chain-decay reactions. The aquifer is assumed to be areally semi-infinite, but finite in thickness. The analytical solution can treat the transformation of contaminants into daughter products, leading to decay chains consisting of multiple contaminant species and various...

A method has been developed to load tellurium into liquid scintillator so as permit searches for neutrinoless double beta decay with high sensitivity. The approach involves the synthesis of an oil-soluble compound from telluric acid and organic diol. process utilises distillable chemicals that can be safely handled underground affords low radioactive backgrounds, optical absorption light yields...