[en] Binomial and Poissonian models developed for calculating the counting efficiency from a free parameter is analysed in this paper. This model have been applied to liquid scintillator counting systems with two or three photomultipliers. It is mathematically demostrated that both models are equivalent and that the counting efficiencies calculated either from one or the other model are identical. (Author)

[en] In this paper, counting efficiency vs figure of merit for 19 electron capture radionuclides has been computed. Toluene based s c i n t i l l a t o r solution of 15 cm³ has been assumed in the computation. The relationships to obtain the probability per decay are given and the computed efficiency tabulated.(Author)

[en] In this work we present liquid scintillation counting efficiency tables for several radionuclides with single isomeric transitions, in which electron conversion and gamma emission processes are competitive. We study the radionuclides: ''58m CO, ''77mSE, ''79mBR,''87mSR,''89mY,''93mNB, ''103mRh, ''107mAG, ''109mAG,''113mXe; ''133mXe,''135mBa,''167mEr, for two different scintillators, Ultima-Gold and Insta-Gel. We consider volumes of and 15 mL for Ultima gold, and 15 mL for Insta-Gel. (Author)

[en] Counting efficiency formulae as a function of the non-detection probability and the electron distributions for systems with two, three or dour photomultipliers are obtained in this paper. It is assumed that the photocathode electron emission follows the Poisson distribution. The obtained formulae are basic to compute the counting efficiency in liquid scintillation spectrometers

[en] A new procedure to determine the activity of each mixture is described. The information contained in pulse height spectra is used. The dilatation, in the steps are essential to obtain a good experimental fitting. The procedure can be applied to mixtures by β''-, β''-, γ, β''+, β''+- γ, EC, Ec-γ and isomeric transitions. (Author) 10 refs

[en] Pairs of pulse height distribution curves, of C-14 samples, colour quenched and chemically quenched were obtained. The possibility to choose a counting window in order to obtain the counting efficiency curves, for both type of quenching was studied. (author). 7 figs., 7 refs

[en] A three L-subshells and K, M-shells atomic model is developed in order to obtain the counting efficiency in liquid scintillation counting. Mathematical expressions are given to calculate the probabilities of 264 different atomic rearrangement ways so as to determine corresponding effective energies. This new model will permit the testing of the influence of the different atomic and nuclear parameters upon the counting efficiency nuclides of low and medium atomic number decaying by electron capture. (author)

[en] In this paper three new statistical theorems are demonstrated and applied. These theorems simplify very much the obtention of the formulae to compute the counting efficiency when the detection system is formed by several photomultipliers associated in coincidence and sume. These theorems are applied to several photomultiplier arrangements in order to show their potential and the application. way

[en] We compute the liquid scintillation counting efficiency for 137Cs+137mBa and ''129 I taking into account the scintillator chemical composition. We consider the beta transition shape factors for the for bidden beta transitions of these nuclides, and the effects of 137mBa and 129mXe half-lives on the total counting efficiency. (Author) 8 refs

[en] A code, Scinfi, was developed, written in Basic, to compute the efficiency-quench standardization curve for any radionuclide. The program requires the standardization curve for ³H and the polynomial relations between counting efficiency and figure of merit for both ³H and the problem (e.g. ¹⁴C). The program is applied to the computation of the efficiency-quench standardization curve for ¹⁴C. Five different liquid scintillation spectrometers and two scintillator solutions have been checked. The computation results are compared with the experimental values obtained with a set of ¹⁴C standardized samples. (author)