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The motivation of the diagonalization method is to take into consideration the coupling between closed and opened channels in term of perturbation theory and to neglect the indirect coupling as well but also the autoionisation states through the opened channels. This procedure leads to a relatively simple mathematical problem consisting of solving a system of linear algebraic equations instead of a system of coupled differential equations or integro-differential equations. In this paper, we will focus on the Resonance positions, Partial and total widths for the autoionization into various decay channels of some 1,3 L° doubly excited states of helium-like oxygen ion O 6+ converging on the N=5 hydrogenic thresholds are reported for L=1, 2, 3, 4, 5, 6 and 7. The calculation was made in the framework of the diagonalization method approximation in LS coupling scheme. The partial widths for multi-channel autoionizing levels to sublevels of O 7+ are calculated by neglecting the direct coupling between the open channels. We were able to find results consistent with some in the literature. It is about the configuration P, D, F, G, H, I and K. We could see that the decays are relatively dependent on the ionization thresholds of the residual ion O 7+ . Some analyses are made on these resultast and only according to the level of decay focused in this paper then made a surplus in the framework of nuclear spectroscopy.

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An inaccurate quantification of the reference level of background radiation introduces an inherent statistical bias. Thus, it is necessary to develop a flexible and easy method for accurate characterization of naturally occurring radionuclides (NOR) reference background level in the mining area. In this paper, we propose the use of Bayesian modeling as an alternative statistics technique to study the spatial distribution of NOR. The Markov chain Monte Carlo (MCMC) approach is used to infer the statistical parameter of naturally occurring gammainduced radionuclides such as 232 Th, 40 K and 228 Ra. We used a bootstrapping method to obtain an accurate sub-sample and then exclude all potential outliers which are out of the Highest Density Interval (HDI). With the resampled sample, we build a model with a Bayesian statistics method with MCMC to draw an inference of the posterior distribution of the gamma-induced radionuclides.

Studies on the fallout of radionuclides using 137Cs as tracers which allows to estimate the rates of erosion and soil deposition was conducted. In this study, the reference inventory used was 414.27±71.21Bq m -2 which is the value obtained in the regional African technical projects RAF 5075 funded by the IAEA. The conversion of inventory into erosion and deposition rates we have used MODERN. The new model MODERN (Modelling Deposition and Erosion rates with RadioNuclides) considers the precise depth distribution of any FRN at the reference site and allows adapting it for any specific site conditions. With MODERN the results show the erosion rate is 7.2t ha -1 yr -1 , then with the conversion model: « Mass Balance model II » (MBMII) the erosion rates level varies between 1.3 to 43.0t. ha -1 . Year -1 . The deposition rate assessed at the study site level with MODERN is in the range 7.4 to 8.1t ha -1 year -1 and varies between 8.54 to 45.68t ha -1 year -1 with MBMII.