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A new routine method to measure 227Ac in water samples was developed. Actinium-227 was separated from potential radioactive and matrix interferences using a DGA resin (Eichrom) at optimal extraction and elution conditions (2 M and 15.7 M HNO3, respectively). This was possible because Ac was pre-concentrated and separated from Ca using titanium phosphate co-precipitation at pH 3.5. Finally, 227Ac was counted by alpha spectrometry for 48 h after a cerium fluoride micro-precipitation. A minimal detection limit of 0.03 ± 0.01 Bq l−1 was obtained. The method was validated using spiked water samples. [ABSTRACT FROM AUTHOR]

The experimental achievements and the results obtained so far with the LPCTrap device installed at GANIL are presented. The apparatus is dedicated to the study of the weak interaction at low energy by means of precise measurements of the β − ν angular correlation parameter in nuclear β decays. So far, the data collected with three isotopes have enabled to determine, for the first time, the charge state distributions of the recoiling ions, induced by shakeoff process. The analysis is presently refined to deduce the correlation parameters, with the potential of improving both the constraint deduced at low energy on exotic tensor currents (He) and the precision on the V element of the quark-mixing matrix (Ar and Ne) deduced from the mirror transitions dataset. [ABSTRACT FROM AUTHOR]

The LPCTrap setup is a sensitive tool to measure the β − ν angular correlation coefficient, a, which can yield the mixing ratio ρ of a β decay transition. The latter enables the extraction of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element V. In such a measurement, the most relevant observable is the energy distribution of the recoiling daughter nuclei following the nuclear β decay, which is obtained using a time-of-flight technique. In order to maximize the precision, one can reduce the systematic errors through a thorough simulation of the whole set-up, especially with a correct model of the trapped ion cloud. This paper presents such a simulation package and focuses on the ion cloud features; particular attention is therefore paid to realistic descriptions of trapping field dynamics, buffer gas cooling and the N-body space charge effects. [ABSTRACT FROM AUTHOR]