Precise half-life measurements for 38Ca and 39Ca

Bertram Blank (1) , A. Bey , I. Matea , J. Souin (1) , L. Audirac (1) , M.J.G. Borge (2) , G. Canchel (1) , P. Delahaye (3) , F. Delalee (1) , C.-E. Demonchy (1) , R. Domínguez-Reyes (2) , L.M. Fraile , J. Giovinazzo (1) , Tran Trong Hui , J. Huikari , D. Lunney (4) , F. Munoz (1) , J.-L. Pedroza (1) , C. Plaisir (1) , L. Serani (1) , S. Sturm , O. Tengblad (2) , F. Wenander (3)

1 CENBG - Centre d'Etudes Nucléaires de Bordeaux Gradignan
2 IEM - Instituto de Estructura de la Materia
3 CERN - European Organization for Nuclear Research
4 CSNSM - Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse

The half-lives of 38Ca and 39Ca have been measured at ISOLDE of CERN. The REXTRAP facility was used to prepare ultra-clean samples of radioactive nuclei for precision decay spectroscopy. 38Ca is one of the T z = - 1 , 0+ 0+ -emitting nuclides used to determine the vector coupling constant of the weak interaction and the Vud quark-mixing matrix element. The result obtained, T 1/2 = 443.8(19) ms, is four times more precise than the average of previous measurements. For 39Ca , a half-life of T 1/2 = 860.7(10) ms is obtained, a result in agreement with the average value from the literature.

Mots clés: POSITRON DECAYS; NUCLEI; SPECTROSCOPY; LIVES; IONS

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

Bertram Blank, A. Bey, I. Matea, J. Souin, L. Audirac, et al.. Precise half-life measurements for 38Ca and 39Ca. European Physical Journal A, 2010, 44, pp.363-372. ⟨10.1140/epja/i2010-10958-2⟩. ⟨in2p3-00496004⟩