759 articles – 7540 Notices  [english version]
 HAL : in2p3-00025993, version 1
 2nd International Conference on Nuclear Physics in Astrophysics, Debrecen : Hongrie
 Study of the N = 28 shell closure in the Ar isotopic chain A SPIRAL experiment for nuclear astrophysics
 SPIRAL Collaboration(s)
 (2006)
 The structure of the neutron-rich nucleus $^{47}$Ar has been investigated through the d( $^{46)$Ar, $^{47)$Ar)p transfer reaction. The radioactive beam of $^{46}$Ar at 10A·MeV was provided by the SPIRAL facility at GANIL. The protons corresponding to a neutron pick-up on bound or unbound states mechanism in $^{47}$Ar nuclei were detected at backward angles by the position-sensitive Si array-detector MUST. The transfer-like ejectiles were detected in the SPEG spectrometer. Level scheme, spin assignments and spectroscopic factors have been deduced for $^{47}$Ar and compared to shell model predictions. They suggest a slight erosion of the N = 28 shell gap from the weakening of the spin-orbit interaction arising from the f and p orbitals. These spectroscopic information are subsequently used to infer (n,$\gamma$) reaction rates in the Ar isotopic chain to understand the origin of the $^{48}$Ca/ $^{46}$Ca abnormal isotopic ratio observed in certain inclusions of meteorites.
 Thème(s) : Physique/Physique Nucléaire Expérimentale
 Mot(s)-clé(s) : Spin – parity – and isobaric spin – Spectroscopic factors – Transfer reactions – Nucleosynthesis in novae – supernovae and other explosive environments
 in2p3-00025993, version 1 http://hal.in2p3.fr/in2p3-00025993 oai:hal.in2p3.fr:in2p3-00025993 Contributeur : Michel Lion <> Soumis le : Mercredi 26 Avril 2006, 10:33:06 Dernière modification le : Mardi 10 Juillet 2007, 17:01:34