Reaction cross section measurements of neutron-rich exotic nuclei in the vicinity of closed shells N=20 and N=28

Mesures de section efficace de réaction de noyaux exotiques riches en neutrons dans la zone de fermeture des couches N=20 et N=28

Abdenbi Khouaja (1)

1 GANIL - Grand Accélérateur National d'Ions Lourds

Using the direct method, the mean energy integrated reaction cross section was investigated for a wide range of neutron-rich nuclei (N → Ar) at GANIL. Using the parametrisation of S. Kox, 19 new radii measurements (reaction cross sections) were obtained. By the isotopic, isotonic and isospin dependence, the evolution of the strong reduced radius was studied according to the excess of neutrons. New halo effect is proposed to the nuclei of Mg35 and S44. A quadratic parametrization is also proposed for the nuclear radius as a function of the isospin in the region of closed shells N=8 and N=28. In addition, we used a modified version of the Glauber model for studying the tail and matter distribution of nuclei. Indeed, using our new data the effects of the nuclear size (root mean square radii) and the matter distribution (diffusivity) were de-convoluted for each isotope. The root mean square radii of Na and Mg isotopes obtained so far were consistent with the ones from literature.

Nous présentons des mesures de section efficace de réaction, obtenues par la technique directe pour des dizaines de noyaux riches en neutrons (N

Mots clés: Nuclear structure

Mots clés: Structure nucléaire; Modèles nucléaires; Section efficace de réaction; Spectromètres magnétiques; Distribution de matière; Détection de rayonnement

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

Abdenbi Khouaja. Mesures de section efficace de réaction de noyaux exotiques riches en neutrons dans la zone de fermeture des couches N=20 et N=28. Physique Nucléaire Expérimentale [nucl-ex]. Université de Caen, 2003. Français. ⟨NNT : ⟩. ⟨tel-00005507⟩