The N = 16 spherical shell closure in 24O

K. Tshoo , Y. Satou , H. Bhang , S. Choi , T. Nakamura , Y. Kondo , S. Deguchi , Y. Kawada , N. Kobayashi (1) , Y. Nakayama , K. N. Tanaka , N. Tanaka , N. Aoi , M. Ishihara , T. Motobayashi , H. Otsu , H. Sakurai , S. Takeuchi , Y. Togano , K. Yoneda , Z. H. Li , F. Delaunay (2) , J. Gibelin (3) , F.M. Marqués (3) , N.A. Orr (3) , T. Honda , M. Matsushita , T. Kobayashi (4) , Y. Miyashita , T. Sumikama , K. Yoshinaga , S. Shimoura , D. Sohler (5) , T. Zheng , Z. X. Cao

1 Department of Physics [Tokyo]
2 IBV - Institut de Biologie Valrose
3 LPCC - Laboratoire de physique corpusculaire de Caen
4 Department of Physics [Sendai]
5 ATOMKI - Institute for Nuclear Research [Budapest]

The unbound excited states of the neutron drip-line isotope 24O have been investigated via the 24O(p,p')23O+n reaction in inverse kinematics at a beam energy of 62 MeV/nucleon. The decay energy spectrum of 24O* was reconstructed from the momenta of 23O and the neutron. The spin-parity of the first excited state, observed at Ex = 4.65 +/- 0.14 MeV, was determined to be Jpi = 2+ from the angular distribution of the cross section. Higher lying states were also observed. The quadrupole transition parameter beta2 of the 2+ state was deduced, for the first time, to be 0.15 +/- 0.04. The relatively high excitation energy and small beta2 value are indicative of the N = 16 shell closure in 24O.

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

K. Tshoo, Y. Satou, H. Bhang, S. Choi, T. Nakamura, et al.. The N = 16 spherical shell closure in 24O. 5th Asia-Pacific Conference on Few-Body Problems in Physics, Seoul 2011, 2011, Séoul, South Korea. pp.459-463, ⟨10.1007/s00601-012-0413-3⟩. ⟨in2p3-00785481⟩