0000000000281538
AUTHOR
J. C. Angélique
Radioactivity of neutron-rich oxygen fluorine and neon isotopes
The $\ensuremath{\gamma}$ radiation and neutrons emitted following the $\ensuremath{\beta}$ decays of ${}^{24}\mathrm{O},$ ${}^{25--27}\mathrm{F},$ and ${}^{28\ensuremath{-}30}\mathrm{Ne}$ have been measured. The nuclides were produced in the quasifragmentation of a 2.8 GeV ${}^{36}\mathrm{S}$ beam, separated in-flight and identified through time-of-flight and energy-loss measurements. The ions were stopped in a silicon detector telescope, which was used to detect the $\ensuremath{\beta}$ particles emitted in their subsequent radioactive decay. The coincident $\ensuremath{\gamma}$ rays were measured using four large volume germanium detectors mounted close to the implantation point and the …
New region of deformation in the neutron-rich 60 24Cr36 and 62 24Cr38
The neutron-rich nuclei 23 60-63V have been produced at GANIL via interactions of a 61.8A·MeV 76Ge beam with a 58Ni target. Beta-decay to 24 60-63Cr has been investigated using combined β- and γ-ray spectroscopy. Half-lives of the 60-63V nuclei have been determined, and the existence of a beta-decay isomer in the 60V nucleus is strongly supported. The observation of low-energy 2+ states in 60Cr (646keV) and 62Cr (446keV) suggests that these isotopes are strongly deformed with β2 ∼ 0.3. This is confirmed by shell model calculations which show the dominant influence of the intruder g and d orbitals to obtain low 2+ energies in the neutron-rich Cr isotopes.
Beta-decay half-lives at the N = 28 shell closure
Abstract Measurements of the beta-decay half-lives of neutron-rich nuclei (MgAr) in the vicinity of the N =28 shell closure are reported. Some 22 half-lives have been determined, 12 of which for the first time. Particular emphasis is placed on the results for the Si isotopes, the half-lives of which have been extended from N =25 to 28. Comparison with QRPA calculations suggests that 42 Si is strongly deformed. This is discussed in the light of a possible weakening of the spin–orbit potential.
Beta decay studies of neutron-rich $_{21}$Sc-$_{27}$Co nuclei at GANIL
Abstract The neutron-rich nuclei 2157,58Sc, 2258–60Ti, 2258–60Ti, 2360–62V, 2464–66Cr, 2564–68Mn, 2667–70Fe and 2769–71Co have been produced at Ganil via interactions of a 61.8 A.MeV 76Ge beam with a 58Ni target. Beta-decay studies have been achieved, bringing new half-lives and a better nuclear structure knowledge in this region. These results could help for understanding the overabundances of the neutron-rich stable 58Fe, 64Ni in certain inclusions of meteorites.