High-spin states in 35S

Excited states in 35S were investigated by in-beam γ-ray spectroscopy using the 26Mg(18O, 2α1n) fusion-evaporation reaction The de-exciting γ-rays were measured with germanium detector arrays along with the measurement of evaporated charged particles in a 4π segmented Si detector array. The level scheme was extended up to 12470 keV. The obtained level structure is compared with the large-scale shell-model calculations. The possibility of isoscalar-pair excited states is discussed for J=(17/2) states with comparison between the experimental and theoretical results

High-spin states in 35^{35}S

International audienceExcited states in S35 were investigated by in-beam γ-ray spectroscopy using the Mg26(O18,2α1n) fusion-evaporation reaction. The deexciting γ rays were measured with germanium detector arrays along with the measurement of evaporated charged particles in a 4π-segmented Si detector array. The level scheme was extended up to 12.47 MeV. The obtained level structure is compared with the large-scale shell-model calculations. The possibility of isoscalar-pair excited states is discussed for J=(17/2) states with comparison between the experimental and theoretical results

How Different is the Core of 25^{25}F from 24^{24}Og.s._{g.s.}?

International audienceThe structure of a neutron-rich F25 nucleus is investigated by a quasifree (p,2p) knockout reaction at 270A  MeV in inverse kinematics. The sum of spectroscopic factors of π0d5/2 orbital is found to be 1.0±0.3. However, the spectroscopic factor with residual O24 nucleus being in the ground state is found to be only 0.36±0.13, while those in the excited state is 0.65±0.25. The result shows that the O24 core of F25 nucleus significantly differs from a free O24 nucleus, and the core consists of ∼35% O24g.s.. and ∼65% excited O24. The result may infer that the addition of the 0d5/2 proton considerably changes neutron structure in F25 from that in O24, which could be a possible mechanism responsible for the oxygen dripline anomaly

Candidate Resonant Tetraneutron State Populated by the He4(He8,Be8) Reaction

International audienceA candidate resonant tetraneutron state is found in the missing-mass spectrum obtained in the double-charge-exchange reaction He4(He8,Be8) at 186  MeV/u. The energy of the state is 0.83±0.65(stat)±1.25(syst)  MeV above the threshold of four-neutron decay with a significance level of 4.9σ. Utilizing the large positive Q value of the (He8,Be8) reaction, an almost recoilless condition of the four-neutron system was achieved so as to obtain a weakly interacting four-neutron system efficiently