Study of N = 16 for Ne isotopes

²⁷Ne has been investigated through the one neutron transfer reaction ²⁶Ne(d,p)²⁷Ne in inverse kinematics at 9.7 MeV/nucleon. The results support the existence of a low lying negative parity state in ²⁷Ne which is a signature of a reduced sd-fp shell gap in the N = 16 neutron rich region, at variance with stable nuclei.     

A weight-function approach for determining watershed initial conditions for combustion waves

In many generic combustion models, one finds that a combustionwave will develop with a specific wave speed. However, thereare possible initial temperature profiles which do not evolveinto such waves, but rather die out to the ambient temperature.There can exist, in some models, a clear distinction betweenthose initial conditions that do evolve into combustion wavesand those that do not; this is sometimes referred to as thewatershed initial condition. When fuel consumption is consideredto be negligible, analytical methods can be used to obtain theexact watershed. In this paper, we consider the problem of determiningpseudo-watersheds and ascertaining the relationship betweenthese pseudo-watersheds and the exact watersheds. In the processa novel weight-function approach for infinite spatial domainsis developed.     

丰中子核63,65,67Mn的在束γ谱学研究

利用放射性束68Fe轰击液氢靶引起的敲出反应,研究了极端丰中子核63,65,67Mn的激发态,指认了它们的自旋宇称,建立了这三个原子核的能级纲图。纲图包含11/2–、9/2–和 7/2– 三个激发态以及$5/2_{\rm{g.s.}}^{-}$基态,它们由三条$\Delta I \!=\! 1$的$\gamma$跃迁连接。这种能级结构与$K \!=\! 5/2$时强耦合转动带的特征一致。使用改进的LNPS有效相互作用(LNPSm)的大规模壳模型计算能很好地重现观测到的能级。计算表明,65,67Mn的低位激发态都主要包含处于$4p{\text -}4h$的中子组态和$1p{\text -}1h$的质子组态。基于实验结果发现,在吸积中子星壳中,与质量数$A \!=\! 63$相关的Urca中微子冷却效果比预期的要强很多,而$A \!=\! 65, 67$的冷却效果比预期的更弱。     

Synthesis of cytotoxic cyanobactin,Wewakazole B

We report herein the synthesis of cytotoxic cyanobactin, Wewakazole B through an efficient solution-phase approach. The key steps of the synthesis are the macrocyclic lactamization of linear dodecapeptide and construction of two hexapeptides with three different substituted oxazole rings.     

Shape coexistence in light se isotopes: evidence for oblate shapes

Lifetimes of states in the ground-state bands of (70)Se and (72)Se were measured using the recoil-distance Doppler shift method. The results deviate significantly from earlier measurements, requiring a revision of the conclusions drawn from a recent Coulomb excitation experiment concerning the shape of (70)Se. The new results lead to a coherent picture of shape coexistence in the neutron-deficient selenium and krypton isotopes. The coexistence and evolution of oblate and prolate shapes in this mass region is for the first time consistently described by new Hartree-Fock-Bogolyubov-based configuration-mixing calculations which were performed using the Gogny D1S interaction.     

Hydrogen targets for exotic-nuclei studies developed over the past 10 years

Hydrogen-induced reactions provide essential information on nuclear structure, complementary to other experimental probes. For studies at both low and relativistic incident energy, developments in hydrogen targets have been performed over the past 10 years in parallel with the development of new radioactive beams. We present a review of all major hydrogen target developments related to the study of exotic nuclei with direct reactions in inverse kinematics. Both polarized and non-polarized systems are presented.     

First measurement of the giant monopole and quadrupole resonances in a short-lived nucleus: 56Ni

The isoscalar giant monopole resonance (GMR) and giant quadrupole resonance (GQR) have been measured in the 56Ni unstable nucleus by inducing the 56Ni(d,d') reaction at 50A MeV in the Maya active target at the GANIL facility. The GMR and GQR centroids are measured at 19.3+/-0.5 MeV and 16.2+/-0.5 MeV, respectively. The corresponding angular distributions are extracted from 3 degrees to 7 degrees . A multipole decomposition analysis using distorted wave Born approximation with random phase approximation transition densities shows that both the GMR and the GQR exhaust a large fraction of the energy-weighted sum rule. The demonstration of this new method opens a broad range of giant resonance studies at intermediate-energy radioactive beam facilities.