相关论文: Structure and rotations of the Hoyle state
The Semimicroscopic Algebraic Cluster Model (SACM) is applied to 12C as a system of three alpha- clusters. The microscopic model space, which observes the Pauli-Exclusion-Principle (PEP), is constructed. It is shown that the 12C nucleus can…
The $\alpha$ condensation in the ${}^{12}C$, ${}^{16}O$ and ${}^{20}Ne$ nuclei is investigated within an analytical solvable model. It is found that the calculated ratio of the ground state energies of the Hoyle state of ${}^{12}C$ and the…
The Hoyle state plays a crucial role in the helium burning of stars that have reached the red giant stage. The close proximity of this state to the triple-alpha threshold is needed for the production of carbon, oxygen, and other elements…
It is shown that the rotational band structure of the cluster states in 12C and 16O can be understood in terms of the underlying discrete symmetry that characterizes the geometrical configuration of the alpha-particles, i.e. an equilateral…
Studies of the 16O(9Be,alpha7Be)14C and 7Li(9Be,alpha7Li)5He reactions at E{beam}=70 MeV have been performed using resonant particle spectroscopy techniques. The 11C excited states decaying into alpha+7Be(gs) are observed at 8.65, 9.85,…
Nuclear clustering describes the appearance of structures resembling smaller nuclei such as alpha particles (4He nuclei) within the interior of a larger nucleus. While clustering is important for several well-known examples, much remains to…
Angular distributions for elastic and inelastic scattering of $^3$He from $^{12}$C were measured at energies 50.5 and 60 MeV. The Airy minimum of the prerainbow scattering was clearly observed in the angular distributions for the 0$_2^+$…
Two-state cooperativity is an important characteristic in protein folding. It is defined by a depletion of states lying energetically between folded and unfolded conformations. While there are different ways to test for two-state…
Magnetic systems are fertile ground for the emergence of exotic states when the magnetic interactions cannot be satisfied simultaneously due to the topology of the lattice - a situation known as geometrical frustration. Spinels, AB2O4, can…
In this article we review the present status of alpha clustering in nuclear systems. First of all, an important aspect is condensation in nuclear matter. Second, the alpha container model, recently been proposed by…
The fusion of $\alpha$ and $^8$Be to produce a $^{12}$C nucleus is a crucial process in nucleosynthesis. In the laboratory, this process can only be studied theoretically as a $^8$Be target or projectile cannot be prepared experimentally.…
Certain aspects of the recently proposed antisymmetrised alpha particle product state wave function, or THSR alpha cluster wave function, for the description of the ground state in 8Be, the Hoyle state in 12C, and analogous states in…
Densities and transition densities are computed in an equilateral triangular alpha-cluster model for $^{12}$C, in which each $\alpha$ particle is taken as a gaussian density distribution. The ground-state, the symmetric vibration (Hoyle…
We present a microscopic dynamical study of the reactions involving three $^{4}$He clusters. We show that the much discussed triple-$\alpha$ linear chain configuration of $^{12}$C is formed with a certain lifetime and subsequently decays…
Nucleonic matter displays a quantum liquid structure, but in some cases finite nuclei behave like molecules composed of clusters of protons and neutrons. Clustering is a recurrent feature in light nuclei, from beryllium to nickel. For…
Electromagnetic transitions from deformed structures based on $\alpha$ configurations or on heavier clusters are discussed, drawing the link between multiparticle-multihole excited bands and cluster structures. Enhanced E2 and E1…
Multi-center (molecular) structures can play an important role in light nuclei. The highly deformed rotational band in 10Be with band head at 6.179 MeV has been observed recently and suggested to have an exotic alpha:2n:alpha configuration.…
We employ the constrained density functional theory to investigate cluster phenomena for the $^{12}$C nucleus. The proton and neutron densities are generated from the placement of three $^{4}$He nuclei (alpha particles) geometrically. These…
There is a deep astrophysical interest in the structure of $^{19}$F states close to the alpha decay threshold. The nuclear structure of these states is important for understanding of the development of $\alpha$ clustering in the $^{20}$Ne…
The structure of the second 0^+ state of ^{10}Be is investigated using a microscopic $\alpha+\alpha+n+n$ model based on the molecular-orbit (MO) model. The second 0^+ state, which has dominantly the (1/2^+)^2 configuration, is shown to have…