Related papers: $\alpha$-particle condensate states in $^{16}$O
A new $\alpha$-cluster wave function is proposed which is of the $\alpha$-particle condensate type. Applications to $^{12}$C and $^{16}$O show that states of low density close to the 3 resp. 4 $\alpha$-particle threshold in both nuclei are…
In order to explore the 4 \alpha-particle condensate state in 16O, we solve a full four-body equation of motion based on the 4 \alpha OCM (Orthogonality Condition Model) in a large 4 \alpha model space spanned by Gaussian basis functions. A…
We show for the first time that the low-spin ($J \le 4^+$) six-$\alpha$ condensate candidate states in $^{24}$Mg, recently reported by Fujikawa et al. [Phys. Lett. B 848, 138384 (2024)], are well described by the superfluid $\alpha$-cluster…
Cluster structures and monopole transitions in positive parity states of $^{16}$O were investigated based on the generator coordinate method calculation of an extended $^{12}$C+$\alpha$ cluster model. The ground and excited states of a…
Inelastic $\alpha$ scattering on 16O is studied at 400 MeV by using an ice target. Near the 4-alpha breakup threshold of 14.4 MeV, a broad peak is observed at an excitation energy of 13.6+/-0.2 MeV with a width of 0.6+/-0.2 MeV. The…
Observed well-developed $\alpha$ cluster states in $^{16}$O, located above the four $\alpha$ threshold, are investigated from the viewpoint of Bose-Einstein condensation of $\alpha$ clusters by using a field-theoretical superfluid cluster…
The alpha cluster states of 16C are investigated by using the antisymmetrized molecular dynamics. It is shown that two different types of alpha cluster states exist: triangular and linear-chain states. The former has an approximate…
It is suggested that direct evidence of Bose-Einstein condensation of alpha particles is obtained by observing a phase mode (Nambu-Goldstone boson) with long wavelength even when characteristic features such as superfluidity is diffucult to…
We show that the five $\alpha$ cluster states recently observed in $^{20}$Ne, slightly above the five $\alpha$ threshold energy, are Bose-Einstein condensates of five $\alpha$ clusters. The states are described well using a superfluid…
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…
To clarify the effects of $\alpha$-cluster breaking on 3$\alpha$ cluster structures in $^{12}$C, we investigate $^{12}$C using a hybrid model that combines the Brink-Bloch cluster model with the $p_{3/2}$ subshell closure wave function. We…
Background: $\alpha+{^{12}{\rm C}}$ clustering in $^{16}{\rm O}$ has been of historical importance in nuclear clustering. In the last 15 years the $4\alpha$ condensate state has been proposed as a new-type cluster state. Purpose: The aim is…
The $\alpha$-bosonic properties such as single-$\alpha$ orbits and occupation numbers in $J^\pi$=$0^+$, $2^+$, $1^-$ and $3^-$ states of $^{12}$C around the $3\alpha$ threshold are investigated with the semi-microscopic $3\alpha$ cluster…
At low densities, with decreasing temperatures, in symmetric nuclear matter alpha-particles are formed, which eventually give raise to a quantum condensate with four-nucleon alpha-like correlations (quartetting). Starting with a model of…
We study 4$\alpha$ linear-chain states in 16O in comparison with 3$\alpha$ states in 12C by using the Generator Coordinate Method within a microscopic $N\alpha$-cluster model. It is shown to be very important to solve relative motion of…
The onset of quartetting, i.e. alpha-particle condensation, in symmetric nuclear matter is studied with the help of an in-medium modified four nucleon equation. It is found that at very low density quartetting wins over pairing, because of…
We present a new picture that the $\alpha$-linear-chain structure for ${^{12}{\rm C}}$ and ${^{16}{\rm O}}$ has one-dimensional $\alpha$ condensate character. The wave functions of linear-chain states which are described by superposing a…
The $\alpha$-particle condensate in nuclei is a novel state described by a product state of $\alpha$'s, all with their c.o.m. in the lowest 0S orbit. We demonstrate that a typical $\alpha$-particle condensate is the Hoyle state…
$\alpha$-cluster correlations in the ground states of $^{12}$C and $^{16}$O are studied. Because of the $\alpha$ correlations, the intrinsic states of $^{12}$C and $^{16}$O have triangle and tetrahedral shapes, respectively. The…
We have examined the hypothesis by Bijker and Iachello who asserted that 12C has an internal structure with three alpha particles arranged in a triangular shape, leading to the formation of the ground rotational band consisting of 0+, 2+,…