Related papers: Decay and structure of the Hoyle state
Background: Two new $J^\pi=0^+$ states are recently observed around a few MeV above the Hoyle state (the second $0^+$ state in 12C). The characters of them are only poorly discussed in theory and are still mysterious. Purpose: I give for…
The $0^{+}$ states of $^{12}\mathrm{C}$ are considered within the framework of the microscopic three-$\alpha$-cluster model. The main attention is paid to accurate calculation of the width of the extremely narrow near-threshold $0^+_2$…
We address the problem of calculating momentum distributions of particles emerging from the three-body decay of a many-body resonance. We show that these distributions are determined by the asymptotics of the coordinate-space complex-energy…
We present a theoretical framework for calculating the asymptotic properties and decay dynamics of three-body resonances described in a discrete basis. The method involves solving an inhomogeneous Schr\"odinger equation to determine the…
We have analyzed $^{3}$He scattering from $^{12}$C at 34.7 and 72 MeV in a coupled channel method with a double folding potential derived from the precise wave functions for the ground 0$^+$ state and $0_2^+$ (7.65 MeV) Hoyle state, which…
We discuss the three-body decay mechanisms of many-body resonances. R-matrix sequential description is compared with full Faddeev computation. The role of the angular momentum and boson symmetries is also studied. As an illustration we show…
The $^{12}$C nucleus with $N$=6 and $Z$=6 is a doubly closed-shell nucleus in a toroidal potential. In the description of the ground state and the Hoyle state of $^{12}$C in the resonating group method or the generator coordinate method, a…
Background: A recent inelastic alpha-scattering experiment [Phys. Rev. Lett. 129, 102701 (2022)] found $0^+$ resonances in $^{24}$Mg on and above the $^{12}$C+$^{12}$C break-up threshold. It has been conjectured that the states have a…
Recently, the triple-\alpha (3\alpha) process, by which three 4He nuclei are fused into a 12C nucleus in stars, was studied by different methods in solving the quantum mechanical three-body problem. Their results of the thermonuclear…
The electric quadrupole transitions between $0^+$, $2^+$, and $4^+$ states in $^{12}$C are investigated in a $3\alpha$ model. The three-body wave functions are obtained by means of the hyperspherical adiabatic expansion method, and the…
Knowledge of the low-lying monopole strength in $\mathrm{^{12}C}$, the Hoyle state in particular, is crucial for our understanding of both the astrophysically important $3\alpha$ reaction and of $\alpha$-particle clustering. The…
The $^9$C nucleus and related capture reaction, ${^8\mathrm{B}}(p,\gamma){^9\mathrm{C}}$, have been intensively studied with an astrophysical interest. Due to the weakly-bound nature of $^9$C, its structure is likely to be described as the…
The 3$\alpha$ decay of the 16.62\,MeV (2$^-$, T=1) resonance in $^{12}$C has been studied for nearly a century starting with one of the first nuclear reaction studies at the Cavendish Laboratory in the 1930s. In the hitherto latest study…
The existence of the $0_3^+$ and $0_4^+$ states around 10 MeV excitation energy in ${^{12}{\rm C}}$ is confirmed by a fully microscopic 3$\alpha$ cluster model. Firstly, a GCM (generator coordinate method) calculation is performed by…
The first excited $J^\pi=0^+$ state of $^{12}$C, the so-called Hoyle state, plays an essential role in a triple-$\alpha$ ($^4$He) reaction, which is a main contributor to the synthesis of $^{12}$C in a burning star. We investigate the…
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$_2^+$…
The hyperspherical adiabatic expansion is combined with complex scaling and used to calculate low-lying nuclear resonances of $^{12}$C in the $3\alpha$-model. We use Ali-Bodmer potentials and compare results for other potentials…
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…
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,…
A study of the 7Li(9Be,4He9Be)3H reaction at E{beam}=70 MeV has been performed using resonant particle spectroscopy techniques and provides a measurement of alpha-decaying states in 13C. Excited states are observed at 12.0, 13.4, 14.1,…