相关论文: Ab initio calculation of the Hoyle state
Carbon is produced during the helium burning phase of sufficiently massive stars through the triple alpha process. The $0^+$ energy level of the carbon nucleus allows for resonant nuclear reactions, which act to greatly increase the carbon…
The process of carbon burning is vital to understanding late stage stellar evolution of massive stars and the conditions of certain supernovae. Carbon burning is a complex problem, involving quantum tunnelling and nuclear molecular states.…
The spatial structure of the lowest 0$_1^+$, 0$_2^+$, 2$_1^+$ and 2$_2^+$ states of the $^{12}$C nucleus is studied within the 3$\alpha$ model with the Buck, Friedrich, and Wheatley $\alpha \alpha$ potential with Pauli forbidden states in…
Through the triple-alpha process practically all of the carbon in our universe is synthesized as the ash of helium burning in red giants. The triple-alpha process proceeds trough the ground state of 8Be and though the 02+-state in 12C. We…
The partcle-induced hadronic de-excitation of the Hoyle state in $^{12}$C induced by inelastic scattering in a hot and dense plasma can enhance the triple-alpha reaction rate. This prevents the production of heavy nuclei within the…
The Hoyle state and other resonances in the continuum above the 3 alpha threshold in 12C are studied in a microscopic cluster model. Whereas the Hoyle state is a very sharp resonance and can be treated reasonably well in bound state…
The energy levels of the first few low-lying states of carbon in intense magnetic fields upwards of $\approx 10^7$ T are calculated in this study. We extend our previously employed pseudospectral approach for calculating the eigenstates of…
In stellar core-collapse events matter is heated and compressed to densities above nuclear matter saturation density. For progenitors stars with masses above about 25 solar masses, which eventually form a black hole, the temperatures and…
The fragmentation of quasi-projectiles from the nuclear reaction $^{40}$Ca+$^{12}$C at 25 MeV/nucleon was used to produce excited states candidates to $\alpha$-particle condensation. Complete kinematic characterization of individual decay…
Population III stars are the first stars in the Universe to form at z=20-30 out of a pure hydrogen and helium gas in minihalos of 10^5-10^6 M$_\odot$ . Cooling and fragmentation is thus regulated via molecular hydrogen. At densities above…
Although carbon monoxide (CO) is an abundant molecule and may have great importance for planetary interiors, measurements of its properties are difficult due to its extreme volatility. We calculate the equation of state for CO over a range…
How do protons and neutrons bind to form nuclei? This is the central question of ab initio nuclear structure theory. While the answer may seem as simple as the fact that nuclear forces are attractive, the full story is more complex and…
The ${}^{12}\mathrm{C}/{}^{13}\mathrm{C}$ ratio is a significant indicator of nucleosynthesis and mixing processes during hydrogen burning in stars. Its value mainly depends on the relative rates of the…
We investigate resonance states in three-cluster continuum of some light nuclei $^{9}$Be, $^{9}$B, $^{10}$B, $^{11}$B and $^{11}$C. These nuclei are considered to have a three-cluster configuration consisting of two alpha-particles and…
We present a detailed discussion of the structure of the low-lying positive-parity energy spectrum of $^{12}$C from a no-core shell-model perspective. The approach utilizes a fraction of the usual shell-model space and extends its…
We describe the excited 0+ state of 12C at 7.654 MeV, often called the Hoyle state, in terms of a local potential 8Be+alpha cluster model. We use a previously published prescription for the cluster-core potential to solve the Schroedinger…
The algebraic molecular model is used in $^{12}$C to construct densities and transition densities connecting low-lying states of the rotovibrational spectrum, first and foremost those belonging to the rotational bands based on the ground…
We develop a novel formulation of the hadron-resonance gas model which, besides a hard-core repulsion, explicitly accounts for the surface tension induced by the interaction between the particles. Such an equation of state allows us to go…
We present lattice calculations of the low-lying spectrum of $^{12}$C using a simple nucleon-nucleon interaction that is independent of spin and isospin and therefore invariant under Wigner's SU(4) symmetry. We find strong signals for all…
We investigate geometric configurations of $\alpha$ ($^4$He nucleus) clusters in the second $J^\pi=2^+$ state of $^{12}$C, which has been discussed as a rotational band member of the second $0^+$ state, the Hoyle state. The ground and…