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This study explores the age-old quest to construct a geometric model of a quantum particle. While static classical particle models have largely been dismissed, the focus has now shifted to intricate dynamic models that hold the promise of reconciling general relativity with quantum mechanics. We propose that matter particles can be described as radiation confined within dynamically curved spacetime regions, without the need for quantization of space and time, and using standard field equations and natural Planck units. Specifically, we investigate a cyclic or oscillating radiation-dominated micro-cosmos undergoing repeated bouncing. Our methodology employs integration, with carefully defined initial conditions. The results include several observable properties characteristic of quantum particles. We calculate the total mass, revealing a compelling inverse proportionality between mass and radius identical with the de Broglie relationship. Applying this model to protons, we discover a profound and surprisingly simple relationship between the proton’s radius and mass expressed in Planck units. This enables a definition of the proton radius that aligns remarkably well with the 2018 CODATA value. Furthermore, our analysis demonstrates that the radial density profile of the proton (or nucleon), averaged over a cycle time, increases toward the center. The problem of embedding the micro-cosmos within a background spacetime is also described. These results underscore the relevance of general relativity in the domain of nuclear physics. Moreover, the model offers a fresh perspective that can stimulate new ideas in the ongoing quest to unify general relativity with quantum physics.

The differential cross-sections for elastic ¹²C–¹²C scattering at 2400 and 1449 MeV are calculated on the basis of the multiple diffraction scattering theory and α-cluster model with dispersion. At the energy 2400 MeV the calculations were performed by means of "effective" and "free" α–α amplitudes. It is shown that the results obtained differ significantly.

Symmetry energy coefficients of explicitly isospin asymmetric nuclear matter at variable densities (from 0.5ρ₀ up to 2ρ₀) are studied as generalized screening functions. An extended stability condition for asymmetric nuclear matter is proposed. We find the possibility of obtaining stable asymmetric nuclear matter even in some cases for which the symmetric nuclear matter limit is unstable. Skyrme-type forces are extensively used in analytical expressions of the symmetry energy coefficients derived as generalized screening functions in the four channels of the particle hole interaction producing alternative behaviors at different ρ and b (respectively, the density and the asymmetry coefficient). The spin and spin-isospin coefficients, with corrections to the usual Landau Migdal parameters, indicate the possibility of occurring instabilities with common features depending on the nuclear density and n–p asymmetry. Possible relevance for high energy heavy ions collisions and astrophysical objects is discussed.

Working within the framework of relativistic mean field theory, we study for the first time the clustering structure (nuclear sub-structure) of ^112–122Ba nuclei in an axially deformed cylindrical coordinate. We calculate the individual neutrons and protons density distributions for Ba-isotopes. From the analysis of the clustering configurations in total (neutrons-plus-protons) density distributions for various shapes of both the ground and excited states, we find different sub-structures inside the Ba nuclei considered here. The important step, carried out here for the first time, is the counting of number of protons and neutrons present in the clustering region(s). ¹²C is shown to constitute the cluster configuration in prolate-deformed ground-states of ^112–116Ba and oblate-deformed first excited states of ^118–122Ba nuclei. Presence of other lighter clusters such as ²H, ³H and nuclei in the neighborhood of N = Z, ¹⁴N, ^34–36Cl, ³⁶Ar and ⁴²Ca are also indicated in the ground and excited states of these nuclei. Cases with no cluster configuration are shown for ^112–116Ba in their first and second excited states. All these results are of interest for the observed intermediate-mass-fragments and fusion–fission processes, and the so far unobserved evaporation residues from the decaying Ba* compound nuclei formed in heavy ion reactions.

We study the binding energy, root-mean-square radius and quadrupole deformation parameter for the synthesized superheavy element Z = 115, within the formalism of relativistic mean field theory. The calculation is dones for various isotopes of Z = 115 element, starting from A = 272 to A = 292. A systematic comparison between the binding energies and experimental data is made.The calculated binding energies are in good agreement with experimental result. The results show the prolate deformation for the ground state of these nuclei. The most stable isotope is found to be ²⁸²115 nucleus (N = 167) in the isotopic chain. We have also studied Q_α and T_α for the α-decay chains of ^{287, 288}115.

In this paper, we study a phenomenological collective model for the calculation of the nuclear density and ground state binding energy of nuclei. The proton density is assumed proportional to the nuclear density. The total binding energy of the nuclear matter consists of the binding energy of infinite nuclear matter, of two Yukawa-potentials, of the Coulomb-energy and of the symmetry-energy. The parameters of the Yukawa-potential are fitted with the Bethe–Weizsäcker (BW) mass formula. The resulting binding energies and nuclear densities agree quite satisfying with known nuclear values.

We briefly introduce the newly proposed probe to the neutron and proton chemical potential (and density) difference, which is called as the isobaric yield ratio difference (IBD). The IBD probe is related to the chemical potential difference of neutrons and protons between two reactions, at the same time, the nuclear density difference between two reactions. The relationship between the IBD probe and the isoscaling method has also been discussed.

Suppose that neutron star core be composed by degenerate neutrons, protons and electrons above nuclear density. Applying theWeizsacker mass formula for the nuclear potential energy of neutron star cores, we integrate Einstein-Maxwell equation with electro and β- equilibrium to obtain the radial distributions of baryon and electron densities in the global neutrality condition. It is shown that at nuclear density baryon densities sharply go to zero in a few fermi, while the electron density well extends to a few hundred Compton lengths, as results a strong electric field is developed in the core surface-shell of thickness of a few fermi.