相关论文: Centrifugal effects in N-Delta states
This talk focuses on a recent work aiming at determining the composition of certain $N^*$ and $\Delta$ resonances, i.e. whether they are compact states formed directly by quarks and gluons, or composite generated from the meson-baryon…
In this talk, we present a new interpretation for the recently observed $\Xi(1820)$ resonance. We recall that the chiral unitary approach for the interaction of pseudoscalar mesons with the baryons of the decuplet predicts two states for…
We study the properties of a D-brane in the presence of $k$ NS5 branes. The Dirac-Born-Infeld action describing the dynamics of this D-brane is very similar to that of a non-BPS D-brane in ten dimensions. As the D-brane approaches the…
In non-interacting or weakly-interacting 2D electron systems, the energy of the extended states increases as the perpendicular magnetic field approaches zero: the extended states "float up" in energy, giving rise to an insulator. However,…
It is shown that the momentum density of free electromagnetic field splits into two parts. One has no contribution to the net momentum due to the transversality condition. The other yields all the momentum. The angular momentum that is…
The genuine physical reasons explaining the delocalization effect of the Hubbard repulsion U are analyzed. First it is shown that always when this effect is observed, U acts on the background of a macroscopic degeneracy present in a…
Low-temperature scanning tunneling spectroscopy over Co nanoislands on Cu(111) showed that the surface states of the islands vary with their size. Occupied states exhibit a sizeable downward energy shift as the island size decreases. The…
This paper is addressed to the analysis of the set of observables of the bound-state beta-decay, which can be used for the experimental investigation of contributions of i) interactions beyond the Standard Model (SM) and of ii) the…
The transmitted wave that results from a collision of a wave packet which is initially to the left of a potential barrier depends in general on the amplitudes of negative momenta of the initial state. The exact form of this dependence is…
An external magnetic field, $H$, applied parallel to a quasi two-dimensional system modifies quantitatively and qualitatively the density of states. Using a self-consistent numerical approach, we study how this affects the entropy, $S$, the…
This paper explores two instances where dissipation plays a crucial role in curbing the unbounded energy growth of particles in time-dependent billiards. The first example involves an elliptical-like billiard with inelastic collisions…
We study in this article the asymptotic behavior of the Mindlin-Timoshenko system subject to a nonlinear dissipation acting only on the equations of the rotation angles. First, we briefly recall the existence of the solution of this system.…
The four-nucleon bound state and scattering below three-body breakup threshold are described based on the realistic coupled-channel potential CD Bonn + $\Delta$ which allows the excitation of a single nucleon to a $\Delta$ isobar. The…
It is shown that the momentum density of free electromagnetic field splits into two parts. One has no contribution to the net momentum due to the transversality condition. The other yields all the momentum. The angular momentum that…
We investigate the effect of a non-uniform deformation applied to one-dimensional (1D) quantum systems, where the local energy scale is proportional to $g_j = [\sin (j \pi / N)]^m$ determined by a positive integer $m$, site index $1 \leq j…
We study the possible existence of bound states of three $\Omega_{bbb}$ baryons. We consider only $S$ wave interactions and we start from recent lattice QCD results which give a strongly attractive potential between two $\Omega_{bbb}$…
In this work we systematically study both the mass spectra and strong decays of the nucleon and $\Delta$ resonances up to the $N=2$ shell within a unified quark model framework with chiral dynamics. In this framework we achieve a good…
The lower excitation spectrum of the nucleon and $\Delta$ is calculated in a relativistic chiral quark model. Contributions of the second order self-energy and exchange diagrams due-to pion fields to the mass spectrum of the SU(2) baryons…
This study appertains to the extraction of estimates for the masses and for the partial decay widths to pion-nucleon final states of the well-established (four-star) $s$ and $p$ baryon resonances below $2$ GeV. These estimates are…
Above a certain solid fraction, dense granular suspensions in water exhibit non-Newtonian behavior, including impact-activated solidification. Although it has been suggested that solidification depends on boundary interactions, quantitative…