相关论文: Intrinsic quadrupole moment of the nucleon
Recent ineleastic electron-proton scattering experiments have led to rather accurate values for the N->Delta transition quadrupole moment Q(N->Delta).The experimental results imply a prolate (cigar-shaped) intrinsic deformation of the…
To obtain further information on the geometric shape of the nucleon, the proton charge form factor is decomposed into two terms, which are connected respectively with a spherically symmetric and an intrinsic quadrupole part of the proton's…
The electromagnetic form factors are the most fundamental quantities to describe the internal structure of the nucleon and the shape of a spatially extended particle is determined by its {\it intrinsic} quadrupole moment which is first…
Information on the intrinsic deformation of the proton can be obtained by studying the electromagnetic p-->Delta+ quadrupole transition. Recent experiments have shown that the electric quadrupole (E2) strength in gamma p --> Delta+ is about…
A quark model relation between the neutron charge form factor and the N->Delta charge quadrupole form factor is used to predict the C2/M1 ratio in the N->Delta transition from the elastic neutron form factor data. Excellent agreement with…
Changes in the nucleon shape are investigated by letting the nucleon deform under the strong interactions with another nucleon. The parameters of the axial deformations are obtained by minimizing the static energy of the two nucleon system…
Using a covariant spectator constituent quark model we predict an electric quadrupole moment -0.043 efm^2 and a magnetic octupole moment -0.0035 efm^3 for the Delta+ excited state of the nucleon.
The electromagnetic excitation of the nucleon resonances is studied in the framework of Constituent Quark Models. Particular attention is devoted to the transition to the $\Delta$ resonance and to the issue of a possible deformation of…
Collective effects in deformed atomic nuclei present possible avenues of study on the non-spherical distribution of neutrons and the violation of the local Lorentz invariance. We introduce the weak quadrupole moment of nuclei, related to…
The nuclear quadruple moment is a fundamental character associated to the nuclei, this moment is related to the not purely spherical distribution in the nuclei, indeed its measure allows us to survey the geometric deformation of the nuclei…
Electric quadrupole (E2) matrix elements provide a measure of nuclear deformation and related collective structure. Ground-state quadrupole moments in particular are known to high precision in many p-shell nuclei. While the experimental…
Within the nuclear DFT approach, we determined the magnetic dipole and electric quadrupole moments for paired nuclear states corresponding to the proton (neutron) quasiparticles blocked in the p11/2- (n13/2+) intruder configurations. We…
We present here a new determination of the quadrupole moment Q of hyperfine-probe-nuclei states of three different In isotopes: the 5+ 192 keV excited state of 114In (probe for Nuclear Orientation experiments), the 9/2+ ground state of…
We compute the electric dipole moment of proton and neutron from lattice QCD simulations with N_f=2 flavors of dynamical quarks at imaginary vacuum angle theta. The calculation proceeds via the CP odd form factor F_3. A novel feature of our…
The \gamma* N -> \Delta(1232) transition is a window on hadron shape deformation, the applicability of perturbative QCD at moderate momentum transfers, and the influence of nonperturbative phenomena on hadronic observables. We explain that…
Supersymmetric model contributions to the neutron electric dipole moment arise via quark electric dipole moment operators, whose matrix elements are usually calculated using the Naive Quark Model (NQM). However, experiments indicate that…
The deformation of a nucleon embedded in various finite nuclei is considered by taking into account the distortion of the chiral profile functions under the action of an external field representing the nuclear density. The baryon charge…
We study the convergence of bound-state quadrupole moments in finite harmonic oscillator spaces. We derive an expression for the infrared extrapolation for the quadrupole moment of a nucleus and benchmark our results using different model…
We define the "quadrupole ratio" r_{Q}=\dfrac{Q_{0}(S)}{Q_{0}(B)} where Q_{0}(S) is the intrinsic quadrupole moment obtained from the static quadrupole moment of the 2_{1}^{+} state of an even-even nucleus and Q_{0}(B) the intrinsic…
In a previous paper \cite{Hatta:2020ltd}, we have pointed out the connection between the $CP$-odd three-gluon (Weinberg) operator and certain twist-four corrections in polarized deep inelastic scattering. Based on this observation, we give…