Related papers: On the electron to proton mass ratio and the proto…
So far the only seemingly significant indication of a cosmological variation exists for the proton-to-electron mass ratio as stated by Reinhold et al. (2006). The measured indication of variation is based on the combined analysis of H2…
We determine theoretically the relation between the total number of protons $N_{p}$ and the mass number $A$ (the charge to mass ratio) of nuclei and neutron cores with the model recently proposed by Ruffini et al. (2007) and we compare it…
We derive the electric and magnetic form factors of the neutron in the framework of a relativistic constituent quark model. Our parameter free prediction agrees well with a recent, accurate measurement. The relativistic features of the…
The electromagnetic form factors are crucial to our understanding of the proton internal structure, and thus provide a strong constraint of the distributions of the charge and magnetization current within the proton. We adopted the…
We present an algebraic approach to the internal structure of baryons in terms of three constituents. We investigate a collective model in which the nucleon is regarded as a rotating and vibrating oblate top with a prescribed distribution…
A simple statistical model in terms of light-front kinematic variables is used to explain the nuclear EMC effect in the range $x \in [0.2,~0.7]$, which was constructed by us previously to calculate the parton distribution functions (PDFs)…
We study the nuclear ($A$) dependence of the European Muon Collaboration (EMC) effect at high values of $x$ ($x \geq 0.6$). Our approach makes use of conventional nuclear degrees of freedom within the Relativistic Impulse Approximation. By…
An almost model-independent parametrization for the ratio of the total cross section to the elastic slope, as function of the center of mass energy, is introduced. The analytical result is based on the approximate relation of this quantity…
The new parameterization of the generalized parton distributions t-dependence is proposed. It allows one to reproduce sufficiently well the electromagnetic form factors of the proton and neutron at small and large momentum transfer. The…
A reanalysis of unpolarized electron-proton elastic scattering data is done in terms of the electric to magnetic form factor squared ratio. This observable is in principle more robust against experimental correlations and global…
Results are presented for hadron spectroscopy with gauge groups SU(N) with N=3, 5, 7. Calculations use the quenched approximation. Lattice spacings are matched using the static potential. Meson spectra show independence on N and…
We have long ago derived a theoretical relation between the mass of the electron and the fine structure constant \cite{Nottale1994}, which writes to lowest order $\alpha \ln (m_{\mathbb{P}}/m_e) = 3/8$ (where $m_{\mathbb{P}}$ is the Planck…
The possible cosmological variation of the proton-to-electron mass ratio was estimated by measuring the H_2 wavelengths in the high-resolution spectrum of the quasar Q~0347-382. Our analysis yielded an estimate for the possible deviation of…
A method for computing electromagnetic properties of hadrons in lattice QCD is applied to the extraction of electromagnetic properties of the octet baryons. This allows a determination of the full dependence of the baryon masses on the…
We present results for the electromagnetic form factors of the proton and neutron computed on the $(2 + 1)$-flavor Coordinated Lattice Simulations (CLS) ensembles including both quark-connected and -disconnected contributions. The $Q^2$-,…
We present a lattice calculation of the mass difference between neutron and proton, for which we find $ M_n - M_p = 1.73(69) \, \text{MeV}$. This is obtained at 1st order in the $QED$ coupling $\alpha_{EM}$ and in the mass difference…
We compute the electromagnetic form factors of the proton and neutron using lattice QCD with $N_f = 2 + 1 + 1$ twisted mass clover-improved fermions and quark masses tuned to their physical values. Three ensembles with lattice spacings of…
Understanding the differences between the distribution of quarks bound in protons and neutrons is key for constraining the mechanisms of SU(6) spin-flavor symmetry breaking in Quantum Chromodynamics (QCD). While vast amounts of proton…
On the basis of the representation of the generalized structure of nucleons a new model of the hadron interaction at high energies is presented. The new t-dependence of the generalized parton distributions (GPDs) is obtained from the…
The shape of the electron is studied using lowest-order perturbation theory. Quantities used to probe the structure of the proton: form factors, generalized parton distributions, transverse densities, Wigner distributions and the angular…