相关论文: Non-spherical proton shape and hydrogen hyperfine …
To date the magnetic radius of the proton has been determined only by means of electron-proton scattering, which is not free of controversies. Any existing atomic determinations are irrelevant because they are strongly model-dependent. We…
Improved measurements of the proton's structure are now possible thanks to significant technical advances that allow us to probe the proton with polarized photons. These measurements have shown that the proton is not as simple as previously…
The angular distribution of the emitted electrons, following the two--photon ionization of the hydrogen--like ions, is studied within the framework of second order perturbation theory \textit{and} the Dirac equation. Using a density matrix…
We present the leading-order prediction of baryon chiral perturbation theory for the proton polarizability contribution to the 2S hyperfine splitting in muonic hydrogen, and compare with the results of dispersive calculations.
The contribution of \Delta isobar to the correction on proton polarizability in the hyperfine splitting of hydrogen and muonic hydrogen is calculated with the account of the experimental data on N-\Delta transition form factors.
Modern electron scattering experiments have determined the proton electric form factor, G_{Ep}(Q^2), to high precision. We utilize this data, represented by the different form factor parametrizations, to compute the third Zemach moment of…
The projection onto the Light-Front of a Minkowski space Faddeev-Bethe-Salpeter equation model truncated at the valence level is applied to study the proton structure with constituent quarks. The dynamics of the model has built-in: (i) a…
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…
There is experimental and theoretical evidence that the broad rapidity distribution of net proton yield in central heavy-ion collisions at SPS energies could be a signal of non-equilibrium properties of the system. We show that the broad…
In this paper the distribution of charged particles is constructed under the approximation of ambipolar diffusion. The results of mathematical modelling in two-dimensional case taking into account the velocities of the system are presented.
In this paper, we apply the Maximum Entropy Method to estimate the proton radius and determine the valence quark distributions in the proton at extremely low resolution scale Q$^{2}_{0}$. Using the simplest functional form of the valence…
We present results for the $x$ dependence of the unpolarized, helicity, and transversity isovector quark distributions in the proton using lattice QCD, employing the method of quasi-distributions proposed by Ji in 2013. Compared to a…
The light-cone Photon wave function in explicit helicity states, valid for massive quarks and in both momentum and configuration space, is presented by considering the leading order photon-proton hard scattering, i.e., the splitting quark…
The usefulness of study of hyperfine splitting in the hydrogen atom is limited on a level of 10 ppm by our knowledge of the proton structure. One way to go beyond 10 ppm is to study a specific difference of the hyperfine structure intervals…
High degree of electron spin polarization is of crucial importance in operation of spintronic devices. We study the propagation of spin-polarized electrons through a boundary between two n-type semiconductor regions with different doping…
The largest uncertainty in calculations of hydrogen ground-state hyperfine splitting comes from corrections due to proton stucture. We review these corrections, with special mention of the inelastic, or polarizability, corrections which…
A model proton wave function, constructed using Poincare invariance, and constrained by recent electromagnetic form factor data, is used to study the shape of the proton. Spin-dependent quark densities are defined as matrix elements of…
Highly correlated states of electrons are thought to produce quasiparticles with very unusual properties. Here we consider how these properties are manifested in space-time propagation. Specifically, we discuss how spin-charge separation is…
We discuss production of nonphotonic electrons in proton-proton scattering at RHIC. The distributions in rapidity and transverse momentum of charm and bottom quarks/antiquarks are calculated in the $k_t$-factorization approach. We use…
Baym and Farrar (arXiv:2601.02300v1) have recently pointed out a puzzle in understanding the role of the hyperfine interaction in the ground state of a hydrogen atom. If one uses a variational wave function in which the Bohr radius, $a_0$…