Related papers: Proton polarizability contribution to the hydrogen…
Effects of the spin-dependent gluon distributions on J/$\psi$ productions in polarized ep and pp collisions are investigated. These productions serve as a very clean probe of the spin-dependent gluon distributions in a proton.
High-precision measurements of the proton radius from laser spectroscopy of muonic hydrogen demonstrated up to six standard deviations smaller values than obtained from electron-proton scattering and hydrogen spectroscopy. The status of…
We report the measurements of the transverse ($P'x$) and longitudinal ($P'z$) components of the polarization transfer to a bound proton in carbon via the quasi-free $^{12}{\rm C}(\vec e,e'\vec p)$ reaction, over a wide range of missing…
We find a new correction to the hydrogen atom ground state hyperfine energy levels splitting in magnetic field. It can be interpreted as magnetic focusing of the wave function at the origin. The effect might be within the reach of…
A rigorous formalism for determining the electric dipole polarizability of a three-hadron bound complex in the case that the system has only one bound (ground) state has been elaborated. On its basis, by applying a model wave function that…
Polarization observables for the reaction $\bar p+p\to e^++e^-$ are given in terms of three independent complex amplitudes, in presence of two photon exchange. General expressions for the differential cross section and the polarization…
Proton-proton fusion is considered in the effective field theory of Kaplan, Savage and Wise. Coulomb effects are included systematically in a non-perturbative way. Including the dimension-eight derivative coupling which determines the…
By solving the two-body Schordinger equation in a very high precise nonperturbative numerical (NPnum) way, we reexamine the contributions of fine, hyperfine structure splittings of muonic hydrogen based on the Breit potential. The…
We study the ionization process involving antiproton and hydrogen in the energy range between 0.1 keV to 500 keV, using single center close coupling approximation. We construct the scattering wave function using B-spline bases. The results…
The nuclear polarization of $\mathrm{H}_2$ molecules formed by recombination of nuclear polarized H atoms on the surface of a storage cell initially coated with a silicon-based polymer has been measured by using the longitudinal double-spin…
The pp polarization data confirm the presence of a diffractive-like (Pomeron) contribution in the spin-flip amplitude. The extrapolation to RHIC energies does not appear very promising.
The two-photon decay in hydrogen-like ions is investigated within the framework of second order perturbation theory and Dirac's relativistic equation. Special attention is paid to the angular correlation of the emitted photons as well as to…
We theoretically study the influence of laser polarization in inelastic scattering of electrons by hydrogen atoms in the presence of a circularly polarized laser field in the domain of field strengths below $10^{7}$ V/cm and high projectile…
The one-loop self-energy correction to the hyperfine structure splitting of the 1s and 2s states of hydrogenlike ions is calculated both for the point and finite nucleus. The results of the calculation are combined with other corrections to…
Polarized parton distributions and structure functions of the nucleon are analyzed in the improved valon model. The valon representation provides a model to represent hadrons in terms of quarks, providing a unified description of bound…
We estimate two-photon exchange contribution to the process $e^+ +e^- \to p + \bar{p}$. The two-photon exchange corrections to double spin polarization observables and form factors in the time-like region are calculated. The corrections are…
We predict the values for baryon forward spin polarizabilities in fully covariant ChPT and including the virtual contributions of the spin-3/2 states. As the nucleon results are in good agreement with the experimental data and they do not…
An algebraic Ansatz for the proton's Poincar\'e-covariant wave function, which includes both scalar and pseudovector diquark correlations, is used to calculate proton valence, sea, and glue distribution functions (DFs). Regarding…
We examine a method of studying the Z polarization in $H\to ZZ \to \ell^+ \ell^- \nu \bar{\nu}$ in proton-proton collisions at the Large Hadron Collider (LHC). Included are the dominant contributions: gluon fusion production of the Higgs…
The behavior of the gluon distribution function and the reduced cross section considered from the proton structure function and its derivatives at low values of $x$. These behaviors studied and compared with the experimental data. These…