The problem of the position and spin in relativistic quantum mechanics is analyzed detail. It definitively shown that operators Foldy-Wouthuysen representation (but not Dirac one) are quantum-mechanical counterparts classical variables. probabilistic interpretation valid only for wave functions. discussed. spin-orbit interaction does exist a free particle if conventional orbital angular momentum rest-frame used. Alternative definitions based on noncommutative geometry, do satisfy standard...

Molecular clusters are aggregates of molecules weakly bound by the van der Waals force between molecules. Removing one electron from each constitutive molecule results in bond cleavages through Coulomb explosion. This provides an ideal prototype to further study environmental effects played fragmented ion on other at molecular scale. Here, we report experimental measurement two-body explosion (CO)22+ and (CO)32+, produced a 40 keV Ar2+ double-electron capture collision with CO dimer trimer....

Abstract Fourth-generation synchrotron light sources pursue ultra-high brightness and high spatial coherence, aiming to reduce beam emittance the diffraction-limit, which imposes stricter requirements on stability of storage ring mechanical system. Mechanical support serves as foundation for all physical components, ensuring their corresponding performance. This study utilizes Design Experiments method simulate analyze effects different boundary conditions component structures eigenfrequency...

General relativistic quantum dynamics of twisted (vortex) Dirac particles is constructed. The Hamiltonian and equations motion in the Foldy-Wouthuysen representation are derived for a electron arbitrary electric magnetic fields. A critical experiment verification results proposed. new important effect radiative orbital polarization beam field resulting nonzero average projection intrinsic angular momentum on direction predicted.

A theoretical description of twisted (vortex) electrons interacting with electric and magnetic fields is presented, based on Lorentz transformations. The general dynamical equations motion a electron an intrinsic orbital angular momentum in external field are derived. Methods for the extraction vortex beam given polarization manipulation such developed.

Relativistic light-front bound-state equations for double-heavy mesons, baryons and tetraquarks are constructed in the framework of supersymmetric light front holographic QCD. Although heavy quark masses strongly break conformal symmetry, supersymmetry embedding semiclassical dynamics still holds. The theory, derived from five-dimensional anti--de Sitter space, predicts that form confining potential Hamiltonian is harmonic even quarks. Therefore, basic underlying mechanism, which transforms...

Abstract The use of a (quasi)uniform magnetic field opens new possibilities for the production twisted particles having orbital angular momenta. We ascertain these possibilities. Quantum states suitable creation charged in uniform are determined. particle penetration from solenoid to vacuum or another is analyzed detail. It shown that previously proposed approach can be utilized successful positrons and positroniums. also find effect increasing uncertainty phase rotation with distance passed...

The Abelian decomposition of QCD which decomposes the gluons to color neutral binding and colored valence shows that can be viewed as restricted (RCD) made has source, simplifies dynamics greatly. In particular, it tells gauge covariant treated constituents hadrons, generalizes quark model gluon model. So provides a comprehensive picture glueballs their mixing with quarkoniums, predicts new hybrid hadrons quarks gluons. We discuss how these predictions could confirmed experimentally....

The analysis of twisted (vortex) paraxial photons and electrons is fulfilled in the framework relativistic quantum mechanics. use Foldy-Wouthuysen representation radically simplifies description clarifies fundamental properties particles. It demonstrated that other structured are luminal. Their subluminality apparently takes place because photon energy also contributed by a hidden motion. This motion vanished averaging disappears semiclassical based on expectation values momentum velocity...

For a twisted (vortex) Dirac particle in nonuniform electric and magnetic fields, the relativistic Foldy-Wouthuysen Hamiltonian is derived including high order terms describing new effects. The result obtained shows for first time that spin-$1/2$ possesses tensor polarizability measurable (spectroscopic) quadrupole moment. We have calculated former parameter evaluated latter one electron. of electron can be measured storage ring because beam with an initial orbital polarization acquires...

A theory of twisted (and other structured) paraxial electrons in a uniform magnetic field is developed. The obtained general quantum-mechanical solution the relativistic equation contains commonly accepted result as specific case unstructured electron waves. Unlike all precedent investigations, present study describes structured states which are not plane waves along direction. In weak-field limit, our (unlike existing theory) consistent with well-known for free beams. observable effect...

The aim of these lectures is to convey a working knowledge Light Front Holographic QCD and Supersymmetric QCD. We first give an overview holographic in general then concentrate on the application methods quantized light front form. show how implementation supersymmetric algebra fixes interaction one can obtain hadron mass spectra with minimal number parameters. also treat propagators compare approach other non-perturbative methods. In last chapter we describe electromagnetic form factors.

Abstract A compact accelerator-driven neutron source is proposed at Sino-French Institute of Nuclear Engineering and Technology, Sun Yat-Sen University, called University Proton Accelerator Facility (SYSU-PAFA). The proton accelerator composed a electron cyclotron resonance source, four-vane radio frequency quadrupole (RFQ), an alternative phase focusing drift tube linac (APF-DTL). It can accelerate 10 mA beam to 8 MeV. Due the high current, matching particularly important. In order achieve...

We analyze the nucleon structure of $\ensuremath{\alpha}$-decaying nucleus to see if it can be visible in experimental bremsstrahlung spectra emitted photons which accompany such a decay. develop new formalism model taking into account distribution nucleons nuclear system. conclude following. (1) After inclusion calculated spectrum is changed very slowly for majority nuclei. However, we have observed that changes really exist $^{106}\mathrm{Te}$ (${Q}_{\ensuremath{\alpha}}=4.29$ MeV,...