Physics of Particles and Nuclei Letters 
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This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.Renormalon-Chain Contributions to Two-Point Correlators of Nonlocal Quark Currents
AbstractWe calculate, within massless QCD, two-point correlator of nonlocal (composite) vector quark currents with arbitrary-length chains of the simplest fermion loops being inserted into gluon lines. Within the large\({{n}_{f}}\) (or large\({{\beta }_{0}}\)) approximation, the correlator defines a perturbative contribution to the leading-twist distribution amplitudes for light mesons. Our results are consistent with a number of special cases in the literature. We consider functionals of the correlator, which are important for the phenomenology, and their properties as functional series. (Source: Physics of Particles and Nuclei Letters)
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
Pair Quarkonium Production in Higgs Boson Decay
AbstractThe production of a pair of\(J{\text{/}}\Psi \) and\(\Upsilon \) mesons in Higgs boson (H) decay is studied on the basis of the perturbative Standard Model and a relativistic quark model. We calculate relativistic corrections in the decay amplitudes and decay widths connected with the relative motion of heavy quarks. (Source: Physics of Particles and Nuclei Letters)
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
Confinement Potential in Soft Wall Holographic Approach to QCD
We present the results for the confinement potential of the Cornell type within the framework of the generalized Soft Wall holographic model (with quadratic dilaton background in the metric) which contains an additional parameter responsible for the value of intercept of the linear Regge spectrum. Next, we note that the Cornell potential arises also in some Soft Wall models which do not lead to Regge like spectrum. As an example, we demonstrate this property in a model with linear dilaton background in the metric. This example is at odds with intuition based on the hadron string picture that the linearly rising potential a...
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
Solution of the Kinetic Equation Taking into Account Resonance in the Compton Process in a Magnetized Medium
AbstractThe solution of the kinetic equation for finding the distribution function of photons of two possible polarizations in an equilibrium nonrelativistic\({{e}^{ + }}{{e}^{ - }}\) plasma in a relatively strong magnetic field is considered taking into account resonance on a virtual electron. Using the Laplace transform and the expansion of the distribution function in Legendre polynomials, the problem is reduced to a system of differential equations for the coefficients of this expansion. The solution is presented as an integral in the complex plane. (Source: Physics of Particles and Nuclei Letters)
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
Spiral Structure of Galaxies in Generalised Gravitational Theories
AbstractMotion of stars in galactic discs is considered in the epicyclic approximation given potentials derived from gauge gravitation theory and quadratic gravity. It is assumed that an instability of circular orbits of stars to small perturbations in such potentials may result in formation of spiral arms. Our aim is to determine the range of magnitudes of unknown coefficients in the Lagrangians of these theories which would allow this instability to occur. (Source: Physics of Particles and Nuclei Letters)
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
Double Longitudinal-Spin Asymmetries in Direct Photon Production at NICA
AbstractIn this paper we calculate double longitudinal-spin asymmetries in the direct photon production at the NICA collider in the leading order of the collinear parton model. Predictions for potential measurements of asymmetries are presented at different energies of the NICA collider. (Source: Physics of Particles and Nuclei Letters)
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
A Note on Stress-Energy Tensor and Variational Principle for Null Strings
AbstractA straightforward application of the variational principle to null strings meets difficulties since string ’s world-sheets are degenerate. It is known that the variational principle in this case can be formulated with the help of two-vector density on the string world-sheet which plays a role of Lagrange multipliers. It is shown that recently suggested stress-energy tensor of null strings can be derive d by variation over the background metric of the action used to describe tensionless limit in the string theory. One of the Lagrange multipliers is related to the energy of the null string. (Source: Physics of Part...
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
Exact Four-Point Amplitudes in Various Fishnet Theories
AbstractIn this work we have studied the behaviour of amplitudes in biscalar and\(\mathfrak{N} = 1\) supersymmetric fishnet theories in different kinematic limits and in various regimes of the coupling constant. The analysis is provided for both 4d and 6d cases. (Source: Physics of Particles and Nuclei Letters)
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
Four-Quark Nature of Light Scalar Mesons
AbstractIt is shown that all predictions for the light scalars, based on their four-quark nature, are supported by experiment. The future research program is outlined also. (Source: Physics of Particles and Nuclei Letters)
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
The Evolution of the Majorana Neutrino Mass Renormalization Group in the Super-Weak Theory
AbstractThe super-weak interaction includes three simple extensions of the standard model: gauge extension, fermionic extension, and scalar extension. All of these extensions are strongly influenced by their complex phenomenology. They can explain a number of unresolved questions in particle physics and cosmology, including the genesis of dark matter, cosmic inflation, asymmetry of matter and antimatter, neutrino masses, and vacuum stability, if combined into a single structure. This is an extension of the gauge group of the standard model\({{G}_{{{\text{SM}}}}}\) by\({{G}_{{{\text{SM}}}}} \otimes U{{(1)}_{Z}}\) without an...
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
Quantum and Classical Local P-Violation
AbstractClassical analogs of chiral vortical and magnetic effects, generated by the currents possessing the hydrodynamical helicity are considered. The earlier found phenomenon of helicity separation in heavy-ion collisions leads to the appearance of currents of opposite signs at the different sides of reaction plane, accompanied by the current parallel to the plane. We discuss briefly relation between classical and quantum chiral effects. (Source: Physics of Particles and Nuclei Letters)
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
Energy Levels of Three-Particle Muon –Electronic Ions
AbstractThe muonic 2P –2S Lamb shift in muon–electron atoms and ions of helium, lithium, beryllium, and boron with the electron in the ground state is calculated by perturbation theory in the fine structure constant and the electron–muon mass ratio. The corrections of first and second orders of perturbation theory on the vacuum polarization, nuclear structure, and recoil are taken into account. (Source: Physics of Particles and Nuclei Letters)
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
Rare Decays of Neutral B Mesons into Four Charged Leptons in the Standard Model
AbstractAs part of the Standard Model (SM), we present new theoretical predictions for the branching ratio and differential distributions for the\({{\bar {B}}_{d}} \to {{\mu }^{ + }}{{\mu }^{ - }}{{e}^{ + }}{{e}^{ - }}\) decay. We take into consideration the contributions\({{\rho }^{0}}(770)\) and\(\omega (782)\) of resonances; the main contributions of four charmonium resonances:\(\psi (3770)\),\(\psi (4040)\),\(\psi (4160)\), and\(\psi (4415)\); the contributions of the tails from\({J \mathord{\left/ {\vphantom {J \psi }} \right. \kern-0em} \psi }\) and\(\psi (2S)\) resonances; and the nonresonant contribution of the\(b{...
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
Double Compton Process in a Strongly Magnetized Plasma
AbstractThe process of double Compton scattering,\(e\gamma \to e\gamma \gamma \), in a strongly magnetized charge-asymmetric cold electron plasma is considered. The amplitude of the process is obtained, and selection rules for photon polarizations are found. The double Compton scattering in such a plasma is shown to be an efficient process for the production of polarized photons. (Source: Physics of Particles and Nuclei Letters)
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
Polarization of Gravitational Waves in Hybrid Metric-Palatini $$f(R)$$ -Gravity
AbstractThe work is devoted to the calculation of the number of polarization states in hybrid metric-Palatini\(f(R)\)-gravity. In addition, the problem of the discrepancy between the number of polarization modes and the number of degrees of freedom in massive scalar-tensor theories is considered on the example of hybrid\(f(R)\)-gravity. (Source: Physics of Particles and Nuclei Letters)
Source: Physics of Particles and Nuclei Letters - June 1, 2023 Category: Physics Source Type: research
