Meson Production in Proton-Proton Collisions in the Naive Non-Abelianization Approximation and the Role of Infrared Renormalons

We calculate the "naive non-abelianization" (NNA) contributions of the higher-twist Feynman diagrams to the large-$p_T$ inclusive pion production cross section in proton-proton collisions in the case of the running coupling and frozen coupling approaches. We compare the resummed "naive non-abelianization" higher-twist cross sections with the ones obtained in the framework of the frozen coupling approach and leading-twist cross section. The structure of infrared renormalon singularities of the higher twist subprocess cross section and it's resummed expression are found. We discuss the phenomenological consequences of possible higher-twist contributions to the pion production in proton-proton collisions in within NNA.Comment: 17 pages, 9 figure

The Relativistic Linear Singular Oscillator

Exactly-solvable model of the linear singular oscillator in the relativistic configurational space is considered. We have found wavefunctions and energy spectrum for the model under study. It is shown that they have correct non-relativistic limits.Comment: 14 pages, 12 figures in eps format, IOP style LaTeX file (revised taking into account referees suggestions

Infrared renormalons and single meson production in proton-proton collisions

In this article, we investigate the contribution of the higher twist Feynman diagrams to the large-$p_T$ inclusive pion production cross section in proton-proton collisions and present the general formulae for the higher twist differential cross sections in the case of the running coupling and frozen coupling approaches. The structure of infrared renormalon singularities of the higher twist subprocess cross section and the resummed expression (the Borel sum) for it are found. We compared the resummed higher twist cross sections with the ones obtained in the framework of the frozen coupling approximation and leading twist cross section. We obtain, that ratio $R$ for all values of the transverse momentum $p_{T}$ of the pion identical equivalent to ratio $r$. It is shown that the resummed result depends on the choice of the meson wave functions used in calculation. Phenomenological effects of the obtained results are discussed.Comment: 28 pages, 13 figure

Factorization method for difference equations of hypergeometric type on nonuniform lattices

We study the factorization of the hypergeometric-type difference equation of Nikiforov and Uvarov on nonuniform lattices. An explicit form of the raising and lowering operators is derived and some relevant examples are given.Comment: 21 page

Approximate Solutions to the Klein-Fock-Gordon Equation for the Sum of Coulomb and Ring-Shaped-Like Potentials

We consider the quantum mechanical problem of the motion of a spinless charged relativistic particle with mass M, described by the Klein-Fock-Gordon equation with equal scalar Sr→ and vector Vr→ Coulomb plus ring-shaped potentials. It is shown that the system under consideration has both a discrete at EMc2 energy spectra. We find the analytical expressions for the corresponding complete wave functions. A dynamical symmetry group SU1,1 for the radial wave equation of motion is constructed. The algebra of generators of this group makes it possible to find energy spectra in a purely algebraic way. It is also shown that relativistic expressions for wave functions, energy spectra, and group generators in the limit c⟶∞ go over into the corresponding expressions for the nonrelativistic problem

Analytical solutions for the Klein–Gordon equation with combined exponential type and ring-shaped potentials

Abstract In this study, we have successfully obtained the analytical solutions for the Klein–Gordon equation with new proposed a non-central exponential potential $$V\left( r \right) = D\left[ {1 - \sigma_{0} \coth (\alpha r)} \right]^{2} + (\eta_{1} + \eta_{2} \cos \theta )/r^{2} \sin^{2} \theta$$ V r = D 1 - σ 0 coth ( α r ) 2 + ( η 1 + η 2 cos θ ) / r 2 sin 2 θ . Our approach involves a proper approximation of the centrifugal term, with $${l}{\prime}$$ l ′ representing the generalized orbital angular momentum quantum number, and the utilization of the Nikiforov–Uvarov method. The resulting radial and angular wave functions are expressed in terms of Jacobi polynomials, and the corresponding energy equation is also derived. Our calculations of the eigenvalues for arbitrary quantum numbers demonstrated significant sensitivity to potential parameters and quantum numbers. Additionally, we evaluate the dependence of energy eigenvalues on screening parameter $$\alpha$$ α for arbitrary quantum numbers $$n_{r}$$ n r and $$N$$ N to establish the accuracy of our findings. Furthermore, we determine the non-relativistic limits of the radial wave function and energy equation, which align with corresponding previous results in the case where $$\eta_{1} = \eta_{2} = 0$$ η 1 = η 2 = 0