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We calculate the cross section of a pion diffraction dissociation in two jets with large transverse momenta originating from a hard gluon exchange between the pion constituents. To the leading logarithmic accuracy (in energy), the…

High Energy Physics - Phenomenology · Physics 2009-11-07 V. M. Braun , D. Yu. Ivanov , A. Schaefer , L. Szymanowski

The method of QCD sum rules has proven to be particularly useful in heavy quark physics, where a small distance scale is provided by the inverse heavy quark mass. We present two new examples for the application of this method to B-physics:…

High Energy Physics - Phenomenology · Physics 2009-09-25 A. Khodjamirian , R. Rückl

I calculate the form factors describing semileptonic and penguin-induced decays of B mesons into light pseudoscalar mesons. The form factors are calculated from QCD sum rules on the light-cone including contributions up to twist 4,…

High Energy Physics - Phenomenology · Physics 2009-10-31 Patricia Ball

The introduction of partially twisted boundary conditions allows weak and electromagnetic form factors to be evaluated at specified values of the hadronic momenta (and hence momentum transfers) in lattice simulations. We present and…

High Energy Physics - Lattice · Physics 2009-11-13 P. A. Boyle , J. M. Flynn , A. Juttner , C. T. Sachrajda , J. M. Zanotti

We report on the lowest moment of parton distribution functions and generalized form factors for the pion at several values of the momentum transfer. Calculations are performed for N_f=2 flavors of O(a) improved Wilson fermions with pion…

High Energy Physics - Lattice · Physics 2013-12-02 G. Bali , S. Collins , B. Glässle , M. Göckeler , N. Javadi-Motaghi , J. Najjar , W. Söldner , A. Sternbeck

We study the electromagnetic and meson-photon transition form factors (TFF) of light pseudoscalar mesons from the perturbative QCD (pQCD) approach. To comprehensively account for both the longitudinal and transverse nonperturbative dynamics…

High Energy Physics - Phenomenology · Physics 2025-06-06 Jian Chai , Shan Cheng

We present the application of the method of light-cone sum rules to the determination of baryonic form factors at intermediate momentum transfer. After reviewing the current status of this field we give some outlook on possible future…

High Energy Physics - Phenomenology · Physics 2008-11-26 Alexander Lenz

We compare two approaches to the description of pion Compton scattering at moderate momentum transfer, one being based on local duality QCD sum rules for the invariant amplitudes of the process, which have been derived recently, and the…

High Energy Physics - Phenomenology · Physics 2010-11-01 Claudio Coriano' , Hsiang-nan Li

We calculate the QCD moments of the pion structure function using Drell-Yan data on the quark distributions in the pion and a phenomenological model for the resonance region. The extracted higher twist corrections are found to be larger…

High Energy Physics - Phenomenology · Physics 2014-11-17 W. Melnitchouk

In this work, we employ a dispersion relation that allows to recover the electromagnetic form factor of the pion from its modulus along the unitarity cut. Unlike the standard dispersive approach, this method extends in a straightforward…

High Energy Physics - Phenomenology · Physics 2024-10-24 Pablo Sanchez-Puertas , Enrique Ruiz Arriola

We propose to introduce the intrinsic transversal momentum distribution functions (iTMDs), in conjunction with the light-cone distribution amplitudes (LCDAs), to elucidate the probability amplitude of encountering a meson state wherein the…

High Energy Physics - Phenomenology · Physics 2025-03-25 Jian Chai , Shan Cheng

New sum rules for $B\to \pi,K $ and $B\to \rho,K^*$ form factors are derived from the correlation functions expanded near the light-cone in terms of B-meson distribution amplitudes. The contributions of quark-antiquark and…

High Energy Physics - Phenomenology · Physics 2008-11-26 Alexander Khodjamirian , Thomas Mannel , Nils Offen

The accurate calculation of weak heavy-to-light form factors is crucial for the determination of CKM matrix elements from experimental data on B decays. In SCET, the soft-collinear effective theory, these form factors can, in the heavy…

High Energy Physics - Phenomenology · Physics 2007-05-23 Patricia Ball

In the framework of Dyson-Schwinger equations (DSE), we compute the $\gamma^*\gamma\to\pi^0$ transition form factor, $G(Q^2)$. For the first time, in a continuum approach to quantun chromodynamics (QCD), it was possible to compute $G(Q^2)$…

Nuclear Theory · Physics 2016-11-23 Khépani Raya

We consider the lightcone sum-rule (LCSR) description of the pion-photon transition form factor in combination with the renormalization group of QCD. The emerging scheme represents a certain version of Fractional Analytic Perturbation…

High Energy Physics - Phenomenology · Physics 2019-11-21 C. Ayala , S. V. Mikhailov , A. V. Pimikov , N. G. Stefanis

We discuss the evaluation of the transition form factor (TFF) $F^{\gamma*\gamma\pi^0}(Q^2)$ by means of QCD theory and by state-space reconstruction from topological data analysis. We first calculate this quantity in terms of quark-gluon…

High Energy Physics - Phenomenology · Physics 2019-06-21 N. G. Stefanis

It is shown that the data on the pion charge form factor admit the possibility for a substantial sea-quark components in the pion wave function. If the charge form factor is calculated with instant form kinematics in a constituent quark…

High Energy Physics - Phenomenology · Physics 2008-11-26 Q. B. Li , D. O. Riska

We consider the cross section of the deep inelastic pion electroproduction on a proton target at threshold for Q^2 in the region 5-10 GeV^2. The corresponding amplitudes are described in terms of two form factors which we calculate using…

High Energy Physics - Phenomenology · Physics 2008-11-26 V. M. Braun , D. Yu. Ivanov , A. Lenz , A. Peters

We present a lattice calculation of the electromagnetic form factor of the pion obtained using the tree-level Symanzik improved gauge action with two flavors of dynamical twisted Wilson quarks. The simulated pion masses range approximately…

High Energy Physics - Lattice · Physics 2009-11-06 R. Frezzotti , V. Lubicz , S. Simula

A state-of-the-art analysis of the pion-photon transition form factor is presented based on an improved theoretical calculation that includes the effect of a finite virtuality of the quasi-real photon in the method of light-cone sum rules.…

High Energy Physics - Phenomenology · Physics 2013-05-31 N. G. Stefanis , A. P. Bakulev , S. V. Mikhailov , A. V. Pimikov