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QCD sum rules are used to compute the first few moments of the mesonic quark momentum. Transverse, longitudinal and mixed transverse-longitudinal components are examined. The transverse size of the pion is shown to be dictated by the gluon…

High Energy Physics - Phenomenology · Physics 2009-10-22 Su H. Lee , T. Hatsuda , G. A. Miller

The radiative $\Delta \to \gamma N$ transition is examined at the real photon point $Q^2=0$ using the framework of light-cone QCD sum rules. In particular, we determine the sum rules for the transition form factors $G_M(0)$ and $R_{EM}$ up…

High Energy Physics - Phenomenology · Physics 2017-08-23 J. Rohrwild

The pion form factor calculation in the ``point-form'' of relativistic quantum mechanics is re-considered. Particular attention is given to the relation between the momentum of the system and the momentum transfer as well as to the quark…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. Desplanques , A. Amghar , L. Theussl

A lattice determination of the form factor and decay constants for the semileptonic decay of heavy pseudoscalar (PS) mesons at zero recoil is presented from which the soft pion relation is satisfied. Chiral extrapolation of the form factor…

High Energy Physics - Lattice · Physics 2015-06-25 UKQCD Collaboration , K. C. Bowler , C. M. Maynard , L. Lellouch , J. Nieves , D. G. Richards , L. Del Debbio , J. M. Flynn , V. I. Lesk

The neutral pion generates the leading pole contribution to the hadronic light-by-light tensor, which is given in terms of the nonperturbative transition form factor $\mathcal{F}_{\pi^0\gamma\gamma}(q_1^2,q_2^2)$. Here we present an…

The pion electromagnetic form factor with leading and next-to-leading twist corrections are studied in the framework of pQCD approach. We find that, at small momentum transfer regions, Sudakov effects cannot provide a strong enough…

High Energy Physics - Phenomenology · Physics 2007-05-23 Zheng-Tao Wei , Mao-Zhi Yang

In a study of the elastic pion form factor for large momentum transfers based on a modified perturbative QCD (PQCD) approach we have included helicity components that are customarily neglected. Along with the inclusion of transverse…

High Energy Physics - Phenomenology · Physics 2009-10-28 Siwen Wang , Leonard S. Kisslinger

The purely nonperturbative soft contribution to the $\gamma^* p \to \Delta^+$ transition form factors is estimated using the local quark-hadron duality approach. Our results show that the soft contribution is dominated by the magnetic…

High Energy Physics - Phenomenology · Physics 2014-11-17 V. M. Belyaev , A. V. Radyushkin

In this article, we calculate the contribution from the nonfactorizable soft hadronic matrix element to the decay $B^0\to \chi_{c1} \pi^0$ with the light-cone QCD sum rules. The numerical results show that its contribution is rather large…

High Energy Physics - Phenomenology · Physics 2015-05-13 Zhi-Gang Wang

We describe the calculation of the $B\rightarrow \pi$ hadronic matrix element from operator product expansion near the light-cone in QCD. In the resulting sum rules, the form factors $f^+$ and $F_0$ determining this matrix element are…

High Energy Physics - Phenomenology · Physics 2016-09-06 A. Khodjamirian , R. Rückl

We calculate the $D^*D\pi$ and $B^*B\pi$ couplings using QCD sum rules on the light-cone. In this approach, the large-distance dynamics is incorporated in a set of pion wave functions. We take into account two-particle and three-particle…

High Energy Physics - Phenomenology · Physics 2014-11-17 V. M. Belyaev , V. M. Braun , A. Khodjamirian , R. Rückl

We present an improved calculation of all B -> light pseudoscalar formfactors from light-cone sum rules, including one-loop radiative corrections to twist-2 and twist-3 contributions, and leading order twist-4 corrections. The total…

High Energy Physics - Phenomenology · Physics 2017-08-23 Patricia Ball , Roman Zwicky

We scrutinize recent findings on the charged-pion elastic form factor and the form factors entering in neutral-meson-to-photons transition amplitudes within the framework of QCD sum rules.

High Energy Physics - Phenomenology · Physics 2015-06-05 Irina Balakireva , Wolfgang Lucha , Dmitri Melikhov

We study the effects of instantons on the charged pion electro-magnetic formfactor at intermediate momenta. In the Single Instanton Approximation (SIA), we predict the pion formfactor in the kinematic region Q^2=2-15 GeV^2. By developing…

High Energy Physics - Phenomenology · Physics 2009-11-07 P. Faccioli , A. Schwenk , E. V. Shuryak

We present an improved calculation of $B\to$ light vector form factors from light-cone sum rules, including one-loop radiative corrections to twist-2 and twist-3 contributions, and leading order twist-4 corrections. The total theoretical…

High Energy Physics - Phenomenology · Physics 2008-11-26 Patricia Ball , Roman Zwicky

The charged pion form factor, Fpi(Q^2), is an important quantity which can be used to advance our knowledge of hadronic structure. However, the extraction of Fpi from data requires a model of the 1H(e,e'pi+)n reaction, and thus is…

The gravitational form factors (GFFs) of pions are calculated from a top-down holographic quantum chromodynamics (QCD) approach with momentum transfer dependence for the first time. It is important because the GFFs of hadrons have…

High Energy Physics - Phenomenology · Physics 2024-11-13 Daisuke Fujii , Akihiro Iwanaka , Mitsuru Tanaka

We study the pion form factor F^{\pi \gamma\gamma^*}(Q^2) in the light-cone sum rule approach, accounting for radiative corrections and higher twist effects. Comparing the results to the CLEO experimental data on F^{\pi…

High Energy Physics - Phenomenology · Physics 2016-09-06 Alexander Schmedding , Oleg Yakovlev

We provide a theoretical update of the calculations of the pi0-gamma*-gamma form factor in the LCSR framework, including up to six polynomials in the conformal expansion of the pion distribution amplitude and taking into account twist-six…

High Energy Physics - Phenomenology · Physics 2011-03-22 S. S. Agaev , V. M. Braun , N. Offen , F. A. Porkert

A new method is suggested to calculate the $B\to \pi\pi$ hadronic matrix elements from QCD light-cone sum rules. To leading order in $\alpha_s$ and $1/m_b$, the sum rule reproduces a factorizable matrix element, in accordance with the…

High Energy Physics - Phenomenology · Physics 2009-10-31 Alexander Khodjamirian
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