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Related papers: QCD Constraints on Form Factor Shapes

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Large-distance effects, which lead to the spin-flip part of the hadron -pomeron coupling in QCD -models, are discussed. We study spin asymmetries in exclusive reactions and in diffractive $Q \bar Q$ and vector meson production which are…

High Energy Physics - Phenomenology · Physics 2007-05-23 S. V. Goloskokov

I give a brief outline of the theoretical framework for the modern treatment of the strong interaction effects in heavy quark decays, based on first principles of QCD. This model-independent approach is required to meet the precision of…

High Energy Physics - Phenomenology · Physics 2014-11-17 N. Uraltsev

We evaluate the impact of recent developments in hadron phenomenology on extracting possible fundamental tensor interactions beyond the standard model. We show that a novel class of observables, including the chiral-odd generalized parton…

High Energy Physics - Phenomenology · Physics 2015-10-21 Aurore Courtoy , Stefan Baessler , Martin Gonzalez-Alonso , Simonetta Liuti

The role of Poincar\'e covariant space-time translations is investigated in the case of a relativistic quantum mechanics approach to the pion charge form factor. It is shown that the related constraints are generally inconsistent with the…

Nuclear Theory · Physics 2015-05-18 Bertrand Desplanques , Yu Bing Dong

An effective description of hadronic matter in terms of "effective free particles" is presented. Repulsive interactions among the hadrons have been modelled by Excluded volume correction by considering the hadrons as liquid drops, whose…

High Energy Physics - Phenomenology · Physics 2025-04-23 Somenath Pal

Lattice simulations of QCD have produced precise estimates for the masses of the lowest-lying hadrons which show excellent agreement with experiment. By contrast, lattice results for the vector and axial vector form factors of the nucleon…

High Energy Physics - Lattice · Physics 2011-09-23 B. B. Brandt , S. Capitani , M. Della Morte , D. Djukanovic , J. Gegelia , G. von Hippel , A. Juttner , B. Knippschild , H. B. Meyer , H. Wittig

An introduction to the method of QCD sum rules is given for those who want to learn how to use this method. Furthermore, we discuss various applications of sum rules, from the determination of quark masses to the calculation of hadronic…

High Energy Physics - Phenomenology · Physics 2016-11-23 Pietro Colangelo , Alexander Khodjamirian

The strange quark plays a unique role in QCD, reflecting its intermediate mass between the light and heavy quarks. In recent years, remarkable progress has been made in the spectroscopy of baryons with strangeness. Many new features of the…

High Energy Physics - Phenomenology · Physics 2021-07-14 Tetsuo Hyodo , Masayuki Niiyama

There exists a large field for phenomenological models in which the knowledge of the structure of hadrons in terms of QCD constituents obtained from deep inelastic scatterings is related to their behaviour in soft processes. One of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. Nyiri

We derive QCD light-cone sum rules for the hadronic matrix elements of the heavy baryon transitions to nucleon. In the correlation functions the $\Lambda_c,\Sigma_c$ and $\Lambda_b$ -baryons are interpolated by three-quark currents and the…

High Energy Physics - Phenomenology · Physics 2015-05-30 A. Khodjamirian , Ch. Klein , Th. Mannel , Y. -M. Wang

I introduce and explore a range of topics of contemporary interest in hadronic physics: from what drives the formation of a nonzero quark condensate to the effect that mechanism has on light and heavy meson form factors, and the properties…

Nuclear Theory · Physics 2007-05-23 Craig D. Roberts

The research presented here uses QCD sum rules (QSR) to study exotic hadrons. There are several themes in this work. First is the use of QSR to predict the masses of exotic hadrons that may exist among the heavy quarkonium-like states. The…

High Energy Physics - Phenomenology · Physics 2014-07-10 Robin Kleiv

Off-Forward Parton Distributions (OFPD's) are new hadronic objects which may be measured in various exclusive reactions. We derive non-trivial positivity constraints for them that should allow to get extra restrictions for model inputs.

High Energy Physics - Phenomenology · Physics 2011-09-13 B. Pire , J. Soffer , O. Teryaev

We investigate the form factors for pseudoscalar-meson-photon transitions by means of dispersive QCD sum rules and demonstrate that most of the measurements done so far (in particular, those by BaBar for $\eta,$ $\eta',$ and $\eta_c$ and…

High Energy Physics - Phenomenology · Physics 2014-04-15 Wolfgang Lucha , Dmitri Melikhov

We introduce a new family of Generalised Parton Distribution models able to fulfil by construction all the theoretical properties imposed by QCD. These models are built on standard Parton Distribution Functions and extended to off-forward…

The nucleon isovector electromagnetic form factors are calculated up to next-to-next-to-leading order by combining relativistic chiral perturbation theory (ChPT) of pion, nucleon, and $\Delta$(1232) with dispersion theory. We specifically…

High Energy Physics - Phenomenology · Physics 2023-12-18 Fernando Alvarado , Di An , Luis Alvarez-Ruso , Stefan Leupold

We investigate the ten independent local form-factors relevant to the $b$-baryon decay $\Lambda_b \to \Lambda \ell^+\ell^-$, combining information of lattice QCD and dispersive bounds. We propose a novel parametrization of the form factors…

High Energy Physics - Phenomenology · Physics 2023-11-27 Thomas Blake , Stefan Meinel , Muslem Rahimi , Danny van Dyk

Using the analytic properties of two-point functions in QCD, as well as unitarity, bounds on the B meson form factor F(q^2) can be derived. Heavy quark spin symmetry, correctly taken into account, is shown to improve these bounds…

High Energy Physics - Phenomenology · Physics 2007-05-23 C. Macesanu

We present a microscopic derivation of the form factors of strong-interaction piNN and piNDelta vertices within a relativistic constituent quark model. The results are compared with form factors from phenomenological meson-baryon models and…

Nuclear Theory · Physics 2009-05-18 T. Melde , L. Canton , W. Plessas

Guided by the observed properties of hadrons I formulate a perturbative bound state method for QED and QCD. The expansion starts with valence Fock states ($e^+e^-,\ q\bar q,\ qqq,\ gg$) bound by the instantaneous interaction of temporal…

High Energy Physics - Phenomenology · Physics 2021-08-31 Paul Hoyer