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Related papers: Vector Meson Dominance and Free Quarks

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We study a model-independent parameterization of the vector pion form factor that arises from the constraints of analyticity and unitarity. Our description should be suitable up to sqrt(s) ~ 1.2 GeV and allows a model-independent…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Pich , J. Portoles

The vector dominance of the electromagnetic form factors both for mesons and baryons arises naturally in holographic QCD, where both the number of colors and the 't Hooft coupling are taken to be very large, offering a bona-fide derivation…

High Energy Physics - Phenomenology · Physics 2008-11-26 Deog Ki Hong , Mannque Rho , Ho-Ung Yee , Piljin Yi

Motivated by the planned measurements of the time-like electromagnetic proton form factors an exploratory study of the time-like electromagnetic pion form factor is presented in a formalism which describes mesons as Poincar\'e-invariant…

High Energy Physics - Phenomenology · Physics 2022-07-20 Reinhard Alkofer , Angel S. Miramontes , Helios Sanchis-Alepuz

We present a procedure to derive a covariant electromagnetic current operator for a system made up by two scalars constituents. Using different wave functions we fitted their parameters to the experimental data of the pion form factor,…

Nuclear Theory · Physics 2007-05-23 Mario A. Acero , Maurizio De Sanctis , Carlos E. Sandoval

I show comparisons of the pseudoscalar meson vector form factor from simulations of QCD with $N_c = 3$, 4 and 5 colors and $N_f = 2$ flavors of degenerate mass fermions at a common (matched) fermion mass, lattice spacing, and simulation…

High Energy Physics - Lattice · Physics 2024-12-19 Thomas DeGrand

Using a ladder-rainbow kernel previously established for light quark hadron physics, we explore the extension to masses and electroweak decay constants of ground state pseudoscalar and vector quarkonia and heavy-light mesons in the c- and…

Nuclear Theory · Physics 2015-05-13 T. Nguyen , N. A. Souchlas , P. C. Tandy

We study phenomenological aspects of the holographic model of chiral symmetry breaking recently introduced by Kuperstein and Sonnenschein (KS). As a first step, we calculate the spectrum of vector and axial-vector mesons in the KS model. We…

High Energy Physics - Theory · Physics 2011-03-28 C. A. Ballon Bayona , Henrique Boschi-Filho , Matthias Ihl , Marcus A. C. Torres

The renormalizable Abelian quantum field theory model of Kroll, Lee, and Zumino is used to compute the one-loop vertex corrections to the tree-level, Vector Meson Dominance (VMD) pion form factor. These corrections, together with the known…

High Energy Physics - Phenomenology · Physics 2008-11-26 Cesareo A. Dominguez , Juan I. Jottar , Marcelo Loewe , Bernard Willers

The vector form factor of the pion is calculated in the framework of chiral effective field theory with vector mesons included as dynamical degrees of freedom. To construct an effective field theory with a consistent power counting, the…

High Energy Physics - Phenomenology · Physics 2015-06-23 D. Djukanovic , J. Gegelia , A. Keller , S. Scherer , L. Tiator

Pion transition form factor for the process $\gamma*\gamma*\to \pi^0$ at space-like values of photon momenta is calculated within the effective quark-meson model with the interaction induced by instanton exchange. The leading and…

High Energy Physics - Phenomenology · Physics 2014-11-17 A. E. Dorokhov

We extend our previous formulation of low-energy QCD in terms of an effective lagrangian containing operators of dimensionality $d\le 6$ constructed with pseudoscalars and quark fields, describing physics below the scale of chiral symmetry…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. A. Andrianov , D. Espriu

Measurements and theoretical calculations of meson form factors are essential for our understanding of internal hadron structure and QCD, the dynamics that bind the quarks in hadrons. The pion electromagnetic form factor has been measured…

High Energy Physics - Lattice · Physics 2018-04-18 Jonna Koponen , André Zimermmane-Santos , Christine Davies , G. Peter Lepage , Andrew Lytle

The elastic and transition electromagnetic form factors of mesons are investigated within a light-front constituent quark model. The general formulae for the space-like matrix elements of the one-body component of the electromagnetic…

Nuclear Theory · Physics 2011-04-15 F. Cardarelli , I. L. Grach , I. M. Narodetskii , G. Salme' , S. Simula

We have reexamined the elastic pion form factor over a broad range of momentum transfers with the mass evolution from current quark to constituent quark being taken into account. We have also studied the effect of Sudakov form factors, of…

High Energy Physics - Phenomenology · Physics 2016-09-01 Leonard S. Kisslinger , Siwen Wang

The behavior of the transition pion form factor for processes \gamma^*\gamma -> \pi^0 and \gamma^* \gamma^* -> \pi^0 at large values of space-like photon momenta is estimated within the nonlocal covariant quark-pion model. It is shown that,…

High Energy Physics - Phenomenology · Physics 2009-10-31 I. V. Anikin , A. E. Dorokhov , Lauro Tomio

The vector meson mass is computed as a function of quark mass in the large N limit of QCD. We use continuum reduction and directly compute the vector meson propagator in momentum space. Quark momentum is inserted using the quenched momentum…

High Energy Physics - Lattice · Physics 2009-11-13 A. Hietanen , R. Narayanan , R. Patel , C. Prays

We study the pion form factor in a broad range of spacelike momentum transfers within the local-duality version of QCD sum rules. We make use of the recently calculated two-loop double spectral density of the $<AVA>$ correlator including…

High Energy Physics - Phenomenology · Physics 2008-11-26 Victor Braguta , Wolfgang Lucha , Dmitri Melikhov

The role of effective degrees of freedom on the vector and axial-vector susceptibilities and the pion velocity at chiral restoration is analyzed. We consider two possible scenarios, one in which pions are considered to be the only low-lying…

High Energy Physics - Phenomenology · Physics 2009-11-10 Mannque Rho

We present results on the Omega baryon electromagnetic form factors using $N_f=2+1$ domain-wall fermion configurations for three pion masses in the range of about 350 to 300 MeV. We compare results obtained using domain wall fermions with…

High Energy Physics - Lattice · Physics 2014-11-21 C. Alexandrou , T. Korzec , G. Koutsou , J. W. Negele , Y. Proestos

We analyse the pion electromagnetic, charged-current, and $\pi\gamma$ transition form factors at timelike momentum transfers $q$, $q^2=s\le 1.4$ GeV$^2$, using a dispersion approach. We discuss in detail the propagator matrix of the…

High Energy Physics - Phenomenology · Physics 2009-11-10 D. Melikhov , O. Nachtmann , V. Nikonov , T. Paulus