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Related papers: The sigma - nucleon form factor in a chiral topolo…

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We consider the extended SU(3) Nambu and Jona-Lasinio model with explicit vector couplings in the presence of external fields. We study the chiral anomaly in this model and its implications on the properties of the nucleon described as a…

Nuclear Theory · Physics 2008-11-26 E. Ruiz Arriola , L. L. Salcedo

We investigate the form factors of the chiral-odd nucleon matrix element of the tensor current. In particular, we aim at the anomalous tensor magnetic form factors of the nucleon within the framework of the SU(3) and SU(2) chiral…

High Energy Physics - Phenomenology · Physics 2014-11-21 Tim Ledwig , Antonio Silva , Hyun-Chul Kim

We investigate the properties of different modifications to the linear $\sigma$-model (including a dilaton field associated with broken scale invariance) at finite baryon density $\rho$ and nonzero temperature $T$. The explicit breaking of…

Nuclear Theory · Physics 2008-11-26 P. Papazoglou , J. Schaffner , S. Schramm , D. Zschiesche , H. Stöcker , W. Greiner

We apply the perturbative chiral quark model at one loop to calculate the strange form factors of the nucleon. A detailed numerical analysis of the strange magnetic moments and radii of the nucleon, and also the momentum dependence of the…

High Energy Physics - Phenomenology · Physics 2009-11-07 V. E. Lyubovitskij , P. Wang , Th. Gutsche , Amand Faessler

The form factor \pi^0\gamma^*\gamma^* is obtained to the next leading order of derivative expansion of the chiral anomaly and the VMD. As a test the form factor has been used to calculate the cross section of ee^+-->\pi^0\gamma. Theory…

High Energy Physics - Phenomenology · Physics 2007-05-23 Bing An Li

The gamma -> 3 pi form factor was calculated in a simple-minded constituent model with a constant quark mass parameter, as well as in the Schwinger-Dyson approach. The comparison of these and various other theoretical results on this…

High Energy Physics - Phenomenology · Physics 2007-05-23 Dubravko Klabucar , Bojan Bistrovic

The chiral constituent quark model ($\chi$CQM) has been extended to calculate the flavor structure of the nucleon through the meson-nucleon sigma terms which have large contributions from the quark sea and are greatly affected by chiral…

High Energy Physics - Phenomenology · Physics 2015-05-28 Harleen Dahiya , Neetika Sharma

The form factor for the anomalous process $\gamma \pi ^* \to \pi \pi$, $F^{3\pi}(s,t,u)$, is calculated as a phenomenological application of the QCD Dyson-Schwinger equations. The chiral-limit value dictated by the electromagnetic,…

High Energy Physics - Phenomenology · Physics 2008-11-26 R. Alkofer , C. D. Roberts

In a conformal field theory with weakly broken higher spin symmetry, the leading order anomalous dimensions of the broken currents can be efficiently determined from the structure of the classical non-conservation equations. We apply this…

High Energy Physics - Theory · Physics 2016-12-21 Simone Giombi , Vladimir Kirilin

Chiral theories of constituent quarks interacting with bosons and photons at high temperatures are studied. In the expected chirally symmetric phase effective electromagnetic anomalous couplings for e.g. $\pi \sigma \to \gamma \gamma, ~…

High Energy Physics - Phenomenology · Physics 2007-05-23 R. Baier , M. Dirks , O. Kober

The recent investigation on various form factors of the nucleon is reviewed in the framework of the SU(3) chiral quark-soliton model. The results for the electromagnetic and scalar form factors are in remarkable agreement with experimental…

High Energy Physics - Phenomenology · Physics 2007-05-23 Hyun-Chul Kim

A model is developed for electromagnetic form factor of the pion. One-loop corrections are included in the linear sigma-model. The rho-meson contribution is added in an extended VMD model. The form factor, calculated without fitting…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. K. Dubinsky , A. Yu. Korchin , N. P. Merenkov

Theories with large mass anomalous dimensions ($\gamma_m$) have been extensively studied because of their deep consequences for models where the scalar bosons are composite. Large $\gamma_m$ values may appear when a non-Abelian gauge theory…

High Energy Physics - Phenomenology · Physics 2017-06-28 A. Doff , A. A. Natale

We use a configuration space chiral model in order to evaluate nucleon and delta sigma-terms. Analytic expressions are consistent with chiral counting rules and give rise to expected non-analytic terms in the chiral limit. We obtain the…

High Energy Physics - Phenomenology · Physics 2009-11-11 I. P. Cavalcante , M. R. Robilotta , J. Sa Borges , D. de O. Santos , G. R. S. Zarnauskas

The nucleon's strange-quark vector current form factors are studied from the perspective of chiral symmetry. It is argued that chiral perturbation theory cannot yield a prediction for the strangeness radius and magnetic moment. Arrival at…

Nuclear Theory · Physics 2009-09-25 M. J. Musolf , Hiroshi Ito

The anapole form factor of the nucleon is calculated in chiral perturbation theory to sub-leading order. This is the lowest order in which the isovector anapole form factor does not vanish. The anapole moment depends on counterterms that…

High Energy Physics - Phenomenology · Physics 2009-10-31 C. M. Maekawa , J. S. Veiga , U. van Kolck

The influence of the phi-meson on the nucleon properties in the chiral soliton model is discussed.

High Energy Physics - Phenomenology · Physics 2007-05-23 Nimai C. Mukhopadhyay , L. Zhang

The electromagnetic form factors of the nucleon have been calculated in a chiral constituent-quark model. The nucleon wave functions are obtained by solving a Schr\"odinger-type equation for a semi-relativistic Hamiltonian with an effective…

High Energy Physics - Phenomenology · Physics 2009-10-31 S. Boffi , P. Demetriou , M. Radici , R. F. Wagenbrunn

The form factor of the vector meson V conversion transition into the pseudoscalar meson P and the lepton pair l+l- is presented for V=rho0,omega,phi and P=pi0,eta. Our approach is based on the chiral effective field theory with resonances.…

High Energy Physics - Phenomenology · Physics 2012-03-06 Sergiy Ivashyn

Using heavy baryon chiral perturbation theory to one loop, we derive an analytic and parameter-free expression for the momentum dependence of the strange magnetic form factor of the nucleon $G_M^{(s)} (Q^2)$ and its corresponding radius.…

High Energy Physics - Phenomenology · Physics 2009-10-31 T. R. Hemmert , Ulf-G. Meißner , S. Steininger