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Related papers: Timelike Form Factors

200 papers

Selected topics related to the physics of the energy-momentum tensor (EMT) form factors are discussed. The topics are: 1) Fundamental mechanical properties of particles and gravity 2) Mechanical properties of non-spherical particles 3)…

High Energy Physics - Phenomenology · Physics 2018-12-18 Maxim V. Polyakov , Peter Schweitzer

The comparison of magnetic moment of neutron and proton enables to outline qualitatively the structure of nucleon by using a model similar to the one suggested by Ida and Kobayashi that "baryons consist of a qq pair (or a diquark) and…

Astrophysics · Physics 2007-05-23 A. V. Kopylov

We compute electroweak form factors of the nucleon and photon transition form factors of non-strange baryon resonances up to the third resonance region in a model with instanton-induced interaction. The calculation is based on the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Dirk Merten , Ulrich Loering , Klaus Kretzschmar , Bernard Metsch , Herbert-R. Petry

The chiral quark model posits pseudoscalar and vector meson couplings to constituent quarks. The parity violating meson-quark couplings lead to anapole moments and form factors of the nucleons. These arise both as parity violating meson…

High Energy Physics - Phenomenology · Physics 2009-10-31 D. O. Riska

With a special intention of clarifying the underlying spin contents of the nucleon, we investigate the generalized form factors of the nucleon, which are defined as the $n$-th $x$-moments of the generalized parton distribution functions,…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Wakamatsu , Y. Nakakoji

The electromagnetic and axial form factors of the nucleon are evaluated in twisted mass QCD with two degenerate flavors of light, dynamical quarks. The axial charge g_A, magnetic moment and the Dirac and Pauli radii are determined for pion…

Searches for new physics using muons are reviewed. Particular attention is paid to muon number non-conserving processes, like the decay muon-->e+gamma and muon-electron conversion in muonic atoms. Also, experimental determinations and…

High Energy Physics - Phenomenology · Physics 2009-10-30 Andrzej Czarnecki

We study the transition form factors of the pesudoscalar mesons ($\pi,\eta$ and $\eta^{\prime}$) as functions of the momentum transfer $Q^2$ within the light-front quark model. We compare our results with the recent experimental data by…

High Energy Physics - Phenomenology · Physics 2015-06-11 Chao-Qiang Geng , Chong-Chung Lih

We study contributions to the nucleon strange quark vector current form factors from intermediate states containing K^* mesons. We show how these contributions may be comparable in magnitude to those made by K mesons, using methods…

High Energy Physics - Phenomenology · Physics 2009-10-31 L. L. Barz , H. Forkel , H. -W. Hammer , F. S. Navarra , M. Nielsen , M. J. Ramsey-Musolf

We consider the light-front holographic QCD with the light-front wave functions for mesons, modified for massive quarks. We evaluate the wave functions, distribution amplitudes, and form factors for $\pi$, $\rho$, $K$, and $J/\psi$ mesons…

High Energy Physics - Phenomenology · Physics 2015-10-19 Rohit Swarnkar , Dipankar Chakrabarti

We present a simultaneous analysis of elastic and transition form factors of the nucleon. The calculations are performed in the framework of an algebraic model of baryons. Effects of meson cloud couplings are considered.

Nuclear Theory · Physics 2007-05-23 R. Bijker , A. Leviatan

To know and understand form factors of hadronic currents is of decisive importance for analysing exclusive weak decays. The ratios of different form factors of a given process depend on the relativistic spin structure of initial and final…

High Energy Physics - Phenomenology · Physics 2011-07-19 B. Stech

Longitudinal and transverse quark momentum distributions in the nucleon are calculated from a phenomenological quark-nucleon vertex function obtained through an investigation of the nucleon electromagnetic form factors within a light-front…

High Energy Physics - Phenomenology · Physics 2014-11-20 E. Pace , J. P. B. C. de Melo , T. Frederico , S. Pisano , G. Salme'

The present-day experimental situation concerning nucleon form factors in the space-like region shows a substantial discrepancy between measurements via the Rosenbluth method and the recoil polarisation technique. More information about…

High Energy Physics - Phenomenology · Physics 2007-05-23 E. Nowak

We analyze the form factors of the electromagnetic nucleon-to-Roper-resonance transition in the framework of low-energy effective field theory. A systematic power-counting procedure is generated by applying the complex-mass scheme. Within…

Nuclear Theory · Physics 2015-06-18 T. Bauer , S. Scherer , L. Tiator

The electromagnetic form factors of the nucleon are calculated in an extended chiral constituent-quark model where the effective interaction is described by the exchange of pseudoscalar, vector, and scalar mesons. Two-body current-density…

High Energy Physics - Phenomenology · Physics 2007-05-23 P. Demetriou , S. Boffi , M. Radici , R. F. Wagenbrunn

By means of QCD sum rules in local-duality limit, we analyze the behaviour of the form factors for the transitions of a real and a virtual photon to some pseudoscalar meson as functions of the involved momentum transfer. Except for the…

High Energy Physics - Phenomenology · Physics 2012-12-27 Irina Balakireva , Wolfgang Lucha , Dmitri Melikhov

The form factors for the transitions pi-photon, eta-photon, eta'-photon and etac-photon are analyzed within the modified perturbative approach in which quark transverse degrees of freedom are retained. The results for the form factors are…

High Energy Physics - Phenomenology · Physics 2025-01-09 P. Kroll

We present a combined analysis of the electromagnetic form factors of the nucleon in the space- and timelike regions using dispersion theory. Our framework provides a consistent description of the experimental data over the full range of…

High Energy Physics - Phenomenology · Physics 2022-02-16 Yong-Hui Lin , Hans-Werner Hammer , Ulf-G. Meißner

We update a recent dispersion--theoretical fit to the nucleon electromagnetic form factors by including the existing data in the time--like region. We show that while the time--like data for the proton can be described consistently with the…

High Energy Physics - Phenomenology · Physics 2009-10-28 H. -W. Hammer , Ulf-G. Meißner , D. Drechsel