English
Related papers

Related papers: Model-independent form factor relations at large $…

200 papers

Form factors are Lorentz invariant functions describing the internal structure of a system. In particular, they encode how physical properties like, e.g., charge, energy, momentum, and pressure are spatially distributed. While nucleon…

High Energy Physics - Phenomenology · Physics 2024-02-02 Cédric Lorcé

The electric dipole form factor of the nucleon stemming from the QCD $\bar{\theta}$ term is calculated in chiral perturbation theory in leading order. To this order, the form factor originates from the pion cloud. Its momentum-dependence is…

Nuclear Theory · Physics 2009-11-11 W. H. Hockings , U. van Kolck

In the large $N_c$ limit, all hyperon decays involving the same quark diagram $Q\to Q'$ are described by a single weak form factor $\eta_{QQ'}(w)$. No assumption on the mass of $Q$ or $Q'$ is necessary, making our results applicable to both…

High Energy Physics - Phenomenology · Physics 2007-05-23 Chi-Keung Chow

The chiral expansion of nucleon properties such as mass, magnetic moment, and magnetic polarizability are investigated in the framework of chiral perturbation theory, with and without the heavy-baryon expansion. The analysis makes use of a…

High Energy Physics - Phenomenology · Physics 2014-11-21 J. M. M. Hall , V. Pascalutsa

The Chiral Quark-Soliton Model of nucleons is based on two ideas: 1) the major role of spontaneous chiral symmetry breaking in hadron physics and 2) the relevance of the large number of colours limit for the real world. In these lectures I…

High Energy Physics - Phenomenology · Physics 2007-05-23 Dmitri Diakonov

We study SU(3)$_L\timesSU(3)_R$ chiral quark model of mesons up to the next to leading order of $1/N_c$ expansion. Composite vector and axial-vector mesons resonances are introduced via non-linear realization of chiral SU(3) and vector…

High Energy Physics - Phenomenology · Physics 2007-05-23 Xiao-Jun Wang , Mu-Lin Yan

The axial-vector form factor of the nucleons is considered in the framework of hard-wall model of holographic QCD. A new interaction term between the bulk gauge and matter fields was included into the interaction Lagrangian. We obtain the…

High Energy Physics - Theory · Physics 2017-05-04 Shahin Mamedov , Berin Belma Sirvanli , Ibrahim Atayev , Narmin Huseynova

The baryon Dirac form factor is computed at one-loop order in large-N_c baryon chiral perturbation theory, where N_c is the number of color charges. Loop graphs with octet and decuplet intermediate states are systematically incorporated…

High Energy Physics - Phenomenology · Physics 2015-12-09 Ruben Flores-Mendieta , Mayra Alejandra Rivera-Ruiz

The ratio of electric to magnetic proton form factors G_E/G_M as measured in polarization transfer experiments shows a characteristic linear decrease with increasing momentum transfer Q^2. We present a simple argument how such a decrease…

High Energy Physics - Phenomenology · Physics 2009-02-13 Gottfried Holzwarth

We compute the leading non-analytic correction to the baryon mass in the combined limits m_\pi -> 0, N_c -> \infty with the product m_\pi x N_c held fixed. We reproduce the results of Cohen and Broniowski using semiclassical methods rather…

High Energy Physics - Phenomenology · Physics 2009-10-28 N. Dorey , J. Hughes , M. Mattis , D. Skidmore

We consider the large N limit of three-dimensional U(N)_k Chern-Simons theory coupled to a Dirac fermion in the fundamental representation. In this limit, we compute several correlators to all orders in the `t Hooft coupling N/k. It was…

High Energy Physics - Theory · Physics 2015-06-12 Guy Gur-Ari , Ran Yacoby

Analyticity of nucleon form factors allows to derive sum rules which, using space-like and time-like data as input, can give unique information about behaviors in energy regions not experimentally accessible. Taking advantage from new…

High Energy Physics - Phenomenology · Physics 2011-09-28 S. Pacetti

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

We investigate the imaginary parts of the nucleon electromagnetic and axial form factors close to threshold in the framework of heavy baryon chiral perturbation theory. For the isovector electromagnetic form factors, we recover the well…

High Energy Physics - Phenomenology · Physics 2009-10-28 V. Bernard , N. Kaiser , Ulf-G. Meißner

We evaluate the strange nucleon electromagnetic form factors using an ensemble of gauge configurations generated with two degenerate maximally twisted mass clover-improved fermions with mass tuned to approximately reproduce the physical…

High Energy Physics - Lattice · Physics 2018-05-23 C. Alexandrou , M. Constantinou , K. Hadjiyiannakou , K. Jansen , C. Kallidonis , G. Koutsou , A. Vaquero Aviles-Casco

Using dispersive representations of the nucleon gravitational form factors, the results for their absorptive parts from chiral effective field theory in curved space-time, and the mechanical stability conditions, we obtain a model…

High Energy Physics - Phenomenology · Physics 2021-08-11 Jambul Gegelia , Maxim V. Polyakov

In electron scattering, the target form factors contribute significantly to the diffraction pattern and carry information on the target electromagnetic charge distribution. Here we show that the presence of electromagnetic radiation, as…

Atomic Physics · Physics 2015-07-28 F. Fratini , L. Safari , A. G. Hayrapetyan , K. Jänkälä , P. Amaro , J. P. Santos

Recently there has been significant interest in the macroscopic manifestation of chiral anomaly in many-body systems of chiral fermions. A notable example is the Chiral Magnetic Effect (CME). Enthusiastic efforts have been made to search…

High Energy Physics - Phenomenology · Physics 2018-02-06 Anping Huang , Yin Jiang , Shuzhe Shi , Jinfeng Liao , Pengfei Zhuang

The quasiclassical theory of massless chiral fermions is considered. The effective action is derived using time-dependent variational principle which provides a clear interpretation of relevant canonical variables. As a result their…

High Energy Physics - Theory · Physics 2019-09-04 K. Andrzejewski , Y. Brihaye , C. Gonera , J. Gonera , P. Kosiński , P. Maślanka

An expansion of the electromagnetic form factors of the nucleon and Delta(1232) in small momentum transfer and pion mass is performed in a manifestly-covariant EFT framework consistent with chiral symmetry and analyticity. We present the…

High Energy Physics - Phenomenology · Physics 2013-05-30 T. Ledwig , J. Martin-Camalich , V. Pascalutsa , M. Vanderhaeghen