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We study the influence of non-valence quark-pair contributions in weak transition form factors of heavy-light mesons. Form factors are first calculated for spacelike momentum transfers in a reference frame where such contributions are…

High Energy Physics - Phenomenology · Physics 2022-02-10 María Gómez-Rocha , Oliver Heger , Wolfgang Schweiger

Building on our successful technique to isolate the otherwise-elusive $\Lambda$(1405) using correlation matrix techniques and multiple source and sink smearings, we present calculations of the quark sector contributions to the electric form…

High Energy Physics - Lattice · Physics 2013-11-21 Benjamin J. Menadue , Waseem Kamleh , Derek B. Leinweber , M. Selim Mahbub , Benjamin J. Owen

A theoretical framework is suggested for the calculation of gamma* N -> Delta transition form factors using the light-cone sum rule approach. Leading-order sum rules are derived and compared with the existing experimental data. We find that…

High Energy Physics - Phenomenology · Physics 2014-11-18 V. M. Braun , A. Lenz , G. Peters , A. V. Radyushkin

We analyse the angular distributions of the Sigma^0 --> Lambda^0 + gamma decay rate in the laboratory and in the rest frame of the Sigma^0 - hyperon in the dependence on baryon polarizations. We calculate the dynamical polarization vector…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. N. Ivanov , A. Ya. Berdnikov , Ya. A. Berdnikov , M. Faber , V. A. Ivanova , V. F. Kosmach , A. V. Nikitchenko , N. I. Troitskaya

We analyze the electromagnetic form factors of the ground state baryon octet to fourth order in relativistic baryon chiral perturbation theory. Predictions for the \Sigma^- charge radius and the \Lambda-\Sigma^0 transition moment are found…

High Energy Physics - Phenomenology · Physics 2009-01-07 Bastian Kubis , Ulf-G. Meißner

Without any further adjusting of parameters, a relativistic constituent quark model, successful in the description of the data for the nucleon elastic form factors and of the dominant contribution for the nucleon to Delta electromagnetic…

High Energy Physics - Phenomenology · Physics 2009-07-24 G. Ramalho , M. T. Pena

An important goal of ongoing and future experiments is to explore spectra and transition form factors of baryons with non-zero strangeness. Of particular interest is the transition form factor$\gamma^{(*)} \Sigma^0 \rightarrow \Lambda$ in…

High Energy Physics - Phenomenology · Physics 2024-04-16 Langtian Liu , Christian S. Fischer

Using dispersion theory, the electromagnetic Sigma-to-Lambda transition form factors are expressed as the product of the pion electromagnetic form factor and the $\Sigma\bar{\Lambda}\to\pi\pi$ scattering amplitudes with the latter estimated…

High Energy Physics - Phenomenology · Physics 2023-04-05 Yong-Hui Lin , Hans-Werner Hammer , Ulf-G. Meißner

In this work, the electromagnetic and gravitational form factors of $\Delta$ isobars, as well as the electromagnetic $N-\Delta$ transition form factors are studied systematically and continuously using a covariant quark-diquark approach…

High Energy Physics - Phenomenology · Physics 2026-02-24 Jiaqi Wang , Dongyan Fu , Yubing Dong

We calculate magnetic moments of light baryons and N -> Delta gamma transition characteristics using a manifestly Lorentz covariant chiral quark approach for the study of baryons as bound states of constituent quarks dressed by a cloud of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Amand Faessler , Thomas Gutsche , Barry R. Holstein , Valery E. Lyubovitskij , Diana Nicmorus , Kem Pumsa-ard

The form factors of $\gamma^* N \rightarrow \Delta(1600)$ transition is calculated within the light-cone sum rules assuming that $\Delta^+(1600)$ is the first radial excitation of $\Delta(1232)$. The $Q^2$ dependence of the magnetic dipole…

High Energy Physics - Phenomenology · Physics 2020-07-01 T. M. Aliev , T. Barakat , S. Bilmis , M. Savci

The internal structure of the resonant Lambda(1405) state is investigated based on meson-baryon coupled-channels chiral dynamics, by evaluating density distributions obtained from the form factors of the Lambda(1405) state. The form factors…

Nuclear Theory · Physics 2015-03-17 Takayasu Sekihara , Tetsuo Hyodo , Daisuke Jido

Results for the reaction gamma p --> K+ Lambda, studied within a constituent quark model and a dynamical coupled-channel approach, are presented and compared with recent data. Issues related to the search for missing baryon resonances are…

Nuclear Theory · Physics 2016-08-16 B. Juliá-Díaz , B. Saghai , F. Tabakin , W. -T. Chiang , T. -S. H. Lee , Z. Li

We present a unified Quantum Chromodynamics (QCD)-based description of elastic and transition electromagnetic form factors involving the nucleon and its resonances. We compare predictions made using a framework built upon a Faddeev equation…

Nuclear Theory · Physics 2018-07-04 Jorge Segovia

We discuss $(\pi^0,\eta,\eta')\to\gamma^*\gamma$ transition form factors using the light-front quark model. Our discussion includes the analysis of the mixing angles for $\eta-\eta'$. Our results for $Q^2…

High Energy Physics - Phenomenology · Physics 2016-03-23 Ho-Meoyng Choi , Chueng-Ryong Ji

A recently developed non-perturbative chiral approach to dynamically generate the (3/2^-) baryon resonances has been extended to investigate the radiative decays Lambda^*(1520) --> gamma Lambda(1116) and Lambda^*(1520) --> gamma…

Nuclear Theory · Physics 2008-11-26 M. Doring , E. Oset , Sourav Sarkar

The electromagnetic and axial form factors of the nucleon and its lowest positive parity excitations, the Delta(1232) and the N*(1440), are calculated with constituent-quark models that are specified by simple algebraic representations of…

High Energy Physics - Phenomenology · Physics 2014-11-17 B. Julia-Diaz , D. O. Riska , F. Coester

We use light-front Holography to estimate the valence quark and the meson cloud contributions to the nucleon axial form factor. The free couplings of the holographic model are determined by the empirical data and by the information…

High Energy Physics - Phenomenology · Physics 2018-04-16 G. Ramalho

The light-quark sector of the Lambda(1405) baryon is examined in the context of the recent discovery of a dominant antikaon-nucleon composition at low quark masses. Further evidence for this interpretation of the Lambda(1405) is presented,…

High Energy Physics - Lattice · Physics 2017-03-30 Jonathan M. M. Hall , Waseem Kamleh , Derek B. Leinweber , Benjamin J. Menadue , Benjamin J. Owen , Anthony W. Thomas

We study the N-Delta-gamma transition in the Dyson-Schwinger approach. The nucleon and Delta baryons are treated as quark-diquark bound states, where the ingredients of the electromagnetic transition current are computed self-consistently…

High Energy Physics - Phenomenology · Physics 2013-05-30 Gernot Eichmann , Diana Nicmorus