English
Related papers

Related papers: Valence quark and meson cloud contributions for th…

200 papers

High-precision nucleon-resonance electroproduction data on a large kinematic domain of energy and momentum transfer have proven crucial in revealing novel features of strong interactions within the Standard Model and unfolding structural…

Nuclear Theory · Physics 2019-02-27 Chen Chen , Ya Lu , Daniele Binosi , Craig D. Roberts , Jose Rodríguez-Quintero , Jorge Segovia

By applying a unitary transformation method, we have derived the leading-order corrections on the effective Hamiltonian of a dynamical model developed in Phys. Rev. C54, 2660 (1996) for electromagnetic pion production reactions. The…

Nuclear Theory · Physics 2007-05-23 T. Sato , T. -S. H. Lee , T. Nakamura

We calculate the weak transition form factors of the $\Lambda_b\to\Lambda(1520)$ transition, and further calculate the angular distributions of the rare decays $\Lambda_b\to\Lambda(1520)(\to N\bar{K})\ell^{+}\ell^{-}$…

High Energy Physics - Phenomenology · Physics 2023-05-12 Yu-Shuai Li , Su-Ping Jin , Jing Gao , Xiang Liu

The photoproduction p(gamma, K+)Lambda process is studied within a field-theoretic approach. It is shown that the background contributions constitute an important part of the reaction dynamics. We compare predictions obtained with three…

Nuclear Theory · Physics 2008-11-26 S. Janssen , J. Ryckebusch , D. Debruyne , T. Van Cauteren

A parameter-free evaluation of the $N - \Delta$ electromagnetic transition form factors is carried out in a light-front constituent quark model, based on $N$ and $\Delta$ eigenstates of a mass operator which reproduces a large set of hadron…

Nuclear Theory · Physics 2009-10-28 F. Cardarelli , E. Pace , G. Salme' , S. Simula

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

We review recent experimental and theoretical results for the electromagnetic form factors of hyperons (Y) in the timelike region, accessible in the reactions $e^+e^-\to \bar YY$. Specifically, we focus on the final states $\bar…

High Energy Physics - Phenomenology · Physics 2024-12-11 Ling-Yun Dai , Johann Haidenbauer , Ulf-G. Meißner

We study the $\eta$ and $\eta'$ distribution amplitudes (DAs) in the context of a nonlocal SU(3)_L x SU(3)_R chiral quark model. The corresponding Lagrangian allows to reproduce the phenomenological values of pseudoscalar meson masses and…

High Energy Physics - Phenomenology · Physics 2017-03-15 D. Gomez Dumm , S. Noguera , N. N. Scoccola

A synopsis exemplifying the employment of Dyson-Schwinger equations in the calculation and explanation of hadron electromagnetic form factors and related phenomena. In particular the contribution: presents the pion form factor computed…

Nuclear Theory · Physics 2009-02-19 I. C. Cloet , C. D. Roberts

We study the vector, scalar and tensor form factors for the semileptonic process $D\rightarrow K$ by using lattice Quantum Chromodynamcs (QCD). Chiral lattice fermions are used in our study: overlap fermion for the valence quark and…

High Energy Physics - Lattice · Physics 2025-03-04 Tinghong Shen , Ying Chen , Ming Gong , Dong-Hao Li , Keh-Fei Liu , Zhaofeng Liu , Zhenyu Zhang

The long-range $\Lambda N-\Sigma N$ interaction is modeled by a configuration space meson-exchange potential matrix coupling to channels with $\Delta$ and $\Sigma(1385)$ isobars. An inner boundary condition, based on $R$-matrix theory,…

Nuclear Theory · Physics 2009-10-22 W. R. Greenberg , E. L. Lomon

The meson-cloud model of the nucleon consisting of a system of three valence quarks surrounded by a meson cloud is applied to study the electroweak structure of the proton and neutron. The electroweak nucleon form factors are calculated…

High Energy Physics - Phenomenology · Physics 2015-05-13 B. Pasquini , S. Boffi

Electromagnetic form factors serve to explore the intrinsic structure of nucleons and their strangeness partners. For the decay $\Sigma^0\to\Lambda e^+e^-$, due to limited phase space, the effects caused by the Sigma-to-Lambda transition…

High Energy Physics - Phenomenology · Physics 2021-01-01 Tomáš Husek

The covariant spectator quark model, tested before in a variety of electromagnetic baryon excitations, is applied here to the $\gamma^\ast N \to N^\ast(1520)$ reaction in the timelike regime. The transition form factors are first…

Nuclear Theory · Physics 2017-01-10 G. Ramalho , M. T. Peña

We investigate the structure of the Lambda(1405) resonance and Kbar N phenomenology in the perspective of chiral SU(3) dynamics. Utilizing the chiral coupled-channel approach which well describes the Kbar N scattering observable, we perform…

Nuclear Theory · Physics 2009-12-17 Tetsuo Hyodo

We apply a modified vector meson dominance (VMD) model to analyze the electromagnetic form factors of the $\Lambda_c$ hyperon in the time-like reaction $e^+e^-\rightarrow \Lambda_c^+ \bar{\Lambda}_c^-$. In the model, we include the…

High Energy Physics - Phenomenology · Physics 2021-10-19 Junyao Wan , Yongliang Yang , Zhun Lu

In this two part series a chiral confining model of baryons is used to describe low--lying negative parity resonances $N^*$, $\Delta^*$, $\Lambda^*$ and $\Sigma^*$ in the mean field approximation. A physical baryon in this model consists of…

Nuclear Theory · Physics 2007-05-23 Y. Umino , M. K. Banerjee

We investigate the rare decay $\Lambda_b \to \Lambda \gamma$ which receives both short and long distance contributions. We estimate the long distance contributions and find them very small. The form factors are obtained from $\Lambda_c \to…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. Mannel , S. Recksiegel

The $\gamma \gamma^\ast \to \eta_{c,b}$ transition form factors are computed using a continuum approach to the two valence-body bound-state problem in relativistic quantum field theory, and thereby unified with equivalent calculations of…

Nuclear Theory · Physics 2017-04-19 Khepani Raya , Minghui Ding , Adnan Bashir , Lei Chang , Craig D. Roberts

The inclusion of two-body exchange currents in the constituent quark model leads to new relations between the electromagnetic properties of octet and decuplet baryons. In particular, the N->Delta quadrupole transition form factor can be…

High Energy Physics - Phenomenology · Physics 2009-02-24 A. J. Buchmann
‹ Prev 1 4 5 6 7 8 10 Next ›