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Related papers: Timelike gamma* N -> Delta form factors and Delta …

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Lattice results on the N to Delta electromagnetic, axial-vector and pseudoscalar form factors are evaluated using dynamical staggered sea quarks and domain wall valence quarks for pion masses in the range of 580-350 MeV, as well as,…

High Energy Physics - Lattice · Physics 2017-08-23 C. Alexandrou

We present calculations for \Delta excitation in the (K^+,K^+) reaction in nuclei. The background from quasielastic K^+ scattering in the \Delta region is also evaluated and shown to be quite small in some kinematical regions, so as to…

Nuclear Theory · Physics 2008-11-26 J. A. Oller , E. Oset , A. De Pace , P. Fernandez de Cordoba

We evaluate the N to Delta axial transition form factors in lattice QCD in the quenched theory, with two degenerate flavors of dynamical Wilson fermions and using domain wall valence fermions with staggered sea quark configurations. We…

High Energy Physics - Lattice · Physics 2008-11-26 C. Alexandrou , Th. Leontiou , J. W. Negele , A. Tsapalis

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

The reaction $e^+e^- \to \bar \Lambda \Lambda$ is investigated for energies close to the threshold. Specific emphasis is put on the role played by the interaction in the final $\bar \Lambda \Lambda$ system which is taken into account…

Nuclear Theory · Physics 2016-10-12 J. Haidenbauer , U. -G. Meißner

The reaction mechanisms for $K\Sigma(1385)$ photoproduction from the reaction $\gamma p \to K^+\Sigma^{0}(1385)$ in the resonance energy region are investigated in a hadronic model. Both contributions from $N$ and $\Delta$ resonances of…

Nuclear Theory · Physics 2008-11-26 Yongseok Oh , Che Ming Ko , K. Nakayama

The electromagnetic form factors $G_{\rm E}$ and $G_{\rm M}$ of the proton and neutron in the timelike region are extracted in a study of the processes $e^+ e^-\to \bar{p}p$ and $e^+ e^-\to \bar{n}n$. The reaction amplitude is evaluated…

Nuclear Theory · Physics 2024-04-22 Qin-He Yang , Di Guo , Ming-Yan Li , Ling-Yun Dai , Johann Haidenbauer , Ulf-G. Meißner

The $\eta$ transition form factor is analysed for the first time in both space- and time-like regions at low and intermediate energies in a model-independent approach through the use of rational approximants. The $\eta\rightarrow…

High Energy Physics - Phenomenology · Physics 2015-09-17 R. Escribano , P. Masjuan , P. Sanchez-Puertas

The KLOE results on the measurement of the transition form factors of the eta and pi0 mesons in phi Dalitz decays are presented, and the determination of the Gamma(eta->gamma gamma) in gamma gamma processes is also reported. The prospects…

High Energy Physics - Experiment · Physics 2019-08-14 Paolo Gauzzi

Using the non-relativistic effective field theory framework in a finite volume, we discuss the extraction of the $\Delta N\gamma^*$ transition form factors from lattice data. A counterpart of the L\"uscher approach for the matrix elements…

High Energy Physics - Lattice · Physics 2016-05-12 Andria Agadjanov , Véronique Bernard , Ulf-G. Meißner , Akaki Rusetsky

A covariant spectator quark model is applied to study the gamma N -> N*(1535) reaction in the large Q2 region. Starting from the relation between the nucleon and N*(1535) systems, the N*(1535) valence quark wave function is determined…

High Energy Physics - Phenomenology · Physics 2012-04-30 G. Ramalho , M. T. Pena , K. Tsushima

We develop techniques to calculate the four Delta electromagnetic form factors using lattice QCD, with particular emphasis on the sub-dominant electric quadrupole form factor that probes deformation of the Delta. Results are presented for…

High Energy Physics - Lattice · Physics 2010-04-21 C. Alexandrou , T. Korzec , G. Koutsou , Th. Leontiou , C. Lorcé , J. W. Negele , V. Pascalutsa , A. Tsapalis , M. Vanderhaeghen

We present the results on the ratios $E_{1+}^{(3/2)}/M_{1+}^{(3/2)}$ and $S_{1+}^{(3/2)}/M_{1+}^{(3/2)}$ for the $\gamma^* N \to \Delta(1232)$ transition at $Q^2\leq 4 (GeV/c)^2$ extracted from the $p(e,e'p)\pi^0$ cross section using two…

Nuclear Theory · Physics 2017-08-23 I. G. Aznauryan

The reactions ppbar -> e+e- and e+e- -> ppbar are analyzed in the near-threshold region. Specific emphasis is put on the role played by the interaction in the initial- or final antinucleon-nucleon state which is taken into account…

Nuclear Theory · Physics 2014-07-22 J. Haidenbauer , X. -W. Kang , U. -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

Starting with a spectator quark model developed for the nucleon (N) and the Delta in the physical pion mass region, we extend the predictions of the reaction gamma N -> Delta to the lattice QCD regime. The quark model includes S and D waves…

High Energy Physics - Phenomenology · Physics 2010-04-15 G. Ramalho , M. T Pena

The recently developed formalism for the evaluation of nuclear form factors in neutrinoless double beta decay is applied to $^{48}Ca$, $^{76}Ge$, $^{82}Se$, $^{100}Mo$, $^{128}Te$ and $^{130}Te$ nuclei. Explicit analytical expressions that…

Nuclear Theory · Physics 2009-10-31 C. Barbero , F. Krmpotić , A. Mariano , D. Tadić

The cross-sections of the $\gamma p-\gamma' N'$, $\gamma p-\pi' N'$ and $\gamma p-\gamma'\pi' N'$ reactions are calculated in the framework of the field-theoretical one-particle ($\pi,\omega,\rho$-mesons, nucleon and $\Delta$-resonance)…

Nuclear Theory · Physics 2007-05-23 A. I. Machavariani , Amand Faessler

We present recent lattice QCD results on the electroweak nucleon to $\Delta$ transition and $\Delta$ form factors using dynamical fermion gauge configurations with a lowest pion mass of about 300 MeV, with special emphasis in the…

High Energy Physics - Lattice · Physics 2019-08-15 Constantia Alexandrou

In this work, the radiative Bc -> D*_s gamma decay is investigated in the framework of QCD sum rules. The transition form factors responsible for the decay are calculated. The branching ratio for this decay is estimated to be order of 10^-5…

High Energy Physics - Phenomenology · Physics 2009-11-13 K. Azizi , V. Bashiry