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Related papers: Watson's theorem and the $N\Delta(1232)$ axial tra…

200 papers

We show that a recent claim (H.Haberzettl, Phys. Rev. Lett. 85 (2000) 3576) that one cannot extract the nucleon weak axial form factor G_A (t) from charged pion threshold electroproduction is incorrect. Thus previous calculations remain…

High Energy Physics - Phenomenology · Physics 2007-05-23 V. Bernard , N. Kaiser , 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

The electromagnetic, axial and pseudoscalar nucleon to Delta form factors are calculated using dynamical domain wall fermions at a lattice spacing of a = 0.114 fm on a lattice of spatial size 2.74 fm and pion mass of 331 MeV. Pion pole…

High Energy Physics - Lattice · Physics 2010-11-05 C. Alexandrou , G. Koutsou , J. W. Negele , A. O'Cais , Y. Proestos , A. Tsapalis

The form-factors for the transition $ N^*(1535)\to N $ induced by isovector and isoscalar axial currents within the framework of light-cone QCD sum rules by using the most general form of the interpolating current are calculated. In…

High Energy Physics - Phenomenology · Physics 2019-10-02 T. M. Aliev , T. Barakat , K. Simsek

We derive novel low--energy theorems for single pion production off nucleons through the isovector axial current. We find that the $k^2$-dependence of the multipole $L_{0+}^{(+)}$ at threshold is given by the nucleon scalar form factor,…

High Energy Physics - Phenomenology · Physics 2011-07-19 V. Bernard , N. Kaiser , Ulf-G. Meißner

Neutrino-induced productions (neutrinoproduction) of photons and pions from nucleons and nuclei are important for the interpretation of neutrino-oscillation experiments, as they are potential backgrounds in the MiniBooNE experiment [A. A.…

Nuclear Theory · Physics 2012-09-28 Brian D. Serot , Xilin Zhang

Heavy baryon chiral perturbation theory ($\chi$PT), where the $\Delta$ resonance is included, is used in order to examine the axial charged-current component of the weak interaction process at low neutrino energies. At leading chiral order…

Nuclear Theory · Physics 2019-03-13 Fred Myhrer

The charge changing weak production of Delta in nucleons and nuclei is studied. The reactions e^{-} p -> Delta^{0} \nu_{e} and e^{+} p -> Delta^{++} \bar{\nu}_{e} are considered as a possible source of information about the weak N-Delta…

Nuclear Theory · Physics 2011-02-09 L. Alvarez-Ruso , E. Oset , S. K. Singh , M. J. Vicente Vacas

Predictions obtained with a confining, symmetry-preserving treatment of a vector-vector contact interaction at leading-order in a widely used truncation of QCD's Dyson-Schwinger equations are presented for \Delta and \Omega baryon elastic…

Single pion production in neutrino-nucleon scattering is discussed. The neutrino energies characteristic for T2K project are considered. Two new parameterizations of $C_5^A$ axial form factor are proposed. Both of them are obtained in…

High Energy Physics - Phenomenology · Physics 2008-10-08 Krzysztof M. Graczyk

The neutrino pion production off the nucleon is traditionally described in the literature by means of the weak excitation of the Delta(1232) resonance and its subsequent decay into N pi. Here, we present results from a model that includes…

High Energy Physics - Experiment · Physics 2008-11-26 E. Hernandez , J. Nieves , M. Valverde

The process of pion axioproduction, $aN\to\pi N$, with an intermediate $\Delta$ resonance is analyzed using baryon chiral parturbation theory. The $\Delta$ resonance is included in two ways: First, deriving the $a\Delta N$-vertices, the…

High Energy Physics - Phenomenology · Physics 2022-03-30 Thomas Vonk , Feng-Kun Guo , Ulf-G. Meißner

Recent experiment indicates that the behavior exhibited by the ratios $E_{1^+}/M_{1^+}$ and $S_{1^+}/M_{1^+}$ of the $\gamma^* N \leftrightarrow \Delta$ transition remain small and negative for $Q^2 \le 4.0 GeV^2$. It implies that the…

Nuclear Theory · Physics 2010-04-06 S. S. Kamalov , Shin Nan Yang

We develop an extension of chiral perturbation theory to the $\Delta$(1232)-resonance energy region and apply it to investigate the pion electroproduction off the nucleon ($e^- N \to e^- N\pi$). We present a complete calculation of this…

High Energy Physics - Phenomenology · Physics 2008-11-26 Vladimir Pascalutsa , Marc Vanderhaeghen

A quark model relation between the neutron charge form factor and the N->Delta charge quadrupole form factor is used to predict the C2/M1 ratio in the N->Delta transition from the elastic neutron form factor data. Excellent agreement with…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. J. Buchmann

Vector and axial form factors in the quark resonance model are analyzed with a combination of theoretical and phenomenological arguments. The new form of form factors is deduced from $\Delta$(1232) excitation models and available data. The…

High Energy Physics - Phenomenology · Physics 2014-11-18 K. M. Graczyk , J. T. Sobczyk

We use a continuum quark+diquark approach to the nucleon bound-state problem in relativistic quantum field theory to deliver parameter-free predictions for the nucleon axial and induced pseudoscalar form factors, $G_A$ and $G_P$, and unify…

High Energy Physics - Phenomenology · Physics 2022-06-01 Chen Chen , Christian S. Fischer , Craig D. Roberts , Jorge Segovia

A careful reanalysis of both Argonne National Laboratory and Brookhaven National Laboratory data for weak single pion production is done. We consider deuteron nuclear effects and normalization (flux) uncertainties in both experiments. We…

High Energy Physics - Phenomenology · Physics 2009-11-10 K. M. Graczyk , D. Kielczewska , P. Przewlocki , J. T. Sobczyk

In this work, we extend the analysis of the pion axioproduction, $aN \to \pi{N}$, to include the impact of the Roper resonance $N^*(1440)$ together the previously studied $\Delta(1232)$ resonance. Our theoretical framework is chiral…

High Energy Physics - Phenomenology · Physics 2024-05-03 Cheng-Cheng Li , Tao-Ran Hu , Feng-Kun Guo , Ulf-G. Meißner

The relevance of the axial current for pion production processes off the nucleon with real or virtual photons is revisited. Employing the hypothesis of a partially conserved axial current (PCAC), it is shown that, when all of the relevant…

Nuclear Theory · Physics 2009-11-06 Helmut Haberzettl