Related papers: Parity violating pion electroproduction off the nu…
Because the nucleon may be excited and transformed into a virtual $\Delta$ resonance easily, we consider the decuplet contribution to the parity-violating (PV) nucleon-nucleon interaction in the chiral effective field theory. The effective…
We consider a pionless effective theory with dibaryon fields for the description of the weak process involving two nucleons. We construct leading order Lagrangians that contain nucleon-dibaryon weak coupling constants. We calculate the…
An intrinsic parity violating hadronic tau lepton decay is investigated. $\tau \to \pi \pi \eta \nu$ is the process in which the dominant contribution to the amplitude is due to the intrinsic parity violation. To predict the hadronic…
We investigate the pion photoproduction in the \Delta(1232) region in the framework of an effective Lagrangian including pions, nulceon and \Delta(1232). We work to third order in a small scale expansion with both $m_{\pi}$ and…
The longitudinal asymmetry due to $Z^0$ exchange is calculated in quasi-elastic electron-deuteron scattering at momentum transfers $|Q^2| \simeq 0.1$ GeV$^2$ relevant for the SAMPLE experiment. The deuteron and $pn$ scattering-state wave…
We analyze parity-violating nucleon-nucleon scattering at energies E<m_\pi^2/M using the effective field theory appropriate for this regime. The minimal Lagrangian for short-range parity-violating NN interactions is written in an operator…
We investigate the parity-violating nucleon-nucleon potential as obtained in chiral effective field theory. By using resonance saturation we compare the chiral potential to the more traditional one-meson exchange potential. In particular,…
We calculate in chiral perturbation theory the parity-violating two-pion exchange nucleon-nucleon potentials at leading one-loop order. At a distance of $r= m_\pi^{-1} \simeq 1.4 $fm they amount to about $\pm 16%$ of the parity-violating…
Parity violation in elastic electron-nucleon scattering is studied with the basic goal of improving the understanding of electroweak hadronic structure with special emphasis on the strangeness content in the nucleon. Models for the…
Incoherent pion photoproduction on the deuteron in the $\Delta$(1232)-resonance region is investigated with special emphasis on polarization observables. For the elementary pion photoproduction operator an effective Lagrangian model which…
We analyze the degree to which parity-violating (PV) electroexcitation of the $\Delta(1232)$ resonance may be used to extract the weak neutral axial vector transition form factors. We find that the axial vector electroweak radiative…
We show that the parity of the $h Z\gamma$ vertex can be probed by interference between the gluon fusion Higgs production, $gg \to h \to \gamma Z \to \gamma \ell^+\ell^-$, and the background, $gg \to \gamma Z \to \gamma \ell^+\ell^-$,…
Unambiguous isospin violation in the strong interaction sector is a key issue in low energy hadronic physics, both experimentally and theoretically. Bernstein has employed the Fermi-Watson theorem to demonstrate that pion photoproduction is…
Chiral effective field theory predicts a specific charge symmetry violating amplitude for pion production. This term is shown to provide the dominant contribution to the forward-backward asymmetry in the angular distribution for the…
We apply the formalism of Chiral Perturbation Theory out of thermal equilibrium to describe explosive production of pions via the parametric resonance mechanism. To lowest order the lagrangian is that of the Nonlinear Sigma Model where the…
We study the parity-violating effects in $nd\rightarrow$ $^3H\gamma$ process using pionless effective field theory (EFT($//!/!/!/pi$)) at thermal energy. For the weak $NN$ interaction the parity-violating Lagrangian contains five…
A model calculation for pion production in nucleon-nucleon collisions is presented. Direct production, pion rescattering and contributions from pair diagrams are taken into account. The amplitudes for the elementary processes are based on…
Electroproduction of pions on the nucleon near the threshold is analyzed within the framework of baryon chiral perturbation theory. We give a thorough discussion of the low--energy theorems related to charged and neutral…
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…
With an effective Lagrangian approach, we analyze several NN \to NN\pi\pi channels by including various resonances with mass up to 1.72 GeV. For the channels with the pion pair of isospin zero, we confirm the dominance of N*(1440)\to…