Related papers: Pionic Fluctuations of Constituent Quarks
We present the full decomposition of the momentum fraction carried by quarks and gluons in the pion and the kaon. We employ three gauge ensembles generated with $N_f=2+1+1$ Wilson twisted-mass clover-improved fermions at the physical quark…
We present the two-pion exchange contributions to the nucleon-nucleon interaction up to next-to-next-to-next-to leading order (N$^3$LO) in covariant baryon chiral perturbation theory. Both one-loop and two-loop diagrams are calculated with…
Electromagnetic form factors of the nucleon in the space-like region are investigated within the framework of a covariant and confining Nambu-Jona-Lasinio model. The bound state amplitude of the nucleon is obtained as the solution of a…
A calculation of the pion mass and decay constant at NNNLO in two-flavour chiral perturbation theory is presented. The results are cross-checked by using both the exponential and square root parameterizations of the Goldstone matrix field,…
Our extraction of the pion-nucleon coupling constant from \pi p elastic scattering data is outlined. A partial wave analysis (T_{\pi} < 2100 MeV) is performed simultaneously with a fixed-t dispersion relation analysis (T_{\pi} < 800 MeV).…
We investigate the effect of different relativistic spin couplings of constituent quarks on nucleon electroweak properties. Within each quark spin coupling scheme the correlations between static electroweak observables are found to be…
Relativistic exchange current corrections to neutrino--nucleus cross sections are presented assuming non--vanishing strange quark form factors for the constituent nucleons. For charged current processes the exchange current corrections can…
The electromagnetic nucleon form factors provide constraints on generalized quark distributions. Key results of the study presented here are a strong dependence of the average impact parameter of quarks on their longitudinal momentum…
A unified set of predictions for pion and kaon elastic electromagnetic and gravitational form factors is obtained using a symmetry-preserving truncation of each relevant quantum field equation. A key part of the study is a description of…
We investigate nucleon tensor form factors in the large-$N_{c}$ limit. In this picture, the nucleon emerges as a state of the $N_c$ valence quarks, which were bound by pion mean fields that were created by the presence of the valence quarks…
The anomaly (cusp) in the mass spectrum of two neutral pions from the three-pion decays of charged kaon has been observed in the NA48/2 experiment. Using the recently developed interpretation of this effect in terms of Chiral Perturbative…
We analyse the baryon magnetic moments in a model that relates them to the parton spins $\Delta u$, $\Delta d$, $\Delta s$, and includes a contribution from orbital angular momentum. The specific assumption is the existence of a 3-quark…
In the paper nucl-ex/0010009 by The Jefferson Lab F_pi Collaboration the new results for the charged pion electromagnetic form factor are presented. The approach given in our paper hep-ph/9811318, "On a possible estimation of the…
Calculation of ratio of the nucleon axial and vector coupling constants $G_A/G_V$ in the framework of the quasipotential quark model has been performed. It was shown that in this model $G_A/G_V$ is defined by the ratio of the corresponding…
We present results from calculations of conserved charge fluctuations in $(2+1)$-flavor QCD using light quark masses in the range $m_s/80 \leq m_l \leq m_s/27$, with the strange quark mass ($m_s$) kept fixed at its physical value. This…
The phase structure of baryonic matter is investigated with focus on the role of fluctuations beyond the mean-field approximation. The prototype test case studied is the chiral nucleon-meson model, with added comments on the chiral…
We explore the meson cloud contribution to nucleon electromagnetic form factors in dispersion relation approach. In our calculations, experimental data on transition amplitudes for pion-nucleon scatterings are taken directly as inputs, with…
The vector form factor of the decay $\pi^{+} \rightarrow \gamma + e^{+} + \nu_e$ is calculated by the method for the pseudovector pion-nucleon system. The non-perturbative term is taken into account by using the parameter for the…
The nucleon-pion-state contribution to QCD two- and three-point functions used in the calculation of the axial form factors of the nucleon are studied in chiral perturbation theory. For physically small quark masses the nucleon-pion states…
Different hadron transverse momentum spectra are calculated in a non-extensive statistical, quark-coalescence model. For the low-pT part a gluonic string contribution is conjectured, its length distribution and fractality are fitted to RHIC…