Related papers: Pionic atoms probing pi-NN resonances
The consequences of a recently introduced irreducible pionic effect in low energy nucleon-deuteron scattering are analyzed. Differential cross-sections, nucleon (vector) and deuteron (vector and tensor) analyzing powers, and four different…
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…
Decays of baryon resonances in the second and the third resonance region into N pi0 pi0 are studied by photoproduction of two neutral pions off protons. Partial decay widths of N* and Delta* resonances decaying into Delta(1232) pi,…
At low energies the particle-hole (ph) part of the pionic susceptibility in isospin-symmetric nuclear matter is known to behave very differently from the susceptibility in finite nuclei due to the presence of an energy gap in the ph…
The decay of fireballs containing the disoriented chiral condensate (DCC) in A+A collisions has been analyzed. We found that the high phase-space density and probably the large final fireball volume are the favorable factors to extract a…
The coherent production of the nP states of the $\pi^+\pi^-$ atoms ($A_{2\pi}$) in relativistic nucleus-nucleus collisions is considered as a possible source of the $A_{2\pi}(nP)$ beam for the pionium Lamb-shift measurement. A general…
We assume that the nuclear potential for distances larger than 2.5 fm is given just by the exchanges of one and two pions and, for the latter, we adopt a model based on chiral symmetry and subthreshold pion-nucleon amplitudes, which…
Recent work on the connection between in-medium subthreshold $K^-N$ amplitudes and kaonic atom potentials is updated by using a next to leading order chirally motivated coupled channel separable interaction model that reproduces $\bar KN$…
Nucleon-antinucleon optical potential, which explains the experimental data for the processes $e^{+}e^{-}\rightarrow p\bar{p}$ and $e^{+}e^{-}\rightarrow\mbox{pions}$ near the threshold of $p\bar{p}$ pair production, is suggested. To obtain…
The photoproduction of pion off nucleon is investigated within a dynamical coupled-channels approach based on the Juelich pi-N model, which has been quite successful in the description of pi-N to pi-N scattering for center-of-mass energies…
Using the delta-shell representation we present a successful fit to neutron-proton and proton-proton scattering data below pion production threshold. A detailed overview of the theory necessary to calculate observables with this potential…
The production of d' dibaryons in heavy ion collisions due to the elementary process NN -> d' + pion is considered. The cross section NN -> d' + pion is estimated using the vacuum d' width = 0.5 MeV extracted from data on the double charge…
Replicated theoretical attempts of relativistic approaches to the pion self-energy in nuclear matter yield unphysical pion spectra. We demonstrate the crucial dependence of the calculated pion spectra on the correct relativistic accounting…
The first measurement is reported of the double-polarization observable G in photoproduction of neutral pions off protons, covering the photon energy range from 620 to 1120 MeV and the full solid angle. G describes the correlation between…
The pion-nucleon sigma term is a quantity involved in many important aspects of particle and nuclear physics. In this review I show its origin and how it is connected to important questions as the origin of mass of the ordinary matter,…
We study the in-medium properties of mesons $(\pi,\eta,\rho)$ and baryon resonances in cold nuclear matter within a coupled-channel analysis. The meson self energies are generated by particle-hole excitations. Thus multi-peak spectra are…
Based on measurements the branching ratios for the decay of the recently discovered dibaryon resonance $d^*(2380)$ into two-pion production channels and into the $np$ channel are evaluated. Possibilities for a decay into the isoscalar…
Polarization observables of the three charge states of the pion for the $\gamma d\to\pi NN$ reaction with polarized photon beam and/or oriented deuteron target are evaluated over the whole $\Delta$(1232)-resonance region adopting a…
The differential cross sections for $\pi^- p \to \gamma n$ and $\pi^+ n \to \gamma p$ are computed up to $O(p^3)$ in heavy baryon chiral perturbation theory (HBChPT). The expressions at $O(p)$ and $O(p^2)$ have no free parameters. There are…
Using results from the chiral perturbation theory for the s-wave interaction and the delta-resonance model for the p-wave interaction of pions with nucleons, we have evaluated the spectral functions of pions in asymmetric nuclear matter…