Related papers: Interacting pion pairs in nuclear matter

The cross section for exclusive $\pi^+\pi^-$ and $\pi^0\pi^0$ meson pairs production in peripheral ultrarelativistic heavy-ion collisions is calculated at the energy available at the CERN Large Hadron Collider, i.e., $\sqrt{s_{NN}}=3.5$…

Positive pion and kaon production from Au+Au reactions have been measured as a function of beam energy over the range 2.0-10.7~AGeV. Both the kaon and the pion production cross-sections at mid-rapidity are observed to increase steadily with…

Within the framework of the relativistic Vlasov-Uehling-Uhlenbeck transport model based on the relativistic nonlinear NL$\rho$ interaction, we study pion in-medium effects on the $\pi^-/\pi^+$ ratio in Au+Au collisions at the energy of…

The cross section for exclusive production of $\pi^+ \pi^-$ and $\pi^0 \pi^0$ meson pairs in ultrarelativistic heavy ion collisions is calculated for LHC energy $\sqrt{s_{NN}} =$ 3.5 TeV taking into account photon-photon mechanism. We…

The cross section for prompt neutral and charged three pion production in pp interactions was measured at excess energies in the range 160 - 217 MeV. That comprises the first measurement of the pp->pp pi0pi0pi0 reaction and the comparison…

The reaction $p + d \rightarrow p + d + X$ was studied at 0.8-2.0 GeV proton beam energies with the ANKE magnetic spectrometer at the COSY synchrotron storage ring. The proton-deuteron pairs emerging with high momenta, 0.6-1.8 GeV/$c$, were…

The reaction pp->pppi0pi0 has been investigated at a beam energy of 1.4 GeV using the WASA-at-COSY facility. The total cross section is found to be (324 +- 21_systematic +- 58_normalization) mub. In order to to study the production…

We present a model of electron-positron pair production in pion-nucleon collisions in the exclusive reaction \pi N -> Ne^+e^-. The model is based on an effective field theory approach, incorporating 16 baryon resonances below 2 GeV.…

A first measurement of longitudinal as well as transverse spin correlation coefficients for the reaction $\vec{p}\vec{p}\to pn\pi^+$ was made using a polarized proton target and a polarized proton beam. We report kinematically complete…

A meson exchange model of the $\pi\pi$ interaction which fits free $\pi\pi$ scattering data is used to calculate the interactions of pions in nuclear matter as a function of nuclear density. Polarization of the nuclear medium by the pions…

The pion- and photon induced reactions for the final states $\gamma N$, $\pi N$, $2\pi N$, $\eta N$, and $\omega N$ are studied within a coupled-channel effective Lagrangian approach in the energy region from the pion threshold up to 2 GeV.…

We study the reaction $\pi^\pm p \to \pi^\pm \pi^+ n$ and $\pi^- p \to \pi^0 \pi^0 n$ in heavy-baryon chiral perturbation theory of chiral order three from threshold up to pion laboratory kinetic energies of 400 MeV. We find that the…

[Background] A quantitative understanding of neutrino interactions with nuclei is needed for precision era neutrino long baseline experiments (MINOS, NOvA, DUNE) which all use nuclear targets. Pion production is the dominant reaction…

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…

Charged pions from Ni + Ni reactions at 1.05, 1.45 and 1.93 AGeV are measured with the FOPI detector. The mean $\pi^{\pm}$ multiplicities per mean number of participants increase with beam energy, in accordance with earlier studies of the…

In order to establish links between p-wave pion production in nucleon-nucleon collisions and low energy three-nucleon scattering, an extensive programme of experiments on pion production is currently underway at COSY-ANKE. The final proton…

The reaction ${n} {p} \to {p} {p} \pi^{-}$ has been studied in a kinematically complete measurement with a large acceptance time-of-flight spectrometer for incident neutron energies between threshold and 570 MeV. The proton-proton invariant…

We present theoretical results for (gamma,pi0 pi0) and (gamma,pi+- pi0) production on nucleons and nuclei in the kinematical region where the scalar isoscalar pi pi amplitude is influenced by the sigma pole. The final state interaction of…

We study the possibility of measuring parity-violating pion-nucleon coupling h_{\pi NN}^{(1)} from \pi^+ electroproton production in the threshold region. We calculate the electron-helicity asymmetry in terms of h_{\pi NN}^{(1)} and the…

We examine the behavior of charged pions in neutron-rich matter using heavy-baryon chiral perturbation theory. This study is motivated by the prospect that pions, or pion-like excitations, may be relevant in neutron-rich matter encountered…