相关论文: Coherent Pion Pairs from Heavy-Ion Collisions
Intense spatio-spectral twin beams generated in the regime with pump depletion are analyzed applying a suggested quantum model that treats the signal, idler and pump fields in the same way. The model assumes the signal and idler fields in…
A cascade model has been developed to study pion induced multichannel reactions (quasielastic, SCX, DCX, absorption and pion production) at pion energies above 0.5 GeV. Special attention has been paid to pion double charge exchange. Pion…
Recently it has been shown that the observed antiproton yield in heavy-ion collisions at CERN-SpS energies can be understood by multi-pionic interactions which enforce local chemical equilibrium of the antiprotons with the nucleons and…
Recently, significant enhancements of $e^{+} e^{-}$ pair production at very low transverse momentum ($p_{T} < 0.15$ GeV/c) were observed by the STAR collaboration in peripheral hadronic A+A collisions. This excesses can not be described by…
We derive the long-range components of the nucleon-nucleon (NN) two-pion-exchange potential with an intermediate Roper resonance. Leading-order interactions in heavy-baryon chiral perturbation theory are considered. NN phase shifts with…
The main part of coherent pion production by neutrinos on nuclei is essentially determined by PCAC, provided that the leptonic momentum transferred square Q^2 remains sufficiently small. We give the formulas for the charged and neutral…
The effects of two kinds of coherent lengths, the wave packet length of the emitter and the radius of the coherent source, on pion spectrum distribution are studied. It is shown that both coherent lengths can cause abundant pions at low…
A general derivation of the multi-pion correlation function for completely chaotic source is given. Its effects on the pion multiplicity distribution, two-pion interferometry are studied. A generalized multi-pion correlation function for a…
Heavy nuclei at collider energies are a source of high energy Weizsaecker-Williams photons. This photon flux may be utilized to study high energy photon-nucleus interactions. Here we concentrate on the coherent diffractive production of…
Various pion and photon production mechanisms in high-energy nuclear collisions at RHIC and LHC are discussed. Comparison with RHIC data is done whenever possible. The prospect of using electromagnetic probes to characterize quark-gluon…
We study one pion production in both charged and neutral current neutrino nucleus scattering for neutrino energies below 2 GeV. We use a theoretical model for one pion production at the nucleon level that we correct for medium effects. The…
Within an isospin- and momentum-dependent transport model, we investigate the necessity of selfconsistent calculations for the electromagnetic field in probing the nuclear symmetry energy using pion observables in heavy-ion collisions at…
We report on double-differential inclusive cross-sections of the production of secondary protons, charged pions, and deuterons, in the interactions with a 5% nuclear interaction length thick stationary tin target, of proton and pion beams…
Neutrino-induced pion production on nuclear targets is the major inelastic channel in all present-day neutrino-oscillation experiments. It has to be understood quantitatively in order to be able to reconstruct the neutrino-energy at…
A large data set of charged-pion electroproduction from both hydrogen and deuterium targets has been obtained spanning the low-energy residual-mass region. These data conclusively show the onset of the quark-hadron duality phenomenon, as…
A self-consistent symmetry arises when the nucleon angular momentum j and the isospin t are coupled to a grand spin G. Closed G shells become sources of a classical pion field with a hedgehog shape. Although the amplitude of the pion field,…
We present a study of two-particle correlation functions involving photons and neutral pions in proton-proton and lead-lead collisions at the LHC energy. The aim is to use these correlation functions to quantify the effects of the medium on…
Ultra-peripheral collisions (UPCs) of ions allow us to study photonuclear and two-photon interactions at energies above those available at fixed target accelerators. For heavy ions, the couplings are large enough so that multi-photon…
Within a dynamical coupled-channels model which has already been fixed from analyzing the data of the pi N -> pi N and gamma N -> pi N reactions, we present the predicted double pion photoproduction cross sections up to the second resonance…
We study the effects of channel coupling in the excitation dynamics of giant resonances in relativistic heavy ions collisions. For this purpose, we use a semiclassical approximation to the Coupled-Channels problem and separate the Coulomb…