相关论文: Pion Correlations and Resonance Effects in ppbar A…
We report on a detailed investigation of four-body $p p \to p p \pi^+ \pi^-$ and $p \bar{p} \to p \bar{p} \pi^+ \pi^-$) reactions which constitute an irreducible background to three-body processes $p p \to p p M$, where $M$ is a broad…
The pion multiplicity distribution is widely believed to reflect the statistical aspects of $\bar{p}p$ annihilation at rest. We try to reproduce it in a grand canonical picture with explicit conservation of electric charge, isospin, total…
We evaluate differential distributions for the four-body $p p \to p p \pi^+ \pi^-$ reaction which constitutes a irreducible background to three-body processes $p p \to p p M$, where $M$ are a broad resonances in the $\pi^+ \pi^-$ channel,…
The behavior of the pion dispersion relation in a pion medium is strongly modified by the introduction of a finite chemical potential associated to the finite pion number density. Such behavior is particularly important during the hadronic…
The methods allowing to extract the coherent component of pion emission conditioned by the formation of a quasi-classical pion source in heavy ion collisions are suggested. They exploit a nontrivial modification of the quantum statistical…
The general analysis of the differential cross section and various polarization observables is performed for the process $e^+ + e^- \to N + \bar N +\pi^0 $ assuming that the annihilation occurs through the exchange of one virtual photon.…
The nonresonant mechanism in the reactions $e^+\,e^-\to \pi^-\,p\,\bar{n}$ and $e^+\,e^-\to \pi^+\,n\,\bar{p}$ is investigated in frame of the one-photon exchange approximation. The description of the hadronic phase space and the invariant…
The effects of the freeze-out hypersurface and resonance decays on the pion correlation functions in relativistic heavy-ion collisions are studied with help of the hydro-inspired models with single freeze-out. The heavy-ion Monte-Carlo…
Ten resonances were found in the mass spectrum of pi+pi- -system from the reaction np->nppi+pi- in np-interactions at Pn=5.20 GeV/c in the 1-m HBC of LHE JINR by using the criterion cos(teta)[c.m.c.] p>0. Such effects were not found in…
The novel point of this analysis is a direct use of reggeon exchange technique for the description of the reactions $\pi N\to two mesons + N$ at large energies of the initial pion. This approach allows us to describe simultaneously…
We present some results on the analysis of three pion resonances. The analyses are motivated by the recent release of the largest data set on diffractively produced three pions by the COMPASS collaboration. We construct reaction amplitudes…
We present preliminary results of searches for exclusive $B^0$ decays to $\pi^+\pi^-\pi^0$ among 22.7 million $b\bar{b}$ pairs collected by the BABAR experiment from electron-positron collisions near the $\Upsilon(4S)$ resonance. We measure…
Within the framework of a thermal model with its parameters fitted to the results from an isospin-dependent Boltzmann-Uehling-Uhlenbeck (IBUU) transport model, we study the pion in-medium effect on the charged-pion ratio in heavy-ion…
We consider pion interactions in an effective field theory of the narrow resonance X(3872), assuming it is a weakly bound molecule of the charm mesons D^{0} \bar D^{*0} and D^{*0} \bar D^{0}. Since the hyperfine splitting of the D^{0} and…
We review our recent study of the pion mass dependence of the rho and sigma resonances, generated from one-loop SU(2) Chiral Perturbation Theory (ChPT) with the Inverse Amplitude Method (IAM). In order to properly account for the Adler zero…
We calculate the processes e+ e- -> 4 pions and tau -> nu_tau + 4 pions to O(p^4) in the low-energy expansion of the standard model. The chiral amplitudes of O(p^4) can be extended via resonance exchange to energies around 1 GeV.…
We study the pp \to pp\pi^0 reaction near threshold based on heavy-baryon chiral perturbation theory. We show that the two-pion-exchange diagrams give much larger contribution than the one-pion-exchange diagram which is of lower chiral…
In frame of a phenomenological approach based on Compton-like Feynman amplitudes, we study multi-pion production in antiproton nucleon collisions. The main interest of this reaction is related to the possibility to study the properties of…
We investigate two- and three-particle intensity correlation functions of pions in relativistic heavy ion collisions for different colliding energies. Based on three models of particle production, we analyze the degree to which the pion…
We review our recent study of the pion mass dependence of the rho and sigma resonances generated from one-loop SU(2) Chiral Perturbation Theory (ChPT) with the Inverse Amplitude Method (IAM) which was modified to properly account for the…