English
Related papers

Related papers: Common explanation of the behavior of some $e^+e^-…

200 papers

The excitation curve of e+e- annihilation into four charged pions in the rho(770) region is calculated using three existing models with rho mesons and pions in intermediate states supplemented by Feynman diagrams with the a_1(1260)pi…

High Energy Physics - Phenomenology · Physics 2008-11-26 Peter Lichard , Josef Juran

We analyze the origin of the structures observed in the reactions $e^+e^-\to 3(\pi^+\pi^-)$, $2(\pi^+\pi^-\pi^0)$, $\omega\pi^+\pi^-\pi^0$, and $e^+e^-\to 2(\pi^+\pi^-)\pi^0$ around the antiproton-proton ($\bar pp$) threshold. We calculate…

Nuclear Theory · Physics 2015-09-30 Johann Haidenbauer , Christoph Hanhart , Xian-Wei Kang , Ulf-G. Meißner

We report measurements of the observed cross sections for $e^+e^-\to\omega \pi^+\pi^-$, $\omega K^+K^-$, $\omega p\bar p$, $K^+K^-\rho^0\pi^0$, $K^+K^-\rho^+\pi^-+c.c.$, $K^{*0}K^-\pi^+\pi^0+c.c.$, $K^{*+}K^-\pi^+\pi^-+c.c.$,…

High Energy Physics - Experiment · Physics 2012-08-27 The BES Collaboration

Very recently, the {\it BABAR} Collaboration indicated that there exist an explicit enhancement structure near 2.2 GeV when focusing on the $e^+e^-\to\pi^+\pi^-$ process again, which inspires our interest in studying the production of…

High Energy Physics - Phenomenology · Physics 2020-09-01 Li-Ming Wang , Jun-Zhang Wang , Xiang Liu

The spectrum of light unflavored vector mesons above 2.4 GeV has not yet been firmly established experimentally. In this work, we demonstrate that the process $e^+e^- \to p\bar{p}\pi$ serves as a particularly promising channel as a probe…

High Energy Physics - Phenomenology · Physics 2025-09-10 Dan Guo , Jun-Zhang Wang , Qin-Song Zhou

We derive the amplitude for the process $e^+e^-\to \pi^0\pi^0$ at large invariant energy. The process goes through the two-photon exchange and its amplitude is expressed in terms of the convolution integral which depends on the shape of the…

High Energy Physics - Phenomenology · Physics 2009-11-23 N. A. Kivel , M. V. Polyakov

The cross section of reaction e^+e^-\to\pi^+\pi^-\pi^+\pi^- is calculated for energies 0.65\leq \sqrt{s}\leq1 GeV in the framework of the generalized hidden local symmetry model. The calculations are compared with the data of CMD-2 and…

High Energy Physics - Phenomenology · Physics 2009-02-19 N. N. Achasov , A. A. Kozhevnikov

The analysis of the vector isoscalar excitations in the energy range between 1 and 2 GeV of the $e^+e^-$ annihilation is presented for the final states $\pi^+\pi^-\pi^0$, $\omega\pi^+\pi^-$, $K^+K^-$, $K^0_SK^\pm\pi^\mp$ and…

High Energy Physics - Phenomenology · Physics 2008-11-26 N. N. Achasov , A. A. Kozhevnikov

The review of the SND results of the $e^+e^-\to\pi^+\pi^-\pi^0$ process study in the energy range $\sqrt[]{s}=0.42$ -- 1.38 GeV at VEPP-2M collider, based on about $2\times 10^6$ selected events, is presented. The total cross section,…

Based on the generalized hidden local symmetry as the chiral model of pseudoscalar, vector, and axial vector mesons, the excitation curve of the reaction e^+e^-\to\pi^+\pi^-\pi^+\pi^- is calculated for energies in the interval 0.65\leq…

High Energy Physics - Phenomenology · Physics 2009-01-06 N. N. Achasov , A. A. Kozhevnikov

The e+e- --> pi+pi-pi0pi0 reaction cross section as a function of the incident energy is calculated using a model that is an extension of our recently published model of the e+e- annihilation into four charged pions. The latter considered…

High Energy Physics - Phenomenology · Physics 2008-11-26 Josef Juran , Peter Lichard

We consider the $\pi^+\pi^-\pi_0\gamma$ final state in electron-positron annihilation at cms energies not far from the threshold. Both initial and final state radiations of the hard photon is considered but without interference between…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. Ahmedov , G. V. Fedotovich , E. A. Kuraev , Z. K. Silagadze

We present an analysis of the process $e^+e^-\to V^*\to\pi\pi\gamma$, where $V=\gamma$ or $V=Z$ boson, in the kinematical region where $\sqrt{s}$, the c.m. energy of the $e^+e^-$ pair, is large but much below the $Z$-pole. The subprocess…

High Energy Physics - Phenomenology · Physics 2014-11-18 Zhun Lu , Ivan Schmidt

The cross section of the process $e^+e^-\to \pi^+\pi^-\pi^0$ was measured in the Spherical Neutral Detector (SND) experiment at the VEPP-2M collider in the energy region $\sqrt[]{s}$ below 980 MeV. This measurement was based on about $1.2…

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.…

High Energy Physics - Phenomenology · Physics 2011-09-13 G. Ecker , R. Unterdorfer

Cross sections of the e+e- annihilation into one photon plus two vector mesons, such as J/psi rho, J/psi phi, and rho phi at the center of mass energy \sqrt{s}=10.58GeV are calculated. These shed light on the measurement of the e+e-…

High Energy Physics - Phenomenology · Physics 2008-11-26 K. Zhu , C. Z. Yuan , R. G. Ping

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…

High Energy Physics - Phenomenology · Physics 2023-12-07 G. I. Gakh , M. I. Konchatnij , N. P. Merenkov , E. Tomasi-Gustafsson

The \bar{nu}e^- --> pi^- pi^0 and nu e^+ --> pi^+ pi^0 reaction have a resonant structure whenever the energy of the s--channel equals the mass of a J^P=1^- vector meson. The resonant cross sections are of the order 10^{-38} cm^2 and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Emmanuel A. Paschos , Olga Lalakulich

The cross section for different processes induced by $e^+e^-$ annihilation, in the kinematical limit $\beta_{\mu}\approx\beta_{\pi}=(1-m_{\pi}^2/\epsilon^2)^{1/2}\sim 1$, is calculated taking into account first order corrections to the…

High Energy Physics - Phenomenology · Physics 2008-12-25 E. A. Kuraev , A. I. Ahmadov , S. N. Panov , E. Tomasi-Gustafsson
‹ Prev 1 2 3 10 Next ›