Study of dynamics of the process $$e^+e^-\rightarrow \pi ^+\pi ^-\pi ^0$$ in the energy range 1.15–2.00 GeV
/ Authors
M. Achasov, M. Achasov, A. Barnyakov, A. Barnyakov, A. A. Baykov, A. A. Baykov, K. Beloborodov, K. Beloborodov, A. Berdyugin, A. Berdyugin
and 52 more authors
D. Berkaev, D. Berkaev, A. Bogdanchikov, A. Botov, T. Dimova, T. Dimova, V. Druzhinin, V. Druzhinin, V. Golubev, A. Kirpotin, L. Kardapoltsev, L. Kardapoltsev, A. Kasaev, A. Kharlamov, A. Kharlamov, I. Koop, I. Koop, A. Korol, A. Korol, D. Kovrizhin, A. Kupich, K. Martin, N. Melnikova, N. Muchnoy, N. Muchnoy, A. Obrazovsky, E. Pakhtusova, K. Pugachev, K. Pugachev, D. Rabusov, Y. Rogovsky, Y. Rogovsky, Y. Savchenko, Y. Savchenko, A. Senchenko, A. Senchenko, S. Serednyakov, S. Serednyakov, D. Shatilov, Y. Shatunov, Y. Shatunov, D. Shtol, D. Shwartz, D. Shwartz, Z. Silagadze, Z. Silagadze, I. Surin, M. Timoshenko, Y. Usov, V. Zhabin, V. Zhulanov, V. Zhulanov
/ Abstract
The dynamics of the process $$ e^+e^- \rightarrow \pi ^+\pi ^-\pi ^0 $$ is studied in the energy region from 1.15 to 2.00 GeV using data accumulated with the SND detector at the VEPP-2000 $$e^+e^-$$ collider. The Dalitz plot distribution and $$\pi ^+\pi ^-$$ mass spectrum are analyzed in a model including the intermediate states $$\rho (770)\pi $$ , $$\rho (1450)\pi $$ , and $$\omega \pi ^0$$ . As a result, the energy dependences of the $$\rho (770)\pi $$ and $$\rho (1450)\pi $$ cross sections and the relative phases between the $$\rho (770)\pi $$ amplitude and the $$\rho (1450)\pi $$ and $$\omega \pi ^0$$ amplitudes are obtained. The $$\rho (1450)\pi $$ cross section has a peak in the energy region of the $$\omega (1650)$$ resonance (1.55–1.75 GeV). In this energy range the contributions of the $$\rho (770)\pi $$ and $$\rho (1450)\pi $$ states are of the same order of magnitude. No resonance structure near 1.65 GeV is observed in the $$\rho (770)\pi $$ cross section. We conclude that the intermediate state $$\rho (1450)\pi $$ gives a significant contribution to the decay of $$\omega (1650)\rightarrow \pi ^+\pi ^-\pi ^0$$ , whereas the $$\rho (770)\pi $$ mechanism dominates in the decay $$\omega (1420)\rightarrow \pi ^+\pi ^-\pi ^0$$ .
Journal: European Physical Journal C