Cross section of the reaction e +e −→ π+π−π+π− below 1 GeV at CMD-2

• Published in: Physics letters. B Vol. 475; no. 1; pp. 190 - 197
• Main Authors: Akhmetshin, R.R., Anashkin, E.V., Arpagaus, M., Aulchenko, V.M., Banzarov, V.Sh, Barkov, L.M., Bashtovoy, N.S., Bondar, A.E., Bondarev, D.V., Bragin, A.V., Chernyak, D.V., Eidelman, S.I., Fedotovitch, G.V., Gabyshev, N.I., Grebeniuk, A.A., Grigoriev, D.N., Hughes, V.W., Karpov, S.V., Kazanin, V.F., Khazin, B.I., Koop, I.A., Korostelev, M.S., Krokovny, P.P., Kurdadze, L.M., Kuzmin, A.S., Logashenko, I.B., Lukin, P.A., Mikhailov, K.Yu, Milstein, A.I., Nesterenko, I.N., Okhapkin, V.S., Otboev, A.V., Polunin, A.A., Popov, A.S., Purlatz, T.A., Root, N.I., Ruban, A.A., Ryskulov, N.M., Shamov, A.G., Shatunov, Yu.M., Shwartz, B.A., Sibidanov, A.L., Sidorov, V.A., Skrinsky, A.N., Smakhtin, V.P., Snopkov, I.G., Solodov, E.P., Stepanov, P.Yu, Sukhanov, A.I., Thompson, J.A., Titov, V.M., Valishev, A.A., Yudin, Yu.V., Zverev, S.G.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 2000
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/S0370-2693(00)00043-5

Using 3.07 pb
−1 of data collected in the energy range 0.60–0.97 GeV by CMD-2, about 150 events of the process e
+e
−→
π
+
π
−
π
+
π
− have been selected. The energy dependence of the cross section agrees with the assumption of the
a
1(1260)
π intermediate state which is dominant above 1 GeV. For the first time
π
+
π
−
π
+
π
− events are observed at the
ρ meson energy. Under the assumption that all these events come from the
ρ meson decay, the value of the cross section at the
ρ meson peak corresponds to the following decay width:
Γ(ρ
0→π
+π
−π
+π
−)=(2.8±1.4±0.5)
keV
or to the branching ratio
B(ρ
0→π
+π
−π
+π
−)=(1.8±0.9±0.3)·10
−5.