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arXiv · hep-ex/9904024

a_1(1260) dominance in the process e+e- \to 4πat energies 1.05--1.38 GeV

CMD2 Collaboration
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Abstract

First results of the study of the process e+e- \to 4πby the CMD-2 collaboration at VEPP-2M are presented for the energy range 1.05--1.38 GeV. Using an integrated luminosity of 5.8 pb^{-1}, energy dependence of the processes e+e- \to π^+π^- 2π^0 and e+e- \to 2π^+ 2π^- has been measured. Analysis of the differential distributions demonstrates the dominance of the a_1πand ωπintermediate states. Upper limits for the contributions of other alternative mechanisms are also placed.

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CMD2 Collaboration. 1999-04-23. a_1(1260) dominance in the process e+e- \to 4πat energies 1.05--1.38 GeV. https://doi.org/10.1016/s0370-2693(99)01080-1

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