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Title: Electron-positron annihilation into four charged pions and the a{sub 1}{rho}{pi} Lagrangian

Journal Article · · Physical Review. D, Particles Fields
 [1];  [1]
  1. Institute of Physics, Silesian University in Opava, Bezrucovo nam. 13, 746 01 Opava (Czech Republic)

The excitation curve of e{sup +}e{sup -} 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{sub 1}(1260){pi} intermediate states. A two-term phenomenological Lagrangian of the a{sub 1}{rho}{pi} interaction is used. The mixing angle is determined by fitting the e{sup +}e{sup -}{yields}{pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} cross section data of the Novosibirsk CMD-2 Collaboration and also its combination with the low-energy part of the BABAR Collaboration data. It is shown that the inclusion of the a{sub 1}{pi} intermediate states succeeds in obtaining a good agreement with the data on both cross section and the {rho}{sup 0}{yields}{pi}{sup +}{pi}{sup -}{pi}{sup +}{pi}{sup -} decay width. When moving to energies above 1 GeV, the {rho}(1450) and {rho}(1700) resonances are taken into account to get excellent agreement with the BABAR data over the full energy range up to 4.5 GeV.

OSTI ID:
21032580
Journal Information:
Physical Review. D, Particles Fields, Vol. 76, Issue 9; Other Information: DOI: 10.1103/PhysRevD.76.094030; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
Country of Publication:
United States
Language:
English