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Measurement of Exclusive ρ^+ρ^- Production in High-Q^2 Two-Photon Collisions at LEP

L3 Collaboration
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Abstract

Exclusive rho^+ rho^- production in two-photon collisions involving a single highly-virtual photon is studied with data collected at LEP at centre-of-mass energies 89 GeV < \sqrt{s} < 209 GeV with a total integrated luminosity of 854.7 pb^-1. The cross section of the process gamma gamma^* -> rho^+ rho^- is determined as a function of the photon virtuality, Q^2, and the two-photon centre-of-mass energy, W_gg, in the kinematic region: 1.2 GeV^2 < Q^2 < 30 GeV^2 and 1.1 GeV < W_gg < 3 GeV. The ρ^+ρ^- production cross section is found to be of the same magnitude as the cross section of the process gamma gamma^* -> rho^0 rho^0, measured in the same kinematic region by L3, and to have similar W_gg and Q^2 dependences.

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L3 Collaboration. 2004-07-12. Measurement of Exclusive ρ^+ρ^- Production in High-Q^2 Two-Photon Collisions at LEP. https://doi.org/10.1016/j.physletb.2004.07.013

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