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arXiv · hep-ph/0110086

Two-photon mediated resonance production in e+e- collisions: cross sections and density matrices

F. A. Berends·R. van Gulik
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Abstract

Earlier described model amplitudes are used in this paper to evaluate both cross sections and density matrices for two-photon mediated resonance production in e^+e^- collisions. All 25 q\bar{q} low-lying ^1S_0, ^3P_J and ^1D_2 resonances can thus be treated. Two independent methods are described to obtain the resonance production density matrices and cross sections. These density matrices combined with a resonance decay density matrix give the detailed angular distributions of the resonance decay products. For two particular decays, χ_{c2},χ_{c1}\toγJ/ψthe details are given. Several numerical results are presented as well.

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F. A. Berends, R. van Gulik. 2001-10-05. Two-photon mediated resonance production in e+e- collisions: cross sections and density matrices. https://doi.org/10.1016/s0550-3213(01)00619-8

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