Muon-pair and tau-pair production in two-photon collisions at LEP
The QED processes e+e− → e+e−μ+μ− and e+e− → e+e−τ+τ− are studied with the L3 detector at LEP using an untagged data sample collected at centre-of-mass energies 161 GeV ≤ √s 209 GeV. The τ -pairs are observed through the associated decay of one τ into eνν and the other into ππν. The cross sections a...
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| Autores principales: | , |
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| Formato: | Articulo |
| Lenguaje: | Inglés |
| Publicado: |
2004
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| Materias: | |
| Acceso en línea: | http://sedici.unlp.edu.ar/handle/10915/79918 |
| Aporte de: |
| Sumario: | The QED processes e+e− → e+e−μ+μ− and e+e− → e+e−τ+τ− are studied with the L3 detector at LEP using an untagged data sample collected at centre-of-mass energies 161 GeV ≤ √s 209 GeV. The τ -pairs are observed through the associated decay of one τ into eνν and the other into ππν. The cross sections are measured as a function of √s. For muon pairs, the cross section of the γ γ → μ+μ− process is also measured as a function of the two-photon centre-of-mass energy for 3 GeV ≤ W<sub>γγ</sub> 40 GeV. Good agreement is found between these measurements and the O(α<sup>4</sup>) QED expectations. In addition, limits on the anomalous magnetic and electric dipole moments of the τ lepton are extracted. |
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