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Study of Multiphoton Final States and Tests of QED in e+e- collisions at \root(s) up to 209 GeV

L3 Collaboration
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Abstract

The process e+ e- -> n gamma with n>=2 is studied at centre-of-mass energies ranging from \root(s)=192 to 208 GeV. The data sample corresponds to a total integrated luminosity of 427 1/pb. The total and differential cross sections are found to be in agreement with the QED expectations. Using all the data collected with the L3 detector above the Z pole, limits on deviations from QED, excited electrons, contact interactions, extra space dimensions and excited spin-3/2 leptons are set.

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L3 Collaboration. 2002-02-11. Study of Multiphoton Final States and Tests of QED in e+e- collisions at \root(s) up to 209 GeV. https://doi.org/10.1016/s0370-2693(02)01339-4

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