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arXiv · hep-ex/0504015

Z-boson production with two unobserved, back-to-back, hard photons at LEP

L3 Collaboration
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Abstract

The double-radiative process e+e- -> Z gamma gamma -> q q~ gamma gamma, where the two hard photons escape detection at low polar angles into opposite directions, is studied in 0.62/fb of data collected with the L3 detector at LEP at centre-of-mass energies between 188.6GeV and 209.2GeV. The cross sections are measured and found to be consistent with the Standard Model expectations.

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L3 Collaboration. 2005-04-08. Z-boson production with two unobserved, back-to-back, hard photons at LEP. https://doi.org/10.1016/j.physletb.2005.03.039

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