Study of tau-pair production at HERA

A study of events containing two tau leptons with high transverse momentum has been performed with the ZEUS detector at HERA, using a data sample corresponding to an integrated luminosity of 0.33 fb-1. The tau candidates were identified from their decays into electrons, muons or hadronic jets. The number of tau-pair candidates has been compared with the prediction from the Standard Model, where the largest contribution is expected from Bethe-Heitler processes. The total visible cross section was extracted.Standard Model expectations agree well with the measured distributions, also at high invariant mass of the tau pair.

Note:

19 pages, 2 tables, 5 figures, minor corrections after submission to JHEP

Lepton-Nucleon Scattering
mass spectrum: (tau+ tau-)
transverse momentum: high
jet: transverse energy
DESY HERA Stor
Bethe-Heitler
ZEUS
electron p: inclusive reaction
photon photon: interaction
tau: pair production

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Figures(6)

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