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arXiv · hep-ex/0311028

Isolated tau leptons in events with large missing transverse momentum at HERA

ZEUS collaboration
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Abstract

A search for events containing isolated tau leptons and large missing transverse momentum, not originating from the tau decay, has been performed with the ZEUS detector at the electron-proton collider HERA, using 130 pb^-1 of integrated luminosity. A search was made for isolated tracks coming from hadronic tau decays. Observables based on the internal jet structure were exploited to discriminate between tau decays and quark- or gluon-induced jets. Three tau candidates were found, while 0.40 +0.12 -0.13 were expected from Standard Model processes, such as charged current deep inelastic scattering and single W-boson production. To search for heavy-particle decays, a more restrictive selection was applied to isolate tau leptons produced together with a hadronic final state with high transverse momentum. Two candidate events survive, while 0.20 +-0.05 events are expected from Standard Model processes.

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ZEUS collaboration. 2003-12-19. Isolated tau leptons in events with large missing transverse momentum at HERA. https://doi.org/10.1016/j.physletb.2003.12.054

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