Isolated tau leptons in events with large missing transverse momentum at HERA
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 583:1-2 (2004) 41-58
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 -0.13+0.12 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. © 2004 Published by Elsevier B.V.Observation of KS 0KS 0 resonances in deep inelastic scattering at HERA
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 578:1-2 (2004) 33-44
Abstract:
Inclusive Ks0Ks0 production in deep inelastic ep scattering at HERA has been studied with the ZEUS detector using an integrated luminosity of 120 pb-1. Two states are observed at masses of 1537-8-9 MeV and 1726 ± 7 MeV, as well as an enhancement around 1300 MeV. The state at 1537 MeV is consistent with the well established f′2(1525). The state at 1726 MeV may be the glueball candidate f0(1710). However, it's width of 38 -14-20 MeV is narrower than 125 ± 10 MeV observed by previous experiments for the f0(1710). © 2003 Elsevier B.V. All rights reserved.Review of jet results from HERA
Acta Physica Polonica B 35:1 (2004) 377-386
Abstract:
Some of the most recent results on jet production at HERA are reviewed. The measurements are confronted with predictions from next-to-leading order Quantum Chromodynamics. In regions where uncertainties are small, the strong coupling, αs, has been extracted. Other topics of current interest are also highlighted.Bottom photoproduction measured using decays into muons in dijet events in ep collisions at √s=318 GeV -: art. no. 012008
PHYSICAL REVIEW D 70:1 (2004) ARTN 012008
Exclusive electroproduction of J/ψ mesons at HERA
NUCLEAR PHYSICS B 695:1-2 (2004) 3-37