Optimized search for single-top-quark production at the Fermilab Tevatron
Physical Review D - Particles, Fields, Gravitation and Cosmology 69:5 (2004)
Abstract:
We use a neural-network technique to search for standard model single-top-quark production in the [Formula Presented] dataset accumulated by the Collider Detector at Fermilab detector during the 1992–1995 collider run (“run I”). Using a sample of 64 [Formula Presented] 2, 3 jets events, we set a 95% confidence level upper limit of 24 pb on the W-gluon and [Formula Presented] combined single-top cross section. © 2004 The American Physical Society.Search for Bs->mu+mu- and Bd->mu+mu- Decays in ppbar Collisions at sqrt(s)=1.96 TeV
ArXiv hep-ex/0403032 (2004)
Bose-Einstein correlations in one and two dimensions in deep inelastic scattering
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 583:3-4 (2004) 231-246
Abstract:
Bose-Einstein correlations in one and two dimensions have been studied in deep inelastic ep scattering events measured with the ZEUS detector at HERA using an integrated luminosity of 121 pb-1. The correlations are independent of the virtuality of the exchanged photon, Q2, in the range 0.1 < Q2 < 8000 GeV2. There is no significant difference between the correlations in the current and target regions of the Breit frame for Q2 > 100 GeV2. The two-dimensional shape of the particle-production source was investigated, and a significant difference between the transverse and the longitudinal dimensions of the source is observed. This difference also shows no Q2 dependence. The results demonstrate that Bose-Einstein interference, and hence the size of the particle-production source, is insensitive to the hard subprocess. © 2004 Published by Elsevier B.V.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.Optimized search for single-top-quark production at the Fermilab Tevatron
Physical Review D American Physical Society (APS) 69:5 (2004) 052003