Wide-field optical imaging on ELAIS N1, ELAIS N2, First Look Survey and Lockman Hole: observations and source catalogues
\mnras 416 (2011) 927-940-927-940
Evidence for tt̄γ production and measurement of σtt̄γ /σtt̄
Physical Review D - Particles, Fields, Gravitation and Cosmology 84:3 (2011)
Abstract:
Using data corresponding to 6.0fb-1 of pp̄ collisions at √s=1.96TeV collected by the CDF II detector, we present a cross section measurement of top-quark pair production with an additional radiated photon in the central region with 10 GeV or more of transverse energy tt̄γ. The events are selected by looking for a lepton (ℓ or μ), a photon (γ), significant transverse momentum imbalance (ET), large total transverse energy, and three or more jets, with at least one identified as containing a b quark (b). Using an event selection optimized for the tt̄γ candidate sample, we also measure the cross section of tt̄ (σtt̄). We measure the tt̄γ cross section (σtt̄γ) to be 0.18±0.08pb, and the ratio of σtt̄γ to σtt̄ to be 0.024±0.009. We observe a probability of 0.0015 (3.0 standard deviations) of the background (non-tt̄γ events alone producing 30 events or more. © 2011 American Physical Society.Observation of the Ξb0 baryon
Physical Review Letters 107:10 (2011)
Abstract:
The observation of the bottom, strange baryon Ξb0 through the decay chain Ξb0→Ξc+π-, where Ξc+→Ξ -π+π+, Ξ -→Λπ-, and Λ→pπ-, is reported by using data corresponding to an integrated luminosity of 4.2fb-1 from pp̄ collisions at √s=1.96TeV recorded with the Collider Detector at Fermilab. A signal of 25.3-5.4+5.6 candidates is observed whose probability of arising from a background fluctuation is 3.6×10-12, corresponding to 6.8 Gaussian standard deviations. The Ξb0 mass is measured to be 5787.8±5.0(stat)±1.3(syst)MeV/ c2. In addition, the Ξb- baryon is observed through the process Ξb-→Ξc0π-, where Ξc0→Ξ -π+, Ξ-→Λπ-, and Λ→pπ-. © 2011 American Physical Society.Radio observations of Circinus X-1 over a complete orbit at an historically faint epoch
(2011)
Search for three-jet resonances in pp collisions at √s=7TeV
Physical Review Letters 107:10 (2011)