Measurement of exclusive D meson decays to η and η′ final states and SU(3) amplitude analysis
Physical Review D - Particles, Fields, Gravitation and Cosmology 77:9 (2008)
Abstract:
Using 281pb-1 of data collected with the CLEO-c detector, we present new measurements of Cabibbo-suppressed decays of D0 and D+ mesons to η and η′ final states. We make first observations of D0→η′ π0, ηη, ηη′, and ηπ+π-, and find evidence for D+→ηπ+π0, D+→η′π+π0, and D0→η′π+π-. We also report on improved measurements of D0→ηπ0, D+→ηπ+, and D+→η′π+. Using the measured two-body Cabibbo-suppressed decays, we extract amplitudes for specific flavor topologies and compare them to those from Cabibbo-favored decays. © 2008 The American Physical Society.Absolute branching fractions of Cabibbo-suppressed D→KK̄ decays
Physical Review D - Particles, Fields, Gravitation and Cosmology 77:9 (2008)
Abstract:
Using 281pb-1 of data collected with the CLEO-c detector at the ψ(3770) resonance, we have studied Cabibbo-suppressed decays of D mesons to final states with two kaons. We present results for the absolute branching fractions of the modes D0→K+K-, D0→KS0KS0, and D+→K+KS0. We measure B(D0→K+K-)=(4.08±0.08±0.09)×10-3, B(D0→KS0KS0)=(1. 46±0.32±0.09)×10-4, and B(D+→K+KS0)=(3.14±0. 09±0.08)×10-3. We also determine the ratio B(D0→K+K-)/ B(D0→π+π-)=2.89±0.05±0.06. For each measurement, the first uncertainty is statistical and the second uncertainty is systematic. © 2008 The American Physical Society.Measurement of the tt̄ production cross section in pp̄ collisions at s=1.96TeV
Physical Review Letters 100:19 (2008)
Abstract:
We measure the tt̄ production cross section in pp̄ collisions at s=1.96TeV in the lepton+jets channel. Two complementary methods discriminate between signal and background: b tagging and a kinematic likelihood discriminant. Based on 0.9fb-1 of data collected by the D0 detector at the Fermilab Tevatron Collider, we measure σtt̄=7.62±0.85pb, assuming the current world average mt=172.6GeV. We compare our cross section measurement with theory predictions to determine a value for the top-quark mass of 170±7GeV. © 2008 The American Physical Society.First observation of the decay Ds+→pn̄
Physical Review Letters 100:18 (2008)
Abstract:
Using e+e-→Ds*-Ds+ data collected near the peak Ds production energy, Ecm=4170MeV, with the CLEO-c detector, we present the first observation of the decay Ds+→pn̄. We measure a branching fraction B(Ds+→pn̄)=(1.30±0.36-0.16+0.12)×10-3. This is the first observation of a charmed meson decaying into a baryon-antibaryon final state. © 2008 The American Physical Society.Absolute measurement of hadronic branching fractions of the Ds+ meson
Physical Review Letters 100:16 (2008)