First observation of B̄s0→Ds±K and Measurement of the Ratio of Branching Fractions B(B̄s0→Ds±K)/ B(B̄s0→Ds+π-)
Physical Review Letters 103:19 (2009)
Abstract:
A combined mass and particle identification fit is used to make the first observation of the decay B̄s0→Ds±K□ and measure the branching fraction of B̄s0→Ds±K□ relative to B̄s0→Ds+π-. This analysis uses 1.2fb-1 integrated luminosity of pp̄ collisions at s=1.96TeV collected with the CDF II detector at the Fermilab Tevatron collider. We observe a B̄s0→Ds±K□ signal with a statistical significance of 8.1σ and measure B(B̄s0→ Ds±K□)/B(B̄s0→Ds+π-)=0.097±0.018(stat)±0. 009(syst). © 2009 The American Physical Society.Search for the Higgs boson produced in association with Z→ ℓ+ ℓ - Using the matrix element method at CDF II
Physical Review D - Particles, Fields, Gravitation and Cosmology 80:7 (2009)
Abstract:
We present a search for associated production of the standard model Higgs boson and a Z boson where the Z boson decays to two leptons and the Higgs decays to a pair of b quarks in pp̄ collisions at the Fermilab Tevatron. We use event probabilities based on standard model matrix elements to construct a likelihood function of the Higgs content of the data sample. In a CDF data sample corresponding to an integrated luminosity of 2.7fb-1 we see no evidence of a Higgs boson with a mass between 100GeV/c2 and 150GeV/c2. We set 95% confidence level upper limits on the cross section for ZH production as a function of the Higgs boson mass mH; the limit is 8.2 times the standard model prediction at mH=115GeV/c2. © 2009 The American Physical Society.Two Type Ic supernovae in low-metallicity, dwarf galaxies: diversity of explosions
(2009)