First observation of the decay Bs0→Ds-Ds+ and measurement of its branching ratio
Physical Review Letters 100:2 (2008)
Abstract:
We report the observation of the exclusive decay Bs0→Ds-Ds+ at the 7.5 standard deviation level using 355pb-1 of data collected by the CDF II detector in pp̄ collisions at s=1.96TeV at the Fermilab Tevatron. We measure the relative branching ratio B(Bs0→Ds-Ds+)/B(B0→D-Ds+)=1.44-0.44+0.48. Using the world average value for B(B0→D-Ds+), we find B(Bs0→Ds-Ds+)= (9.4-4.2+4.4)×10-3. This provides a lower bound ΔΓsCP/Γs 2B(Bs0→Ds-Ds+)>1.2×10-2 at 95% C.L. © 2008 The American Physical Society.Erratum to: "Measurement of the isolated photon cross section in p over(p, ̄) collisions at sqrt(s) = 1.96 TeV" [Phys. Lett. B 639 (2006) 151] (DOI:10.1016/j.physletb.2006.04.048)
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 658:5 (2008) 285-289
Measurement of the ratios of the Z / γ* + ≥ n jet production cross sections to the total inclusive Z / γ* cross section in p over(p, -) collisions at sqrt(s) = 1.96 TeV
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 658:4 (2008) 112-119
Abstract:
We present a study of events with Z bosons and associated jets produced at the Fermilab Tevatron collider in p over(p, ̄) collisions at a center of mass energy of 1.96 TeV. The data sample consists of nearly 14 000 Z / γ* → e+ e- candidates corresponding to an integrated luminosity of 0.4 fb-1 collected with the DØ detector. Ratios of the Z / γ* + ≥ n jet cross sections to the total inclusive Z / γ* cross section have been measured for n = 1 - 4 jets, and found to be in good agreement with a next-to-leading order QCD calculation and with a tree-level QCD prediction with parton shower simulation and hadronization.Forward π± production in p-O2 and p-N2 interactions at 12 GeV/c
Astroparticle Physics 30:3 (2008) 124-132
Abstract:
Measurements of double-differential charged pion production cross-sections in interactions of 12 GeV/c protons on O2 and N2 thin targets are presented in the kinematic range 0.5 GeV/c ≤ pπ < 8 GeV/c and 50 mrad ≤ θπ < 250 mrad (in the laboratory frame) and are compared with p-C results. For p-N2 (p-O2) interactions the analysis is performed using 38576 (7522) reconstructed secondary pions. The analysis uses the beam instrumentation and the forward spectrometer of the HARP experiment at CERN PS. The measured cross-sections have a direct impact on the precise calculation of atmospheric neutrino fluxes and on the improved reliability of extensive air shower simulations by reducing the uncertainties of hadronic interaction models in the low energy range. In particular, the present results allow the common hypothesis that p-C data can be used to predict the p-N2 and p-O2 pion production cross-sections to be tested. © 2008 Elsevier B.V. All rights reserved.Large-angle production of charged pions by 3 GeV/c-12 GeV/c protons on carbon, copper and tin targets
European Physical Journal C 53:2 (2008) 177-204