We report a new measurement of the B⁺ meson differential cross section d σ/d p_T at \sqrt{s}=1960 GeV. The data corresponds to an integrated luminosity of 739 pb^-1, collected with the upgraded CDF detector (CDF II) at the Fermilab Tevatron collider. B⁺ candidates are reconstructed through the decay B⁺ --> J/ψ K⁺, with J/ψ --> &mu⁺ &mu^-.

We measure the total cross section, in the central rapidity region |y| < 1 and for p_T(B⁺) > 6 GeV/c to be:

σ(p_T> 6GeV/c, |y|< 1) = 2.65 ± 0.12 (stat) ± 0.21 (syst) μb.

The values in the fourth and fifth columns are the cross sections before and after the correction for the Cabibbo suppressed mode  B⁺ --> J/ψ π⁺, respectively.

A more detailed summary of the results can be found here: ps pdf.

eps and gif versions of all figures:

• Figure 1: B^± mass (.eps) (.gif)
• Figure 2: B^± mass (6 < p_T < 9) (.eps) (.gif)
• Figure 3: B^± mass (9 < p_T < 12) (.eps) (.gif)
• Figure 4: B^± mass (12 < p_T < 15) (.eps) (.gif)
• Figure 5: B^± mass (15 < p_T < 25) (.eps) (.gif)
• Figure 6: B^± mass (25 < p_T) (.eps) (.gif)
• Figure 7: Muon reconstruction efficiency times acceptance measured with data (.eps) (.gif)
• Figure 8: Muon trigger efficiency measured with data (.eps) (.gif)
• Figure 9: Data versus MC comparison of Pt distributions (.eps) (.gif)
• Figure 10: Comparisons of differential cross section with theory (.eps) (.gif)