** H**_{b} Cross Section Measured Using H_{b} → &mu D^{0}, D^{0} → &pi K
This web page summarizes the results for the measurement
of the H_{b} cross section using the decays H_{b} → &mu D^{0}, D^{0} → &pi K and H_{b} → &mu D^{*+}, D^{*+} →D^{0} &pi^{+}_{s}, D^{0} → &pi K based upon 83 pb^{-1} of
data. Here, H_{b} is an admixture of b hadrons.

The results have been approved as of October 25, 2006.

For H_{b} with p_{T} > 9.0 GeV/c and |y| < 0.6, we measure:

##
- &sigma(pp→H
_{b}) × BR(H_{b}→&mu^{-} D^{0} X) × BR(D^{0}→&pi^{+}K^{-} ) = 3.53 nb ± 0.20 nb (stat.) +0.34 -0.36 (syst.) nb
- &sigma(pp→H
_{b}) × BR(H_{b}→&mu^{-} D^{*+} X) × BR(D^{*+}→D^{0}&pi^{+} )× BR(D^{0}→&pi^{+}K^{-} ) = 1.04 nb ± 0.13 nb (stat.) +0.12 -0.14 (syst.) nb

We correct for the branching ratios taken from PDG 2004 2005 partial update for edition 2006. This gives:
##
- &sigma(pp→H
_{b}) = 1.34 μb ± 0.08 μb (stat.) +0.13 -0.14 (syst.) μb ± 0.07 μb (BR) (from D^{0})
- &sigma(pp→H
_{b}) = 1.47 μb ± 0.18 μb (stat.) +0.17 -0.19 (syst.) μb ± 0.11 μb (BR) (from D^{*+})

Recent fixed order next leading log (FONLL) calculations predict [1]:

&sigma(pp→H_{b}) = 1.39 μb +0.49 -0.34 μb

for H_{b} with with p_{T} > 9.0 GeV/c and |y| < 0.6.

[1] M. Cacciari, S. Frixione, M.L. Mangano, P. Nason, G. Ridolfi, JHEP 0407:033 (2004),
hep-ph/0312132

Below are the eps versions of all figures meant for downloads.

- Figure 1: &pi
^{+}K^{-} mass. The black histogram has q_{&mu}≠q_{&pi} and the red histogram has q_{&mu}=q_{&pi} (.eps)
- Figure 2: &pi
^{+}_{soft}&pi^{+}K^{-} mass - &pi^{+}K^{-} mass. In both histograms, the pion associated with the D^{0} has the opposite charge of the muon. The black histogram has q_{&pi+soft}≠q_{&mu} and the red histogram has q_{&pi+soft}=q_{&mu} (.eps)
- Figure 3: H
_{b} cross section times BR(H_{b}→μD^{0})(.eps)
- Figure 4: H
_{b} cross section from H_{b}→μD^{0} decays (.eps)

- Figure 5: H
_{b} cross section times BR(H_{b}→μD^{*+}) (.eps)
- Figure 6: H
_{b} cross section from H_{b}→μD^{*+} decays (.eps)
- Figure 7: H
_{b} cross section from H_{b}→μD^{0}, H_{b}→μD^{*+}, and H_{b}→J/ψX [2] decays (.eps)
- Figure 8: H
_{b} cross section from H_{b}→μD^{0}, H_{b}→μD^{*+}, and H_{b}→J/ψX [2]decays, with FONLL theory bounds. (.eps)

[2] D. Acosta et al., Phys. Rev. D 71:032001 (2005), hep-ex/0412071