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Associated production of a W or Z boson with bottom quarks at the Tevatron and the LHC

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 نشر من قبل Doreen Wackeroth
 تاريخ النشر 2010
  مجال البحث
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We present total and differential cross sections for W b anti-b and Z b anti-b production at the CERN Large Hadron Collider including Next-to-Leading Order (NLO) QCD corrections and full bottom-quark mass effects. We discuss the scale uncertainty of the total cross sections due to the residual renormalization- and factorization-scale dependence of the truncated perturbative series. We also discuss b-quark mass effects in kinematic distributions by comparing with a calculation that considers massless bottom quarks, as implemented in the Monte Carlo program MCFM. The effects of a non-zero bottom-quark mass (m_b) cannot be neglected in phase-space regions where the relevant kinematic observable, such as the transverse momentum of the bottom quarks or the invariant mass of the bottom-quark pair, are of the order of m_b. Finally, we present the result of a detailed comparison of NLO QCD predictions for W+b-jet production with one or two jets with Tevatron data.



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