A Measurement of the Ratio of Inclusive Cross Sections pbarp->Zb/pbarp->Zj at sqrt(s)=1.96 TeV

THE DZERO COLLABORATION, GUSTAVO OTERO Y GARZON

PHYSICAL REVIEW LETTERS

Año: 2005 p. 1618011 - 1618017

0031-9007

Using the data collected with the D0 detector at sqrt(s) = 1:96 TeV, for integrated luminosities of about 180 pb-1, we have measured the ratio of inclusive cross sections for ppbar à Z + b-jet to ppbar à Z + jet production. The inclusive Z + b-jet reaction is an important background to searches for the Higgs boson in associated ZH production at the Fermilab Tevatron collider. Our measurement is the first of its kind, and relies on the Z à e+ e- and Z à m+ m-. The combined measurement of the ratio yields 0.021 ± 0.005 for hadronic jets with transverse momenta pT > 20 GeV/c and pseudorapidities |h| < 2.5, consistent with next-to-leading-order predictions of the standard model.