Measurement of the ratio of the $p\bar{p}\to W$+$c$-jet cross section to the inclusive $p\bar{p}\to W$+jets cross section

G. OTERO Y GARZON, R. PIEGAIA, ET. AL. , THE DZERO COLLABORATION

PHYSICS LETTERS B

ELSEVIER SCIENCE BV

Año: 2008 p. 66623 - 66630

0370-2693

We present a measurement of the fraction of inclusive $W$+jets events produced with net charm quantum number $pm1$, denoted $W$+$c$-jet, in $par{p}$ collisions at $sqrt{s}=1.96$ TeV using approximately 1~fb$^{-1}$ of data collected by the D0 detector at the Fermilab Tevatron Collider. We identify the $W$+jets events via the leptonic $W$ boson decays. Candidate $W$+$c$-jet events are selected by requiring a jet containing a muon in association with a reconstructed $W$ boson and exploiting the charge correlation between this muon and $W$ boson decay lepton to perform a nearly model-independent background subtraction. We measure the fraction of $W$+$c$-jet events in the inclusive $W$+jets sample for jet $p_{T}>20$ GeV and pseudorapidity $|eta|<2.5$ to be 0.074$pm0.019$(stat.)$pm^{0.012}_{0.014}$(syst.), in agreement with theoretical predictions. The probability that background fluctuations could produce the observed fraction of $W$+$c$-jet events is estimated to be $2.5 imes 10^{-4}$, which corresponds to a 3.5 $sigma$ statistical significance.