Blessed plots for the b and c content of inclusive jets analysis

In this analysis we attempt to measure the bottom and charm-jet fractions in the Run 1A Inclusive jet 20 and jet 50 samples. We have used the SVX b tagging algorithm (JETVTX) to identify(TAG) a sample of jets with displaced vertices. By fitting the observed lifetime distribution in data to a sample of tagged jets from Monte Carlo, we can measure the fraction of jets that contain at least 1 bottom or charm quark.
Contact person: Phillip Koehn pkoehn@fnald.fnal.gov


The Tagging Efficiency Scale Factor

The following plots describe the scale factor that takes into account the differences in the secondary vertex tagging efficiencies between data and Monte Carlo simulation.
  • sf_j3q1_tgbl.ps---The upper plot shows a comparison of the data and HERWIG MC taggable rate in the jet_50 sample as a function of Et. The lower plot is the corresponding data/MC scale factor.
  • sf_j4q1_tgbl.ps---The upper plot shows a comparison of the data and HERWIG MC taggable rate in the jet_20 sample as a function of Et. The lower plot is the corresponding data/MC scale factor.
  • sf_ice_data_mc_tag.ps---The tagging efficiency as a function of jet Et. A comparison of the two tagging methods for the inclusive electron data are shown in the upper plot. The lower plot shows the two methods in the b-->eX HERWIG Monte Carlo.
  • sf_tag_cor.ps---Scale factor calculated with weighted averages of the two tagging methods as a function of jet Et. In the upper plot, the weighted average of the two tagging efficiencies in data(open points) is compared with Monte Carlo(solid points). The lower plot shows the scale factor. The solid line is the resultant constant fit, and the 2 dashed lines are the $\pm 1\sigma$ uncertainty in the fit.
  • sf_ice_shape.ps---Comparison of tagged electron-jet variables. Data(solid points) and Monte Carlo(histograms) are normalized to unit area.
  • sf_fbc_et_sys_her.ps---Fraction of b and c jets as a function of Et after the tagging efficiencies are corrected with the scale factor. The data(points) are compared with gen-level HERWIG predictions for b(lower contour) and c(upper contour). The open(solid) points indicate the jet_50(jet_20) data. Also plotted are the b jet fractions as measured with double-tagged events. Errors on data points are correlated. The inner error bars are the statistical uncertainty, the outer error bars are the statistical and the systematic uncertainties added in quadrature.
  • sf_fbc_et_sys_pyt.ps---Same as above but comparison is made with Pythia generator-level Monte Carlo.
  • sf_fbc_et_sys_her_wavg.ps---The weighted average of F_b(F_c) measured in the jet_50 and jet_20 samples.
  • sf_fbc_et_sys_pyt_wavg.ps---Same as above but comparison is made with Pythia generator-level Monte Carlo.

    Last updated 13 July, 1996

    suggestions or contributions ? contact pkoehn@fnald.fnal.gov