JetEtmissApproved2010JetPropertyPlots

[Jet momentum before pile-up corrections] Measurements of the impact of pile-up on the transverse momentum of jets constructed from uncalibrated topological clusters as a function of the number of interactions in the event, Npv, while classifying these jets by matching to track-jets formed from only hard-scatter particles. The most probable value from a Landau + Gauss fit as a function of Npv is used in order to determine the effective offset due to pile-up. eps file

[Jet momentum after pile-up corrections] Measurements of the transverse momentum of jets constructed from uncalibrated topological clusters, but after pile-up corrections as a function of the number of interactions in the event, Npv, while classifying these jets by matching to track-jets formed from only hard-scatter particles. Jets are corrected using tower-based offset correction for various track-jet bins. The resulting systematic uncertainty is approximately 100 MeV (120 MeV) per vertex for anti-kt jets with R=0.6 tower (topological cluster) jets in the central region, up to |eta|<1.9. eps file

[Correction of the jet shapes for events with 2 vertices] The differential energy density in a jet is measured in annuli around the jet axis, rho(r) normalized by the total pt in a cone of R=0.7 around the jet, Psi(0.7). The measurement is performed for events with more than one reconstructed vertex before and after the tower-based offset correction is applied. The shape of jets in the rapidity range 1.2<|eta|<2.1 is compared before the offset corrections for events with Npv=1 and 2. In events with 2 reconstructed vertices, differences up to 35% just outside the jet, and 20% at the edge of the jet are corrected. eps file

[Correction of the jet shapes for events with 3 vertices] The differential energy density in a jet is measured in annuli around the jet axis, rho(r) normalized by the total pt in a cone of R=0.7 around the jet, Psi(0.7). The measurement is performed for events with more than one reconstructed vertex before and after the tower-based offset correction is applied. The shape of jets in the rapidity range 1.2<|eta|<2.1 is compared before the offset corrections for (events with Npv=1 and 2. In events with 3 reconstructed vertices, differences up to 70% just outside the jet, and 40%at the edge of the jet are corrected. eps file

[Calorimeter jet mass vs track jet mass] The mean calorimeter jet mass as a function of the mass of jets built using only tracking information, for anti-kt R=1.0 jets constructed from locally calibrated (LC) clusters. Jets are selected to be within the range |eta|<1.0. Prior to pile-up filtering using the jet-vertex fraction, or JVF, calorimeter jets are observed to have a close dependence on the track-jet mass that rises at low track-jet mass. This rise is reduced compared to events with no additional reconstructed vertices. eps file

[Jet mass vs jet momentum] The mean jet mass as a function of jet pT for wide anti-kt R=1.0 jets constructed from locally calibrated (LC) clusters. Jets are selected to be within the range |eta|<1.0. Prior to pile-up filtering using the jet-ver tex fraction, or JVF, jets are observed to have a jet mass approximately 10% higher than events with only a single primary vertex (Npv=1). After JVF selection, the agreement with events having no additonal interactions is within a few %. eps file

[Z distribution of subjets] The z of the last splitting, defined by the ratio of the second hardest sub-jet to the pT of the parent jet. A parent anti-kt R=1.0 jet is reclustered using using the kt algorithm with a resolution parameter of R=0.3 for jets constructed from locally calibrated (LC) clusters. eps file

[Subjet dR] The z of the last splitting, defined by the ratio of the second hardest sub-jet to the pT of the parent jet. A parent anti-kt R=1.0 jet is re-clustered using using the kt algorithm with a resolution parameter of R=0.3 for jets constructed from locally calibrated (LC) clusters. eps file