Measurement of the Top Quark Mass using Quantities with Minimal Dependence on the Jet Energy Scale

We present three measurements of the top quark mass in the lepton plus jets channel with 1.9fb of data using quantities with minimal dependence on the jet energy scale in the lepton plus jets channel at CDF. One measurement uses the mean transverse decay length of b-tagged jets (L2d) to determine the top mass, another uses the transverse momentum of the lepton (LepPt) to determine the top mass, and a third measurement uses both variables simultaneously. Using the L2d variable we measure a top mass of (176.7 −8.9 (stat) ± 3.4(syst)) GeV/c , using the LepPt variable we measure a top mass of (173.5 −9.1 (stat) ± 4.2(syst)) GeV/c, and doing the combined measurement using both variables we arrive at a top mass result of (175.3 ± 6.2(stat) ± 3.0(syst)) GeV/c. Since some of the systematic uncertainties are statistically limited, these results are expected to improve significantly if more data is added at the Tevatron in the future, or if the measurement is done at the LHC.