Heavy flavor properties of jets produced in pp̄ interactions at √s = 1.8 TeV
Physical Review D 69:7 (2004)
Abstract:
We present a detailed examination of the heavy flavor properties of jets produced at the Fermilab Tevatron collider. The data set, collected with the Collider Detector at Fermilab, consists of events with two or more jets with transverse energy EMeasurement of the average time-integrated mixing probability of b-flavored hadrons produced at the Fermilab Tevatron
Physical Review D - Particles, Fields, Gravitation and Cosmology 69:1 (2004)
Abstract:
We have measured the number of like-sign (LS) and opposite-sign (OS) lepton pairs arising from double semileptonic decays of b and [Formula Presented] hadrons, pair produced at the Fermilab Tevatron collider. The data samples were collected with the Collider Detector at Fermilab during the 1992–1995 collider run by triggering on the existence of [Formula Presented] or [Formula Presented] candidates in an event. The observed ratio of LS to OS dileptons leads to a measurement of the average time-integrated mixing probability of all produced b-flavored hadrons which decay weakly, [Formula Presented] that is significantly larger than the world average [Formula Presented] © 2004 The American Physical Society.Search for new particles in the two-jet decay channel with the DØ detector
Physical Review D Particles Fields Gravitation and Cosmology 69:11 (2004)
Abstract:
We present the results of a search for the production of new particles decaying into two jets in [Formula Presented]collisions at [Formula Presented] using the DØ 1992–1995 data set corresponding to [Formula Presented] We exclude at the 95% confidence level the production of excited quarks [Formula Presented] with masses below 775 GeV/[Formula Presented] the most restrictive limit to date. We also exclude standard-model-like [Formula Presented][Formula Presented] bosons with masses between 300 and 800 GeV/[Formula Presented](400 and 640 GeV/[Formula Presented] A [Formula Presented]boson with mass [Formula Presented] has been excluded by previous measurements, and our lower limit is therefore the most stringent to date. © 2004 The American Physical Society.Underlying event in hard interactions at the Fermilab Tevatron [Formula Presented] collider
Physical Review D - Particles, Fields, Gravitation and Cosmology 70:7 (2004)
Abstract:
For comparison of inclusive jet cross sections measured at hadron-hadron colliders to next-to-leading order (NLO) parton-level calculations, the energy deposited in the jet cone by spectator parton interactions must first be subtracted. The assumption made at the Tevatron is that the spectator parton interaction energy is similar to the ambient level measured in minimum bias events. In this paper, we test this assumption by measuring the ambient charged track momentum in events containing large transverse energy jets at [Formula Presented] and [Formula Presented] and comparing this ambient momentum with that observed both in minimum bias events and with that predicted by two Monte Carlo models. Two cones in [Formula Presented] space are defined, at the same pseudorapidity, [Formula Presented], as the jet with the highest transverse energy ([Formula Presented]), and at [Formula Presented] in the azimuthal direction, [Formula Presented]. The total charged track momentum inside each of the two cones is measured. The minimum momentum in the two cones is almost independent of [Formula Presented] and is similar to the momentum observed in minimum bias events, whereas the maximum momentum increases roughly linearly with the jet [Formula Presented] over most of the measured range. This study was carried out using data from the CDF detector taken during Run 1 (1994-1995). The study will help improve the precision of comparisons of jet cross section data and NLO perturbative QCD predictions. The distribution of the sum of the track momenta in the two cones is also examined for five different [Formula Presented] bins. The HERWIG and PYTHIA Monte Carlo generators are reasonably successful in describing the data, but neither can describe completely all of the event properties. © 2004 The American Physical Society.A precision measurement of the mass of the top quark
NATURE 429:6992 (2004) 638-642