Measurement of the production of charged pions by protons on a tantalum target
European Physical Journal C 51:4 (2007) 787-824
Abstract:
A measurement of the double-differential cross-section for the production of charged pions in proton-tantalum collisions emitted at large angles from the incoming beam direction is presented. The data were taken in 2002 with the HARP detector in the T9 beam line of the CERN PS. The pions were produced by proton beams in a momentum range from 3 GeV/c to 12 GeV/c hitting a tantalum target with a thickness of 5% of a nuclear interaction length. The angular and momentum range covered by the experiment (100 MeV/c ≤ p< 800 MeV/c and 0.35 rad ≤ θ< 2.15 rad) is of particular importance for the design of a neutrino factory. The produced particles were detected using a small-radius cylindrical time projection chamber (TPC) placed in a solenoidal magnet. Track recognition, momentum determination and particle identification were all performed based on the measurements made with the TPC. An elaborate system of detectors in the beam line ensured the identification of the incident particles. Results are shown for the double-differential cross-sections d 2σ/dpdθ at four incident proton beam momenta (3 GeV/c, 5 GeV/c, 8 GeV/c and 12 GeV/c). In addition, the pion yields within the acceptance of typical neutrino factory designs are shown as a function of beam momentum. The measurement of these yields within a single experiment eliminates most systematic errors in the comparison between rates at different beam momenta and between positive and negative pion production. © 2007 Springer-Verlag / Società Italiana di Fisica.Measurement of the shape of the boson rapidity distribution for pp̄→Z/γ*→e+e-+X events produced at s of 1.96 TeV
Physical Review D - Particles, Fields, Gravitation and Cosmology 76:1 (2007)
Abstract:
We present a measurement of the shape of the boson rapidity distribution for pp̄→Z/γ*→e+e-+X events at a center-of-mass energy of 1.96 TeV. The measurement is made for events with electron-positron mass 71Publisher’s Note: First cross-correlation analysis of interferometric and resonant-bar gravitational-wave data for stochastic backgrounds [Phys. Rev. DPRVDAQ0556-2821 76, 022001 (2007)]
Physical Review D American Physical Society (APS) 76:2 (2007) 029905
Measurement of the top-quark mass using missing ET+jets events with secondary vertex b-tagging at CDF II
Physical Review D - Particles, Fields, Gravitation and Cosmology 75:11 (2007)
Abstract:
We present a measurement of the top-quark mass in pp̄ collisions at s=1.96TeV which uses events with an inclusive signature of missing transverse energy and jets. The event selection is sensitive to tt̄→W+bW- b̄→lνbqq′b̄ independent of the lepton flavor and results in a large acceptance for W→τν decays. All-hadronic tt̄ decays and events with identified electrons or muons are vetoed to provide a statistically independent sample with respect to all previous measurements. The top-quark mass is inferred from the distribution of the scalar sum of all jet transverse energies and the missing transverse energy. Using 311pb-1 of integrated luminosity recorded by the Collider Detector at Fermilab, we measure a top-quark mass mt=172.3-9.6+10.8(stat)±10.8(syst)GeV/c2. While the uncertainty on mt is larger than that of other measurements, the result is statistically uncorrelated with those of other methods and thus can help to reduce the overall mt uncertainty when combined with other existing measurements. © 2007 The American Physical Society.Search for new physics inlepton + photon + X events with929 pb − 1 ofp p ¯ collisions ats = 1.96 TeV
Physical Review D American Physical Society (APS) 75:11 (2007) 112001