Tests of enhanced leading order QCD in W boson plus jets events from 1.8 TeV p̄p collisions
Physical Review D - Particles, Fields, Gravitation and Cosmology 63:7 (2001) 720031-7200329
Abstract:
We present a study of events with W bosons and hadronic jets produced in p̄p collisions at a center of mass energy of 1.8 TeV. The data consist of 51400 W → e ν decay candidates from 108 pb-1 of integrated luminosity collected using the CDF detector at the Fermilab Tevatron collider. Cross sections and jet production properties have been measured for W + ≥ 1 to ≥ 4 jet events. The data compare well to predictions of leading-order QCD matrix element calculations with added gluon radiation and simulated parton fragmentation.Rate measurement of D(0)-->K+pi(-)pi(0) and constraints on D(0) -- D(0) mixing.
Phys Rev Lett 87:7 (2001) 071802
Abstract:
We present an observation and time-integrated rate measurement of the decay D(0)-->K(+)pi(-)pi(0) produced in 9 fb(-1) of e(+)e(-) collisions near the Upsilon(4S) resonance. The signal is inconsistent with an upward fluctuation of the background by 4.9 standard deviations. We measured the time-integrated rate of D(0)-->K(+)pi(-)pi(0) normalized to the rate of D(0)-->K(+)pi(-)pi(0) to be 0.0043(+0.0011)(-0.0010) (stat)+/-0.0007 (syst). This decay can be produced by doubly Cabibbo-suppressed decays or by the D(0) evolving into a D(0) through mixing, followed by a Cabibbo-favored decay to K(+)pi(-)pi(0). We also found the CP asymmetry A = (9(+25)(-22))% be consistent with zero.A 51ÁÔÆæÈë¿Ú of B0 -> J/psi K(*)0 pi+ pi- Decays with the Collider Detector at Fermilab
ArXiv hep-ex/0108022 (2001)
Experimental investigation of the two-photon widths of the chi(c0) and the chi(c2) mesons.
Phys Rev Lett 87:6 (2001) 061801
Abstract:
Using 12.7 fb(-1) of data collected with the CLEO detector at CESR, we observed two-photon production of the cc states chi(c0) and chi(c2) in their decay to pi(+)pi(-)pi(+)pi(-). We measured gamma(gammagamma)(chi(c))xB(chi(c)-->pi(+)pi(-)pi(+)pi(-)) to be 75+/-13(stat)+/-8(syst) eV for the chi(c0) and 6.4+/-1.8(stat)+/-0.8(syst) eV for the chi(c2), implying gamma(gammagamma)(chi(c0)) = 3.76+/-0.65(stat)+/-0.41(syst)+/-1.69(br) keV and gamma(gammagamma)(chi(c2)) = 0.53+/-0.15(stat)+/-0.06(syst)+/-0.22(br) keV. Also, cancellation of dominant experimental and theoretical uncertainties permits a precise comparison of gamma(gammagamma)(chi(c0))/gamma(gammagamma)(chi(c2)), evaluated to be 7.4+/-2.4(stat)+/-0.5(syst)+/-0.9(br), with QCD-based predictions.Search for New Heavy Particles in the WZ Final State in Proton Anti-Proton Collisions at Sqrt{s} = 1.8 TeV
ArXiv hep-ex/0108004 (2001)