1,689 research outputs found

    Tests of QCD in W and Z Production at Tevatron

    Get PDF
    We present measurements of the production cross sections times leptonic branching fractions and the transverse momentum distributions of WW and ZZ bosons in ppˉp\bar{p} collisions at s=1.8\sqrt{s}=1.8 TeV using data collected with the D{\O}detector at the Fermilab Tevatron ppˉp\bar{p} collider. A preliminary measurement of the WW charge asymmetry is also presented.Comment: 25 pages in a uucoded PS fil

    Tests of QCD in W and Z production at Tevatron

    Get PDF
    We present measurements of the production cross sections times leptonic branching fractions and the transverse momentum distributions of W and Z bosons in p\bar{p} collisions at \sqrt{s}=1.8~TeV using data collected with the D\O\ detector at the Fermilab Tevatron p\bar{p} collider. A preliminary measurement of the W charge asymmetry is also presented

    Warped Phenomenology

    Full text link
    We explore the phenomenology associated with the recently proposed localized gravity model of Randall and Sundrum where gravity propagates in a 5-dimensional non-factorizable geometry and generates the 4-dimensional weak-Planck scale hierarchy by an exponential function of the compactification radius, called a warp factor. The Kaluza-Klein tower of gravitons which emerge in this scenario have strikingly different properties than in the factorizable case with large extra dimensions. We derive the form of the graviton tower interactions with the Standard Model fields and examine their direct production in Drell-Yan and dijet events at the Tevatron and LHC as well as the KK spectrum line-shape at high-energy linear \epem colliders. In the case where the first KK excitation is observed, we outline the procedure to uniquely determine the parameters of this scenario. We also investigate the effect of KK tower exchanges in contact interaction searches. We find that present experiments can place meaningful constraints on the parameters of this model.Comment: 14 pages, LaTex, 3 fig

    Window on Higgs Boson: Fourth Generation bb^\prime Decays Revisited

    Full text link
    Direct and indirect searches of the Higgs boson suggest that 113 GeV mH\lesssim m_H \lesssim 170 GeV is likely. With the LEP era over and the Tevatron Run II search via ppˉWH+Xp\bar p \to WH+X arduous, we revisit a case where WHWH or ZH+ZH + jets could arise via strong bbˉb^\prime\bar b^\prime pair production. In contrast to 10 years ago, the tight electroweak constraint on tt^\prime--bb^\prime (hence tt^\prime--tt) splitting reduces FCNC bbZb^\prime\to bZ, bHbH rates, making bcWb^\prime\to cW naturally competitive. Such a "cocktail solution" is precisely the mix that could evade the CDF search for bbZb^\prime\to bZ, and the bb^\prime may well be lurking below the top. In light of the Higgs program, this two-in-one strategy should be pursued.Comment: 4 pages, RevTex, 4 eps figures, One more figure, version to be published in Phys. Rev.

    Spectrophotometric determination of Phenylephrine hydrochloride and Salbutamol sulphate drugs in pharmaceutical preparations using diazotized Metoclopramide hydrochloride

    Get PDF
    A spectrophotometric method has been proposed for the determination of two drugs containing phenol group [phenylephrine hydrochloride (PHP) and salbutamol sulphate (SLB)] in pharmaceutical dosage forms. The method is based on the diazotization reaction of metoclopramide hydrochloride (MCP) and coupling of the diazotized reagent with drugs in alkaline medium to give intense orange colored product (?max at 470 nm for each of PHP and SLB). Variable parameters such as temperature, reaction time and concentration of the reactants have been analyzed and optimized. Under the proposed optimum condition, Beer’s law was obeyed in the concentration range of 1-32 and 1-14 ?g mL-1 for PHP and SLB, respectively. The limit of detection (LOD) and limit of quantification (LOQ) for each of PHP and SLB were 0.60, 0.52 ?g mL-1 and 2.02, 1.72 ?g mL-1, respectively. No interference was observed from common excipients present in pharmaceutical preparations. The good correlation coefficients and low relative standard deviation assert the applicability of this method. The suggested method was further applied for the determinations of drugs in commercial pharmaceutical preparations, which was compared statistically with reference methods by means of t- test and F- test and were found not to differ significantly at 95% confidence level. The procedure was characterized by its simplicity with accuracy and precision

    ZZγZZ\gamma and ZγγZ\gamma\gamma couplings in γe\gamma e collision with polarized beams

    Full text link
    The potential of γ\gammae mode of linear e+ee^{+}e^{-} collider to probe ZZγZZ\gamma and ZγγZ\gamma\gamma vertices is investigated through the Z boson production from the procees γeZe\gamma e\to Z e. Considering the longitudinal and transverse polarization states of the Z boson and incoming polarized beams we find the 95% C.L. limits on the form factors h3Zh_{3}^{Z}, h4Zh_{4}^{Z}, h3γh_{3}^{\gamma} and h4γh_{4}^{\gamma} with integrated luminosity 500fb1fb^{-1} and s=\sqrt{s}=0.5, 1, 1.5 TeV energies. It is shown that the polarization can improve sensitivities by factors 2-3 depending on the energy.Comment: 12 pages, 8 EPS figure

    Search for Light Top Squarks with the D0 Detector

    Get PDF
    corecore