3,148 research outputs found

    Measurement of the fraction of t-tbar production via gluon-gluon fusion in p-pbar collisions at sqrt(s)=1.96 TeV

    Get PDF
    We present a measurement of the ratio of t-tbar production cross section via gluon-gluon fusion to the total t-tbar production cross section in p-pbar collisions at sqrt{s}=1.96 TeV at the Tevatron. Using a data sample with an integrated luminosity of 955/pb recorded by the CDF II detector at Fermilab, we select events based on the t-tbar decay to lepton+jets. Using an artificial neural network technique we discriminate between t-tbar events produced via q-qbar annihilation and gluon-gluon fusion, and find Cf=(gg->ttbar)/(pp->ttbar)<0.33 at the 68% confidence level. This result is combined with a previous measurement to obtain the most precise measurement of this quantity, Cf=0.07+0.15-0.07.Comment: submitted to Phys. Rev.

    Measurement of Resonance Parameters of Orbitally Excited Narrow B^0 Mesons

    Get PDF
    We report a measurement of resonance parameters of the orbitally excited (L=1) narrow B^0 mesons in decays to B^{(*)+}\pi^- using 1.7/fb of data collected by the CDF II detector at the Fermilab Tevatron. The mass and width of the B^{*0}_2 state are measured to be m(B^{*0}_2) = 5740.2^{+1.7}_{-1.8}(stat.) ^{+0.9}_{-0.8}(syst.) MeV/c^2 and \Gamma(B^{*0}_2) = 22.7^{+3.8}_{-3.2}(stat.) ^{+3.2}_{-10.2}(syst.) MeV/c^2. The mass difference between the B^{*0}_2 and B^0_1 states is measured to be 14.9^{+2.2}_{-2.5}(stat.) ^{+1.2}_{-1.4}(syst.) MeV/c^2, resulting in a B^0_1 mass of 5725.3^{+1.6}_{-2.2}(stat.) ^{+1.4}_{-1.5}(syst.) MeV/c^2. This is currently the most precise measurement of the masses of these states and the first measurement of the B^{*0}_2 width.Comment: 7 pages, 1 figure, 1 table. Submitted to Phys.Rev.Let

    Search for lepton flavor violating decays of a heavy neutral particle in p-pbar collisions at root(s)=1.8 TeV

    Get PDF
    We report on a search for a high mass, narrow width particle that decays directly to e+mu, e+tau, or mu+tau. We use approximately 110 pb^-1 of data collected with the Collider Detector at Fermilab from 1992 to 1995. No evidence of lepton flavor violating decays is found. Limits are set on the production and decay of sneutrinos with R-parity violating interactions.Comment: Figure 2 fixed. Reference 4 fixed. Minor changes to tex

    Identity work and the `unemployed' worker: age, disability and the lived experience of the older unemployed

    Get PDF
    This article seeks to explore how older individuals negotiate and manage their self-identity in relation to work while situated without paid employment. After reviewing the current positions of the older unemployed in the UK, noting the substantial overlap between age and disability, we turn our attention to conceptualizing the lived experiences of individuals through exploring `identity work' as a means of understanding a non-working work identity. Based upon focus group interviews, our empirical analysis focuses on key dimensions of participants' identity practice and how they sought to manage the following social processes: imposed identities; crafting working identities; and contesting unfavourable working identities.The conclusion contextualizes the findings against a backdrop of increasing individualistic discourses underpinning approaches to employability, closes with the policy implications arising from this study, and makes suggestions for future research agendas. </jats:p

    Exclusionary employment in Britain’s broken labour market

    Get PDF
    There is growing evidence of the problematic nature of the UK’s ‘flexible labour market’ with rising levels of in-work poverty and insecurity. Yet successive Governments have stressed that paid work is the route to inclusion, focussing attention on the divide between employed and unemployed. Past efforts to measure social exclusion have tended to make the same distinction. The aim of this paper is to apply Levitas et al’s (2007) framework to assess levels of exclusionary employment, i.e. exclusion arising directly from an individual’s labour market situation. Using data from the Poverty and Social Exclusion UK survey, results show that one in three adults in paid work is in poverty, or in insecure or poor quality employment. One third of this group have not seen any progression in their labour market situation in the last five years. The policy focus needs to shift from ‘Broken Britain’ to Britain’s broken labour market

    The quality of different types of child care at 10 and 18 months. A comparison between types and factors related to quality.

    Get PDF
    The quality of care offered in four different types of non-parental child care to 307 infants at 10 months old and 331 infants at 18 months old was compared and factors associated with higher quality were identified. Observed quality was lowest in nurseries at each age point, except that at 18 months they offered more learning activities. There were few differences in the observed quality of care by child-minders, grandparents and nannies, although grandparents had somewhat lower safety and health scores and offered children fewer activities. Cost was largely unrelated to quality of care except in child-minding, where higher cost was associated with higher quality. Observed ratios of children to adults had a significant impact on quality of nursery care; the more infants or toddlers each adult had to care for, the lower the quality of the care she gave them. Mothers' overall satisfaction with their child's care was positively associated with its quality for home-based care but not for nursery settings

    Nonhospice Palliative Care Within the Treatment of End‐Stage Liver Disease

    Full text link
    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155544/1/hep31226.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155544/2/hep31226_am.pd

    'Caught Between a Rock and a Hard Place': Anti-discrimination Legislation in the Liberal State and the Fate of the Australian Disability Discrimination Act

    Get PDF
    This article offers a critical analysis of some of the practical implications for disabled people of the Disability Discrimination Act of 1992. Specifically, it raises questions about politics and the role of the law as an instrument of social change?taking greater account of the interests of disabled people?on the one hand, and of the reliance of the social model of disability on a strategy based upon legal rights on the other. The article also suggests that the constraining effects of Australia's constitutional protections of rights and its federal system of government hinder the mildly progressive elements of the Disability Discrimination Act. To illustrate this, the paper employs empirical evidence to suggest that these effects have been exacerbated by the passage of the Human Rights Legislation Amendment Act in 1999

    Search for a Higgs Boson Decaying to Two W Bosons at CDF

    Get PDF
    We present a search for a Higgs boson decaying to two W bosons in ppbar collisions at sqrt(s)=1.96 TeV center-of-mass energy. The data sample corresponds to an integrated luminosity of 3.0 fb-1 collected with the CDF II detector. We find no evidence for production of a Higgs boson with mass between 110 and 200 GeV/c^2, and determine upper limits on the production cross section. For the mass of 160 GeV/c^2, where the analysis is most sensitive, the observed (expected) limit is 0.7 pb (0.9 pb) at 95% Bayesian credibility level which is 1.7 (2.2) times the standard model cross section

    Top Quark Mass Measurement in the Lepton plus Jets Channel Using a Modified Matrix Element Method

    Get PDF
    46 pages, 16 figures. Edited in response to referee comments and resubmitted to Phys. Rev. DWe report a measurement of the top quark mass, m_t, obtained from ppbar collisions at sqrt(s) = 1.96 TeV at the Fermilab Tevatron using the CDF II detector. We analyze a sample corresponding to an integrated luminosity of 1.9 fb^-1. We select events with an electron or muon, large missing transverse energy, and exactly four high-energy jets in the central region of the detector, at least one of which is tagged as coming from a b quark. We calculate a signal likelihood using a matrix element integration method, with effective propagators to take into account assumptions on event kinematics. Our event likelihood is a function of m_t and a parameter JES that determines /in situ/ the calibration of the jet energies. We use a neural network discriminant to distinguish signal from background events. We also apply a cut on the peak value of each event likelihood curve to reduce the contribution of background and badly reconstructed events. Using the 318 events that pass all selection criteria, we find m_t = 172.7 +/- 1.8 (stat. + JES) +/- 1.2 (syst.) GeV/c^2.We report a measurement of the top quark mass, mt, obtained from pp̅ collisions at √s=1.96  TeV at the Fermilab Tevatron using the CDF II detector. We analyze a sample corresponding to an integrated luminosity of 1.9  fb-1. We select events with an electron or muon, large missing transverse energy, and exactly four high-energy jets in the central region of the detector, at least one of which is tagged as coming from a b quark. We calculate a signal likelihood using a matrix element integration method, where the matrix element is modified by using effective propagators to take into account assumptions on event kinematics. Our event likelihood is a function of mt and a parameter JES (jet energy scale) that determines in situ the calibration of the jet energies. We use a neural network discriminant to distinguish signal from background events. We also apply a cut on the peak value of each event likelihood curve to reduce the contribution of background and badly reconstructed events. Using the 318 events that pass all selection criteria, we find mt=172.7±1.8(stat+JES)±1.2(syst)  GeV/c2.Peer reviewe
    corecore