3,423 research outputs found
Luminous red galaxies in the Kilo Degree Survey: selection with broad-band photometry and weak lensing measurements
We use the overlap between multiband photometry of the Kilo-Degree Survey
(KiDS) and spectroscopic data based on the Sloan Digital Sky Survey (SDSS) and
Galaxy And Mass Assembly (GAMA) to infer the colour-magnitude relation of
red-sequence galaxies. We then use this inferred relation to select luminous
red galaxies (LRGs) in the redshift range of over the entire KiDS
Data Release 3 footprint. We construct two samples of galaxies with different
constant comoving densities and different luminosity thresholds. The selected
red galaxies have photometric redshifts with typical photo-z errors of
that are nearly uniform with respect to
observational systematics. This makes them an ideal set of galaxies for lensing
and clustering studies. As an example, we use the KiDS-450 cosmic shear
catalogue to measure the mean tangential shear signal around the selected LRGs.
We detect a significant weak lensing signal for lenses out to
Measurement of Resonance Parameters of Orbitally Excited Narrow B^0 Mesons
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
Measurement of the fraction of t-tbar production via gluon-gluon fusion in p-pbar collisions at sqrt(s)=1.96 TeV
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.
Recommended from our members
Ear care: an update for nurses (part 1)
A healthy ear is vital not just for hearing, but for balance and for full engagement with the community. In the first of two articles, Kat Millward reviews the anatomy of the ear, outlines methods of dealing with cerumen, and discusses methods of assessment and diagnosis
Our ears are essential for both hearing and balance. Up to 4% of the population will have difficulties with their ears relating to impacted cerumen and many of them will present in primary care with ear discomfort or hearing difficulties. In the first of two articles, we review the anatomy and physiology of the ear and cerumen production, followed by a discussion of the key aspects of making an assessment using the SOAP (Subjective, Objective, Assessment, Plan) mnemonic
An iterative consensus-building approach to revising a genetics/genomics competency framework for nurse education in the UK.
AIM: To report a review of a genetics education framework using a consensus approach to agree on a contemporary and comprehensive revised framework. BACKGROUND: Advances in genomic health care have been significant since the first genetics education framework for nurses was developed in 2003. These, coupled with developments in policy and international efforts to promote nursing competence in genetics, indicated that review was timely. DESIGN: A structured, iterative, primarily qualitative approach, based on a nominal group technique. METHOD: A meeting convened in 2010 involved stakeholders in UK nursing education, practice and management, including patient representatives (n = 30). A consensus approach was used to solicit participants' views on the individual/family needs identified from real-life stories of people affected by genetic conditions and the nurses' knowledge, skills and attitudes needed to meet those needs. Five groups considered the stories in iterative rounds, reviewing comments from previous groups. Omissions and deficiencies were identified by mapping resulting themes to the original framework. Anonymous voting captured views. Educators at a second meeting developed learning outcomes for the final framework. FINDINGS: Deficiencies in relation to Advocacy, Information management and Ongoing care were identified. All competencies of the original framework were revised, adding an eighth competency to make explicit the need for ongoing care of the individual/family. CONCLUSION: Modifications to the framework reflect individual/family needs and are relevant to the nursing role. The approach promoted engagement in a complex issue and provides a framework to guide nurse education in genetics/genomics; however, nursing leadership is crucial to successful implementation
Physical education at preschools: practitioners’ and children’s engagements with physical activity and health discourses
This is an Accepted Manuscript of an article published by Taylor & Francis in British Journal of Sociology of Education on December 2013, available online: http://wwww.tandfonline.com/10.1080/01425692.2013.848780This paper focuses on one aspect of a qualitative study concerned with investigating the place and meaning of ‘physical education’ to practitioners and children at three preschools in Scotland. We examine the ways in which the participants engaged with discourses related to physical activity and health in order to construct their subjectivities. Fourteen practitioners and 70 children participated. Research methods employed were observations, interviews with adults, a group drawing and discussion activity with children, and interviews with children. Both the adults’ and children’s talk illustrated the dominance of neoliberal, healthism meanings which position individuals as responsible for their own health. While the children’s talk primarily centred on health as a corporeal notion, the practitioners tended to talk about physical activity and health in both corporeal terms and in relation to the self more holistically. The practitioners also talked about physical activity as a means of regulating children’s behaviour
Top Quark Mass Measurement in the Lepton plus Jets Channel Using a Modified Matrix Element Method
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
Search for Long-Lived Massive Charged Particles in 1.96 TeV \bar{p}p} Collisions
16 pages, 2 figures; Revision to fix PDF errors on some displays/printersWe performed a signature-based search for long-lived charged massive particles (CHAMPs) produced in 1.0 of collisions at TeV, collected with the CDF II detector using a high transverse-momentum () muon trigger. The search used time-of-flight to isolate slowly moving, high- particles. One event passed our selection cuts with an expected background of events. We set an upper bound on the production cross section, and, interpreting this result within the context of a stable scalar top quark model, set a lower limit on the particle mass of 249 GeV/ at 95% C.L.We performed a signature-based search for long-lived charged massive particles produced in 1.0  fb-1 of pp̅ collisions at √s=1.96  TeV, collected with the CDF II detector using a high transverse-momentum (pT) muon trigger. The search used time of flight to isolate slowly moving, high-pT particles. One event passed our selection cuts with an expected background of 1.9±0.2 events. We set an upper bound on the production cross section and, interpreting this result within the context of a stable scalar top-quark model, set a lower limit on the particle mass of 249  GeV/c2 at 95% C.L.Peer reviewe
Search for a Higgs Boson Decaying to Two W Bosons at CDF
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
- …