263 research outputs found

    Lifetime Differences, direct CP Violation and Partial Widths in D0 Meson Decays to K+K- and pi+pi-

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    We describe several measurements using the decays D0->K+K- and pi+pi-. We find the ratio of partial widths, Gamma(D0->K+K-)/Gamma(D0->pi+pi-), to be 2.96+/-0.16+/-0.15, where the first error is statistical and the second is systematic. We observe no evidence for direct CP violation, obtaining A_CP(KK) = (0.0+/-2.2+/-0.8)% and A_CP(pipi = (1.9+/-3.2+/-0.8)%. In the limit of no CP violation we measure the mixing parameter y_CP = -0.012+/-0.025+/-0.014 by measuring the lifetime difference between D0->K+ K- or pi+pi- and the CP neutral state, D0->K-pi+. We see no evidence for mixing.Comment: 14 pages postscript, also available through http://w4.lns.cornell.edu/public/CLNS, submitted to PRD, Rapid Communicatio

    Measurement of the Mass Splittings between the bbˉχb,J(1P)b\bar{b}\chi_{b,J}(1P) States

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    We present new measurements of photon energies and branching fractions for the radiative transitions: Upsilon(2S)->gamma+chi_b(J=0,1,2). The masses of the chi_b states are determined from the measured radiative photon energies. The ratio of mass splittings between the chi_b substates, r==(M[J=2]-M[J=1])/(M[J=1]-M[J=0]) with M the chi_b mass, provides information on the nature of the bbbar confining potential. We find r(1P)=0.54+/-0.02+/-0.02. This value is in conflict with the previous world average, but more consistent with the theoretical expectation that r(1P)<r(2P); i.e., that this mass splittings ratio is smaller for the chi_b(1P) triplet than for the chi_b(2P) triplet.Comment: 11 page postscript file, postscript file also available through http://w4.lns.cornell.edu/public/CLN

    Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set

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    We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012

    Status of the CCD development for the Dark Energy Spectroscopic Instrument

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    We describe improvements in CCD performance that have been achieved on 4k×4k, (15 μm)2-pixel, fully depleted CCDs for the Dark Energy Spectroscopic Instrument (DESI) [1]. With respect to our previous work on CCDs for the Dark Energy Camera and the Baryon Oscillation Spectroscopic Survey, our goals for the DESI CCD development were to improve read noise and quantum efficiency, improve the astrometric precision, and decrease pixel-size variations. We report experimental results on recently fabricated CCDs to be used in DESI

    Reduction of cardiovascular risk in patients with metabolic syndrome in a community health center after a pharmaceutical care program of pharmacotherapy follow-up

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    The objective of this study was to determine the impact of a pharmaceutical care (PC) program in a sample of public outpatients with metabolic syndrome (MS) who were being treated in Brazil's health system; the patients were randomized into PC or standard care. The pharmacotherapy follow-up (PF) was performed in a total of 120 patients with type 2 diabetes for 6 months. Adherence to treatment (measured with the Morisky test), negative outcomes associated with medication (NOM) and anthropometric and biochemical parameters were measured before and after PF. The Framingham scoring method was used to estimate changes in 10-year coronary heart disease risk scores in all patients. Ninety-six of 120 patients had characteristics of MS and were randomized into two groups (G): the control group (CG: 36) and the intervention group (IG: 38). Among the MS patients, 100% were taking a glucose-lowering drug; many were also taking anti-hypertensive drugs (CG: 72%; IG: 73%), and some patients were also taking hypolipemic drugs (CG: 12.0%; IG: 14.7%). Only 20.7% of the IG patients were considered adherent to their prescribed drugs. In the CG, an increase of coronary heart disease (CHD) risk (22±2 to 26±3; pO objetivo deste estudo foi o de determinar o impacto de um Programa de atenção Farmacêutica (AF) em uma amostra de pacientes ambulatoriais de Sistema Público de Saúde do Brasil portadores de Síndrome Metabólica, randomizados em AF ou atenção à saúde usual. Realizou-se o seguimento farmacoterapêutico com 120 pacientes com diabetes tipo 2 durante seis meses. Avaliou-se o nível de aderência ao tratamento (teste Morisky), resultados clínicos negativos associados a medicamentos (RNM), parâmetros bioquímicos e antropométricos, antes e após o seguimento. O método de Framingham foi usado para calcular as variações no risco de doenças coronarianas em 10 anos em todos os pacientes. Dos 120 pacientes, 96 tiveram características de SM e foram então randomizados em dois grupos (G): Controle (GC: 36) e Intervenção (GI: 38). Entre os pacientes com SM, 100% faziam uso de medicamentos para diminuir a glicose, anti-hipertensivos (GC: 72%; GI: 73%) e hipoglicemiantes (GC: 12.0%; GI: 14.7%). Apenas 20,7% do GI foram considerados aderentes aos fármacos prescritos. No GC foi observado aumento do risco de Doença Arterial Coronariana (DAC) (22±2 para 26±3; p<0,05), enquanto no GI foi observado redução (22±2 para 14±2%; p<0,01). O Programa de AF para pacientes com SM monitorados na atenção primária do Sistema de Saúde Pública brasileiro melhora o funcionamento do serviço resultando na melhoria clínica dos pacientes com redução do risco de doença cardiovascular em um período de dez anos

    Combination of searches for Higgs boson pairs in pp collisions at \sqrts = 13 TeV with the ATLAS detector

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    This letter presents a combination of searches for Higgs boson pair production using up to 36.1 fb(-1) of proton-proton collision data at a centre-of-mass energy root s = 13 TeV recorded with the ATLAS detector at the LHC. The combination is performed using six analyses searching for Higgs boson pairs decaying into the b (b) over barb (b) over bar, b (b) over barW(+)W(-), b (b) over bar tau(+)tau(-), W+W-W+W-, b (b) over bar gamma gamma and W+W-gamma gamma final states. Results are presented for non-resonant and resonant Higgs boson pair production modes. No statistically significant excess in data above the Standard Model predictions is found. The combined observed (expected) limit at 95% confidence level on the non-resonant Higgs boson pair production cross-section is 6.9 (10) times the predicted Standard Model cross-section. Limits are also set on the ratio (kappa(lambda)) of the Higgs boson self-coupling to its Standard Model value. This ratio is constrained at 95% confidence level in observation (expectation) to -5.0 &lt; kappa(lambda) &lt; 12.0 (-5.8 &lt; kappa(lambda) &lt; 12.0). In addition, limits are set on the production of narrow scalar resonances and spin-2 Kaluza-Klein Randall-Sundrum gravitons. Exclusion regions are also provided in the parameter space of the habemus Minimal Supersymmetric Standard Model and the Electroweak Singlet Model. For complete list of authors see http://dx.doi.org/10.1016/j.physletb.2019.135103</p
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