45 research outputs found

    Measurement of the branching fraction and CP content for the decay B(0) -> D(*+)D(*-)

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    This is the pre-print version of the Article. The official published version can be accessed from the links below. Copyright @ 2002 APS.We report a measurement of the branching fraction of the decay B0→D*+D*- and of the CP-odd component of its final state using the BABAR detector. With data corresponding to an integrated luminosity of 20.4  fb-1 collected at the Υ(4S) resonance during 1999–2000, we have reconstructed 38 candidate signal events in the mode B0→D*+D*- with an estimated background of 6.2±0.5 events. From these events, we determine the branching fraction to be B(B0→D*+D*-)=[8.3±1.6(stat)±1.2(syst)]×10-4. The measured CP-odd fraction of the final state is 0.22±0.18(stat)±0.03(syst).This work is supported by DOE and NSF (USA), NSERC (Canada), IHEP (China), CEA and CNRS-IN2P3 (France), BMBF (Germany), INFN (Italy), NFR (Norway), MIST (Russia), and PPARC (United Kingdom). Individuals have received support from the A.P. Sloan Foundation, Research Corporation, and Alexander von Humboldt Foundation

    Measurement of D-s(+) and D-s(*+) production in B meson decays and from continuum e(+)e(-) annihilation at √s=10.6 GeV

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    This is the pre-print version of the Article. The official published version can be accessed from the links below. Copyright @ 2002 APSNew measurements of Ds+ and Ds*+ meson production rates from B decays and from qq̅ continuum events near the Υ(4S) resonance are presented. Using 20.8 fb-1 of data on the Υ(4S) resonance and 2.6 fb-1 off-resonance, we find the inclusive branching fractions B(B⃗Ds+X)=(10.93±0.19±0.58±2.73)% and B(B⃗Ds*+X)=(7.9±0.8±0.7±2.0)%, where the first error is statistical, the second is systematic, and the third is due to the Ds+→φπ+ branching fraction uncertainty. The production cross sections σ(e+e-→Ds+X)×B(Ds+→φπ+)=7.55±0.20±0.34pb and σ(e+e-→Ds*±X)×B(Ds+→φπ+)=5.8±0.7±0.5pb are measured at center-of-mass energies about 40 MeV below the Υ(4S) mass. The branching fractions ΣB(B⃗Ds(*)+D(*))=(5.07±0.14±0.30±1.27)% and ΣB(B⃗Ds*+D(*))=(4.1±0.2±0.4±1.0)% are determined from the Ds(*)+ momentum spectra. The mass difference m(Ds+)-m(D+)=98.4±0.1±0.3MeV/c2 is also measured.This work was supported by DOE and NSF (USA), NSERC (Canada), IHEP (China), CEA and CNRS-IN2P3 (France), BMBF (Germany), INFN (Italy), NFR (Norway), MIST (Russia), and PPARC (United Kingdom). Individuals have received support from the Swiss NSF, A. P. Sloan Foundation, Research Corporation, and Alexander von Humboldt Foundation

    Measurement of the Ratio of b Quark Production Cross Sections in Antiproton-Proton Collisions at 630 GeV and 1800 GeV

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    We report a measurement of the ratio of the bottom quark production cross section in antiproton-proton collisions at 630 GeV to 1800 GeV using bottom quarks with transverse momenta greater than 10.75 GeV identified through their semileptonic decays and long lifetimes. The measured ratio sigma(630)/sigma(1800) = 0.171 +/- .024 +/- .012 is in good agreement with next-to-leading order (NLO) quantum chromodynamics (QCD)

    Informações sobre homicídios e sua integração com o setor saúde e segurança pública Linking of information from health and security databases on homicides

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    OBJETIVO: O aumento verificado nas taxas de homicídios aponta para a necessidade de melhorar a compreensão do problema. O objetivo do presente trabalho foi conhecer as informações adicionais acerca da mortalidade por homicídios provenientes de diferentes fontes de dados. MÉTODOS: Foram analisados os dados de homicídios entre residentes do Município de São Paulo, para o segundo semestre de 2001 obtidos nas declarações de óbito, laudos de necropsia e boletins de ocorrência policial. As informações foram analisadas sob a forma de números absolutos, proporções e coeficientes. Para a verificação de diferenças estatísticas foi utilizado o teste do qui-quadrado de Pearson. RESULTADOS: O coeficiente de homicídios foi 57,2/100.000, sendo que os valores mais altos foram encontrados entre os homens na faixa de 15 a 29 anos. O percentual do uso de armas de fogo foi 88,6%, mais alto entre homens que em mulheres. A localização anatômica de lesões mais freqüentes foi a cabeça (68,9%). Entre as vítimas que tiveram o exame toxicológico realizado, 42,5% tinham feito uso de álcool (44% para os homens e 24% nas mulheres). Há maior concentração de ocorrências nos finais de semana no horário noturno. Em 74,6% dos óbitos, as vítimas residiam próximas ou no mesmo local de ocorrência do evento. CONCLUSÕES: Os achados do estudo apontam que a integração de dados permite melhorar a qualidade da informação, contribuindo para a compreensão dos homicídios.<br>OBJECTIVE: Increased homicide rates in the city of Sao Paulo, Brazil, in the last two decades points out to the need for better understanding this subject. The purpose of the present study was to link information about homicide from different sources of data. METHODS: Homicide data from death certificates, medical examiners and police records of residents in the city of Sao Paulo was linked for the second semester of 2001. Variables about victims, risk factors and homicide circumstances were analyzed using absolute numbers, proportions and coefficients. Statistical differences were tested using Pearson's Chi-square test. RESULTS: Homicide crude rate was 57.2/100,000. Higher rates were observed among men aged 15 to 29 years (56.0% of all cases). The proportion of firearm-related homicides was 88.6%, higher among men than women. Most injuries were to the head (68.9%). Among the victims who underwent to drug screening, 42.5% had high blood alcohol concentrations (44.0% for men and 24.0% for women). Most events occurred at night during weekends and it was found a high correlation (74.6%) between the victim's place of residence and event location. CONCLUSIONS: The study findings highlight that linking information provides better quality of data and allows for better understanding of homicides

    Anos potenciais de vida perdidos por mulheres vítimas de homicídio na cidade do Recife, Pernambuco, Brasil Years of potential life lost by female homicide victims in Recife, Pernambuco State, Brazil

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    Estudo epidemiológico, transversal, objetivando calcular os anos potenciais de vida perdidos por mulheres vítimas de homicídio na cidade do Recife, Pernambuco, Brasil, no quinquênio 2003-2007. Utilizou-se de um banco de dados da Gerência Operacional de Informação de Mortalidade e Natalidade da Secretaria de Saúde do Recife, e foram revisadas todas as declarações de óbitos das vítimas de homicídio, com idade fértil no quinquênio analisado. Os resultados revelaram que houve 12.120 anos potenciais de vida perdidos, no período, por mulheres jovens, negras (88%), de escolaridade desconhecida (78,2%), solteiras (80%), mortas na Região Político-administrativa III, que foram assassinadas com uso de arma de fogo, no próprio domicílio. A taxa de mortalidade específica, no período, correspondeu a 10,8 por 100 mil mulheres em idade fértil. Os 43,3 anos de vida perdidos por cada vítima refletem, entre outros aspectos, as características do município, relativas ao nível de pobreza, desemprego, densidade populacional, instabilidade residencial, desigualdade social, que expõem seus habitantes a crises sociais, crimes e violência.<br>This cross-sectional epidemiological study aimed to calculate the potential years of life lost by female homicide victims in Recife, Pernambuco State, Brazil, in 2003-2007. A database was used from the Operational Division for Information on Births and Deaths under the Recife Municipal Health Department. All death certificates for childbearing-age women were reviewed for the five-year period. The results showed a total of 12,120 potential years of life lost by these women, mostly young, black (88%), with unknown levels of schooling (78.2%), single (80%), in District III of the city, and murdered with firearms in their own homes. The specific mortality rate was 10.8 homicides per 100,000 childbearing-age women. The 43.3 years of life lost per woman express the city's characteristics, poverty levels, unemployment, population density, residential instability, and social inequality, exposing residents to social strife, crime, and violence

    BaBar technical design report

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