Measurement of the semileptonic charge asymmetry in B0 meson mixing with the D0 detector

We present a measurement of the semileptonic mixing asymmetry for B0 mesons, asld, using two independent decay channels: B0→μ +D -X, with D -→K +π -π -; and B0→μ +D *-X, with D * -→D ̄0π -, D ̄0→ K +π - (and charge conjugate processes). We use a data sample corresponding to 10.4fb -1 of pp̄ collisions at √s=1.96TeV, collected with the D0 experiment at the Fermilab Tevatron collider. We extract the charge asymmetries in these two channels as a function of the visible proper decay length of the B0 meson, correct for detector-related asymmetries using data-driven methods, and account for dilution from charge-symmetric processes using Monte Carlo simulation. The final measurement combines four signal visible proper decay length regions for each channel, yielding asld=[0.68±0.45(stat)±0.14(syst)]%. This is the single most precise measurement of this parameter, with uncertainties smaller than the current world average of B factory measurements. © 2012 American Physical Society.

Combination of the top-quark mass measurements from the Tevatron collider

The top quark is the heaviest known elementary particle, with a mass about 40 times larger than the mass of its isospin partner, the bottom quark. It decays almost 100% of the time to a W boson and a bottom quark. Using top-antitop pairs at the Tevatron proton-antiproton collider, the CDF and D0 Collaborations have measured the top quark's mass in different final states for integrated luminosities of up to 5.8fb -1. This paper reports on a combination of these measurements that results in a more precise value of the mass than any individual decay channel can provide. It describes the treatment of the systematic uncertainties and their correlations. The mass value determined is 173.18±0.56(stat)±0.75(syst)GeV or 173.18±0.94GeV, which has a precision of ±0.54%, making this the most precise determination of the top-quark mass. © 2012 American Physical Society.

Measurement of angular correlations of jets at s=1.96 TeV and determination of the strong coupling at high momentum transfers

We present a measurement of the average value of a new observable at hadron colliders that is sensitive to QCD dynamics and to the strong coupling constant, while being only weakly sensitive to parton distribution functions. The observable measures the angular correlations of jets and is defined as the number of neighboring jets above a given transverse momentum threshold which accompany a given jet within a given distance δR in the plane of rapidity and azimuthal angle. The ensemble average over all jets in an inclusive jet sample is measured and the results are presented as a function of transverse momentum of the inclusive jets, in different regions of δR and for different transverse momentum requirements for the neighboring jets. The measurement is based on a data set corresponding to an integrated luminosity of 0.7 fb -1 collected with the D0 detector at the Fermilab Tevatron Collider in pp- collisions at s=1.96 TeV. The results are well described by a perturbative QCD calculation in next-to-leading order in the strong coupling constant, corrected for non-perturbative effects. From these results, we extract the strong coupling and test the QCD predictions for its running over a range of momentum transfers of 50-400 GeV. © 2012 Elsevier B.V.

Study of the decay Bs0→J/ψf2′(1525) in μ +μ -K +K - final states

We investigate the decay Bs0→J/ψK +K - for invariant masses of the K +K - pair in the range 1.35

Tambores da missão: a conservação como instrumento de preservação da memória afro-brasileira

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

O esquema de ação e a constituição do sujeito epistêmico: contribuições da epistemologia genética à teoria do conhecimento

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Measurement of the p(p)over-bar -> W plus b plus X production cross section at root s=1.96 TeV D0 Collaboration

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Measurement of the combined rapidity and p(T) dependence of dijet azimuthal decorrelations in p(p)over-bar collisions at root s=1.96 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

A genetic linkage study in Brazil identifies a new locus for persistent developmental stuttering on chromosome 10

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

O Mal-estar no Trabalho: a culpa como mal-estar e a culpa do mal-estar

The present work is a reflexive-theoretically research that intends, by the light of Psychoanalytic and Freudo-Marxim theories, to think about the work malaise - effect of a repressive civilization -, and the sublimation possibilities, in the context of the discussions about the conflict individual-civilization. The work favors the essential thing for the human race's representations. Current researches indicate the importance of thinking the work in the process physical and mental health/illness, as well as the subjectivity of the human race in the present time. However, the organizations of work, using reductionist views, with the psychiatric-medical Knowledge/power as accomplice, have a tendency to disregard their responsibilities in the "production" of the illnesses in the workers. Freud, by the neurosis's understanding, showed that in the individual-civilization conflict the first one pays a high price: the constant malaise (the guilt as malaise). While who detains the guilt, in the social sense of the word (the guilt of malaise), is the human culture, intermediated by the organizations, defenders of the minority's interests that hold the manners of production/exploration. According to Freud, the growth of the feeling of guilt is inevitable, considering the necessity of the drives repression to cultural progress through displeasure work. However, Reich and Marcuse theorize an exit for the Freudian pessimism about the conflict between the individual and the civilization. Freud didn't consider properly the nature socio-historical of the Reality Principle, understanding it like universal. Therefore, the level of repression would have a specific socio-economic class: surplus value for a minority and more repression for the great mass. A less repressive Reality Principle might provide a fair progress of the humanity. It's in the list of discussion the possibility of the work in social and psychological conditions that allow the reduction of worker's malaise in the civilization's breast.