Search results for "production [vector meson]"
showing 10 items of 311 documents
Measurement of the chi(b) (3 P) mass and of the relative rate of chi(b1) (1 P) and chi(b2) (1 P) production
2014
The production of $\chi_b$ mesons in proton-proton collisions is studied using a data sample collected by the LHCb detector, at centre-of-mass energies of $\sqrt{s}=7$ and $8$ TeV and corresponding to an integrated luminosity of 3.0 fb$^{-1}$. The $\chi_b$ mesons are identified through their decays to $\Upsilon(1S)\gamma$ and $\Upsilon(2S)\gamma$ using photons that converted to $e^+e^-$ pairs in the detector. The $\chi_b(3P)$ meson mass, and the relative prompt production rate of $\chi_{b1}(1P)$ and $\chi_{b2}(1P)$ mesons as a function of the $\Upsilon(1S)$ transverse momentum in the $\chi_b$ rapidity range 2.0< $y$<4.5, are measured. Assuming a mass splitting between the $\chi_{b1}(3P)$ an…
The rate of photon production in the quark-gluon plasma from lattice QCD
2020
We calculate the thermal rate of real-photon production in the quark-gluon plasma at a temperature of $T=254$ MeV using lattice QCD. The calculation is based on the difference between the spatially transverse and longitudinal parts of the polarization tensor, which has the advantage of falling off rapidly at large frequencies. We obtain this linear combination in the time-momentum representation from lattice QCD with two flavors of quarks in the continuum limit with a precision of about two parts per mille. Applying a theoretically motivated fit ansatz for the associated spectral function, we obtain values for the photon rate that are in line with QCD weak-coupling calculations; for photon …
PRODUCTION-RATE AND DECAY LIFETIME MEASUREMENTS OF B(S)0 MESONS AT LEP USING D(S) AND PHI MESONS
1994
The study of the properties of inclusive production of Ds mesons and of events in which a φ{symbol} and a muon are present in the same jet provides two independent measurements of the probability, fs w, for a heavy quark to hadronize into a strange B or D meson. The data sample analysed corresponds to 243,000 hadronic Z0 decays. The combined value of these measurements is fs w=0.19±0.06±0.08. From the flight distance distributions of Ds and of (φ{symbol}-lepton) secondary vertices, with the lepton emitted at high transverse momentum relative to the jet axis, two values are obtained for the Bs 0 meson lifetime. Combining these measurements with a previous result based on the study of Ds-μ ev…
Search for the Associated Production of the Standard-Model Higgs Boson in the All-Hadronic Channel
2009
We report on a search for the standard-model Higgs boson in pp collisions at s=1.96 TeV using an integrated luminosity of 2.0 fb(-1). We look for production of the Higgs boson decaying to a pair of bottom quarks in association with a vector boson V (W or Z) decaying to quarks, resulting in a four-jet final state. Two of the jets are required to have secondary vertices consistent with B-hadron decays. We set the first 95% confidence level upper limit on the VH production cross section with V(-> qq/qq('))H(-> bb) decay for Higgs boson masses of 100-150 GeV/c(2) using data from run II at the Fermilab Tevatron. For m(H)=120 GeV/c(2), we exclude cross sections larger than 38 times the standard-m…
Statistical performance of a multiclass bulk production queueing system
2004
Abstract In this paper, we discuss how to statistically analyze a make-to-stock production system the behaviour of which depends on a multiclass bulk queueing system. The performance of the system is evaluated in terms of the different demands of products, processing times and, mainly, through the finished product inventory and other related measures that quantify the queueing effects in the system. A numerical example which illustrates the applicability of the results in an inventory scenario is also discussed.
Capital humain et compétences de base des adultes : production et valorisation
2013
Basic skills are important in current policies because of high costs generated by illiteracy and supported by the society. The aim of the present thesis is to bring a new contribution on this thematic in a microeconomic approach. It consists of two parts. The first one concerns the valorization of basic skills on the labor market, through chapters 1 and 2, while the second one concerns the production of French skills according to the migratory origins, through chapters 3 and 4. Chapter 1 is about the returns to basic skills on the labor market, in terms of overeducation/undereducation and in terms of wages. The central hypothesis is to assume that education, through the diploma, is not a go…
Comparison of problem solving tools in lean organizations
2017
As global market competition is getting fiercer, and companies are looking at ways to stay on top, more and more organizations are looking at Lean Manufacturing and lean tools to support them in achieving their goals. Especially within the automotive industry, lean practices are very well received. The speed at which the automotive industry is evolving, especially but not only, in countries like Romania, leads to the need to carefully analyze lean manufacturing concepts, examine them against local production conditions, and to develop and standardize them. One of the most important things to take into consideration here is the application of an adequate problem solving technique to avoid wa…
Recent Developments in Heterogeneous Photoreactor Modelling
1991
A selection of recently proposed heterogeneous photoreactors is presented. In some cases efforts have been made for the formulation of models able to describe the photoreactor behaviour with regard to the absorption of radiation. Examples of proposals of both novel photoreactor and models are critically reviewed.
Education, intériorisation de la méritocratie et perception des frontières entre groupes sociaux
2006
La présente recherche (qui s'achèvera en 2007-2008) envisage une manière de tester empiriquement la thèse de la reproduction de Bourdieu et Passeron en explorant la perception de la légitimité des inégalités scolaires et de leurs incidences sociales, chez des individus inégalement formés. Elle entend ainsi explorer les relations entre trajectoire scolaire (niveau atteint, mais aussi filière de formation suivie) et intériorisation de la méritocratie et plus largement le jugement sur les inégalités existantes.