2,369 research outputs found
Recent results on single vector boson plus jets production at CMS
No full textThe most recent results on the hadroproduction of an electroweak boson in association with one or more jets within the CMS experiment are presented. The cross section is studied differentially with respect to the transverse momentum and the angular correlation of the final state particles. Attention is given to the associated production of a vector boson plus flavour-tagged (b, c) jets. Comparison between data and different state-of-the-art theoretical predictions including (nextto)-leading-order corrections are presented as well
Eco-programming of industrial robots for sustainable manufacturing via dynamic time scaling of trajectories
No full textNowadays, Industrial Robots (IRs) have become widespread in many manufacturing industries. Medium and high payload IRs cover a significant percentage of the overall factory Energy Consumption (EC). This article focuses on the IRs eco-programming to minimize the EC of a robot, being energy efficiency one of the fundamental aims of sustainable manufacturing. By leveraging well-known trajectory scaling methods, this research develops a novel, versatile, fast, and efficient process to define the IR optimal velocity/acceleration profile in time, keeping the geometry of the trajectory fixed. A complete IR system model that founds application in various types of 6 degrees of freedom articulated manipulators has been developed by considering electrical motors, actuator drive systems, and controller cabinet losses. A new optimization technique based on Dynamic Time Scaling of trajectories is presented, and the obtained results are compared with other methods used in the scientific literature. When performing critical path analysis, the EC of the robot system is estimated to be cut down, being the robot motion time fixed, by about 13% through this novel approach. The model has been validated through commercial software, and the proposed optimization algorithm has been implemented in a user-friendly interface tool
Measurement of the dependence of the hadron production fraction ratios f_s / f_u and f_d / f_u on B meson kinematic variables in proton-proton collisions at sqrt{s) = 13 TeV
No full textThe dependence of the ratio between the B 0
s and B þ hadron production fractions, f s =f u , on the
transverse momentum (p T ) and rapidity of the B mesons is studied using the decay channels B 0
s → J=ψφ
and B þ → J=ψK þ . The analysis uses a data sample of proton-proton collisions at a center-of-mass energy
of 13 TeV, collected by the CMS experiment in 2018 and corresponding to an integrated luminosity of
61.6 fb −1 . The f s =f u ratio is observed to depend on the B pT and to be consistent with becoming
asymptotically constant at large p T . No rapidity dependence is observed. The ratio of the B 0 to B þ meson
production fractions, f d =f u , is also measured, for the first time in proton-proton collisions, using the
B 0 → J=ψK "0 decay channel. The result is found to be within 1 standard deviation of unity and
independent of p T and rapidity, as expected from isospin invarianc
TRASFERIMENTO DI ACQUA DOLCE E DI INQUINANTI NELLA LAGUNA DI VENEZIA
No full textIl lavoro tratta i flussi di massa di acqua dolce ed il trasporto di inquinanti attraverso la laguna di Venezia verso il mare Adriatico
Inclusive and differential cross section measurements of single top quark production in association with a Z boson in proton-proton collisions at sqrt(s) = 13 TeV
No full textInclusive and differential cross sections of single top quark production in association with a Z boson are measured in proton-proton collisions at a center-of-mass energy of 13 TeV with a data sample corresponding to an integrated luminosity of 138 fb(-1) recorded by the CMS experiment. Events are selected based on the presence of three leptons, electrons or muons, associated with leptonic Z boson and top quark decays. The measurement yields an inclusive cross section of 87.9(-7.3)(+7.5) (stat)(-6.0)(+7.3)(syst) fb for a dilepton invariant mass greater than 30 GeV, in agreement with standard model (SM) calculations and represents the most precise determination to date. The ratio between the cross sections for the top quark and the top antiquark production in association with a Z boson is measured as 2.37(-0.42)(+0.56)(stat)(-0.13)(+0.27) (syst). Differential measurements at parton and particle levels are performed for the first time. Several kinematic observables are considered to study the modeling of the process. Results are compared to theoretical predictions with different assumptions on the source of the initial-state b quark and found to be in agreement, within the uncertainties. Additionally, the spin asymmetry, which is sensitive to the top quark polarization, is determined from the differential distribution of the polarization angle at parton level to be 0.54 +/- 0.16 (stat)+/- 0.06 (syst), in agreement with SM predictions
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