Article
Study of Υ production in 𝑝Pb collisions at 𝑠𝑁𝑁‾‾‾‾√=8.16 TeV
The production of ϒ(nS) mesons (n = 1, 2, 3) in pPb and Pbp collisions at a centre-of-mass energy per nucleon pair 𝑠NN‾‾‾‾√=8.16sNN=8.16 TeV is measured by the LHCb experiment, using a data sample corresponding to an integrated luminosity of 31.8 nb−1−1. The ϒ(nS) mesons are reconstructed through their decays into two opposite-sign muons. The measurements comprise the differential production cross-sections of the ϒ(1S) and ϒ(2S) states, their forward-to-backward ratios and nuclear modification factors. The measurements are performed as a function of the transverse momentum p𝑇T and rapidity in the nucleon-nucleon centre-of-mass frame y∗∗ of the ϒ(nS) states, in the kinematic range p𝑇T < 25 GeV/c and 1.5 < y∗∗ < 4.0 (−5.0 < y∗∗ < −2.5) for pPb (Pbp) collisions. In addition, production cross-sections for ϒ(3S) are measured integrated over phase space and the production ratios between all three ϒ(nS) states are determined. Suppression for bottomonium in proton-lead collisions is observed, which is particularly visible in the ratios. The results are compared to theoretical models.
Measurements of CP observables in B0 → DK∗0 decays are presented, where D represents a superposition of D0 and 𝐷⎯⎯⎯⎯⎯0D¯0 states. The D meson is reconstructed in the two-body final states K+π−, π+K−, K+K− and π+π−, and, for the first time, in the fourbody final states K+π−π+π−, π+K−π+π− and π+π−π+π−. The analysis uses a sample of neutral B mesons produced in proton-proton collisions, corresponding to an integrated luminosity of 1.0, 2.0 and 1.8 fb−1 collected with the LHCb detector at centre-of-mass energies of 𝑠√=7,8s=7,8 and 13 TeV, respectively. First observations of the decays B0 → D(π+K−)K∗0 and B0 → D(π+π−π+π−)K∗0 are obtained. The measured observables are interpreted in terms of the CP -violating weak phase γ.
Using proton-proton collision data, collected with the LHCb detector and corresponding to 1.0, 2.0 and 1.9 fb−1 of integrated luminosity at the centre-of-mass energies of 7, 8, and 13 TeV, respectively, the decay Λ0b→χc1Λb0→χc1(3872)pK− with χc1(3872) → J/ψ π+π− is observed for the first time. The significance of the observed signal is in excess of seven standard deviations. It is found that (58 ± 15)% of the decays proceed via the two-body intermediate state χc1(3872)Λ(1520). The branching fraction with respect to that of the Λ0bΛb0 → ψ(2S)pK− decay mode, where the ψ(2S) meson is reconstructed in the J/ψ π+π− final state, is measured to be:
𝛽(Λ0b→χc1(3872)pK−)𝛽(Λ0b→ψ(2S)pK−)×𝛽(χc1(3872)→J/ψπ+π−)𝛽(ψ(2S)→J/ψπ+π−)=(5.4±1.1±0.2)×10−2,β(Λb0→χc1(3872)pK−)β(Λb0→ψ(2S)pK−)×β(χc1(3872)→J/ψπ+π−)β(ψ(2S)→J/ψπ+π−)=(5.4±1.1±0.2)×10−2,
where the first uncertainty is statistical and the second is systematic.
The decay-time-dependent 𝐶𝑃CP asymmetry in 𝐵0𝑠→𝐽/𝜓𝐾+𝐾−Bs0→J/ψK+K− decays is measured using proton–proton collision data, corresponding to an integrated luminosity of 1.9fb−11.9fb−1, collected with the LHCb detector at a centre-of-mass energy of 13TeV13TeV in 2015 and 2016. Using a sample of approximately 117 000 signal decays with an invariant 𝐾+𝐾−K+K− mass in the vicinity of the 𝜙(1020)ϕ(1020) resonance, the 𝐶𝑃CP-violating phase 𝜙𝑠ϕs is measured, along with the difference in decay widths of the light and heavy mass eigenstates of the 𝐵0𝑠Bs0-𝐵⎯⎯⎯⎯0𝑠B¯s0 system, ΔΓ𝑠ΔΓs. The difference of the average 𝐵0𝑠Bs0 and 𝐵0B0 meson decay widths, Γ𝑠−Γ𝑑Γs−Γd, is determined using in addition a sample of 𝐵0→𝐽/𝜓𝐾+𝜋−B0→J/ψK+π− decays. The values obtained are 𝜙𝑠=−0.083±0.041±0.006radϕs=−0.083±0.041±0.006rad, ΔΓ𝑠=0.077±0.008±0.003ps−1ΔΓs=0.077±0.008±0.003ps−1 and Γ𝑠−Γ𝑑=−0.0041±0.0024±0.0015ps−1Γs−Γd=−0.0041±0.0024±0.0015ps−1, where the first uncertainty is statistical and the second systematic. These are the most precise single measurements of these quantities to date and are consistent with expectations based on the Standard Model and with a previous LHCb analysis of this decay using data recorded at centre-of-mass energies 7 and 8 TeV. Finally, the results are combined with recent results from 𝐵0𝑠→𝐽/𝜓𝜋+𝜋−Bs0→J/ψπ+π− decays obtained using the same dataset as this analysis, and with previous independent LHCb results.
A model for organizing cargo transportation between two node stations connected by a railway line which contains a certain number of intermediate stations is considered. The movement of cargo is in one direction. Such a situation may occur, for example, if one of the node stations is located in a region which produce raw material for manufacturing industry located in another region, and there is another node station. The organization of freight traffic is performed by means of a number of technologies. These technologies determine the rules for taking on cargo at the initial node station, the rules of interaction between neighboring stations, as well as the rule of distribution of cargo to the final node stations. The process of cargo transportation is followed by the set rule of control. For such a model, one must determine possible modes of cargo transportation and describe their properties. This model is described by a finite-dimensional system of differential equations with nonlocal linear restrictions. The class of the solution satisfying nonlocal linear restrictions is extremely narrow. It results in the need for the “correct” extension of solutions of a system of differential equations to a class of quasi-solutions having the distinctive feature of gaps in a countable number of points. It was possible numerically using the Runge–Kutta method of the fourth order to build these quasi-solutions and determine their rate of growth. Let us note that in the technical plan the main complexity consisted in obtaining quasi-solutions satisfying the nonlocal linear restrictions. Furthermore, we investigated the dependence of quasi-solutions and, in particular, sizes of gaps (jumps) of solutions on a number of parameters of the model characterizing a rule of control, technologies for transportation of cargo and intensity of giving of cargo on a node station.
Event logs collected by modern information and technical systems usually contain enough data for automated process models discovery. A variety of algorithms was developed for process models discovery, conformance checking, log to model alignment, comparison of process models, etc., nevertheless a quick analysis of ad-hoc selected parts of a journal still have not get a full-fledged implementation. This paper describes an ROLAP-based method of multidimensional event logs storage for process mining. The result of the analysis of the journal is visualized as directed graph representing the union of all possible event sequences, ranked by their occurrence probability. Our implementation allows the analyst to discover process models for sublogs defined by ad-hoc selection of criteria and value of occurrence probability
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
The Handbook of CO₂ in Power Systems' objective is to include the state-of-the-art developments that occurred in power systems taking CO₂ emission into account. The book includes power systems operation modeling with CO₂ emissions considerations, CO₂ market mechanism modeling, CO₂ regulation policy modeling, carbon price forecasting, and carbon capture modeling. For each of the subjects, at least one article authored by a world specialist on the specific domain is included.