Two-particle correlations with Formula omitted, Formula omitted/ Formula omitted, and charged hadrons as trigger particles in the transverse momentum range Formula omitted GeV/ Formula omitted, and ...associated charged particles within Formula omitted GeV/ Formula omitted, are studied at midrapidity in pp and central Pb-Pb collisions at a centre-of-mass energy per nucleon-nucleon collision Formula omitted TeV with the ALICE detector at the LHC. After subtracting the contributions of the flow background, the per-trigger yields are extracted on both the near and away sides, and the ratio in Pb-Pb collisions with respect to pp collisions ( Formula omitted) is computed. The per-trigger yield in Pb-Pb collisions on the away side is strongly suppressed to the level of Formula omitted Formula omitted for Formula omitted GeV/ Formula omitted as expected from strong in-medium energy loss, while an enhancement develops at low Formula omitted on both the near and away sides, reaching Formula omitted Formula omitted and 2.7 respectively. These findings are in good agreement with previous ALICE measurements from two-particle correlations triggered by neutral pions ( Formula omitted-h) and charged hadrons (h-h) in Pb-Pb collisions at Formula omitted TeV. Moreover, the correlations with Formula omitted mesons and Formula omitted/ Formula omitted baryons as trigger particles are compared to those of inclusive charged hadrons. The results are compared with the predictions of Monte Carlo models.
The uniformity and consistency of X-ray mirror film materials prepared by experimental methods are difficult to guarantee completely. These factors directly affect the service life of free electron ...laser devices in addition to its own optical properties. Therefore, the quality of the film material, especially the density, has a critical effect on its application. Boron carbide film and monocrystalline silicon substrate were suitable examples to explore their influence of density on the damage threshold based on Monte Carlo and heat-conduction methods. Through simulation results, it was found that the change in film density could affect the energy deposition depth and damage threshold. When the film density was 2.48 g/cmsup.3, it had relatively high damage threshold in all energy ranges. And then the specific incident parameter for practical application was investigated. It was found that the damage mechanism of the Bsub.4C/Si was the melting of the interface. And the damage threshold was also higher with the film density of 2.48 g/cmsup.3. Therefore, it was recommended to maintain the density at this value as far as possible when preparing the film, and to ensure the uniformity and consistency of the film material.
We investigated (using Monte-Carlo and first-principle calculations) the effect of pressure on the phase diagrams and elastic properties of Ti.sub.xCo.sub.1-x (a superalloy candidate). USPEX ...(Universal Structure Predictor: Evolutionary Xtallography) generated the parent structures required by the Monte-Carlo calculation of the phase diagrams at different pressures (0-100 GPa). The calculated space groups and formation energies qualitatively conform with the experiment within the Co-rich region at 0 GPa. We observed pressure-induced structural transition from the cubic to the tetragonal phase around 80 GPa, comparable with the reported 66 GPa transition pressure. Widening of the phases' miscibility gaps with the pressure was regarded as an indication for the increase of the melting points. Interestingly, the dependence of the calculated chemical potential on pressure and temperature was consistent with the thermodynamic activity for the binary solid mixture. Finally, enhancement of the elastic properties of the parent structures was observed with increasing pressure. Graphical abstract
The production of Formula omitted, Formula omitted, Formula omitted, Formula omitted, Formula omitted, Formula omitted, Formula omitted, Formula omitted, Formula omitted, and their antiparticles was ...measured in inelastic proton-proton (pp) collisions at a center-of-mass energy of Formula omitted = 13 TeV at midrapidity ( Formula omitted) as a function of transverse momentum ( Formula omitted) using the ALICE detector at the CERN LHC. Furthermore, the single-particle Formula omitted distributions of Formula omitted, Formula omitted, and Formula omitted in inelastic pp collisions at Formula omitted TeV are reported here for the first time. The Formula omitted distributions are studied at midrapidity within the transverse momentum range Formula omitted GeV/c, depending on the particle species. The Formula omitted spectra, integrated yields, and particle yield ratios are discussed as a function of collision energy and compared with measurements at lower Formula omitted and with results from various general-purpose QCD-inspired Monte Carlo models. A hardening of the spectra at high Formula omitted with increasing collision energy is observed, which is similar for all particle species under study. The transverse mass and Formula omitted scaling properties of hadron production are also studied. As the collision energy increases from Formula omitted = 7-13 TeV, the yields of non- and single-strange hadrons normalized to the pion yields remain approximately constant as a function of Formula omitted, while ratios for multi-strange hadrons indicate enhancements. The Formula omitted-differential cross sections of Formula omitted, Formula omitted and Formula omitted ( Formula omitted) are compared with next-to-leading order perturbative QCD calculations, which are found to overestimate the cross sections for Formula omitted and Formula omitted ( Formula omitted) at high Formula omitted.
The evaluation of water-alternating-gas (WAG) efficiency and profitability is complicated by a large number of reservoir, operating, and economic parameters and constraints. This study aims at ...understanding the influence of the oil composition on different WAG injections. By employing compositional reservoir modeling and the Monte Carlo method to characterize the diversity of oils occurring in nature, we simulate the microscopic displacement efficiency of COsub.2 flooding when it is applied to both light- and heavy-oil reservoirs. We find that the economic performance of WAG in both miscible and immiscible scenarios is mainly characterized by the dimensionless injection rate and the oil density at surface conditions. Neither the bubble point pressure nor the minimum miscibility pressure can be used for the quantification of the optimal WAG parameters. We present our estimates of the best strategies for the miscible and immiscible injections and verify some of our previous results for randomly sampled oils. In particular, we demonstrate that COsub.2 flooding is better to apply at higher-dimensionless injection rates. We show that the injection of COsub.2 organized at a light-oil reservoir results in a higher profitability of WAG, although this comes at the cost of lower carbon storage efficiency.
Heterogeneities in contact networks have a major effect in determining whether a pathogen can become epidemic or persist at endemic levels. Epidemic models that determine which interventions can ...successfully prevent an outbreak need to account for social structure and mixing patterns. Contact patterns vary across age and locations (e.g. home, work, and school), and including them as predictors in transmission dynamic models of pathogens that spread socially will improve the models' realism. Data from population-based contact diaries in eight European countries from the POLYMOD study were projected to 144 other countries using a Bayesian hierarchical model that estimated the proclivity of age-and-location-specific contact patterns for the countries, using Markov chain Monte Carlo simulation. Household level data from the Demographic and Health Surveys for nine lower-income countries and socio-demographic factors from several on-line databases for 152 countries were used to quantify similarity of countries to estimate contact patterns in the home, work, school and other locations for countries for which no contact data are available, accounting for demographic structure, household structure where known, and a variety of metrics including workforce participation and school enrolment. Contacts are highly assortative with age across all countries considered, but pronounced regional differences in the age-specific contacts at home were noticeable, with more inter-generational contacts in Asian countries than in other settings. Moreover, there were variations in contact patterns by location, with work-place contacts being least assortative. These variations led to differences in the effect of social distancing measures in an age structured epidemic model. Contacts have an important role in transmission dynamic models that use contact rates to characterize the spread of contact-transmissible diseases. This study provides estimates of mixing patterns for societies for which contact data such as POLYMOD are not yet available.
Although the phenomenon of collective order formation by cell–cell interactions in motile cells, microswimmers, has been a topic of interest, most studies have been conducted under conditions of high ...cell density, where the space occupancy of a cell population relative to the space size ϕ>0.1 (ϕ is the area fraction). We experimentally determined the spatial distribution (SD) of the flagellated unicellular green alga Chlamydomonas reinhardtii at a low cell density (ϕ≈0.01) in a quasi-two-dimensional (thickness equal to cell diameter) restricted space and used the variance-to-mean ratio to investigate the deviation from the random distribution of cells, that is, do cells tend to cluster together or avoid each other? The experimental SD is consistent with that obtained by Monte Carlo simulation, in which only the excluded volume effect (EV effect) due to the finite size of cells is taken into account, indicating that there is no interaction between cells other than the EV effect at a low cell density of ϕ≈0.01. A simple method for fabricating a quasi-two-dimensional space using shim rings was also proposed.
By using exact quantum Monte Carlo methods we calculate the ground-state properties of the liquid phase in one-dimensional Bose mixtures with contact interactions. We find that the liquid state can ...be formed if the ratio of coupling strengths between interspecies attractive and intraspecies repulsive interactions exceeds a critical value. As a function of this ratio we determine the density where the energy per particle has a minimum and the one where the compressibility diverges, thereby identifying the equilibrium density and the spinodal point in the phase diagram of the homogeneous liquid. Furthermore, in the stable liquid state, we calculate the chemical potential, the speed of sound, as well as structural and coherence properties, such as the pair correlation function, the static structure factor, and the one-body density matrix, thus providing a detailed description of the bulk region in self-bound droplets.
![The Influence of B[sub.4]C ...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/1996-1944/small "The Influence of B[sub.4]C Film Density on Damage Threshold Based on Monte Carlo Method for X-ray Mirror")
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