Fluctuations and Correlations of Conserved Charges in QCD at Finite Temperature with Effective Models

We study fluctuations of conserved charges including baryon number, electric charge, and strangeness as well as the correlations among these conserved charges in the 2+1 flavor Polyakov--Nambu--Jona-Lasinio model at finite temperature. The calculated results are compared with those obtained from recent lattice calculations performed with an improved staggered fermion action at two values of the lattice cutoff with almost physical up and down quark masses and a physical value for the strange quark mass. We find that our calculated results are well consistent with those obtained in lattice calculations except for some quantitative differences for fluctuations related with strange quarks. Our calculations indicate that there is a pronounced cusp in the ratio of the quartic to quadratic fluctuations of baryon number, i.e. $\chi_{4}^{B}/\chi_{2}^{B}$, at the critical temperature during the phase transition, which confirms that $\chi_{4}^{B}/\chi_{2}^{B}$ is a useful probe of the deconfinement and chiral phase transition.Comment: 24 pages, 11 figures; final version published in Phys. Rev.

A Visual Modeling Method for Spatiotemporal and Multidimensional Features in Epidemiological Analysis: Applied COVID-19 Aggregated Datasets

The visual modeling method enables flexible interactions with rich graphical depictions of data and supports the exploration of the complexities of epidemiological analysis. However, most epidemiology visualizations do not support the combined analysis of objective factors that might influence the transmission situation, resulting in a lack of quantitative and qualitative evidence. To address this issue, we have developed a portrait-based visual modeling method called +msRNAer. This method considers the spatiotemporal features of virus transmission patterns and the multidimensional features of objective risk factors in communities, enabling portrait-based exploration and comparison in epidemiological analysis. We applied +msRNAer to aggregate COVID-19-related datasets in New South Wales, Australia, which combined COVID-19 case number trends, geo-information, intervention events, and expert-supervised risk factors extracted from LGA-based censuses. We perfected the +msRNAer workflow with collaborative views and evaluated its feasibility, effectiveness, and usefulness through one user study and three subject-driven case studies. Positive feedback from experts indicates that +msRNAer provides a general understanding of analyzing comprehension that not only compares relationships between cases in time-varying and risk factors through portraits but also supports navigation in fundamental geographical, timeline, and other factor comparisons. By adopting interactions, experts discovered functional and practical implications for potential patterns of long-standing community factors against the vulnerability faced by the pandemic. Experts confirmed that +msRNAer is expected to deliver visual modeling benefits with spatiotemporal and multidimensional features in other epidemiological analysis scenarios

Particle collisions in the lower dimensional rotating black hole space-time with the cosmological constant

In this paper, we study the effect of ultra-high energy collisions of two particles with different energies near the horizon of a 2+1 dimensional BTZ black hole (BSW effect). We find that the particle with the critical angular momentum could exist inside the outer horizon of BTZ black hole regardless of the particle energy. Therefore, for the non-extremal BTZ black hole, the BSW process is possible on the inner horizon with the fine tuning of parameters which are characterized by the motion of particle. While for the extremal BTZ black hole, the particle with the critical angular momentum could only exist on the degenerate horizon, and the BSW process could also happen there.Comment: 12 pages,3 figure

The Acoustic Emission Technique Research on Dynamic Damage Characteristics of the Coal Rock

AbstractThe acoustic emission technique is used to research the deformation and the failure process, investigate the deformation and injury regularity, discuss the physical process of acoustic emission of the coal and gas outburst and reveal the evolution process and disaster mechanism of the coal rock dynamic disaster. In this paper, the relationship between the damage and the acoustic emission is researched to get the coal cock damage expression which is expressed by the acoustic emission cumulative value. Meanwhile, the quasi-static is used to analyze the evolution process of the coal rock's inner damage and describe the coal rock's single axis damage character. On the base of the coal rock unit damage model, the constitutive relationship of acoustic emission coal rock is studied, which is the theory analysis for the coal and gas outburst. It is very significant for the research of the coal and gas outburst mechanism and prediction