Effects of dense quark matter on gluon propagators in lattice QC2D

The transverse and longitudinal gluon propagators in the Landau gauge are studied in the two-color lattice QCD at nonzero quark chemical potential μq. Parametrization of the momentum dependence of the propagators is provided for all values of chemical potential under study. We find that the longitudinal propagator is infrared suppressed at nonzero μq with suppression increasing with increasing μq. The transverse propagator dependence on μq was found to be opposite: it is enhanced at large μq. It is found, respectively, that the electric screening mass is increasing while the magnetic screening mass is decreasing with increasing μq. Nice agreement between the electric screening mass computed from the longitudinal propagator and the Debye mass computed earlier from the singlet static quark-antiquark potential was found. We discuss how the dependence of the propagators on the chemical potential correlates with the respective dependence of the string tension. Additionally, we consider the difference between two propagators as a function of the momentum and make interesting observations

Lattice study of the electromagnetic conductivity of the quark-gluon plasma in an external magnetic field

We study the electromagnetic conductivity of QGP in a magnetic background by lattice simulations with Nf=2+1 dynamical rooted 2-stout smeared staggered fermions at the physical point. We study the correlation functions of the electromagnetic currents at T=200, 250 MeV and use the Tikhonov approach to extract the conductivity. The conductivity is found to rise with the magnetic field in the parallel direction and to decrease in the transverse direction, giving evidence for both the chiral magnetic effect and the magnetoresistance phenomenon in QGP. We also estimate the chiral charge relaxation time in QGP

Gluon Propagators in QC2D at High Baryon Density

We study the transverse and longitudinal gluon propagators in the Landau-gauge lattice QCD with gauge group SU(2) at nonzero quark chemical potential and zero temperature. We show that both propagators demonstrate substantial dependence on the quark chemical potential. This observation does not agree with earlier findings by other groups

Electrical conductivity of the quark-gluon plasma: perspective from lattice QCD

A discussion on the electrical conductivity of the quark-gluon plasma as determined by lattice QCD is given. After a reminder of basic definitions and expectations, various methods for spectral reconstruction are reviewed, including the use of Ans\"atze and sum rules, the Maximum Entropy and Backus-Gilbert methods, and Tikhonov regularisation. A comprehensive overview of lattice QCD results obtained so far is given, including a comparison of the different lattice formulations. A noticeable consistency for the conductivities obtained is seen, in spite of the differences in the lattice setups and spectral reconstruction methods. It is found that in the case of quenched QCD little temperature dependence of $\sigma/T$ is seen in the temperature range investigated, while for QCD with dynamical quarks a reduction of $\sigma/T$ in the vicinity of the thermal crossover is observed, compared to its value in the QGP. Several open questions are posed at the end.Comment: 13 pages, 3 figures, invited contribution to the EPJA topical issue "Theory of hot matter and relativistic heavy-ion collisions (THOR)

ADMINISTRATIVE LEGAL REGULATION PRINCIPLES OF RESTRICTIONS ON HUMAN RIGHTS AND FREEDOMS OF CITIZENS

Abstract. This article covered some issues regarding the principles of administrative and legal regulation ofrestrictions on the rights and freedoms of a person and citizen in the Russian Federation and at the international level. The authors presented the definition of these principles and their system. Here, the main international acts, the Constitution and current legislation of the Russian Federation are analyzed, and the system of principles for legal consolidation and regulation of restrictions on human rights and freedoms is fixed. According to the research findings, conclusions were made on the role of legal principles in the administrative and legal regulation of legal restrictions.Keywords: legal restrictions, restriction of rights and freedoms of man and citizen, legality, proportionality

ADMINISTRATIVE LEGAL REGULATION PRINCIPLES OF RESTRICTIONS ON HUMAN RIGHTS AND FREEDOMS OF CITIZENS

Abstract.This article covered some issues regarding the principles of administrative and legal regulation ofrestrictions on the rights and freedoms of a person and citizen in the Russian Federation and at the international level. The authors presented the definition of these principles and their system. Here, the main international acts, the Constitution and current legislation of the Russian Federation are analyzed, and the system of principles for legal consolidation and regulation of restrictions on human rights and freedoms is fixed. According to the research findings, conclusions were made on the role of legal principles in the administrative and legal regulation of legal restrictions.Keywords: legal restrictions, restriction of rights and freedoms of man and citizen, legality, proportionality

About the productivity of shaft air heater located along the perimeter of pithead

In the existing shaft air heaters that heat the air for air suppliers in the cold season heater channel is used. Part of the air from heater goes to the channel, another one is sucked through pithead by general shaft pressure drawdown formed by main ventilation installation. Wherein, mix of two air flow leads to shaft heat regime violation that could break the pressurization of intertubular sealers. Moreover, heater channel design is associated with additional expenditures. Paper describes the air heater, located in the pithead. The location of a heater in one line along pithead perimeter is the key feature. In this case there is no need to design heater channel, thus, there is no problem with mix of cold and heated air flows. Air processing it the heater located on the perimeter of pithead and mix of cold and heated air flows in the supplier from the channel was modeled in the software Soldworks flow simulation. The comparative analysis of both types of heater proved efficiency of proposed design of installation, smooth propagation of heat field along the all cross-section of air supplier, decrease of consumption of electric power for air processing and installation operation by transformation negative natural common excavation traction to positive

Application of the cybernetic approach to price-dependent demand response for underground mining enterprise electricity consumption

The article considers a cybernetic model for the price-dependent demand response (DR) consumed by an underground mining enterprise (UGME), in particular, the main fan unit (MFU). A scheme of the model for managing the energy consumption of a MFU in the DR mode and the implementation of the cybernetic approach to the DR based on the IoT platform are proposed. The main functional requirements and the algorithm of the platform operation are described, the interaction of the platform with the UGME digital model simulator, on which the processes associated with the implementation of the technological process of ventilation and electricity demand response will be simulated in advance, is shown. The results of modeling the reduction in the load on the MFU of a mining enterprise for the day ahead are given. The presented solution makes it possible to determine in advance the necessary power consumption for the operation of the main power supply unit, manage its operation in an energy-saving mode and take into account the predicted changes in the planned one (e.g., when men hoisting along an air shaft) and unscheduled (e.g., when changing outdoor air parameters) modes. The results of the study can be used to reduce the cost of UGME without compromising the safety of technological processes, both through the implementation of energy-saving technical, technological or other measures, and with the participation of enterprises in the DR market. The proposed model ensures a guaranteed receipt of financial compensation for the UGME due to a reasonable change in the power consumption profile of the MFU during the hours of high demand for electricity, set by the system operator of the Unified Energy System