Particle acceleration in the vacuum gaps in black hole magnetospheres

We consider particle acceleration in vacuum gaps in magnetospheres of black holes powered through Blandford-Znajek mechanism and embedded into radiatively-inefficient accretion flow (RIAF) environment. In such situation the gap height is limited by the onset of gamma-gamma pair production on the infrared photons originating from the RIAF. We numerically calculate acceleration and propagation of charged particles taking into account the detailed structure of electric and magnetic field in the gap and in the entire black hole magnetosphere, radiative energy losses and interactions of gamma rays produced by the propagated charged particles with the background radiation field of RIAF. We show that the presence of the vacuum gap has clear observational signatures. The spectra of emission from gaps embedded into a relatively high luminosity RIAF are dominated by the inverse Compton emission with a sharp, super-exponential cut-off in the very-high-energy gamma-ray band. The cut-off energy is determined by the properties of the RIAF and is largely independent of the structure of magnetosphere and geometry of the gap.The spectra of the gap residing in low-luminosity RIAFs are dominated by synchrotron / curvature emission with the spectra extending into 1-100 GeV energy range. We also consider the effect of possible acceleration of protons in the gap and find that proton energies could reach the ultra-high-energy cosmic ray (UHECR) range only in extremely low luminosity RIAFs.Comment: 10 pages, 15 figure

Physical conditions in potential sources of ultra-high-energy cosmic rays: Updated Hillas plot and radiation-loss constraints

We review basic constraints on the acceleration of ultra-high-energy (UHE) cosmic rays (CRs) in astrophysical sources, namely the geometrical (Hillas) criterion and restrictions from radiation losses in different acceleration regimes. Using the latest available astrophysical data, we redraw the Hillas plot and figure out potential UHECR accelerators. For the acceleration in central engines of active galactic nuclei, we constrain the maximal UHECR energy for a given black-hole mass. Among active galaxies, only the most powerful ones, radio galaxies and blazars, are able to accelerate protons to UHE, though acceleration of heavier nuclei is possible in much more abundant lower-power Seyfert galaxies.Comment: 27 pages, 12 figures. V.2: numerous minor changes, results untouched. Accepted in Physics Uspekhi (UFN)

A discrete model of guided modes and anomalous scattering in periodic structures

We study a discrete prototype of anomalous scattering associated with the interaction of guided modes of a periodic scatterer and plane waves incident upon the scatterer. The transmission anomalies arise because of the non-robustness of a guided mode, a mode that exists only at a specific frequency and wave number pair. The simplicity of the discrete prototype allows one to make certain explicit calculations and proofs, and to examine details of important resonant phenomena of the open wave guides. The main results are (1) a formula for transmission anomalies near a non-robust guided mode with rigorous error estimates that extends the formula of Shipman and Venakides [28] to non-zero Bloch wave number and (2) rigorous analysis of a bifurcation that connects the anomaly for non-zero wave number to that of zero wave number

Fund assessment tools final certification of masters for the educational program «Communication Technologies»

Presented by the fund valuation means the final certification of students to graduate educational program «Communication Technologies». Identified the key components o f the fund evaluation tools. The content of the key components. We describe the criteria for assessment of final qualifying works of studentsПредставлено назначение фонда оценочных средств итоговой аттестации студентов для образовательной программы магистратуры «Коммуникационные технологии». Определены ключевые компоненты фонда оценочных средств. Раскрыто содержание ключевых компонент. Описаны критерии оценивания выпускных квалификационных работ студенто

Towards a model of population of astrophysical sources of ultra-high-energy cosmic rays

We construct and discuss a toy model of the population of numerous non-identical extragalactic sources of ultra-high-energy cosmic rays. In the model, cosmic-ray particles are accelerated in magnetospheres of supermassive black holes in galactic nuclei, the key parameter of acceleration being the black-hole mass. We use astrophysical data on the redshift-dependent black-hole mass function to describe the population of these cosmic-ray accelerators, from weak to powerful, and confront the model with cosmic-ray data.Comment: 9 pages, 4 figures, Revtex 4.

Preparation of masters of technology research and educational environments

Presenting the program of the discipline «Technology research and educational environments». The groups of students competencies. Disclosed competence of each group. We describe the knowledge, skills and abilities of studentsПредставлена программа дисциплины «Технологии научно-образовательных сред». Определены группы компетенций студентов. Раскрыты компетенции каждой группы. Описаны знания, навыки и умения обучающихс

New segment methodology and service design intelligent information agent for large-scale networks

Presented by expanding design methodology intelligent software agents for large-scale networksПредставлено расширение методологии проектирования интеллектуальных программных агентов для крупномасштабных сете

Expansion of knowledge about information protection in educational programs of mast

Presents the conditions for the development of the digital economy, considered the objective prerequisites for the expansion of knowledge about information security in graduate education programs, describes the techniques for studying the dynamic characteristics of quantum means of cryptographic protection, proposed ways of end-to-end connectivity of quantum technologies and information security technologiesПредставлены условия для развития цифровой экономики, рассмотрены объективные предпосылки для расширения знаний о защите информации в образовательных программах магистратуры, описаны приёмы исследования динамических характеристик квантовых средств криптозащиты, предложены способы сквозной связности квантовых технологий и технологий информационной безопасност