About the influence of asymmetry of nuclear matter on the unitarity of singlet-triplet superfluid states

Unitarity of superfluid states in nuclear matter is studied in the case that the quasi-particle energy matrix holds scalar and vector components in isospin space at the same time, ξ = ξ0 + ξτ. The vector component of ξ can be generated by the asymmetry of nuclear matter (different concentrations of neutrons and protons). It is shown that in considered case the superfluid states become non-unitary. The work is done using the Fermi liquid approach [2].Рассмотрена возможность существования унитарных сверхтекучих состояний в ядерной материи в случае, когда в матрице энергии квазичастицы присутствуют одновременно как скалярные, так и векторные компоненты, ξ = ξ0 + ξτ. Векторный компонент ξ может появиться благодаря асимметрии ядерной материи (различным концентрациям составляющих ее нейтронов и протонов). Показано, что в рассмотренном случае сверхтекучие состояния становятся неунитарными. Работа выполнена на основе фермижидкостного подхода [2].Розглянуто можливість існування унітарних надплинних станів у ядерній матерії у випадку, коли в матриці енергії квазічастинки присутні як скалярні, так і векторні компоненти водночас, ξ = ξ0 + ξτ, причому векторний компонент ξ може з'явитися завдяки асиметрії ядерної матерії (різним концентраціям нейтронів та протонів, з яких вона складається). Показано, що у розглянутому випадку надплинні стани стають неунітарними. Роботу виконано на основі фермірідинного підходу [2]

Transient Electromagnetic Wave Scattering from Dispersive Anisotropic Layered Medium

Transient electromagnetic (EM) wave scattering from a stratified anisotropic medium with temporal and spatial dispersion is considered. The dispersive anisotropic medium is modeled by constitutive relations that involve four second rank tensor susceptibilities, containing time convolution integrals. Scalarization approach to the solution of transient EM scattering problems in layered anisotropic medium is outlined. As a practical application the physical model of the effective absorber was proposed and numerically investigated.В работе исследуется нестационарное рассеяние электромагнитных волн в анизотропной слоистой среде с пространственной и временной дисперсией. Анизотропная среда описывается материальными уравнениями типа временной свертки с ядрами восприимчивости, представляющими собой тензоры второго ранга. Предложена и численно исследована модель широкополосного поглощающего покрытия.У роботі досліджується нестаціонарне розсіяння електромагнітних хвиль в анізотропному шаруватому середовищі з просторовою і часовою дисперсією. Анізотропне середовище описується матеріальними рівняннями типу часової згортки з ядрами сприйнятливості, що являють собою тензори другого рангу. Запропонована і чисельно досліджена модель широкосмугового поглинаючого покриття

Девиантное поведение личности и социальная (общественная) безопасность.

В представленной статье авторы акцентируют внимание на том, что в периоды сложных социально-экономических перемен синхронизация неоднозначного процесса адаптации личности в изменившихся условиях происходит не всегда позитивно по причине девиантного поведения, что влияет на общественную безопасность. Модернизация всегда сопровождается обновлением системных связей и появлением специфической рефлексии личности, которая взаимодействуя с социумом, детерминирует изменение социально-психологического климата и направленности общественных отношений в целом. = Particularly relevant to become social (public) safety, studied in the context of the functioning of communication technologies, forms of presentation of information, the work of the media, Internet technology, education, training and conduct of the individual

Point-contact spectroscopy of the nickel borocarbide superconductor YNi2B2C in the normal and superconducting state

Point-contact (PC) spectroscopy measurements of YNi2B2C single crystals in the normal and superconducting (SC) state (T_c=15.4K) for the main crystallographic directions are reported. The PC study reveals the electron-phonon interaction (EPI) spectral function with dominant phonon maximum around 12 meV and further weak structures (hump or kink) at higher energy at about 50 meV. No "soft" modes below 12 meV are resolved in the normal state. The PC EPI spectra are qualitatively similar for the different directions. Contrary, directional study of the SC gap results in \Delta_[100]=1.5 meV for the a direction and \Delta_[001]=2.3 meV along the c axis; however the critical temperature T_c in PC in all cases is near to that in the bulk sample. The value 2\Delta_[001]/kT_c=3.6 is close to the BCS value of 3.52, and the temperature dependence \Delta_[001](T) is BCS-like, while the for small gap \Delta_[100](T) is below BCS behavior at T>T_c/2 similarly as in the two-gap superconductor MgB2. It is supposed that the directional variation \Delta can be attributed to a multiband nature of the SC state in YNi2B2C.Comment: 9 pages, 10 figures, to be published in a special issue of J. Low Temp. Phys. in honour of Prof. H. von Loehneyse

Measurement of the View the tt production cross-section using eμ events with b-tagged jets in pp collisions at √s = 13 TeV with the ATLAS detector

This paper describes a measurement of the inclusive top quark pair production cross-section (σtt¯) with a data sample of 3.2 fb−1 of proton–proton collisions at a centre-of-mass energy of √s = 13 TeV, collected in 2015 by the ATLAS detector at the LHC. This measurement uses events with an opposite-charge electron–muon pair in the final state. Jets containing b-quarks are tagged using an algorithm based on track impact parameters and reconstructed secondary vertices. The numbers of events with exactly one and exactly two b-tagged jets are counted and used to determine simultaneously σtt¯ and the efficiency to reconstruct and b-tag a jet from a top quark decay, thereby minimising the associated systematic uncertainties. The cross-section is measured to be: σtt¯ = 818 ± 8 (stat) ± 27 (syst) ± 19 (lumi) ± 12 (beam) pb, where the four uncertainties arise from data statistics, experimental and theoretical systematic effects, the integrated luminosity and the LHC beam energy, giving a total relative uncertainty of 4.4%. The result is consistent with theoretical QCD calculations at next-to-next-to-leading order. A fiducial measurement corresponding to the experimental acceptance of the leptons is also presented

Search for strong gravity in multijet final states produced in pp collisions at √s=13 TeV using the ATLAS detector at the LHC

A search is conducted for new physics in multijet final states using 3.6 inverse femtobarns of data from proton-proton collisions at √s = 13TeV taken at the CERN Large Hadron Collider with the ATLAS detector. Events are selected containing at least three jets with scalar sum of jet transverse momenta (HT) greater than 1TeV. No excess is seen at large HT and limits are presented on new physics: models which produce final states containing at least three jets and having cross sections larger than 1.6 fb with HT > 5.8 TeV are excluded. Limits are also given in terms of new physics models of strong gravity that hypothesize additional space-time dimensions

Search for TeV-scale gravity signatures in high-mass final states with leptons and jets with the ATLAS detector at sqrt [ s ] = 13TeV

A search for physics beyond the Standard Model, in final states with at least one high transverse momentum charged lepton (electron or muon) and two additional high transverse momentum leptons or jets, is performed using 3.2 fb−1 of proton–proton collision data recorded by the ATLAS detector at the Large Hadron Collider in 2015 at √s = 13 TeV. The upper end of the distribution of the scalar sum of the transverse momenta of leptons and jets is sensitive to the production of high-mass objects. No excess of events beyond Standard Model predictions is observed. Exclusion limits are set for models of microscopic black holes with two to six extra dimensions

Operation and performance of the ATLAS semiconductor tracker

The semiconductor tracker is a silicon microstrip detector forming part of the inner tracking system of the ATLAS experiment at the LHC. The operation and performance of the semiconductor tracker during the first years of LHC running are described. More than 99% of the detector modules were operational during this period, with an average intrinsic hit efficiency of (99.74±0.04)%. The evolution of the noise occupancy is discussed, and measurements of the Lorentz angle, δ-ray production and energy loss presented. The alignment of the detector is found to be stable at the few-micron level over long periods of time. Radiation damage measurements, which include the evolution of detector leakage currents, are found to be consistent with predictions and are used in the verification of radiation background simulations

Measurement of the correlation between flow harmonics of different order in lead-lead collisions at √sNN = 2.76 TeV with the ATLAS detector

Correlations between the elliptic or triangular flow coefficients vm (m=2 or 3) and other flow harmonics vn (n=2 to 5) are measured using √sNN=2.76 TeV Pb+Pb collision data collected in 2010 by the ATLAS experiment at the LHC, corresponding to an integrated luminosity of 7 μb−1. The vm−vn correlations are measured in midrapidity as a function of centrality, and, for events within the same centrality interval, as a function of event ellipticity or triangularity defined in a forward rapidity region. For events within the same centrality interval, v3 is found to be anticorrelated with v2 and this anticorrelation is consistent with similar anticorrelations between the corresponding eccentricities, ε2 and ε3. However, it is observed that v4 increases strongly with v2, and v5 increases strongly with both v2 and v3. The trend and strength of the vm−vn correlations for n=4 and 5 are found to disagree with εm−εn correlations predicted by initial-geometry models. Instead, these correlations are found to be consistent with the combined effects of a linear contribution to vn and a nonlinear term that is a function of v22 or of v2v3, as predicted by hydrodynamic models. A simple two-component fit is used to separate these two contributions. The extracted linear and nonlinear contributions to v4 and v5 are found to be consistent with previously measured event-plane correlations

Search for H→γγ produced in association with top quarks and constraints on the Yukawa coupling between the top quark and the Higgs boson using data taken at 7 TeV and 8 TeV with the ATLAS detector

A search is performed for Higgs bosons produced in association with top quarks using the diphoton decay mode of the Higgs boson. Selection requirements are optimized separately for leptonic and fully hadronic final states from the top quark decays. The dataset used corresponds to an integrated luminosity of 4.5 fb−14.5 fb−1 of proton–proton collisions at a center-of-mass energy of 7 TeV and 20.3 fb−1 at 8 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. No significant excess over the background prediction is observed and upper limits are set on the tt¯H production cross section. The observed exclusion upper limit at 95% confidence level is 6.7 times the predicted Standard Model cross section value. In addition, limits are set on the strength of the Yukawa coupling between the top quark and the Higgs boson, taking into account the dependence of the tt¯H and tH cross sections as well as the H→γγ branching fraction on the Yukawa coupling. Lower and upper limits at 95% confidence level are set at −1.3 and +8.0 times the Yukawa coupling strength in the Standard Model