Chiral color symmetry and possible G′G'-boson effects at the Tevatron and LHC

A gauge model with chiral color symmetry is considered and possible effects of the color $G'$-boson octet predicted by this symmetry are investigated in dependence on two free parameters, the mixing angle $\theta_G$ and $G'$ mass $m_{G'}$. The allowed region in the $m_{G'} - \theta_G$ plane is found from the Tevatron data on the cross section $\sigma_{t\bar{t}}$ and forward-backward asymmetry $A_{\rm FB}^{p \bar p}$ of the $t\bar{t}$ production. The mass limits for the $G'$-boson are shown to be stronger than those for the axigluon. A possible effect of the $G'$-boson on the $t\bar{t}$ production at the LHC is discussed and the mass limits providing for the $G'$-boson evidence at the LHC are estimated in dependence on $\theta_G$.Comment: 11 pages, 2 figures, accepted for publication in Modern Physics Letters

Probing a Nucleon Spin Structure at TESLA by the Real Polarized Gamma Beam

The recent proposals concerning the usage of the real polarized gamma beam, obtained by the Compton backscattering of the laser photons off the electron beams from either the linear or circular accelerators were considered. The heavy quark photoproduction process giving a unique opportunity to measure polarized gluon distribution was investigated.Comment: 16 pages, LATEX, 6 figures (EPS

About actual contradiction in geotechnical design and optimal way of it resolution

The paper describes serious and fundamental contradiction in geotechnical design, which manifested itself to the greatest extent when designing the foundations of high-rise buildings in the third quarter of the 20th century has begun to form from the late of the 19th century to the 20th years of the 20th century. Prime cause of this contradiction is in complex physical structure of soils, complex nature of their formation and, therefore, in complex form of their deformation. The article also notes the high technical and economic efficiency of using realistic physically nonlinear soil models in the design of geotechnical parts of buildings and structures. In this case such a designing is most effective when using the parameters of nonlinear models determined from data of in-situ tests. © Published under licence by IOP Publishing Ltd

Experience in designing the foundations of a multi-storey building on the eluvial soils of the Urals using a model of non-linear soil deformation

The article describes an example of the first design of the foundation of a high-rise building in the Middle Urals using a non-linear soil model that reflects the real deformation properties of the soil. The use of an effective model that reflects the real deformation properties of the soil has allowed to reduce the cost of the foundation by more than two times while increasing of its reliability. © Published under licence by IOP Publishing Ltd

Stages of introducing nonlinear soil model into design practice in Russia

The paper describes more important stages of introducing nonlinear soil model into design practice in Russia. Results of laboratory and in-situ verification studies are analyzed. Some examples of objects which geotechnical parts were designed using a physically and geometrically nonlinear soil model are given and discussed. Since the soil is a natural media, the values of its mechanical characteristics (parameters) should be determined from in-situ static tests, for example, using pressuremeter devices, that allows to ensure the necessary accuracy in about 25% of the design geotechnical output data. © 2023 Author(s)

The Qt distribution of the Breit current hemisphere in DIS as a probe of small-x broadening effects

We study the distribution 1/sigma dsigma/dQt, where Qt is the modulus of the transverse momentum vector, obtained by summing over all hadrons, in the current hemisphere of the DIS Breit frame. We resum the large logarithms in the small Qt region, to next-to--leading logarithmic accuracy, including the non-global logarithms involved. We point out that this observable is simply related to the Drell-Yan vector boson and predicted Higgs Qt spectra at hadron colliders. Comparing our predictions to existing HERA data thus ought to be a valuable source of information on the role or absence of small-x (BFKL) effects, neglected in conventional resummations of such quantities.Comment: 16 pages, 3 figures, uses JHEP3.cl

Визуализация потока воздуха в вихревой трубе с использованием различных моделей турбулентности

Visualization of air flow in Ranque-Hilsch vortex tube performed by numerical simulations with standard k-ε and SAS-SST turbulence models is presented in the paper. SAS-SST turbulence model predicted the existence of secondary largescale vortex structures within the computational domain instead k-ε model showed axisymmetrical flow. Existence of large-scale secondary vortex structures is in agreement with experimental data.В статье представлены результаты визуализации потока воздуха в вихревой трубе Ранка-Хилша, выполненной с помощью численного моделирования. Были использованы k-ε и SAS-SST модели турбулентности. SAS-SST модель турбулентности показала наличие вторичных крупномасштабных вихревых структур в расчетном домене, в отличие от k-ε модели. Факт наличия крупномасштабных вторичных вихревых структур хорошо согласуется с экспериментальными данными

Magneto-optical properties of Au upon the injection of hot spin-polarized electrons across Fe/Au(001) interfaces

We demonstrate a novel method for the excitation of sizable magneto-optical effects in Au by means of the laser-induced injection of hot spin-polarized electrons in Au/Fe/MgO(001) heterostructures. It is based on the energy- and spin-dependent electron transmittance of Fe/Au interface which acts as a spin filter for non-thermalized electrons optically excited in Fe. We show that after crossing the interface, majority electrons propagate through the Au layer with the velocity on the order of 1 nm/fs (close to the Fermi velocity) and the decay length on the order of 100 nm. Featuring ultrafast functionality and requiring no strong external magnetic fields, spin injection results in a distinct magneto-optical response of Au. We develop a formalism based on the phase of the transient complex MOKE response and demonstrate its robustness in a plethora of experimental and theoretical MOKE studies on Au, including our ab initio calculations. Our work introduces a flexible tool to manipulate magneto-optical properties of metals on the femtosecond timescale that holds high potential for active magneto-photonics, plasmonics, and spintronics