Dilaton generation by electromagnetic field of rotating magnetic dipole momentum of neutron star in it's own gravitational field
Dilaton generation by electromagnetic field of rotating magnetic dipole momentum of neutron star in it's own gravitational field
M. O. Astashenkov$^{1,2}$, V. I. Denisov$^{1,2}$, I. P. Denisova$^{3,4}$
According to dilaton-Maxwell theory, dilatons can be generated by electromagnetic fields with a nonzero electromagnetic field invariant $F_{mn}F^{mn}$, where $F_{mn}$ is the tensor of the electromagnetic field. The paper considers the generation of dilatons in the electromagnetic field of a rotating magnetic dipole moment of a neutron star, taking into account its own gravitational field. Solutions of dilaton field equations were obtained in the weak gravitational field approximation. Based on them, the intensity of dilaton generation was obtained in the approximation $r_g/R_S\ll 1$, where $r_g$ is the Schwarzschild radius and $R_S$ is the radius of the neutron star. It is shown that the intensity of dilaton generation from the rotating magnetic dipole moment of a neutron star is lower in the first order of magnitude than in the case of a flat space-time.
Show AbstractIntegration of Geophysical Time Series Analysis Methods into an Open-Source Software Package
Integration of Geophysical Time Series Analysis Methods into an Open-Source Software Package
M. E. Arzangulyan, N. E. Shapkina
The article presents an open-source software complex for analyzing time series of geophysical quantities. The complex integrates various analytical methods: statistical (ARIMA, SARIMA), spectral (Fourier transform, wavelet analysis), neural network (LSTM), and morphological approaches, as well as tools for anomaly detection. The key features include modular architecture, synthetic data generation capabilities, flexible algorithm parameterization, and interactive visualization of results. The software complex is already applied in researches of our scientific group, particularly for analyzing meteorological data from carbon monitoring sites. The open-source nature ensures the possibility of adapting functionality for specific tasks and further development of the complex by the scientific community.
Show AbstractDetermination of $\alpha$-decay energies in the heavy element region
Determination of $\alpha$-decay energies in the heavy element region
V. S. Ulianova$^1$, D. F. Bayramov$^1$, S. V. Sidorov$^2$, M. E. Stepanov$^1$, K. A. Stopani$^2$, T. Yu. Tretyakova$^{1,2}$
Since the discovery of $\alpha$-decay, one of the main decay channels of unstable atomic nuclei, its intensive study has not ceased. These studies are especially relevant in the field of superheavy elements, since observation of the corresponding chain of $\alpha$-decays is necessary for the identification of new isotopes. Methods using mass ratios have long been successfully used to predict the masses of unknown nuclei. The efficiency of the method based on the residual np-interaction coefficient was previously demonstrated on the characteristics of $\alpha$-decay for isotopes with Z ≤ 106. In this paper, the results for nuclei up to Z = 118 are presented, obtained on the basis of experimental values of $Q_\alpha$. Estimates of energy and $alpha$-decay rates obtained from AME2020 and NUBASE2020 data are in good agreement with the 2022–2024 experimental data.
Show AbstractNumerical modeling of temperature field in the system of graphite crucibles during electric arc synthesis of metal carbides and borides
Numerical modeling of temperature field in the system of graphite crucibles during electric arc synthesis of metal carbides and borides
D. E. Stovpets$^1$, G. A. Bleykher$^1$, A. Y. Pak$^2$
The increasing demand for materials with unique physical properties creates the need for new methods of obtaining such materials. One of the most promising is the method of synthesis of substances using energy of arc discharge generated in atmospheric conditions, in this way it is possible to obtain carbides and borides of various metals. This method is distinguished by the possibility of realization in open air environment and relatively short duration of working process. One of the problems that arise in the development of technologies based on this method is to find the most appropriate operating parameters of the set. The solution of this problem only by experiment is very resource-consuming. It is advisable to use numerical modeling here. The proposed paper describes a numerical model of thermal processes in an electric arc reactor based on the heat conduction equation with a surface heat source. Using experimental measurements the heat transfer coefficient between the reactor elements is determined. The operability of the developed numerical model and the method of setting the surface heat source is demonstrated. The numerical model will be used to optimize the parameters of the arc plasma source in the practical implementation of materials synthesis using the method described here.
Show AbstractThe effect of proton radiation on K-208 glass
The effect of proton radiation on K-208 glass
I. S. Kuznetsov
As a result of the experimental study of the effect of protons with energies of 20 and 30 keV, typical for hot magnetospheric plasma (HMP), on the protective glass for K-208 solar batteries, carried out using an atomic force microscope, it was found that gas-filled bubbles and microcracks are formed in the glass in the case when the proton energy is 30 keV. The initial hypothesis is that the specified structural changes occur due to the field migration of sodium ions in the field of protons injected into the glass. In this paper, the passage of proton radiation with energies of 20 and 30 keV is simulated using the Geant4 package. It was found that the depths corresponding to the peak concentrations of protons injected into the K-208 glass are 240 and 350 nm, respectively, and the overwhelming majority of protons settle in a thin layer near these depths. The paper also presents the energy release curves for protons with the specified energies. It has been established that the main mechanism of energy loss by protons is ionization braking, which occurs intensively from the very beginning of proton movement through glass. Based on the results obtained using Geant4, the electric field inside the glass is calculated in cases where the sample is on a dielectric substrate and on a grounded metal substrate.
Show AbstractDevelopment of a setup for calibration of ionization chambers and feedback sensors of the extracted carbon ion beam with activation detectors
Development of a setup for calibration of ionization chambers and feedback sensors of the extracted carbon ion beam with activation detectors
A. G. Vasilyeva$^1$, M. Yu. Kostin$^1$, V. A. Pikalov$^1$, A. A. Yanovich$^1$
This paper presents a radiometric experimental setup operating on the γ-γ-coincidence principle for calibration of ionization chambers and feedback sensors of the extracted carbon ion beam with activation detectors. In this case, an activation detector made of pure carbon with a natural isotope mixture and the 12C(12C,X)11C reaction are used. The setup ensures the measurement of sample activity with an error of about 3%. A block diagram of the setup and its description are provided, as well as a description of the process of measuring its registration efficiency using a control reference source 22Na. The registration efficiency of the radiometric setup was measured and is estimated at 60.1%. The working prototype of this radiometric setup has already been used for several sessions of operation of the U-70 accelerator complex when working with carbon ions with an energy of 400-450 MeV/nucleon to calibrate the plane-parallel ionization chamber developed and manufactured by IHEP. A manual for the operation of the setup and a technique for performing measurements are being prepared.
Show AbstractDevelopment of a graphical shell for the ion beam therapy planning system
Development of a graphical shell for the ion beam therapy planning system
E. V. Parmenova, O. P. Yushchenko
A description of the graphical shell is presented. It was developed for the planning system of the projected ion radiation therapy center on the basis of the operating Accelerator complex U-70 of the NRC “Kurchatov Institute” - IHEP in Protvino. The graphical interface is implemented in Qt. Its functionality is based on the modular base of the ion beam therapy planning system. The current version of the shell is related to the implementation of the module for working with DICOM files.
Show AbstractGravitational bremsstrahlung by electromagnetic interaction
Gravitational bremsstrahlung by electromagnetic interaction
Yu. V. Grats, P. -. Spirin
We revisit the problem of classical gravitational bremsstrahlung which occurs by collisions of ultra-relativistic charges. The collision is characterized by the Lorentz-factor~$\gamma$ and the impact parameter~$b$. Within the perturbation theory, we compute the total energy, radiated as a gravitational wave, as well as numerous spectral, angular and polarization distributions. The most of radiation is emitted into a beaming cone with linear angle of order~$1/\gamma$. The average frequency is of order~$\gamma^2/b$.
Show AbstractAtomic H over crystal surface: a variational approach
Atomic H over crystal surface: a variational approach
A. V. Tolokonnikov, P. K. Silaev
We study the behavior of the lowest electron level of a hydrogen atom confined in the semi-infinite space with a plane surface applying variational methods. The properties of the adsorbent are modeled by the parameter of the Robin boundary condition imposed on the electron wave functions at the boundary. We consider the case of crystalline adsorbent, so we assume that the parameter in Robin condition is a periodoc function. It is shown that the periodicity of the parameter should be taken into account when choosing a trial function. Trial wave funtion should provide the correct relationship between the normal derivative and the wave function value at each point of the boundary and have an antinode at the vicinity of the atomic nucleus. We perform a сomparison of the results obtained via the variational approach and via direct numerical calculations.
Show AbstractAmplitude-phase characteristics of images of fractal structures
Amplitude-phase characteristics of images of fractal structures
P. V. Korolenko$^{1,2}$, R. T. Kubanov$^1$, A. Yu. Mishin$^1$
Based on numerical modeling, the scaling (scale invariance) of spatial spectra of amplitude and phase images of fractal structures in a general optical system was estimated. The relevance of the study is due to the key role of spatial radiation spectra in the processes of optical information perception and processing. Particular attention is paid to the properties of stochastic light structures, which are widely used in art therapy and ophthalmology. For their construction, the properties of the two-dimensional Mandelbrot-Weierstrass function, as well as the properties of the stochastic model of constructive fractals, were used. Despite the disordered (speckle-like) nature of the field distribution in the generated structures, their spatial spectra had a fractal shape with clearly expressed scaling. After passing through the optical system of the initial field distribution, the spectrum contrast decreased, but the shape of the distribution of low-frequency components had a certain stability. Both amplitude and phase images had this property. With the growth of the fractal dimension of radiation, the region of stable arrangement of spectral components expanded, and with the broadening of the scattering function of the optical system, it sharply decreased. The scaling characteristics in images formed in coherent and incoherent light were compared. Their comparison showed that due to the wider transfer function of the optical system, distortions of spatial spectra in incoherent light are less significant. The study indicates the prospects of using fractal speckle distributions in medicine during light therapy sessions.
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