arXiv subjects

Igor Petrov

Publications and source records attributed to Igor Petrov.

8 recordsLinked to original sources

arXiv2022

Muons in showers with energy $E_{0} \geq$ 5 EeV and QGSjetII-04 and EPOS LHC models of hadronic interactions. Is there a muon deficit in the models?

The paper presents data on the muon component with a threshold $\varepsilon_{thr} \geq$ 1 GeV. Air showers were registered at the Yakutsk array during almost 50 years of continuous air shower observations. The characteristics of muons are compared with calculations of QGSjetII-04 and EPOS LHC models for a proton and an iron nucleus. There is a muon deficit in the models, at energies greater than 5 EeV. To make an agreement between experimental data and simulations on muons, further tuning of the models is required.

astro-ph.HE↗

arXiv2022

On irregularities in the cosmic ray spectrum of $10^{16}-10^{18}$ eV range

Existing small, medium and large arrays for the study of cosmic rays of ultra-high energies are aimed for obtaining information about our galaxy and extragalactic space, namely to search and study astronomical objects that produce the flux of relativistic particles. The drift and interaction of such particles with magnetic fields and shock waves taking place in interstellar space causes the same interest. The shape of the energy spectrum of cosmic rays in the energy range $10^{15}-10^{18}$ eV, where the "knee" and the "second knee" are observed, can be formed as a superposition of the partial spectra of various chemical elements. Verification of galactic models, using recent experimental spectral data, makes it possible to study the nature of the galactic and extragalactic components of cosmic rays. The paper presents the result of the energy spectrum of cosmic rays in the range $10^{16}-10^{18}$ eV of measurements obtained with the Small Cherenkov array -- a part of the Yakutsk array.

astro-ph.HE↗

arXiv2020

Mass composition of cosmic rays determined by muon fraction with $\varepsilon_{thr.} \geq$ 1 GeV in air showers with energy greater than 5 EeV

The ratio of the number of muons with a threshold of 1 GeV and charged particles at a distance of 600 m from the axis is analyzed. Air showers with energies above 5 EeV and zenith angles with less than 60 degrees are considered. Comparison of experimental data with calculations by the QGSJETII-04 model for various primary nuclei, including a gamma ray, showed that the mass composition of cosmic rays up to energies of $\sim$ 10 EeV mainly consists of protons and helium nuclei, with a small number of heavy nuclei. Data include air showers with a very low muon content, which are assumed to be produced by primary gamma rays.

astro-ph.HE↗

arXiv2020

Numerical modeling of thin anisotropic composite membrane under dynamic load

This work aims to describe a mathematical model and a numerical method to simulate a thin anisotropic composite membrane moving and deforming in 3D space under a dynamic load of an arbitrary time and space profile. The model and the method allow to consider problems when quasi static approximation is not valid, and elastic waves caused by the impact should be calculated. The model and the method can be used for numerical study of different processes in thin composite layers, such as shock load, ultrasound propagation, non-destructive testing procedures, vibrations. The thin membrane is considered as 2D object in 3D space, this approach allows to reduce computational time still having an arbitrary material rheology and load profile.

math.NA↗

arXiv2019

Mass composition of cosmic rays above 0.1 EeV by the Yakutsk array data

The paper presents the results of the longitudinal development of extensive air showers (X$_{max}$) of ultra-high energies and mass composition of cosmic rays. The measurements of X$_{max}$ are based on data from observations of the Cherenkov radiation at the Yakutsk array for the period 1974-2014. The cascade curves of individual showers and the depth of maximum X$_{max}$ were reconstructed over the energy range 10$^{16}$-5.7$\cdot$10$^{19}$ eV. It is shown that the displacement rate of the parameter dX$_{max}$ / dE in the atmosphere is nonlinear and depends on the energy. Such a feature indicates a change in mass composition, which is confirmed by fluctuations of X$_{max}$ in this energy region. The composition of cosmic rays was determined by interpolation using the QGSJetII-04 model.

astro-ph.HE↗

arXiv2014

Atmospheric Circulation Influence During Winter on Measurements at Yakutsk Array

The paper presents long-term observations of the atmosphere in Yakutsk region. Analysis of the data for 40 year period indicates a gradual strengthening of cyclonic activity in the region and hence the increase of the average winter temperature, increase variations of the rest atmosphere, which greatly softens the continental climate of Central Yakutia.

astro-ph.IM↗

arXiv2014

Optic detectors calibration for measuring ultra-high energy extensive air showers Cherenkov radiation by 532 nm laser

Calibration of a PMT matrix is crucial for the treatment of the data obtained with Cherenkov tracking detector. Furthermore, due to high variability of the aerosol abundance in the atmosphere depending on season, weather etc. A constant monitoring of the atmospheric transparency is required during the measurements. For this purpose, besides traditional methods, a station for laser atmospheric probing is used.

astro-ph.IM↗

arXiv2014

Radio signal correlation at 32 MHz with extensive air showers parameters

The paper present correlation of radio signal with air shower parameters: shower energy E0 and depth of maximum Xmax. It is shown that from radio emission measurements of air showers one can obtain individual showers parameters and mass composition of cosmic rays. We also derived generalized formula for calculating energy of the air showers.

astro-ph.IM↗