НС

Н. С. Петрухин

Nizhny Novgorod Research Institute of Traumatology and Orthopedics

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

МС

М. С. Рудерман

Space Research Institute

Efim Pelinovsky

Institute of Applied Physics

Tatiana Talipova

Institute of Applied Physics

V. V. Tamoǐkin

Radiophysical Research Institute

Ekaterina Batsyna

National Research University Higher School of Economics

L. A. Ostrovskij

S. M. Faǐnshteǐn

Institute of Terrestrial Magnetism Ionosphere and Radio Wave Propagation

Ekaterina Shurgalina

Nizhny Novgorod State Pedagogical University

Karam Bahari

Razi University

Cooperative Institutions

Russian Academy of Sciences

Nizhny Novgorod State Pedagogical University

Nizhny Novgorod State Technical University

Radiophysical Research Institute

National Research University Higher School of Economics

Institute of Applied Physics

University of Sheffield

V.I. Il'ichev Pacific Oceanological Institute

Space Research Institute

Lomonosov Moscow State University

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

Nonreflected vertical propagation of acoustic waves in a strongly inhomogeneous atmosphere

Izvestiya Atmospheric and Oceanic Physics (2012)

Н. С. Петрухин Efim Pelinovsky Tatiana Talipova

Energy flux

Reflection

10.1134/s0001433812020090

Cite

Citations (14)

Decayless Kink Oscillations Excited by Random Driving: Motion in Transitional Layer

Solar Physics (2021)

М. С. Рудерман Н. С. Петрухин Efim Pelinovsky

Abstract In this article we study the plasma motion in the transitional layer of a coronal loop randomly driven at one of its footpoints in the thin-tube and thin-boundary-layer (TTTB) approximation. We introduce the average of the square of a random function with respect to time. This average can be considered as the square of the oscillation amplitude of this quantity. Then we calculate the oscillation amplitudes of the radial and azimuthal plasma displacement as well as the perturbation of the magnetic pressure. We find that the amplitudes of the plasma radial displacement and the magnetic-pressure perturbation do not change across the transitional layer. The amplitude of the plasma radial displacement is of the same order as the driver amplitude. The amplitude of the magnetic-pressure perturbation is of the order of the driver amplitude times the ratio of the loop radius to the loop length squared. The amplitude of the plasma azimuthal displacement is of the order of the driver amplitude times $\text{Re}^{1/6}$ Re 1 / 6 , where Re is the Reynolds number. It has a peak at the position in the transitional layer where the local Alfvén frequency coincides with the fundamental frequency of the loop kink oscillation. The ratio of the amplitude near this position and far from it is of the order of $\ell$ ℓ , where $\ell$ ℓ is the ratio of thickness of the transitional layer to the loop radius. We calculate the dependence of the plasma azimuthal displacement on the radial distance in the transitional layer in a particular case where the density profile in this layer is linear.

Oscillation (cell signaling)

10.1007/s11207-021-01867-5

Cite

Citations (12)

The effect of flow on transverse oscillations of two parallel magnetic tubes

Monthly Notices of the Royal Astronomical Society (2023)

М. С. Рудерман Н. С. Петрухин

ABSTRACT We study oscillations of two parallel interacting magnetic tubes in the presence of plasma flow along the tubes. Using the cold plasma and thin tube approximations we derive the system of two equations describing these oscillations. This system of equations is valid for equilibria where the plasma density and flow velocity can vary along the tube axes and in time. This system of equations is used to study the effect of flow in the tubes on the frequency of standing waves. There are two modes of oscillations, fast and slow. We calculated the dependence of frequencies of fast and slow modes of the Alfvén Mach number. We found that the effect of flow in coronal loops on the oscillation frequency is fairly weak for typical flow velocities observed in coronal loops. However it can be substantial in the case of prominence threads. We discuss the implication of the obtained results on coronal seismology.

Oscillation (cell signaling)

10.1093/mnras/stad1530

Cite

Citations (3)

Non-reflective Propagation of Kink Pulses in Magnetic Waveguides in the Solar Atmosphere

Solar Physics (2015)

Н. С. Петрухин М. С. Рудерман Efim Pelinovsky

Flux tube

Coronal loop

Reflection

10.1007/s11207-015-0682-3

Cite

Citations (10)

Effect of Transitional Layer on Frequency of Kink Oscillations

Solar Physics (2022)

М. С. Рудерман Н. С. Петрухин

Abstract In this article we study the effect of a transitional layer in a magnetic tube on the real part of the frequencies of kink oscillations. In our analysis, we use the model of a straight magnetic tube with the density and cross-section radius varying along the loop, and the thin-tube thin-boundary (TTTB) approximation. First, we calculate the correction to the fundamental frequency and show that it is positive and of the order of the ratio of the transitional layer thickness to the loop radius $\ell $ ℓ . The increase in the fundamental frequency results in the decrease in the estimate of the magnetic-field magnitude. Then we study the effect of the transitional layer on the ratio between the fundamental frequency and the first overtone frequency that is used for estimating the atmospheric scale height. We show that the correction to the frequency ratio is of the order of $\ell ^{2}$ ℓ 2 , and thus it can be neglected for moderate values of $\ell $ ℓ .

10.1007/s11207-022-02008-2

Cite

Citations (3)

On the Ratio of Periods of the Fundamental Harmonic and First Overtone of Magnetic Tube Kink Oscillations

Solar Physics (2016)

М. С. Рудерман Н. С. Петрухин Efim Pelinovsky

Overtone

Aspect ratio (aeronautics)

Harmonic

Mass ratio

Density ratio

Flux tube

10.1007/s11207-016-0893-2

Cite

Citations (31)

Penetration of internal waves into the ocean’s thickness

Oceanology (2009)

Tatiana Talipova Efim Pelinovsky Н. С. Петрухин

Penetration (warfare)

Mode (computer interface)

10.1134/s0001437009050038

Cite

Citations (11)

Nonlinear Generation of Fluting Perturbations by Kink Mode in a Twisted Magnetic Tube

Solar Physics (2022)

М. С. Рудерман Н. С. Петрухин

Abstract We study the excitation of fluting perturbations in a magnetic tube by an initially imposed kink mode. We use the ideal magnetohydrodynamic (MHD) equations in the cold-plasma approximation. We also use the thin-tube approximation and scale the dependent and independent variables accordingly. Then we assume that the dimensionless amplitude of the kink mode is small and use it as an expansion parameter in the regular perturbation method. We obtain the expression for the tube boundary perturbation in the second-order approximation. This perturbation is a superposition of sausage and fluting perturbations.

Dimensionless quantity

Kink instability

Flux tube

10.1007/s11207-022-02054-w

Cite

Citations (6)

Resonant damping and instability of propagating kink waves in flowing and twisted magnetic flux tubes

Monthly Notices of the Royal Astronomical Society (2020)

Karam Bahari Н. С. Петрухин М. С. Рудерман

ABSTRACT We study the propagation and stability of kink waves in a twisted magnetic tube with the flow. The flow velocity is assumed to be parallel to the magnetic field, and the magnetic field lines are straight outside the tube. The density is constant inside and outside of the tube, and it monotonically decreases from its value inside the tube to that outside in the transitional or boundary layer. The flow speed and magnetic twist monotonically decrease in the transitional layer from their values inside the tube to zero outside. Using the thin tube and thin boundary layer (TTTB) approximation, we derived the dispersion equation determining the dependence of the wave frequency and decrement/increment on the wavenumber. When the kink wave frequency coincides with the local Alfvén frequency at a resonant surface inside the transitional layer, the kink wave is subjected to either resonant damping or resonant instability. We study the properties of kink waves in a particular unperturbed state where there is no flow and magnetic twist in the transitional layer. It is shown that in a tube with flow, the kink waves can propagate without damping for particular values of the flow speed. Kink waves propagating in the flow direction either damp or propagate without damping. Waves propagating in the opposite direction can either propagate without damping, or damp, or become unstable. The theoretical results are applied to the problem of excitation of kink waves in spicules and filaments in the solar atmosphere.

Flux tube

Magnetic damping

Dispersion relation

Wavenumber

Kink instability

10.1093/mnras/staa1442

Cite

Citations (15)

Phase mixing of Alfvén waves in axisymmetric non-reflective magnetic plasma configurations

Monthly Notices of the Royal Astronomical Society (2017)

Н. С. Петрухин М. С. Рудерман Ekaterina Shurgalina

We study damping of phase-mixed Alfvén waves propagating in non-reflective axisymmetric magnetic plasma configurations. We derive the general equation describing the attenuation of the Alfvén wave amplitude. Then we applied the general theory to a particular case with the exponentially divergent magnetic field lines. The condition that the configuration is non-reflective determines the variation of the plasma density along the magnetic field lines. The density profiles exponentially decreasing with the height are not among non-reflective density profiles. However, we managed to find non-reflective profiles that fairly well approximate exponentially decreasing density. We calculate the variation of the total wave energy flux with the height for various values of shear viscosity. We found that to have a substantial amount of wave energy dissipated at the lower corona, one needs to increase shear viscosity by seven orders of magnitude in comparison with the value given by the classical plasma theory. An important result that we obtained is that the efficiency of the wave damping strongly depends on the density variation with the height. The stronger the density decrease, the weaker the wave damping is. On the basis of this result, we suggested a physical explanation of the phenomenon of the enhanced wave damping in equilibrium configurations with exponentially diverging magnetic field lines.

Alfvén wave

10.1093/mnras/stx2914

Cite

Citations (7)