A5065732073- Solar and Space Plasma Dynamics
- Ionosphere and magnetosphere dynamics
- Geomagnetism and Paleomagnetism Studies
- Magnetic confinement fusion research
- Fluid Dynamics and Turbulent Flows
- Dust and Plasma Wave Phenomena
- Nonlinear Waves and Solitons
- Astro and Planetary Science
- Stellar, planetary, and galactic studies
- Nonlinear Photonic Systems
- Oceanographic and Atmospheric Processes
- Ocean Waves and Remote Sensing
- Geophysics and Gravity Measurements
- Spacecraft and Cryogenic Technologies
- Astrophysics and Star Formation Studies
- Tropical and Extratropical Cyclones Research
- Cold Atom Physics and Bose-Einstein Condensates
- Characterization and Applications of Magnetic Nanoparticles
- Atmospheric Ozone and Climate
- Plasma Diagnostics and Applications
- Advanced Fiber Laser Technologies
- Elasticity and Material Modeling
- Advanced Mathematical Physics Problems
- High-pressure geophysics and materials
- Earthquake Detection and Analysis
Space Research Institute
2015-2024
University of Sheffield
2015-2024
Lomonosov Moscow State University
2009-2024
Moscow Center For Continuous Mathematical Education
2020
Russian Academy of Sciences
1995-2015
Indiana University
2015
Moscow State University
2009
University of St Andrews
1998-2007
City, University of London
2006
Google (United States)
2005
Motivated by recent Transition Region and Coronal Explorer (TRACE) observations of damped oscillations in coronal loops, we consider analytically the motion an inhomogeneous magnetic tube radius a zero-β plasma. An initially perturbed may vibrate its kink mode oscillation, but those vibrations are damped. The damping is due to resonant absorption, acting regions tube, which leads transfer energy from Alfvén (azimuthal) within layer. We determine explicitly decrement γ (decay time γ-1) for...
We consider transverse oscillations of coronal loops that have both variable circular cross-sectional area and plasma density in the longitudinal direction. The primary focus this paper is to study eigenmodes these oscillations. Implementing method asymptotic expansions with ratio loop radius length as a small parameter, second-order ordinary differential equation derived describing displacement axis. Together boundary conditions at tube ends follow from frozen-in condition, constitutes...
Abstract In this paper we study the propagation of nonlinear ion-acoustic waves in plasmas with negative ions. The Gardner equation governing these ion concentration close to critical is derived. weakly theory modulational instability based on use Schrödinger discussed. investigation dynamics modulationally unstable quasi-harmonic wavepackets carried out by numerical solution equation. results are compared predictions theory.
Aims. We investigate the spatial damping of propagating kink waves in an inhomogeneous plasma. In limit a thin tube surrounded by transition layer, analytical formulation for driven from bottom boundary corona is presented.
The one-dimensional oblique propagation of magnetohydrodynamic waves with arbitrary amplitudes in a Hall plasma isotropic pressure is studied under assumption that the β large. It shown wave evolution described by derivative nonlinear Schrödinger equation (DNLS).
We present results of a new time-dependent kinetic model the H atom penetration through solar wind – interstellar medium interaction region. A 6D (time, two dimensions in space, and three velocity-space) equation for atoms was solved self-consistently with Euler equations charged components. study response region to 11-year cycle variations dynamic pressure. It is shown that termination shock location varies within ±7 AU, heliopause variation ~4 bow negligible. At large heliocentric...
Soon after coronal loop oscillations were observed by TRACE spacecraft for the first time in 1999, various theoretical models have been put forward to explain rapid damping of these intriguing objects. Coronal are often interpreted as fast kink modes a straight cylindrical magnetic flux tube with immovable edges modelling dense photospheric plasma at ends loop. Taking this model basis we use cold approximation and consider be thin simplify problem able deal it analytically. In its...
The presence of magneto-acoustic waves in magnetic structures the solar atmosphere is well-documented. Applying technique magneto-seismology (SMS) allows us to infer background properties these structures. Here, we aim identify observed and study within lower atmosphere. Using Dutch Open Telescope (DOT) Rapid Oscillations Solar Atmosphere (ROSA) instruments, captured two series high-resolution intensity images with short cadence isolated pores. Combining wavelet analysis empirical mode...
The propagation of nonlinear nonaxisymmetric waves along a magnetic tube in an incompressible plasma embedded magnetic-free is studied. and parameters the core as well external are constant. Between there thin annulus where Alfvén speed monotonically decreases to zero. In this cylindrical surface phase global wave matches local speed. vicinity efficient conversion energy waves. This results resonant absorption and, consequence, damping. amplitude assumed be small used parameter singular...
The damping of kink oscillations a thin magnetic tube due to mode conversion, also called resonant absorption, is studied. consists homogeneous core region and an inhomogeneous annulus, where the density monotonically decreases from its value in surrounding plasma. annulus assumed be thin, so study carried out boundary approximation. equation governing amplitude variation derived. initial problem for this solved damping. This means that, particular, we transient state before loop oscillates...
In this paper, we study kink waves in twisted magnetic tubes. the equilibrium state there is electrical current with constant density inside tube directed along axis. This creates azimuthal field magnitude proportional to distance from axis and inversely outside tube. We derive dispersion equations for propagating unstable perturbations long wavelength approximation. show that are no solutions equation determining frequencies of perturbations, which implies modes. both case when plasma...
Abstract In a previous paper, we computed the energy density and nonlinear cascade rate for transverse kink waves using Elsässer variables. this focus on standing waves, which are impulsively excited in coronal loops by external perturbations. We present an analytical calculation to compute damping time due development of Kelvin–Helmholtz instability. The main result is that inversely proportional oscillation amplitude. compare times from our formula with results numerical simulations...
Motivated by recent Transition Region and Coronal Explorer (TRACE) observations of damped oscillations in coronal loops, Ruderman & Roberts ([CITE]), studied resonant damping kink thin straight magnetic tubes a cold plasma. In their analysis, considered with circular cross-sections. We extend analysis for elliptic find that there are two infinite sequences the eigenfrequencies tube oscillations, , . The correspond to modes nodes at boundary. particular, modes. These linearly polarized...
This paper reviews a recent development in the theory of resonant MHD waves non-uniform plasmas. An asymptotic analysis equations for plasmas with high magnetic Reynolds numbers has shown that slow and Alfvén obey conservation laws jump conditions across dissipative layer. These specify dominant dynamics waves. In combination they enable us to understand basic physics also help interpretation results large scale numerical simulations resistive MHD. They can be used design an accurate...