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## Электростатическая турбулентность в перепадах электронной температуры солнечной атмосферы

Письма в Астрономический журнал. 2015. Т. 41. № 10. С. 651-656.

The connection of between the formation and properties of areas characterized by the sharp gradient of electron temperature, with electrostatic turbulence, providing high a high effective electrons collision frequency and a low thermal conductivity of medium, is discussed. Simple dependences for the thermal conductivity, effective collision frequency and noise electric fields are obtained. For a tube with a relatively weak magnetic field, which passes from the chromosphere into the crown, on the basis of the known experimental models of solar atmosphere, an altitude dependence of the thermal conductivity and value of noise electric fields is estimated.

Bespalov P. A., O.N. Savina, Astronomy Letters 2015 Vol. 41 No. 10 P. 601-605

We discuss the connection of the formation and properties of solar atmosphere transition region
characterized by a steep electron temperature gradient with electrostatic turbulence, which provides a high
effective electron collision frequency and a low thermal conductivity of the medium. A simple dependence
of the noise electric field in the transition region on the effective collision frequency has ...

Added: September 30, 2015

Savina O. N., Bespalov P. A., Central European Astrophysical Bulletin 2011 Vol. 35 No. 1 P. 83-91

Within the framework of model calculations the possibility of occurrence of the ion-acoustic oscillation instability in a plasma without current and particle fluxes, but with an anisotropic distribution function, which corresponds to heat flux is shown. The model distribution function was selected taking into account the medium conditions. The increment of ion-acoustic oscillation is investigated ...

Added: December 12, 2012

Bespalov P. A., Savina O. N., Письма в Астрономический журнал 2008 Т. 34 № 5 С. 378-386

The generalized Wiedemann-Franz law for a nonisothermal quasi-neutral plasma with developedion-acoustic turbulence and Coulomb collisions has been proven. The results obtained are used to explain the anomalously low thermal conductivity in the chromosphere-corona transition region of the solar atmosphere. Model temperature distributions in the lower corona and the transition region that correspond to well-known experimental ...

Added: December 12, 2012

Bespalov P. A., Savina O. N., Письма в Астрономический журнал 2009 Т. 35 № 5 С. 382-388

Based on model calculations, we show that ion-acoustic oscillations can be excited by heat fluxes in a plasma. We discuss the probable effect of ion-acoustic oscillations on the formation of temperature gradients at critical heat fluxes. The local critical heat flux in the transition region of the solar atmosphere is close to the well-known experimental ...

Added: December 12, 2012

Bespalov P. A., Savina O.N., Central European Astrophysical Bulletin 2015 Vol. 39 P. 43-50

Special features of the ion-acoustic oscillation instability in the transition region
of a quiet solar atmosphere are examined. A model of electron distribution function,
which corresponds to the heat flux, under condition of absence of a particular beam, is
analyzed. It is shown that the heat flux-related anisotropy of the distribution function is
sufficient for the achievement of the ...

Added: November 26, 2014

Kolokolov I., Turitsyn K., Journal of Experimental and Theoretical Physics 2002 Vol. 94 No. 6 P. 1193-1200

For the field u(x, t) governed by the Burgers equation with a thermal noise, short-time asymptotics
of multipoint correlators are obtained. Their exponential parts are independent of the correlator number. This
means that they are determined by a single rare fluctuation and exhibit the intermittency phenomenon ...

Added: February 25, 2017

Pelinovsky E., E.G. Shurgalina, Sergeeva A. et al., Physical Letters A 2013 Vol. 377 No. 1 P. 272-275

Two-soliton interactions play a definitive role in the formation of the structure of soliton turbulence in integrable systems. To quantify the contribution of these interactions to the dynamical and statistical characteristics of the nonlinear wave field of soliton turbulence we study properties of the spatial moments of the two-soliton solution of the Korteweg–de Vries (KdV) ...

Added: January 18, 2013

Zybin K., Il'yn A. S., Physics-Uspekhi 2016 Vol. 59 No. 12 P. 1241-1244

This paper reviews the statistical properties and calculates the velocity structure functions of flows produced by a large-scale random scaling force in the Burgers model. ...

Added: September 22, 2017

Zybin K., Sirota V. A., Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 2012 Vol. 85 No. 5

We develop a theory of turbulence based on the inviscid Navier-Stokes equation. We get a simple but exact stochastic solution (vortex filament model) which allows us to obtain a power law for velocity structure functions in the inertial range. Combining the model with the multifractal conjecture, we calculate the scaling exponents without using the extended ...

Added: October 20, 2014

O.N. Savina, Central European Astrophysical Bulletin 2015 Vol. 39 P. 83-90

Natural oscillations of the entire nonisothermal solar atmosphere are analysed. Such oscillations are probably related to the acoustic gravity wave. Analytical and numerical solutions describing acoustic gravity wave perturbations in the entire solar atmosphere are studied. Based on the model temperature profile, we find the spatio-temporal dependence for the linear acoustic gravity wave characteristics. The ...

Added: December 6, 2015

Zybin K., Sirota V. A., Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 2013 Vol. 88 No. 4

The appearance of vortex filaments, the power-law dependence of velocity and vorticity correlations and their multiscaling behavior are derived from the Navier-Stokes equation. This is possible due to interpretation of the Navier-Stokes equation as an equation with multiplicative noise and remarkable properties of random matrix products. ...

Added: October 20, 2014

Kolokolov I., Lebedev V., Журнал экспериментальной и теоретической физики 2024 Т. 165 № 1 С. 128-140

We examine fluctuations of vorticity excited by an external random force in two-dimensional fluid in the presence of a strong external shear flow. The problem is motivated by the analysis of big coherent vortices appearing as a consequence of the inverse energy cascade in a finite box at large Reynolds numbers. We develop the perturbation ...

Added: January 29, 2024

P.A. Bespalov, O.N. Savina, Geomagnetism and Aeronomy 2019 Vol. 59 No. 7 P. 885-889

The preconditions for the formation of electron temperature jumps with scales comparable to the mean free path of electrons in the solar atmosphere are examined. In regions with heat flux, noise electric fields can arise due to ion-acoustic plasma turbulence. The well-known experimental data on heat flux from the corona to the chromosphere are used ...

Added: October 26, 2019

Sadykov V. M., Kosovichev A. G., Sharykin I.N. et al., Astrophysical Journal 2019 Vol. 871 No. 1, article id. 2 P. 1-13

We present a statistical study of chromospheric evaporation in solar flares using simultaneous observations by the RHESSI X-ray telescope and the Interface Region Imaging Spectrograph UV spectrograph. The results are compared with radiation hydrodynamic flare models from the F-CHROMA RADYN database. For each event, we study spatially resolved Doppler shifts of spectral lines formed in ...

Added: February 1, 2020

Parfenyev V., Vointsev I., Skoba A. et al., Physics of Fluids 2021 Vol. 33 No. 6 P. 1-11

Strong rotation makes an underlying turbulent flow quasi-two-dimensional that leads to the upscale energy transfer. Recent numerical simulations show that under certain conditions, the energy is accumulated at the largest scales of the system, forming coherent vortex structures known as condensates. We analytically describe the interaction of a strong condensate with weak small-scale turbulent pulsations ...

Added: June 15, 2021

Kolokolov I., Gamba A., Journal of Statistical Physics 1999 Vol. 94 No. 5/6 P. 759-777

We compute analytically the probability distribution function PP(ε) of the dissipation field ε=(∇θ)2 of a passive scalar θ advected by a d-dimensional random flow, in the limit of large Peclet and Prandtl numbers (Batchelor–Kraichnan regime). The tail of the distribution is a stretched exponential: for ε→∞, ln PP(ε)∼−(d2ε)1/3. ...

Added: March 5, 2017

Parfenyev V., Vergeles S. S., Physics of Fluids 2021 Vol. 33 No. 11 Article 115128

In the presence of strong background rotation, the velocity field tends to become quasi-two-dimensional, which leads to the inverse energy cascade. If the damping is small enough, then the energy is accumulated at the largest scales of the system, forming coherent columnar vortex structures known as condensates. Recently, it was found that the radial velocity ...

Added: November 19, 2021

Kolokolov I., Kostenko M., Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 2020 Vol. 101 No. 033108 P. 1-3

We consider two-dimensional turbulence in the presence of a condensate. The nondiagonal correlation
functions of the Lagrangian accelerations are calculated, and it is shown that they have the same universality
properties as the nondiagonal correlation functions of the velocity fluctuations. ...

Added: March 25, 2020

Savina O. N., Bespalov P. A., Central European Astrophysical Bulletin 2013 Vol. 37 No. 2 P. 507-512

Peculiarities of acoustic-gravity wave near the solar atmosphere transition region are analysed. An investigation is based on an original characteristic relation of waves in a two layers model with a temperature jump. Special attention is paid to an analysis of the properties of the surface waves, generated by the source of mass, which crosses the ...

Added: September 25, 2013

49606783, Mathematical notes 2017 Vol. 102 No. 2 P. 234-251

It is shown in the paper that the number pN(M) of partitions of a positive integer M
into N positive integer summands coincides with the Bose and Fermi distributions with logarithmic
accuracy if one identifies M with energy and N with the number of particles. We use the Gentile
statistics (a.k.a. parastatistics) to derive self-consistent algebraic equations that ...

Added: October 29, 2018

Kolokolov I., Lebedev V., Physical Review E - Statistical, Nonlinear, and Soft Matter Physics 2020 Vol. 102 No. 2 P. 1-5

We examine coherent vortices appearing as a result of the inverse cascade of two-dimensional turbulence in a
finite box in the case of pumping with arbitrary correlation time in the quasilinear regime. We demonstrate that
the existence of the vortices depends on the ratio between the values of the bottom friction coefficient α and the
viscous damping of ...

Added: October 6, 2020

Savina O.N., Bespalov P.A., Central European Astrophysical Bulletin 2016 Vol. 40 No. 1 P. 1-8

Some new features of the acoustic-gravity wave propagation from the sources at the photospheric heights through a nonisothermic solar chromosphere are examined. Within the framework of the plane-layered model of the atmosphere some properties of the wave perturbations near the height at which the horizontal phase wave velocity coincides with the local sound velocity are ...

Added: January 30, 2017

Kolokolov I., JETP Letters 2000 Vol. 71 No. 1 P. 12-14

Leading terms of the asymptotic behavior of the pair and higher order correlation functions for finite times and large distances have been calculated for the Burgers equation involving thermal noise. It is shown that an intermittence phenomenon occurs, whereby certain correlation functions are much greater than their reducible parts. ...

Added: March 5, 2017

Ilyin A., Kopyev A. V., Sirota V. A. et al., Physics of Fluids 2021 Vol. 33 No. 7 P. 075105-1-075105-10

Kinematic dynamo in incompressible isotropic turbulent flows with high magnetic Prandtl number is considered. The approach interpreting an arbitrary magnetic field distribution as a superposition of localized perturbations (blobs) is developed. We derive a general relation between stochastic properties of an isolated blob and a stochastically homogenous distribution of magnetic field advected by the same ...

Added: July 20, 2021