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## Collective processes in the transition region of the solar atmosphere

Central European Astrophysical Bulletin. 2015. Vol. 39. P. 43–50.

Bespalov P. A., Savina O.N.

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 threshold of ion-acoustic instability in the transition

region. A characteristic value of the electric field in ion-acoustic turbulence is estimated.

Priority areas:
mathematics

Language:
English

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

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

Ruderman M.., Petrukhin N., Astronomy and Astrophysics 2017 Vol. 600 No. A122 P. 1–11

The ability of phase mixing to provide eﬃcient damping of Alfvén waves even in weakly dissipative plasmas made it a popular mechanismforexplainingthesolarcoronalheating.Initiallyitwasstudiedintheequilibriumconﬁgurationswiththestraightmagnetic ﬁeldlinesandtheAlfvénspeedonlyvaryinginthedirectionperpendiculartothemagneticﬁeld.LatertheanalysisoftheAlfvénwave phase mixing was extended in various directions. In particular it was studied in two-dimensional planar magnetic plasma equilibria. Analytical investigation was carried out under the assumption that the wavelength is much smaller ...

Added: May 10, 2017

Efremov V. I., Solov'ev A. A., Parfinenko L. D. et al., Astrophysics and Space Science 2018 Vol. 363 No. 61 P. 1–14

A specific type of artifacts (named as “p2p”), that originate due to displacement of the image of a moving
object along the digital (pixel) matrix of receiver are analyzed in detail. The criteria of appearance and the influence
of these artifacts on the study of long-term oscillations of sunspots are deduced. The obtained criteria suggest us methods for reduction or even ...

Added: March 4, 2018

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

П.А. Беспалов, О.Н. Савина, 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 ...

Added: June 4, 2015

Litvinenko G. V., V. E. Shaposhnikov, Konovalenko A. A. et al., Icarus 2016 Vol. 272 P. 80–87

We investigate the dynamic spectra of the Sun and Jovian decametric radiation obtained by the authors with the radio telescopes UTR-2 and URAN-2 (Kharkov, Poltava, Ukraine). We focus on the similar structures that appear on the dynamic spectra of those objects: S-bursts, drifting pairs, absorption bursts and zebra patterns. Similarity in structures allows us to ...

Added: February 29, 2016

Bespalov P. A., Savina O. N., Monthly Notices of the Royal Astronomical Society 2007 Vol. 382 No. 1 P. L63–L66

In this Letter, the generalized Wiedemann-Franz law for the non-isothermic quasi-neutral plasma with developed ion-acoustic turbulence is proved. This law determines the relationship between electrical and thermal conductivities in a plasma with well-developed ion-acoustic turbulence. The anomalously low thermal conductivity, which leads to the formation of high temperature gradients in the zone of the temperature ...

Added: December 12, 2012

Ruderman M. S., Petrukhin N., Pelinovsky E., Solar Physics 2021 Vol. 296 Article 124

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 ...

Added: August 18, 2021

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

Bakunina I. A., Melnikov V. F., Morgachev A. S., Geomagnetism and Aeronomy 2020 Vol. 60 No. 7 P. 853–859

The spatial dynamics of microwave emission (data from the Nobeyama Radioheliograph) of activeregions with a complex magnetic field configuration before powerful f lares, as well as the fine structure ofactive sources of ultraviolet (UV) emission based on AIA/SDO data, are studied. It is shown that there isunsteady behavior of microwave sources, along with the ignition ...

Added: January 18, 2021

I.A. Bakunina, Melnikov V. F., Astronomical and Astrophysical Transactions 2019 Vol. 31 No. 3 P. 251–266

In this paper, we describe the spatial structure and time characteristics of the microwave emission of active region AR 12673 during the rapid changes in the magnetic
ux from September 3 to September 6, 2017 using Nobeyama Radioheliograph observations. It is shown that the microwave emission of the active region exhibits extremely
non-stationary behavior of both spatial ...

Added: October 31, 2019

Abramov-Maximov V. E., Bakunina I. A., Geomagnetism and Aeronomy 2020 Vol. 60 No. 7 P. 846–852

A study of quasi-periodic fluctuations of solar microwave emission at the pref lare stage is pre-sented. Data from daily solar observations by the Nobeyama Radioheliograph at a frequency of 17 GHz areused. Five f lares are analyzed based on synthesized two-dimensional radio images. All of the consideredevents are characterized by pref lare fluctuations of microwave emission ...

Added: January 18, 2021

Melnikov V. F., Morgachev A. S., Bakunina I. A., Astrophysics, Springer Nature Switzerland AG. Part of Springer Nature 2020 Vol. 63 No. 2 P. 252–259

This paper is a study of the spatial dynamics of microwave emission (data from the Nobeyama Radioheliograph) from two active regions NOAA 12673 and NOAA 11261 for several hours prior to powerful class M x-ray flares. The spatial distribution of the radio brightness and emission intensity in certain parts of the active region is found ...

Added: June 25, 2020

Irina A. Bakunina, Abramov-Maximov V., Nakariakov V. et al., Publications of the Astronomical Society of Japan 2013 Vol. 65 No. SP1 P. S13-1–S13-12

Long-term oscillations of microwave emission generated in sunspot magnetospheres are detected with the Nobeyama Radioheliograph (NoRH) at a frequency of 17 GHz, and the Siberian Solar Radio Telescope (SSRT) at 5.7 GHz. Significant periodicities in the range of 22–170 min are found in the variation of the emission intensity, polarisation and the degree of circular polarisation. Periods of ...

Added: December 30, 2013

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

СПб.: Главная (Пулковская) астрономическая обсерватория РАН, 2020

Сборник содержит доклады, представленные на XXIV Всероссийскую ежегодную конференцию по физике Солнца «Солнечная и солнечно-земная физика – 2020» (5 – 9 октября 2020, ГАО РАН, Санкт-Петербург). Конференция проводилась Главной (Пулковской) астрономической обсерваторией РАН при поддержке секции «Солнце» Научного совета по астрономии РАН и секции «Плазменные процессы в магнитосферах планет, атмосферах Солнца и звёзд» Научного совета ...

Added: January 18, 2021

Буров А.А., Герман А. Д., Косенко И. И., Космические исследования 2014 Т. 52 № 4 С. 307–312

The problem of planar oscillations of a pendulum with variable length suspended on the Moon’s surface is considered. It is assumed that the Earth and Moon (or, in the general case, a planet and its satellite, or an asteroid and a spacecraft) revolve around the common center of mass in unperturbed elliptical Keplerian orbits. We ...

Added: November 8, 2014

Пенза: ПГУ, 2015

В сборник трудов включены доклады юбилейного ХХ-го Международного симпозиума «Надежность и качество», проходившего с 25 по 31 мая 2015 г. в городе Пензе.
Рассмотрены актуальные проблемы теории и практики повышения надежности и качества; эффективности внедрения инновационных и информационных технологий в фундаментальных научных и прикладных исследованиях, образовательных и коммуникативных системах и средах, экономике и юриспруденции; методов и ...

Added: May 31, 2015

BOSSY M., Jabir J. M., Electronic Communications in Probability 2018 Vol. 23 P. 1–14

In this paper, we prove a particle approximation, in the sense of the propagation of chaos, of a Lagrangian stochastic model submitted to specular boundary condition and satisfying the mean no-permeability condition. ...

Added: June 7, 2018

Arseyev P., Mantsevich V. N., Maslova N. S., JETP Letters 2011 Vol. 94 No. 5 P. 422–428

We present theoretical investigation of spatial charge distribution in the two-level system with strong Coulomb correlations by means of Heisenberg equations analysis for localized states total electron filling numbers taking into account pair correlations of local electron density. It was found that tunneling current through nanometer scale structure with strongly coupled localized states causes Coulomb ...

Added: October 28, 2014

Min Namkung, Younghun K., Scientific Reports 2018 Vol. 8 No. 1 P. 16915-1–16915-18

Sequential state discrimination is a strategy for quantum state discrimination of a sender’s quantum
states when N receivers are separately located. In this report, we propose optical designs that can
perform sequential state discrimination of two coherent states. For this purpose, we consider not
only binary phase-shifting-key (BPSK) signals but also general coherent states, with arbitrary prior
probabilities. Since ...

Added: November 16, 2020

Belavin V., Geiko R., Journal of High Energy Physics 2017 Vol. 125 P. 1–13

We continue to investigate the dual description of the Virasoro conformal blocks arising in the framework of the classical limit of the AdS3/CFT2 correspondence. To give such an interpretation in previous studies, certain restrictions were necessary. Our goal here is to consider a more general situation available through the worldline approximation to the dual AdS gravity. ...

Added: August 31, 2017

Akhmedov E., Physical Review D - Particles, Fields, Gravitation and Cosmology 2013 Vol. 87 No. 4 P. 044049

Following Krotov and Polyakov [ Nucl. Phys. B849 410 (2011)], we show that in global de Sitter space its isometry is broken by the loop IR divergences for any invariant vacuum state of the massive scalars. We derive a kinetic equation in global de Sitter space that follows from the Dyson-Schwinger equation of the Schwinger-Keldysh ...

Added: February 27, 2013