Modeling the Magnetic Field of the Inner Corona in a Radially Expanding Solar Wind

The magnetic field in the interplanetary medium is formed by the action of magnetic field sources on the photosphere of the Sun and currents in the expanding atmosphere of the Sun and the solar wind. In turn, the high-speed plasma flow changes the configuration of the magnetic field lines. The probl...

Full description

Bibliographic Details
Main Authors: Andrey G. Tlatov, Ivan Berezin
Format: Article
Language:English
Published: MDPI AG 2023-01-01
Series:Physics
Subjects:
Online Access:https://www.mdpi.com/2624-8174/5/1/12
_version_ 1797609441801011200
author Andrey G. Tlatov
Ivan Berezin
author_facet Andrey G. Tlatov
Ivan Berezin
author_sort Andrey G. Tlatov
collection DOAJ
description The magnetic field in the interplanetary medium is formed by the action of magnetic field sources on the photosphere of the Sun and currents in the expanding atmosphere of the Sun and the solar wind. In turn, the high-speed plasma flow changes the configuration of the magnetic field lines. The problem of determining the parameters of the magnetic field near the Sun is thus a three-dimensional problem of the interaction of the magnetic field and the plasma of the solar wind. We present analytical expressions for calculating the total magnetic field vector <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mover accent="true"><mi>B</mi><mo>→</mo></mover><mrow><mo>(</mo><mi>r</mi><mo>,</mo><mi> </mi><mi>θ</mi><mo>,</mo><mi> </mi><mi>ϕ</mi><mo>)</mo></mrow></mrow></semantics></math></inline-formula> (in spherical coordinates) for a radially expanding solar wind flow of finite conductivity. The parameters of the solar wind are given in the form of a dimensionless magnetic Reynolds number given as an arbitrary function of the radius, <i>r</i>: <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>R</mi><mi mathvariant="normal">m</mi></msub></semantics></math></inline-formula> = <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>r</mi><mi>σ</mi><mi>μ</mi><mi>v</mi><mo>=</mo><mi>ξ</mi><mo>(</mo><mi>r</mi><mo>)</mo></mrow></semantics></math></inline-formula>, where <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>σ</mi></semantics></math></inline-formula>, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>μ</mi></semantics></math></inline-formula>, and <i>v</i> denote, respectively, the conductivity, magnetic permeability, and velocity of the solar wind. The solution for the magnetic field components is obtained in the form of a decomposition in spherical functions and a radial part depending on the distance from the Sun. Examples of calculations of the configuration of magnetic fields and structures of the solar corona for the solar eclipse of 21 August 2017 are given.
first_indexed 2024-03-11T06:01:25Z
format Article
id doaj.art-97052190c24d4427b1fc9097b34004fd
institution Directory Open Access Journal
issn 2624-8174
language English
last_indexed 2024-03-11T06:01:25Z
publishDate 2023-01-01
publisher MDPI AG
record_format Article
series Physics
spelling doaj.art-97052190c24d4427b1fc9097b34004fd2023-11-17T13:20:15ZengMDPI AGPhysics2624-81742023-01-015116116710.3390/physics5010012Modeling the Magnetic Field of the Inner Corona in a Radially Expanding Solar WindAndrey G. Tlatov0Ivan Berezin1Kislovodsk Mountain Astronomical Station of the Pulkovo Observatory, Gagarina Str. 100, 357700 Kislovodsk, RussiaKislovodsk Mountain Astronomical Station of the Pulkovo Observatory, Gagarina Str. 100, 357700 Kislovodsk, RussiaThe magnetic field in the interplanetary medium is formed by the action of magnetic field sources on the photosphere of the Sun and currents in the expanding atmosphere of the Sun and the solar wind. In turn, the high-speed plasma flow changes the configuration of the magnetic field lines. The problem of determining the parameters of the magnetic field near the Sun is thus a three-dimensional problem of the interaction of the magnetic field and the plasma of the solar wind. We present analytical expressions for calculating the total magnetic field vector <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mover accent="true"><mi>B</mi><mo>→</mo></mover><mrow><mo>(</mo><mi>r</mi><mo>,</mo><mi> </mi><mi>θ</mi><mo>,</mo><mi> </mi><mi>ϕ</mi><mo>)</mo></mrow></mrow></semantics></math></inline-formula> (in spherical coordinates) for a radially expanding solar wind flow of finite conductivity. The parameters of the solar wind are given in the form of a dimensionless magnetic Reynolds number given as an arbitrary function of the radius, <i>r</i>: <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>R</mi><mi mathvariant="normal">m</mi></msub></semantics></math></inline-formula> = <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>r</mi><mi>σ</mi><mi>μ</mi><mi>v</mi><mo>=</mo><mi>ξ</mi><mo>(</mo><mi>r</mi><mo>)</mo></mrow></semantics></math></inline-formula>, where <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>σ</mi></semantics></math></inline-formula>, <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>μ</mi></semantics></math></inline-formula>, and <i>v</i> denote, respectively, the conductivity, magnetic permeability, and velocity of the solar wind. The solution for the magnetic field components is obtained in the form of a decomposition in spherical functions and a radial part depending on the distance from the Sun. Examples of calculations of the configuration of magnetic fields and structures of the solar corona for the solar eclipse of 21 August 2017 are given.https://www.mdpi.com/2624-8174/5/1/12solar windsolar coronasolar magnetic field model
spellingShingle Andrey G. Tlatov
Ivan Berezin
Modeling the Magnetic Field of the Inner Corona in a Radially Expanding Solar Wind
Physics
solar wind
solar corona
solar magnetic field model
title Modeling the Magnetic Field of the Inner Corona in a Radially Expanding Solar Wind
title_full Modeling the Magnetic Field of the Inner Corona in a Radially Expanding Solar Wind
title_fullStr Modeling the Magnetic Field of the Inner Corona in a Radially Expanding Solar Wind
title_full_unstemmed Modeling the Magnetic Field of the Inner Corona in a Radially Expanding Solar Wind
title_short Modeling the Magnetic Field of the Inner Corona in a Radially Expanding Solar Wind
title_sort modeling the magnetic field of the inner corona in a radially expanding solar wind
topic solar wind
solar corona
solar magnetic field model
url https://www.mdpi.com/2624-8174/5/1/12
work_keys_str_mv AT andreygtlatov modelingthemagneticfieldoftheinnercoronainaradiallyexpandingsolarwind
AT ivanberezin modelingthemagneticfieldoftheinnercoronainaradiallyexpandingsolarwind