Stability of Parker's Steady Solar Wind Solution in the Subcritical Region

Parker’s steady solar wind solution (PSSWS) is a physically acceptable solution describing a smooth acceleration of the solar wind to supersonic speeds. Parker proposed that PSSWS possesses an intrinsic stability, like a “stable attractor” of this dynamical system. With a view to give a systematic a...

Full description

Bibliographic Details
Main Author: Bhimsen K. Shivamoggi
Format: Article
Language:English
Published: IOP Publishing 2023-01-01
Series:The Astrophysical Journal
Subjects:
Online Access:https://doi.org/10.3847/1538-4357/acb537
_version_ 1797702031208611840
author Bhimsen K. Shivamoggi
author_facet Bhimsen K. Shivamoggi
author_sort Bhimsen K. Shivamoggi
collection DOAJ
description Parker’s steady solar wind solution (PSSWS) is a physically acceptable solution describing a smooth acceleration of the solar wind to supersonic speeds. Parker proposed that PSSWS possesses an intrinsic stability, like a “stable attractor” of this dynamical system. With a view to give a systematic analytical development, we restrict ourselves to the subcritical region inside the Parker critical point (PCP) where the solar wind goes through sonic flow conditions. This enables one to avoid the singularity at PCP plaguing the linear stability problem. Following Parker, we approximate the corona in the subcritical region by a static atmosphere and amend it to include an azimuthal flow and a weak radial flow. These physical simplifications enable us to pose a Sturm–Liouville problem for linearized perturbations about PSSWS. PSSWS is shown to have an intrinsic stability in the subcritical region, while leaving the solar coronal base in a state of (1) rest, (2) corotation with the Sun, and (3) slow radial motion. This result is also shown to hold when a diabatic flow in near-isothermal conditions is included in Parker’s model to explicitly account for the extended coronal heating. The isothermal gas assumption in Parker’s model is then relaxed, and a more realistic barotropic fluid representing variable extended active coronal heating conditions is considered for the gas flow. The stability of PSSWS, as the solar wind flow emerges from a state of rest at the solar surface, is shown to continue to hold.
first_indexed 2024-03-12T04:45:20Z
format Article
id doaj.art-bda2eba6bc7d49e8869353c75611e3ae
institution Directory Open Access Journal
issn 1538-4357
language English
last_indexed 2024-03-12T04:45:20Z
publishDate 2023-01-01
publisher IOP Publishing
record_format Article
series The Astrophysical Journal
spelling doaj.art-bda2eba6bc7d49e8869353c75611e3ae2023-09-03T09:29:32ZengIOP PublishingThe Astrophysical Journal1538-43572023-01-0194419610.3847/1538-4357/acb537Stability of Parker's Steady Solar Wind Solution in the Subcritical RegionBhimsen K. Shivamoggi0Departments of Mathematics and Physics, University of Central Florida, Orlando, FL 32816-1364, USA ; bhimsen.shivamoggi@ucf.eduParker’s steady solar wind solution (PSSWS) is a physically acceptable solution describing a smooth acceleration of the solar wind to supersonic speeds. Parker proposed that PSSWS possesses an intrinsic stability, like a “stable attractor” of this dynamical system. With a view to give a systematic analytical development, we restrict ourselves to the subcritical region inside the Parker critical point (PCP) where the solar wind goes through sonic flow conditions. This enables one to avoid the singularity at PCP plaguing the linear stability problem. Following Parker, we approximate the corona in the subcritical region by a static atmosphere and amend it to include an azimuthal flow and a weak radial flow. These physical simplifications enable us to pose a Sturm–Liouville problem for linearized perturbations about PSSWS. PSSWS is shown to have an intrinsic stability in the subcritical region, while leaving the solar coronal base in a state of (1) rest, (2) corotation with the Sun, and (3) slow radial motion. This result is also shown to hold when a diabatic flow in near-isothermal conditions is included in Parker’s model to explicitly account for the extended coronal heating. The isothermal gas assumption in Parker’s model is then relaxed, and a more realistic barotropic fluid representing variable extended active coronal heating conditions is considered for the gas flow. The stability of PSSWS, as the solar wind flow emerges from a state of rest at the solar surface, is shown to continue to hold.https://doi.org/10.3847/1538-4357/acb537Solar wind
spellingShingle Bhimsen K. Shivamoggi
Stability of Parker's Steady Solar Wind Solution in the Subcritical Region
The Astrophysical Journal
Solar wind
title Stability of Parker's Steady Solar Wind Solution in the Subcritical Region
title_full Stability of Parker's Steady Solar Wind Solution in the Subcritical Region
title_fullStr Stability of Parker's Steady Solar Wind Solution in the Subcritical Region
title_full_unstemmed Stability of Parker's Steady Solar Wind Solution in the Subcritical Region
title_short Stability of Parker's Steady Solar Wind Solution in the Subcritical Region
title_sort stability of parker s steady solar wind solution in the subcritical region
topic Solar wind
url https://doi.org/10.3847/1538-4357/acb537
work_keys_str_mv AT bhimsenkshivamoggi stabilityofparkerssteadysolarwindsolutioninthesubcriticalregion