Scholarlink

<p>The origin and maintenance of turbulence in the solar corona remain a fundamental problem in space plasma physics. Parametric Decay Instability (PDI) as a potential mechanism for generating turbulence in an open leakage-permitting vertical coronal domain is investigated using PLUTO, magnetohydrodynamics (MHD) code. We simulate the evolution of an Alfvén wave driven by a localized broadband (0.07 – 0.71 Hz) Hermite-Gaussian envelope in a plasma of <InlineEquation ID="IEq1"> <EquationSource Format="MATHML"><math> <mi>β</mi> <mo>=</mo> <mn>0.3</mn> </math></EquationSource> <EquationSource Format="TEX">$\beta = 0.3$</EquationSource> </InlineEquation>. PDI signatures emerge around <InlineEquation ID="IEq2"> <EquationSource Format="MATHML"><math> <mi>t</mi> <mo>≈</mo> <mn>20</mn> </math></EquationSource> <EquationSource Format="TEX">$t\approx 20$</EquationSource> </InlineEquation> simulation units, with backward-propagating Alfvén waves growing exponentially alongside compressive (acoustic) fluctuations. Backward-to-forward Alfvén wave ratios approach unity, and compressive amplitudes become comparable to the transverse components, indicating efficient nonlinear energy transfer. Spectral analysis reveals a <InlineEquation ID="IEq3"> <EquationSource Format="MATHML"><math> <msup> <mi>k</mi> <mrow> <mo>−</mo> <mn>2</mn> </mrow> </msup> </math></EquationSource> <EquationSource Format="TEX">$k^{-2}$</EquationSource> </InlineEquation> power law over a finite range, characteristic of a weak-MHD-like turbulence cascade, while increment Probability Distribution Functions yield non-Gaussian kurtosis, <InlineEquation ID="IEq4"> <EquationSource Format="MATHML"><math> <mi>K</mi> <mo>∈</mo> </math></EquationSource> <EquationSource Format="TEX">$K\in $</EquationSource> </InlineEquation> 6 - 10, signalling the onset of a weak, intermittent MHD-like turbulent state in this 2.5D configuration.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Parametric Decay Instability as a Source of Turbulence in an Open Leakage Permitting Vertical Solar Coronal Domain

  • 期刊论文

  • 发表日期：

    2026年6月2日

查看全文
  • Bivek Pradhan,
  • Utpal Deka

摘要

The origin and maintenance of turbulence in the solar corona remain a fundamental problem in space plasma physics. Parametric Decay Instability (PDI) as a potential mechanism for generating turbulence in an open leakage-permitting vertical coronal domain is investigated using PLUTO, magnetohydrodynamics (MHD) code. We simulate the evolution of an Alfvén wave driven by a localized broadband (0.07 – 0.71 Hz) Hermite-Gaussian envelope in a plasma of β = 0.3 $\beta = 0.3$ . PDI signatures emerge around t ≈ 20 $t\approx 20$ simulation units, with backward-propagating Alfvén waves growing exponentially alongside compressive (acoustic) fluctuations. Backward-to-forward Alfvén wave ratios approach unity, and compressive amplitudes become comparable to the transverse components, indicating efficient nonlinear energy transfer. Spectral analysis reveals a k − 2 $k^{-2}$ power law over a finite range, characteristic of a weak-MHD-like turbulence cascade, while increment Probability Distribution Functions yield non-Gaussian kurtosis, K ∈ $K\in $ 6 - 10, signalling the onset of a weak, intermittent MHD-like turbulent state in this 2.5D configuration.