Effect of transport coefficients on excitation of flare-induced standing slow-mode waves in coronal loops

Abstract

Standing slow-mode waves have been recently observed in flaring loops by the Atmospheric Imaging Assembly (AIA) of the Solar Dynamics Observatory (SDO). By means of the coronal seismology technique transport coefficients in hot ($\sim$10 MK) plasma were determined by Wang et al.(2015, Paper I), revealing that thermal conductivity is nearly suppressed and compressive viscosity is enhanced by more than an order of magnitude. In this study we use 1D nonlinear MHD simulations to validate the predicted results from the linear theory and investigate the standing slow-mode wave excitation mechanism. We first explore the wave trigger based on the magnetic field extrapolation and flare emission features. Using a flow pulse driven at one footpoint we simulate the wave excitation in two types of loop models: model 1 with the classical transport coefficients and model 2 with the seismology-determined transport coefficients. We find that model 2 can form the standing wave pattern (within about one period) from initial propagating disturbances much faster than model 1, in better agreement with the observations. Simulations of the harmonic waves and the Fourier decomposition analysis show that the scaling law between damping time ($\tau$) and wave period ($P$) follows $\tau \propto P^2$ in model 2, while $\tau \propto P$ in model 1. This indicates that the largely enhanced viscosity efficiently increases the dissipation of higher harmonic components, favoring the quick formation of the fundamental standing mode. Our study suggests that observational constraints on the transport coefficients are important in understanding both, the wave excitation and damping mechanisms.

19 pages, 17 figures,2 tables, 1 animation; accepted by ApJ

References in corpus (23)

• Optimization code with weighting function for the reconstruction of coronal magnetic fields
• Preprocessing of vector magnetograph data for a non-linear force-free magnetic field reconstruction
• Non-linear force-free field modeling of a solar active region around the time of a major flare and coronal mass ejection
• Solar coronal magnetic fields derived using seismology techniques applied to omnipresent sunspot waves
• Determination of the Coronal Magnetic Field by Hot Loop Oscillations
• The Influence of Spatial Resolution on Nonlinear Force-Free Modeling
• Evidence of thermal conduction suppression in a solar flaring loop by coronal seismology of slow-mode waves
• X-ray and EUV Observations of Simultaneous Short and Long Period Oscillations in Hot Coronal Arcade Loops
• Combined Modeling of Acceleration, Transport, and Hydrodynamic Response in Solar Flares: I. The Numerical Model
• SDO/AIA Observations of a Reflecting Longitudinal Wave in a Coronal Loop
• Forward Modelling of Standing Slow Modes in Flaring Coronal Loops
• Suppression of parallel transport in turbulent magnetized plasmas and its impact on non-thermal and thermal aspects of solar flares
• Modelling of Reflective Propagating Slow-mode Wave in a Flaring Loop
• Long Duration Flare Emission: Impulsive or Gradual Heating?
• Effect of a Radiation Cooling and Heating Function on Standing Longitudinal Oscillations in Coronal Loops
• Multi-instrument observations of a failed flare eruption associated with MHD waves in a loop bundle
• Reflection Of Propagating Slow Magneto-acoustic Waves In Hot Coronal Loops : Multi-instrument Observations and Numerical Modelling
• Two-Phase Heating in Flaring Loops
• Anomalous Cooling of Coronal Loops with Turbulent Suppression of Thermal Conduction
• Heating and cooling of coronal loops with turbulent suppression of parallel heat conduction
• First Imaging Observation of Standing Slow Wave in Coronal Fan loops
• Plasma Heating to Super-Hot Temperatures (>30 MK) in the August 9, 2011 Solar Flare
• Excitation of flare-induced waves in coronal loops and the effects of radiative cooling

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• Damping of slow magnetoacoustic oscillations by the misbalance between heating and cooling processes in the solar corona
• Seismological constraints on the solar coronal heating function
• The polytropic index of solar coronal plasma in sunspot fan loops and its temperature dependence
• Mixed properties of slow magnetoacoustic and entropy waves in a plasma with heating/cooling misbalance
• Large-amplitude quasi-periodic pulsations as evidence of impulsive heating in hot transient loop systems detected in the EUV with SDO/AIA
• Role of Compressive Viscosity and Thermal Conductivity on the Damping of Slow Waves in the Coronal Loops With and Without Heating-Cooling Imbalance
• Determination of transport coefficients by coronal seismology of flare-induced slow-mode waves: Numerical parametric study of 1D loop model
• Effect of Thermal Conductivity, Compressive Viscosity and Radiative Cooling on the Phase Shift of Propagating Slow Waves with and without Heating-Cooling Imbalance
• Excitation and Damping of Slow Magnetosonic Waves in Flaring Hot Coronal Loops: Effects of Compressive Viscosity
• Role of Non-Ideal Dissipation with Heating-Cooling Misbalance on the Phase Shifts of Standing Slow Magnetohydrodynamic Waves
• A new look at the frequency-dependent damping of slow-mode waves in the solar corona
• Coronal seismology by slow waves in non-adiabatic conditions
• Compressive oscillations in hot coronal loops: Are sloshing oscillations and standing slow waves independent?
• Plasma heating and nanoflare caused by slow-mode wave in a coronal loop
• Non-local thermal transport impact on compressive waves in two-temperature coronal loops
• The effect of thermal misbalance on magnetohydrodynamic modes in coronal magnetic cylinders
• Exploring Standing and Reflected Slow-mode Waves in Flaring Coronal Loops: A Parametric Study Using 2.5D MHD Modeling
• The Temperature-dependent Damping of Propagating Slow Magnetoacoustic Waves