Dispersion of Slow Magnetoacoustic Waves in the Active Region Fan Loops Introduced by Thermal Misbalance

Abstract

Slow magnetoacoustic waves observed in the solar corona are used as seismological probes of plasma parameters. It has been shown that dispersion properties of such waves can vary significantly under the influence of the wave-induced thermal misbalance. In the current research, we study the effect of misbalance on waves inside the magnetic-flux tube under the second-order thin-flux-tube approximation. Using the parameters of active region fan coronal loops, we calculated wave properties such as the phase speed and decrement. It is shown that neglecting thermal misbalance may be the reason for the substantial divergence between seismological and spectrometric estimations of plasma parameters. We also show that the frequency dependence of phase speed is affected by two features, namely the geometric dispersion and the dispersion caused by the thermal misbalance. In contrast to the phase speed, the wave decrement primarily is affected by the thermal misbalance only. The dependencies of the phase speed and decrement of the slow wave on magnetic field and tube cross-section are also analyzed.

References in corpus (16)

• CHIANTI -- an atomic database for emission lines -- Paper XVI: Version 10, further extensions
• Standing Slow-Mode Waves in Hot Coronal Loops: Observations, Modeling, and Coronal Seismology
• Solar coronal magnetic fields derived using seismology techniques applied to omnipresent sunspot waves
• 3D Coronal Slow Modes: Towards 3D Seismology
• Formation of quasi-periodic slow magnetoacoustic wave trains by the heating/cooling misbalance
• Frequency-dependent damping in propagating slow magneto-acoustic waves
• 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
• Accelerating waves in polar coronal holes as seen by EIS and SUMER
• The polytropic index of solar coronal plasma in sunspot fan loops and its temperature dependence
• Plasma sloshing in pulse-heated solar and stellar coronal loops
• The effect of magnetic field on the damping of slow waves in the solar corona
• Observed damping of the slow magnetoacoustic mode
• Mixed properties of slow magnetoacoustic and entropy waves in a plasma with heating/cooling misbalance
• Effect of Thermal Conductivity, Compressive Viscosity and Radiative Cooling on the Phase Shift of Propagating Slow Waves with and without Heating-Cooling Imbalance
• First Imaging Observation of Standing Slow Wave in Coronal Fan loops

Cited by in corpus (5)

• The solar corona as an active medium for magnetoacoustic waves
• A new look at the frequency-dependent damping of slow-mode waves in the solar corona
• Dynamics of fast and slow magnetoacoustic waves in plasma slabs with thermal misbalance
• Exact solution to the problem of slow oscillations in coronal loops and its diagnostic applications
• The effect of thermal misbalance on magnetohydrodynamic modes in coronal magnetic cylinders