A new look at the frequency-dependent damping of slow-mode waves in the solar corona

Abstract

Being directly observed in the Doppler shift and imaging data and indirectly as quasi-periodic pulsations in solar and stellar flares, slow magnetoacoustic waves offer an important seismological tool for probing many vital parameters of the coronal plasma. A recently understood active nature of the solar corona for magnetoacoustic waves, manifested through the phenomenon of wave-induced thermal misbalance, led to the identification of new natural mechanisms for the interpretation of observed properties of waves. A frequency-dependent damping of slow waves in various coronal plasma structures remains an open question, as traditional wave damping theories fail to match observations. We demonstrate that accounting for the back-reaction caused by thermal misbalance on the wave dynamics leads to a modification of the relationship between the damping time and oscillation period of standing slow waves, prescribed by the linear theory. The modified relationship is not of a power-law form and has the equilibrium plasma conditions and properties of the coronal heating/cooling processes as free parameters. It is shown to readily explain the observed scaling of the damping time with period of standing slow waves in hot coronal loops. Functional forms of the unknown coronal heating process, consistent with the observed frequency-dependent damping, are seismologically revealed.

Accepted for publication in MNRAS Lett

References in corpus (19)

• CHIANTI -- an atomic database for emission lines -- Paper XVI: Version 10, further extensions
• Coronal heating by MHD waves
• Quasi-periodic pulsations in solar and stellar flares: an overview of recent results
• Slow-Mode Magnetoacoustic Waves in Coronal Loops
• Determination of the Coronal Magnetic Field by Hot Loop Oscillations
• MHD Waves in open coronal structures
• Frequency-dependent damping in propagating slow magneto-acoustic waves
• X-ray and EUV Observations of Simultaneous Short and Long Period Oscillations in Hot Coronal Arcade Loops
• SDO/AIA Observations of a Reflecting Longitudinal Wave in a Coronal Loop
• Forward Modelling of Standing Slow Modes in Flaring Coronal Loops
• Plasma sloshing in pulse-heated solar and stellar coronal loops
• Observations of Dissipation of Slow Magneto-acoustic Waves in a Polar Coronal Hole
• The effect of magnetic field on the damping of slow waves in the solar corona
• Multi-instrument observations of a failed flare eruption associated with MHD waves in a loop bundle
• Dispersion of Slow Magnetoacoustic Waves in the Active Region Fan Loops Introduced by Thermal Misbalance
• 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
• Role of Non-Ideal Dissipation with Heating-Cooling Misbalance on the Phase Shifts of Standing Slow Magnetohydrodynamic Waves
• Unravelling the components of a multi-thermal coronal loop using magnetohydrodynamic seismology

Cited by in corpus (6)

• Two-fluid numerical model of chromospheric heating and plasma outflows in a quiet-Sun
• Exact solution to the problem of slow oscillations in coronal loops and its diagnostic applications
• Bayesian evidence for two slow-wave damping models in hot coronal loops
• Impact of thermal misbalance on acoustic-gravity waves in the solar atmosphere
• Exploring Standing and Reflected Slow-mode Waves in Flaring Coronal Loops: A Parametric Study Using 2.5D MHD Modeling
• The effect of thermal misbalance on magnetohydrodynamic modes in coronal magnetic cylinders