Solar Vortices Found to Enhance Magnetoacoustic Wave Dissipation and Atmospheric Heating
A new study using high-resolution 3D radiative MHD simulations finds that photospheric vortex flows amplify slow magnetoacoustic wave energy dissipation and raise temperatures in the solar chromosphere. The research tracked magnetic field lines to show that slow-mode waves steepen into shocks as they travel upward through the stratified solar atmosphere, with vortex regions exhibiting systematically higher temperatures than non-vortex regions. The findings help clarify a long-standing question in solar physics about how energy is transported from the photosphere to heat the chromosphere.
Researchers have used three-dimensional radiative magnetohydrodynamic (MHD) simulations to investigate how photospheric vortex flows influence the propagation and dissipation of slow magnetoacoustic waves in the solar atmosphere. Field-line tracking revealed that upward-propagating slow-mode waves amplify as they travel through the stratified atmosphere and steepen into shocks upon reaching the chromosphere, generating recurrent plasma surges with characteristic shock signatures. Vortex structures were identified using a swirling strength diagnostic with height-dependent Gaussian smoothing to account for their expanding geometry with altitude. Comparing vortex and non-vortex field lines, the study found systematically enhanced temperatures in vortex regions, while the height at which shocks form showed no significant difference between the two, indicating that rotational flows do not alter shock formation altitude. However, supersonic upflows in vortex regions displayed somewhat higher parallel velocities, suggesting vortex-driven motions amplify shock propagation speeds. The results, accepted in Frontiers in Astronomy and Space Sciences, highlight the coupled role of slow-mode shocks and vortex flows in chromospheric energy transport and thermal structuring of the lower solar atmosphere.
What's missing
The paper also does not quantify the absolute contribution of vortex-driven dissipation relative to other proposed chromospheric heating mechanisms such as Alfvén wave dissipation or reconnection events.
What different sources said
- arXiv astro-phCenter
Solar Vortices: Catalysts of Magnetoacoustic Wave Dissipation and Atmospheric Heating
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