Solar Radio Burst Pairs Reveal Coronal Plasma Dynamics and Turbulent Echo Effects
Researchers detected spike-like repeating radio burst pairs in the solar corona at 30-50 MHz frequencies, characterized by two short-lived components separated by about 4 seconds. Analysis of 613 burst pairs using high-resolution imaging linked the sources to active regions and suggested the delayed bursts are turbulent echoes of harmonic emission in anisotropic coronal plasma. These findings advance understanding of coronal turbulence and magnetic reconnection processes occurring high in the solar atmosphere.
A new study published on arXiv reports the detection of distinctive spike-like repeating radio burst pairs in the solar corona using imaging spectroscopy techniques. The bursts consist of two short-lived (0.1-2 second), narrowband components separated by approximately 4 seconds at frequencies between 30-50 MHz. Researchers analyzed 613 burst pairs, measuring their durations, bandwidths, drift rates, flux densities, and spatial characteristics using high-resolution dynamic spectra and spectroscopic imaging. The imaging data linked burst sources to active regions, with earlier components concentrated above the region while delayed components were spatially displaced and showed reduced drift rates. Radio-wave propagation simulations supported the interpretation that delayed bursts represent turbulent echoes of harmonic emission in anisotropic coronal plasma. The high coronal location of burst sources suggests ongoing magnetic reconnection and electron acceleration well above typical flare heights, offering new insights into coronal turbulence and plasma diagnostics.
What's missing
The study does not discuss potential implications for space weather prediction or impacts on Earth-based radio communications, nor does it address how these findings compare to or integrate with existing models of solar radio burst generation mechanisms.
What different sources said
- arXiv astro-phCenter
Phase-drifting with emitting plasma temperature in the quasi-periodic pulsations of an X-class solar flare
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