On the feasibility of imaging coronal mass ejections at radio wavelengths

Coronal mass ejections (CMEs) can have a profound impact on the interplanetary medium and the near-Earth environment. We discuss the feasibility of detecting coronal mass ejections at radio wavelengths with a ground-based instrument. In particular, we explore the possibility that a radio telescope employing Fourier synthesis imaging techniques can detect thermal bremsstrahlung emission from CMEs. Using a simulated database from such a telescope, we explore three detection schemes: direct detection, an approximate differential detection scheme, and an “exact” differential detection scheme. We conclude that thermal bremsstrahlung emission from CMEs can be detected by such a telescope provided differential techniques are employed. While the approximate differential detection scheme may be sufficient for CMEs viewed near the solar limb, detection of CMEs against the solar disk may require the more sensitive exact differential scheme. The detection and imaging of nonthermal radio emissions from CMEs is also discussed.

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