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VLA observations of the quiet Sun at 20 cm wavelength show bright, evolving loops that lie above individual active regions, while observations at 91 cm often outline fainter, extended loops that appear to join widely-separated active regions on the solar surface. Observations at 91 cm also reveal intense noise storms which lie along extended structures above the 20 cm loops. The source of the noise storm continuum is thought to be due to the plasma turbulence that results when electrons are injected into lower-lying loops. The accelerated particles may be produced as a consequence of magnetic reconnection of emerging flux with pre-existing magnetic fields. In this paper we compare VLA observations of active regions and noise storms at 20 and 91 cm with simultaneous images from the Soft X-ray Telescope aboard the Yohkoh satellite and with photospheric magnetograms from Kitt Peak. These data have been used to study correspondances between spatial and temporal variations of coronal loops, the emergence of magnetic flux and the onset of Type I noise storms. We also compare the structure of compact coronal loops at radio (20 cm) and X-ray wavelengths with coronal magnetic field extrapolations in order to examine whether non-potential, or current-amplified, magnetic fields play a role in shaping the corona above these active regions.
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