The temporal variations in the soft X-ray (SXR) emission and the radio emission above the solar magnetic network of the quiet corona have been investigated using Yohkoh SXR images with deep exposure and VLA observations in the centimetric radio range. The SXR data show several brightenings with an extrapolated occurrence probability of one brightening per 3 seconds on the total solar surface. During the roughly 10 minutes of enhanced flux, the total radiative losses of the observed plasma are betwee () n 0.6 and 2.4 cdot 1026 erg per event. These events are more than an order of magnitude smaller than previously reported X-ray bright points or active region transient brightenings. For all of the four SXR events with simultaneous radio observations, a corresponding radio source correlating in space and time can be found. There are several similarities between these SXR/radio events and regular solar flares. These events thus appear to be flare-like and are called network flares. We will report also on very recent work using SOHO's EIT and CDS experiments combined with VLA and Kitt Peak observations.
IAU Joint Discussion
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