  Solar radio observations provide a unique diagnostic of the outer solar
atmosphere. However, the inhomogeneous turbulent corona strongly affects the
propagation of the emitted radio waves, so decoupling the intrinsic properties
of the emitting source from the effects of radio-wave propagation has long been
a major challenge in solar physics. Here we report quantitative spatial and
frequency characterization of solar radio burst fine structures observed with
the LOw Frequency Array (LOFAR), an instrument with high time resolution that
also permits imaging at scales much shorter than those corresponding to
radio-wave propagation in the corona. The observations demonstrate that
radio-wave propagation effects, and not the properties of the intrinsic
emission source, dominate the observed spatial characteristics of radio burst
images. These results permit more accurate estimates of source brightness
temperatures, and open opportunities for quantitative study of the mechanisms
that create the turbulent coronal medium through which the emitted radiation
propagates.
