  The recent availability of fine grained high sensitivity data from the new
generation low radio frequency instruments such as the Murchison Widefield
Array (MWA) have opened up opportunities for using novel techniques for
characterizing the nature of solar emission at these frequencies. Here we use
this opportunity to look for evidence for the presence of weak non-thermal
emissions in the 100-240 MHz band, at levels weaker than have usually been
probed. The presence of such features is believed to be a necessary consequence
of nanoflare-based coronal and chromospheric heating theories. We separate the
calibrated MWA solar dynamic spectra into a slowly varying and an impulsive,
and hence non-thermal, component. We demonstrate that Gaussian mixtures
modeling can be used to robustly model the latter and we estimate the flux
density distribution as well as the prevalence of impulsive non-thermal
emission in the frequency-time plane. Evidence for presence of non-thermal
emission at levels down to $\sim$0.2 SFU (1 SFU = 10$^4$ Jy) is reported,
making them the weakest reported emissions of this nature. Our work shows the
fractional occupancy of the non-thermal impulsive emission to lie in the
17--45\% range during a period of medium solar activity. We also find that the
flux density radiated in the impulsive non-thermal emission is very similar in
strength to that of the slowly varying component, dominated by the thermal
bremsstrahlung. Such significant prevalence and strength of the weak impulsive
non-thermal emission has not been appreciated earlier.
