Abstract:
One of the most common assumptions in radio astronomy is that the continuum spectrum of
a radio source follows a simple power-law. Such an assumption is being challenged by the
data being produced by the new sophisticated megahertz-sensitive telescopes and broadband
gigahertz-receivers, as we can now sample the spectra of radio sources at a level of
detail never before achievable. We are finding that a power-law description is inappropriate
for many radio sources, particularly at low frequencies where absorption processes become
significant. I will outline in my talk how low-frequency absorption processes provides
us with a unique tool to test radio galaxy evolutionary models, mass loss scenarios of
progenitor stars to supernovae, particle acceleration processes in pulsar wind nebulae,
and a way to identify high-redshift galaxies. In particular, I will demonstrate that probing
these absorption processes opens up an untapped discovery space for exotic objects that
have been missed in more traditional spectral searches.
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