invisible Plasma?

[SeRDaRr]

I read in the web
"A plasma can in principle never be completely dark because there
will
be radiation emitted as the protons and electrons recombine. However,
if the plasma is so dense and energetic that no individual atoms can
form (like in the interior of the sun), then there won't be any
recombination and radiation"
<snip> ".... in this sense it is well possible that a large plasma
mass at the center of galaxies might go undetected"
But isn't it that what made the plasma so dense and energetic is
itself the source of the radiation even without recombination? It
gives the sun core as example.. but the sun core still radiate
energy.
What example of plasma object doesn't radiate because it is so dense
and energetic that the protons and electrons can't recombine if it is
at all possible and true?



Yes, if the plasma is too dense and/or too energetic for neutral
atoms
too form, electrons and protons can''t recombine. What you see of the
sun is only the (less dense) atmosphere where the plasma can
recombine
into neutral atoms (see http://www.plasmaphysics.org.uk/research/sun.htm
for a more detailed treatment of this issue).