Radiance units are [nW/(cm2 sr cm-1)],
modified to [W/(m2 cm-1)] if the
FLX Flag is enabled.
Radiance units are not
altered by the GHZ
Flag, only the spectral axis units are changed. I realise that this is
not entirely self-consistent, but if you are using the
GHZ flag you probably want to express
radiance as Brightness Temperature
(BBT flag)
or Rayleigh-Jeans Temperature
(RJT flag)
anyway.
However, if you really do want radiance in units of
[nW/(cm2 sr GHz)], multiply by 107/c
(≈1/30), where c is the speed of light in m/s.
The RFM radiance units are set by the First Radiation Constant, C1
in phycon_dat.f90, although the factor 10-5 conversion for
the FLX Flag is applied in
spcout_sub.f90
