Capital Sigma seems to be used in radio astronomy. eg A&A 376, 641 (2001):
"radio surface brightness of Sigma < 2 x 10**22 Watt / m**2 / Hz / sr"
Radio tends to use Jy/beam
On Tue, 14 Dec 2004, Malcolm J. Currie wrote:
> mu is certainly what's used in the optical. It's less confusing than it
> might be; we don't have micromags per sq. arcsec. I can't say what is
> used for other wavelength regimes.
>
> Malcolm
>
--
Tim Jenness
JAC software
http://www.jach.hawaii.edu/~timj
|