Subject: another paragraph
From: Barbara Emery <[email-masked]>
To: [email-masked]
Cc: [email-masked]
Date: Wed, 3 Jun 2009 19:36:12 -0600 (MDT)

3 June 2009

Dear Astrid,

This paragraph goes in 'Electron precipitation', between the first paragraph,
and the second paragraph which should start with 'The TIEGCM defines..'.
Please add this and the new text I put in by hand with Wenbin's comments
in red before giving a clean copy to Alan to look at.  I put the corrections
on your chair.

Thanks!

- Barbara

P.S. I am gone until Monday June 8.

The auroral radius (Ra) is set by the larger of:
Ra(CPCP) = -0.43 + 9.69 * (CPCP**0.1875)        (2.11)
or
Ra(HP) = 14.20 + 0.96*Pl                        (2.12)
where P1 = 2.09*ln(HP) is the hemisphere power level, so Ra=max(Ra(CPCP),Ra(HP)).
Recall from Equation 2.4, that the Heelis radius of convection (theta0)
is similar to Ra(CPCP) above, where CPCP**0.1875 is also used.
[CONSIDER adding a plot of theta0 and Ra(CPCP) and Ra(HP) for
Kp formalizations of HP and CPCP.]
For the Weimer 2005 convection model, the Weimer CPCP averaged from both
hemispheres is used to find the parameterized theta0(param) from Eq. 2.4,
even though the real theta0=bndyfitr/2.  Ra(param) is the larger of
Ra(CPCP) from Eq. 2.11 or Ra(HP) from Eq. 2.12.  The difference between
the larger auroral radius and convection radius, or diffrac in wei05loc,
is approximately 2.5 degrees, but varies.
[CONSIDER another plot based on plot above of the difference between
Ra(param) and theta0(param).]
This parameterized difference in the radii is then used to find the
auroral radius used with the Weimer 2005 ion convection radius where
Ra(with Weimer 2005) = theta0(=bndfitr/2.) + diffrac    (2.13)