Help for PHOTFIT2_BURATTI1


PURPOSE:

In this PDF, the user is asked for the only parameters and there limmits needed 
to fit Buratti's photometric function.
If a sulution guess falls out-of-bonds then the attemp will be aborted and 
a new guess attempted.


MATHEMATICAL BACKGROUND :


bidirectional reflectance [1/str] :

r(i,e,g) = A * cos(i)/(cos(i)+cos(e)) * burf + (1 - A) * cos(i)

burf = ((1 - A) * 2/3 + A*E)*phi - (1 - A) * 2/3 * ((sin(phase) + (PI - phase) * cos(phase))/PI)

BURATTI1 approximation :
phi = 1 + B * phase

REFERENCE :
Bonnie Buratti, Voyager Disk Resolved Photometry of the Saturnian Satellites,
	Icarus, Vol. 59, p. 392-405, 
Bonnie Buratti, Joseph Veverka, Voyager Photometry of Europa,
	Icarus, Vol. 55, p. 93-110, 1983


PROGRAMMER:

Friedel Oschuetz
Institute of Planetary Exploration
DLR
12484 Berlin (FRG)