From: Robert A. Knop Jr. (robert.a.knop@vanderbilt.edu)
Date: Fri Apr 11 2003 - 11:09:05 PDT
See attached PS file. Using an intrinsic dispersion of 0.095 in U-B
doesn't puff things out too horribly, and (unsurprisingly) it's all
along the major axis.
Using 0.045 is about halfway between the "none" and the "0.095"
contours.
The question is: which value to use? 0.095 is more conservative,
obviously. 0.045 has the advantage of giving us smaller error bars.
Especially given that I'm not doing U-B as a function of stretch, it's
probably more fair to use the bigger dispersion. It has the added
advantage of being very close to what I would have used given the five
UV supernovae I quote in the paper.
The chisquares acutally don't improve all that too terribly much: from
75.7 to 73.0 going from no U-B intrinsic color dispersion to 0.095
magnitudes of intrinsic U-B. (Both with 64 supernovae.)
-Rob
-- --Prof. Robert Knop Department of Physics & Astronomy, Vanderbilt University robert.a.knop@vanderbilt.edu
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