From: Robert A. Knop Jr. (robert.a.knop@vanderbilt.edu)
Date: Fri Apr 11 2003 - 09:09:22 PDT
On Fri, Apr 11, 2003 at 05:06:14PM +0200, Ariel Goobar wrote:
> and it looks very good, except for epochs earleir than -7.
That latter bit doesn't surprise me, nor does it worry me much. I just
put in the standard 20-day rise time parabola as with the other
lightcurves, and joined it to a spline; there wasn't really anything
early on to constrain it (using the five literature SNe that I had), so
I had to pick a rise time.
> Serena has started to look at the U-B intrinsic color dispersion
> in the Jha data, but the host galaxy reddening corrections are still not
> worked out. Without correcting for that (nor stretch) she is finding a
> scatter at maximum of 0.18 mag.
Is this intrinsic, i.e. have the measurement uncertainties been
subtracted out? Peter gave me numbers yesterday, 0.1 and 0.04, as
residuals from a stretch/magnitude fit; those are *intrinsic*, in that
you add the measurement errors to get the total dispersion. The latter,
smaller dispersion is when the two dimmest outlyers (i.e. those we were
unlikely to find) are omitted.
-Rob
-- --Prof. Robert Knop Department of Physics & Astronomy, Vanderbilt University robert.a.knop@vanderbilt.edu
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