From: Serena Nobili (serena@lpnhep.in2p3.fr)
Date: Wed Oct 27 2004 - 07:12:04 PDT
Dear Saul and Greg,
I have not answer to this comment yet, and I apologize for the delay. As
Greg noticed, 6/42 SNe are not well fitted on the rise, while 7/42 are
well fitted on the rise. I have been looking for behavior of the 6 SNe,
which are not well fitted, especially in the residuals of the Hubble
diagram, that can indicate a systematic effect.
Unfortunately, only 3 out of the 6 are in the Hubble flow. These are:
# sn z Imax err_Imax residuals
1992bo 0.0170 15.710 0.138 0.332
1995bd 0.0140 14.939 0.162 -0.012
1999aa 0.0150 15.250 0.146 0.148
As you see from the last column the residuals do not indicate any
systematic trend. Thus, I deduce the fitting procedure, although not
optimal for describing the rise time, does not introduce systematics we
should worry about. This is confirmed in the rest of the analysis
presented in the paper, i.e. there is no different behavior of these 6
SNe compared to the rest of the sample.
I hope this answers Greg's comment.
I am adding a comment about this in the paper.
Cheers,
Serena
On Tue, 26 Oct 2004, Saul Perlmutter wrote:
> Hi Serena, I was looking in the email archive to see if you had
> answered Greg on this one of his questions:
>
>
> b) The systematic deviations from the fits need to be addressed head-on.
> 6 of 42 SN have deviant rising fits while 7 or 42 have reasonable
> rising fits (the rest lack data). So, the fitting method works only
> half the time when there is rising data. Of those with a
> well-constrained 2nd peak, 2 fit poorly while 16 are well-fit.
> In particular, the poor chi^2 for 94D is due to a systematic failure
> of the model, not to poor NIR photometry or underestimated error bars
> (as the paper now suggests). As no high-z SNe have rising data, you
> may simply have to cut out the rising part - at least as a test of
> whether these systematic errors matter.
>
> I found the email saying that you *were* going to answer, but not the
> answer. Did it not end up in the archive? Thanks, --Saul
>
>
>
>
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