From: Vitaliy Fadeyev (VAFadeyev@lbl.gov)
Date: Fri Jan 23 2004 - 19:31:05 PST
Hi Serena,
these are the results of my fits to SN 1999Q lightcurves:
case m_B dm_R m_B_corr dm_B_corr s ds chisq dof m_R kcorr_R kcorr_I tmax dtmax R-I d(R-I)
1 22.82 0.06 23.02 0.16 1.117 0.054 5.29 8 22.06 -0.764 -0.310 2451186.54 1.444 -0.054 0.074
2 23.43 0.03 23.59 0.08 1.086 0.031 19.85 9 22.39 -1.042 -0.531 2451197.52 0.000 -0.323 0.029
3 23.14 0.02 23.34 0.07 1.119 0.032 9.95 9 22.24 -0.902 -0.419 2451191.83 0.853 -0.188 0.035
The fit "cases" are as follows:
1) stand-alone HST data, no constraints. In this case, the day
of max is shifted to earlier time by 11 days compared to what
Riess has reported. The Chi^2 is good (too good).
2) the maximum is fixed to the Riess's value. The Chi^2 becomes
"bad".
3) Greg pointed out that IAU circular contains the I band discovery
magnitude. I assumed that that data value has error of 10%
and that it was measured with similar filter to F814W. Adding
this point resulted in third case. The day of max is about 6 days
earlier than reported value, Chi^2 is good.
So, you can take this with appropriately sized grain of salt or
other substances. Feel free to critisize.
If B band stretch value is all you care about, then it seems that
proper value would be about 1.1 . However, the time-of-max discrepancy
is worriesome.
Cheers,
vitaliy
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