From: Andy Howell (DAHowell@lbl.gov)
Date: Wed May 15 2002 - 15:35:28 PDT
Lifan Wang wrote:
> I made a fit with the new data and still think 0.56 to be the
>best redshift.
>
>A Ic at 0.33 11 days past max is highly unlikely as Ic at
>that phase are too red to fit the observed.
>
Lifan,
I am not sure what you are talking about. The color is fine. If you
overplot
the dereddened spectrum of 94I at +11d on S02-064 they lie right on top
of each other. See:
http://panisse.lbl.gov/collab/data/spec/homesp/2002/S02-064/S02-064.94I.jpg
or go here for the big picture:
http://panisse.lbl.gov/collab/data/spec/homesp/2002/S02-064/S02-064.html
Here I didn't subtract a host galaxy or monkey with the colors in any way.
If we knew that the host was an elliptical, then we could rule out the
Ic hypothesis, but
Peter and I took a look at the host galaxy and we can't determine the
type from our data.
Also, we did a back of the envelope calcuation, and S02-064 is too
bright in I to be a clone of 94I itself at +11d, but its magnitude is
consistent with another Ic, 83V at +11d which has an almost identical
spectrum at that epoch. Note that I am not saying that S02-064 was
observed at exactly 11d past max -- we don't have great Ic time
coverage, so we can't determine the date very precisely just from the
spectrum.
Actually, I am not convinced that this is a Ic at all. I agree that it
could also be a Ia.
The point of my original email on this subject was that we shouldn't
jump to
conclusions that it is a pre-max Ia at z~0.55. I thought it was
post-max and could go either
way as far as the Ia/Ic identification. I haven't seen anything to
change my mind on this
point. But maybe your new fits will convince me. Please send them and
I will put them on the web page.
-Andy
This archive was generated by hypermail 2.1.4 : Wed May 15 2002 - 15:35:51 PDT
