From: Lifan Wang (lifan@panisse.lbl.gov)
Date: Tue Nov 12 2002 - 23:27:05 PST
I have put flux calibrated spectra of #71 in the directory:
/autofs/lilys/lifan/keckfall
They start with "Cal", and the files contain the sequence numbers
such as 2039 or 2040, the combined file contains 2039_40.
Concerning Andy's remark that the SN match is off in redshift by 0.29,
I do not think this error is significant. In rest frame this difference
amounts only to about 0.15, but there are many uncertainties that
can explain this error, such as the uncertainties in the host galaxy Types,
the spectral template may not be calibrated well, the SN Ia itself
may be a bit different from the best matched template, or simply
it is matched to a wrong date after explosion.
The fits in /autofs/lilys/lifan/keckfall/Calresi2039_40.ec_20A.ps
show that SN 1994D at -03 days @ z = 0.928 gives reasonable fit
as well.
In general, spectral match to such noisy data is not a well posed
question, so it is good to be critical about these figures.
Cheers,
Lifan
> From owner-deepnews@listserv.lbl.gov Tue Nov 12 17:29:19 2002
> X-Authentication-Warning: listserv.lbl.gov: majordom set sender to owner-deepnews@listserv.lbl.gov using -f
> User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.0.1) Gecko/20021003
> X-Accept-Language: en-us, en
> MIME-Version: 1.0
> To: deepnews@lbl.gov
> Subject: Re: Updated summary chart -- with some likely HST choices...
> Content-Type: text/plain; charset=us-ascii; format=flowed
> Content-Transfer-Encoding: 7bit
> Sender: owner-deepnews@lbl.gov
>
> Ok, I have added SuF02-056 from Gemini, added -017 from VLT, fixed my
> broken links,
> and made sure that every SN (except 028, which is worthless) has a
> postscript comparison
> from either me or Lifan.
>
> Can someone *please* send me the data for -071. I don't know what to
> think about it without
> seeing the data. I also still need the data from the last night of
> Keck. None of these things were in
> the data Lifan sent.
>
> Now my thoughts on Saul's suggestions. I pretty much agree with Peter.
>
> 071: I don't like this one because Lifan's fits match at z=0.9, not at
> z=0.928 where the galaxy lines
> are. His fits close to 0.93 are very bad. See #21-24 on:
> http://panisse.lbl.gov/collab/data/spec/homesp/2002/SuF/Calesi2040l_50Asmooth.ps
>
> 060: a very bad candidate from the spectrum. The wiggles match at
> z=0.8 as well as at z=1, and
> neither is particularly convincing. We don't know whether it is a Ia or
> even the redshift
> for certain. If it really is an Elliptical galaxy though, that could
> put this one over the top..
>
> 065: Also not convincing, but I think it is slightly better than 071 or
> 060.
>
> 017: If the Si that Peter is talking about is not a smoothing artifact,
> then this one is a good candidate.
>
> 007: Uncertain redshift, uncertain ID. Hard to justify it.
>
> 012: Again, uncertain redshift, uncertain ID.
>
> 061: haven't seen the data, but it seems like there must be no SN light
> there.
>
> -Andy
>
> Peter Nugent wrote:
>
> >>As you will see on the attached summary chart, our current best bets for
> >>HST include:
> >>071, 060, 065 -- likely options
> >>007, 081, 012 -- still in the game
> >>061 -- still being observed, if possible
> >>
> >>
> >
> >Here are my comments on the above, clearly some of the folks were up on
> >the mountain too long making the reviews.
> >
> >My ordering of the top three high-z candidates are as follows:
> >
> >017 - This one has a good Keck Spectrum of a SN Ia all by itself. Redshift
> >looks to be ~1.0 and one can even see the Si line. It is good to go for
> >all HST observations and the grism wouldn't present any problems.
> >
> >071 - This one has an ok spectrum of a clear SN (but sub-type is a little
> >shaky). The z is from the host at 0.928. It is good for all HST
> >observations and the grism will work as the bright objects miss it with
> >it's specified orientations.
> >
> >065 - Like above, ok spectrum and a z from host of 1.18. It is good for
> >all HST observations but the grism still needs to be checked out for its
> >PA as there may be bright nearby galaxies running all over it.
> >
> >Here is the next tier:
> >
> >060 - This one has shown no signs of SN in the spectrum but it does look
> >like a nice Elliptical galaxy at a z = 1.062. All HST observations work
> >for it and the grism would be ok since the nearby bright objects miss it
> >given it's orientation. Since it is a Elliptical I would be willing to
> >take a chance on it.
> >
> >
> >The last tier, and in my opinion not worthy of following unless we get
> >more data.
> >
> >081 - Redshift uncertain, SN spectrum very questionable (as even in their
> >hope of matching it to z=1.5 still misses a big feature). It also misses
> >the first Nic observation, though it looks like if we push the orientation
> >to the far side of what's allowed it should work. We will ask Ray Lucas
> >about this shortly. Grism observations can not work on this one as it is
> >too faint.
> >
> >007 - No certain redshift and no SN spectrum. Conflicting reports of
> >everything on this one. Works for HST observations but why do it???
> >
> >012 - Once again no certain redshift and no SN signal. It works for the
> >HST observations but would be too faint for the grism.
> >
> >061 - Galaxy only, questionable redshift from one line, no SN. Works for
> >HST observations and the grism.
> >
> >Of course there are a few lower z SNe at z~0.6 that are clear but would
> >not fit the purpose of our high-z campaign.
> >
> >
> >Cheers,
> >
> >Peter (reality) Nugent
> >
> >
>
>
>
--gAD7ET023639.1037171669/venezia.lbl.gov--
This archive was generated by hypermail 2.1.4 : Tue Nov 12 2002 - 23:27:22 PST