From: Andy Howell (DAHowell@lbl.gov)
Date: Wed Mar 19 2003 - 19:22:24 PST
Colleagues,
(It is easiest to read this mail in a fixed width font in a big window.)
Here is my proposed revision of the circular for the Fall 2002
Subaru run in the format we discussed at the teleconference.
We need to settle some outstanding issues that I have
highlighted below. Once I hear back from the appropriate
people I will make the next draft and send it to Mamoru to make the
final version.
If you want to refer to the data that I was looking at to generate
the comments I made for each SN, SNMinuit fits are here:
http://panisse.lbl.gov/collab/observing/schedule2002/2002B/lightcurves/
The spectra pages are here: http://panisse.lbl.gov/collab/data/spec/
------------------
M. Doi, Univ. of Tokyo, on behalf of the Supernova Cosmology
Project (cf. IAUC 7763 and 7764, plus V. Prasad, G. Sainton, E.
Smith, and A. Spadafora) and the Subaru high-redshift supernova
search group (N. Yasuda, N. Kashikawa, K. Motohara, T. Morokuma,
K.Sekiguchi, G. Kosugi, H. Furusawa, Y. Komiyama, T. Takata,
M. Ouchi, Y. Ohyama, and Subaru Observatory SXDS Project members),
reports the discovery of XX supernovae found with Subaru
telescope +prime-focus Suprime-Cam in SDSS i' band. Reference
images were taken on Sep. 30 and Oct.1, 2002. The limiting magnitude
of reference images was about 26.6mag (S/N=5 for 2arcsec aperture).
We took search images on Nov. 3.
Follow-up photometry was carried out with Suprime-Cam, and we
confirmed SN signals at least 3 epochs among 7
(Nov.3,6,10,28,30,Dec.7,8) for 30 SNe below.
The supernova spectra were obtained with GMOS on Gemini-N on
Nov. 6, 8, and 9; with ESI on KeckII on Nov. 6, 7, 9,
and 10; with FORS2 on Yepun (VLT-UT4) on Nov. 7 - 11; and
with FOCAS on Subaru on Nov. 12. Redshifts were obtained for XX
SNe using either the host galaxy spectrum (denoted with *)
or with template spectrum fitting of a SN.
SCPname R.A. (J2000) Decl. i' z type offset Comments
SuF02-060 02:17:34.51 -04:53:46.6 24.5 1.063* Ia 0.0" LC
ok. 7 points. s=0.80. Spectrum plausible, not convincing. Peter says
E galaxy -> Ia. Grism spectra exist.
SuF02-017 02:16:45.71 -05:09:51.2 25.0 1.03 Ia no host
Feature could be Si 4000 if smoothed, but maybe too broad. LC poor, but
declining. s=0.65.
SuF02-025 02:16:23.93 -04:49:29.4 24.5 0.606* Ia 0.2" W Si.
Confirmed Ia. Excellent LC. s=0.83, including rise.
SuF02-001 02:17:00.05 -04:58:19.6 23.4 0.57 Ia 0.5" W aka
SuF02-027. Certainly Ia. LC 7 points. Several sigma off, but reasonable
s=0.83
SuF02-065 02:17:34.53 -05:00:15.4 25.2 1.181* SN 1.3" SSE Peter
says LC is like Type II. SN minuit says Ia could fit s=1.07. Big
errors, residuals.
SuF02-007 02:18:52.36 -05:01:13.2 24.8 1.18: SN no host Chris
says z=1.54, but that would make it too bright. z uncertain -> type
uncertain. LC ok, s=0.99 @ z=1.18
SuF02-071 02:17:08.63 -05:02:06.4 23.8 0.928* SN 1.4" E At
that redshift, Ia features do not seem to match. LC good fit, 7pts,
falling, s=0.86.
SuF02-037 02:17:43.30 -04:30:56.7 24.6 0.926* SN 0.4" E One
bump in the spectrum. Ok LC, rises, falls. 4 points, s=0.77
SuF02-000 02:17:42.54 -05:06:34.0 24.8 0.92* SN 0.5" NE Almost
all galaxy light in spectrum, but LC good -- rises, falls. s=0.73
SuF02-002 02:17:12.24 -04:55:08.7 24.4 0.823* SN 0.3" NW Chris
(prelim) says: Wiggles don't seem to match a Ia at this redshift. Now
says: Possible SN. Good LC fit, s=0.75
SuF02-055 02:18:53.20 -04:32:59.2 23.7 0.66 SN 0.6" N One
bump in the spectrum. Well fit LC, but only 4 points. s=1.08
SuF02-082 02:18:40.73 -05:03:44.3 25.3 0.623* SN 1.1" NNW
Essentially a featureless spectrum. LC not great, but rises, falls, 7
points, s=1.01 +/- 0.07
SuF02-077 02:18:35.15 -04:26:38.9 25.1 0.59 SN 0.6" NW I
don't have the spectrum. LC 4 points, rising, falling, s=0.73
SuF02-019 02:17:38.08 -05:08:46.8 24.5 0.505* SN 0.3" NW
Featureless, mainly galaxy light. LC poor, but declining.
SuF02-012 02:18:51.59 -04:47:24.8 25.1 1.3: SN 0.2" N Many
minima in z space. Grism spectra exist. LC poor, but declining @ z=1.3
SuF02-081 02:20:07.55 -05:08:27.2 25.1 1.478* ? 0.0"
Spectrum misses big feature for Ia if z is correct. LC terrible at
z=1.48, 3 points
SuF02-061 02:17:22.73 -05:16:56.1 24.7 1.08: ? 0.0" I
don't have the spectrum. No LC.
SuF02-005 02:18:35.70 -04:31:11.0 24.6 0.863* ? 0.3" NE No
LC. No good SN fit. Chris: Weird. Very broad bump at 8500 Angstroms.
SuF02-021 02:18:10.56 -04:40:20.6 24.6 0.69 ? 2.9" SSW Two LC
points. Drops like a rock. I don't have the spectrum, but Saul's notes
don't mention a match to a Ia.
SuF02-028 02:16:56.37 -05:00:57.4 24.9 0.347:* ? 1.5" SE No
LC. Chris: No evidence for a SN. Another weird one. The spectrum falls
off after H-alpha.
SuF02-059 02:20:28.06 -04:58:50.3 25.7 0.269* ? 0.2" E
Spectrum pretty flat. How can it be at I=25.7 and z=0.269? LC
terrible, 3 points, s=0.55, and huge errors. Is z wrong?
SuF02-083 02:18:06.22 -05:00:38.1 26.0 1.272* ? 0.4" S Flat
spectrum.
SCPname R.A. (J2000) Decl. i' host info.
SuF02-034 02:18:31.21 -05:01:24.4 25.6 0.2" N
SuF02-004 02:18:09.01 -04:54:17.9 25.1 0.6" SE
SuF02-086 02:17:16.18 -05:06:02.7 26.2 no host
SuF02-076 02:16:26.37 -05:04:32.5 26.1 no host
SuF02-J01 02:17:45.97 -04:36:46.2 25.2 0.2" W
SuF02-051 02:17:27.48 -04:40:45.2 25.4 no host
SuF02-057 02:20:13.92 -05:07:36.0 25.6 no host
SuF02-056 02:20:00.03 -04:44:20.2 24.3 0.5" SE
Outstanding questions:
- If SuF-065 drops like a Type II according to Peter, why does it look
reasonable as a SNMinuit fit?
I he is right about that, then does that not call into question all
SNMinuit fits?
- SuF02-061, 21 are now "?", but could be resurrected as SN depending on
the spectra,
which I don't have because they are from the last night of Keck. I also
don't have SuF02-077.
I don't know their reduction status. Lifan, can you get the data from
Greg and look at it?
- Peter says SuF-060 is in E galaxy, thus the classification as Ia. I
didn't note where that came from.
Are you confident of that, and do we want to classify something as a Ia
at z=1 based on this?
Maybe we should note the reason for the classification.
- SuF02-081 I have listed as '?' now, because I'm not sure if we can
rule out some kind of AGN.
It has 0 offset from core. I am open to suggestions. Greg, you
mentioned the possibility of
a BLLac. You know more about that than me. Is this possible?
- We may have to lose 005, 028, 059, 083, and possibly (61 and 21
pending looks at the Keck spectra)
unless someone finds evidence that they are SNe. I propose dropping
them, and I will do that
in the next draft unless someone has a reason to keep any of them.
- Can someone give me LC points for the second set of SNe without
spectra? What should we
say about these?
- I took off the date category, since they were all the same. If that
information was correct,
someone should add it to the text. I didn't really follow that part of
the discussion today
at the teleconference, so someone on the Subaru side will have to
address this.
- The original draft said: "The magnitude increase of the SNe compared
with the images in the
reference are given in the table below (photometric accuracy 0.1-0.2mag)."
I don't think we need to say this explicitly because people will
understand that we are
reporting discovery magnitudes.
-Andy
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