S02-049

Gemini GMOS Data files:

Date: 16 April 2002

Exposure time:

Data reduced by: Isobel

Weather note:

z (gal): 0.88

z (SN): 0.88 (if cleaned)

SN: [asc] [fits] [2d fits] [ps]

line cleaned SN: [asc] [fits]

Comparison (Cleaned, 5A binned): SN 1981B, max, z=0.88 [ps]

Output file from Andy's program: [txt]

Keck ESI Data files:

Date: 15 April 2002

Exposure time:

Data reduced by: Isobel

Note: This data not nearly as good as Gemini data.

SN: [asc] [fits] [ps]

Isobel (Keck, preliminary): z~0.85?? Maybe a SN bump around 8000A. Needs redoing. Flux in blue though.

Isobel (Gemini, preliminary): I think this one is at z=0.88. It has weak OII, and its neighbour galaxy has strong OII at a very similar z. Its quite clear in the 2d image: S02_049c_2d.fits - look at x=~1240, y=1149. That's the target. The neighbor galaxy is below it. (Scale =0.145"/pix)

Andy (Gemini, preliminary): After running the spectrum through lineclean in IRAF, the best match in the range z=0.4 to 1.2 is at 0.88. My program picks SN 1981B at maximum as the best-fit SN after subtracting an Sa host galaxy.

If I don't clean the spectrum first, then the feature at 9300 A is much deeper, and dominates any fits, producing results that are all over tha place. I don't believe these though. The cleaned version is much better.

Even after cleaning, the match isn't perfect, but that may be because the spectrum is so noisy. So I agree with Isobel that this is probably a Ia at z=0.88. By eye Si 4000/7500 is obvious -- maybe too obvious. If that really is Si 4000, I have never seen it that broad before. Also, the fit in the 7800 to 8000 region is not great.

Tiles

This SN sent to HST ACS.