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Date and Time of the Query: 2019-08-24 T02:22:23 PDT
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Notes for object SN 1994D

2 note(s) found in NED.


1. 2007ApJ...671.1084S
Re:SN 1994D
A1. SN 1994D - The photometry used here is from Richmond et al. (1995) and Patat
et al. (1996). In both papers, guidance on photometric uncertainties is
provided, but point-by-point errors are not tabulated. Therefore, the iterated
fitting procedure ({section} 2.5) used elsewhere for perturbing the errors was
used here to set the error scale for each telescope and band. Within a given
telescope's data set, errors also were varied in proportion to flux^-1/2^ and in
concert with the recorded seeing conditions. It was checked that the fitted
light-curve residuals, after normalization to these errors, exhibit no strong
flux dependence.

2. 1999AJ....118.2331V
Re:SN 1994D
A set of short- and long-exposure F555W and F814W images is
available. SN Ia 1994D is clearly seen on the HST images; it occurred
along the edge of the central dusty disk of this host galaxy, just
beyond or north of the prominent dust lanes (Fig. 23). Although the SN
is saturated in the long-exposure images, only the central pixels of the
SN profile are saturated in the shorter exposures.
We have measured the magnitudes of the SN in the two HST filters by
using the wings of the stellar profile and interpolating the flux lost
in the saturated portion of the profile. We used the unsaturated
magnitudes of the field star (which is "star C" in Richmond et al.
1995), also seen on the image, as a reference. We find
m_F555W_ = 14.48 +/- 0.08 and m_F814W_ = 14.19 +/- 0.08 mag for SN 1994D
on 1994 May 9 UT. These values agree well with V = 14.40 and I = 14.19
mag for 1994 May 8 UT by Richmond et al. (Our measurements for the field
star magnitudes, m_F555W_ = 16.35 and m_F814W_ = 15.51 mag, also agree
well with Richmond et al.'s magnitudes for this star.)
The SN environment is dominated by diffuse starlight in the host
galaxy. We averaged the measurements of the magnitude and color of the
SN environment on the deeper images through two 0.5" -radius apertures,
placed on either side of (and outside) the wings of the saturated SN
PSF. We find that m_F555W_ = 19.40 and F555W - F814W = 1.52 mag in the
environment, which is quite red. Undoubtedly, dust must be contributing
to the colors of this environment, but taken at face value, the color
implies the presence of K-type stars, presumably giants, in the SN
environment in this early-type host galaxy.


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