SN 1991bg Ia in NGC 4374 (M84) in the Virgo Cluster
OBJECT: SN 1991bg Ia in NGC 4374 (M84) (E1 galaxy {leibundgut1993}) in the Virgo cluster which in
Leda is
Leda: NGC 4374.
DISCOVERY: 1991dec3.78 by Kosai et al. (1991)
MAXIMUM: 1991dec13.0 (JD 2448603.5) in B which we estimate by subtracting 2.0 days from
the Vmax date of filippenko1992 and turatto1996: 1991dec13.0 +/- 1.0. is what
filippenko1992 adopts on p. 1547.
leibundgut1993 found Vmax on 1991dec14.7 +/- 0.5. (and gave JD 2448605.3), but if 14.7 is right,
then they meant JD 2448605.2.
SN 1999by which was similar to 91bg had Bmax 2.0 days before Vmax
garnavich2004.
See the US Navy Observatory
Julian Date Converter.
This day of the year 348.
SUPERNOVA of the YEAR: M = 59.
HEADER: Header Common header information for this supernovae.
The common header may (or may not) be updated relative to the header information here
(D. J. Jeffery (2007jan01)).
COMMENTS: This is the prototype cool SN Ia.
Spectrum Date Phase relative to Bmax Wavelength Range
leibundgut1993 1991dec13.49 0.5 4658.4808772--7064.6622
filippenko1992 1991dec13 0.6 3300.000--8680.000
leibundgut1993 1991dec31.56 18.56 3187.75--7889.925982 (observer)
turatto1996 1992jan02 20.35 4099.9981956649--7811.29438878776 (rest???)
leibundgut1993 1992jan07.34
filippenko1992 1992mar13 91.47 3701.2869--9794.8690 (observer)
REFERENCES:
branch2006b The SN Ia at-maximum-light
paper with the subtypes defined.
CfA List of Supernovae
where SN 1991bg is noted.
CfA Supernova Archive
This has 9 SN 1991bg spectra which probably are some of the ones I have, but in different versions.
conley2006 General value
of 19.4 days for Ia rise time in B.
But 91bg may well have had a shorter rise.
\citet{filippenko1992d}
Specifically on SN 1991bg.
\citet{leibundgut1993}
Specifically on SN 1991bg.
paturel2003 (Leda) Leda refererence.
SUSPECT Index.
SUSPECT Index: SN 1991bg Ia.
There are 26 SN 1991bg spectra.
turatto1996
Specifically on SN 1991bg.
CORRECTIONS: Heliocentric velocity 946 +/- 48 km/s (2007jul06) from
Leda: NGC 4374
Galactic foreground reddening 0.18/4=.045 reddening from
Leda: NGC 4374
This is derived from
Schlegel et al. (1998)
OBSERVATIONS: From
1) David Jeffery's old catalog: these came from leibundgut1993 and filippenko1992d.
The leibundgut1993 ones are probably those in the CfA supernova archive.
2) SUSPECT: These are the turatto1996 and gomze1996 spectra.
3) David Branch: he has all the filippenko group spectra in fnu format with duplication
in /home/branch/synow/91bg. No information on redshift correction.
He's also has some of mine somewhere too maybe.
4) Eddie Baron: none.
SPECTRUM LOG:
JD times for the SN 1991bg spectra of all kinds of people.
Bmax estimate 1991dec13.0 (JD 2448603.5).
JD Bmax Heliocentric velocity (Leda, 2007jul06)
8603.5 946.
Heliocentric velocity Z redshift
946.0000000000 0.0031555163
Index JD of some kind Observer phase Rest phase
1 8603.9900000000 0.4900000000 0.4884586607 ! leibundgut1993 1991dec13.49
2 8604.0800000000 0.5800000000 0.5781755576 ! filippenko1992 1991dec13.58 3300.000--8680.000 (rest)
3 8622.0600000000 18.5600000000 18.5016178426 ! leibundgut1993 1991dec31.56 3187.75 --7889.925982 (observer)
4 8623.0100000000 19.5100000000 19.4486295317 ! filippenko1992 1992jan01.51 3240.000--9910.000 (rest)
5 8623.8500000000 20.3500000000 20.2859872358 ! turatto1996 1992jan02.35 4099.9981956649--7811.29438878776 (observer)
6 0.0000000000****************************** ! The wavelength calibration is
7 0.0000000000****************************** ! in error somehow.
8 8694.9700000000 91.4700000000 91.1822728481 ! filippenko1992 1992mar13.47 3701.2869--9794.8690 (observer)
&specnamelist
aname='sn1991bg Ia 1991_12_'
ebv=.045 !
epoch= ! This parameter needs to updated for the particular spectrum.
idifmake=0
iformat=1
ismooth=0
itick=2
itickln=4
t_rise=19.4d0 ! \citep{conley2006}, Just an average rise time.
v_helio=946.
ymin2=1.d-16
ymax2=10.d-15
ymin3=.3
ymax3=3.
wlammin1=
wlammax1=
wlammin2=
wlammax2=
wlammin3=
wlammax3=
/
Postscript plot of the spectrum.
Postscript plot of the spectrum with local normalization.
Information from somewhere and someone.
