[IAUC] CBET 1817: 20090529 : SUPERNOVAE 2009eq, 2009er, 2009es, 2009et, AND 2009eu

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                                                  Electronic Telegram No. 1817
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVAE 2009eq, 2009er, 2009es, 2009et, AND 2009eu
     P. Challis, Harvard-Smithsonian Center for Astrophysics (CfA), on behalf
of the CfA Supernova Group, reports that a spectrum (range 360-750 nm) of
2009er (cf. CBET 1805), obtained on May 25 UT by S. Tang with the F. L.
Whipple Observatory 1.5-m telescope (+ FAST), shows it to be a type-Ia
supernova.  Cross-correlation with a library of supernova spectra using the
"Supernova Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666,
1024) indicates that 2009eq is subluminous and about one week after maximum
brightness.
     R. J. Foley and P. Challis, CfA, on behalf of the CfA Supernova Group,
reports that a spectrum (range 360-750 nm) of 2009er (cf. CBET 1811), obtained
on May 27 UT by T. Groner with the F. L. Whipple Observatory 1.5-m telescope
(+ FAST), shows it to be a type-Ib supernova.  Assuming a redshift of z about
0.035, the spectrum matches that of SN 2008D (Soderberg et al. 2008, Nature
454, 246; Modjaz et al. 2008, http://lanl.arxiv.org/abs/0805.2201) a few days
past explosion.

     J. M. Silverman, S. B. Cenko, A. V. Filippenko, and W. Li, University of
California, Berkeley, report that inspection of CCD spectra (range 340-1000
nm), obtained on May 28 UT with the 3-m Shane reflector (+ Kast) at Lick
Observatory, shows that 2009eq is probably a type-Ia supernova of the
SN-1991bg subclass (Filippenko et al. 1992, A.J. 104, 1543).  Cross-correlation
with a library of SN spectra using the SNID indicates that it is most like SN
1999by at about three days past maximum brightness.  A spectrum of the galaxy
near SN 2009er (CBET 1811) reveals a recession velocity of 10200 km/s.  The
spectrum of 2009er is very unusual:  there are no conspicuous H Balmer lines
or obvious Si II lines, and it bears some resemblance to the peculiar type-Ib/c
supernova 2006jc (Foley et al. 2007, Ap.J. 657, 105), but with no obvious He I
lines; the exact nature of the supernova is unclear, and follow-up observations
are encouraged.  SN 2009es (CBET 1812) is a type-II supernova.  SNID indicates
that 2009es is about three weeks past maximum and most similar to the normal
type-IIP supernova 2004et at 23 days past maximum; after removal of the
host-galaxy recession velocity of 3900 km/s, determined from narrow emission
lines, the absorption minimum of the H-alpha line is found to be blueshifted by
about 7600 km/s.  SN 2009et (CBET 1813) is also a type-II supernova.  SNID
indicates that 2009et is about one week past maximum and most similar to the
normal type-IIP supernova 2004et at six days past maximum; after removal of the
host-galaxy recession velocity of 8800 km/s, determined from narrow emission
lines, the absorption minimum of the H-alpha line is found to be blueshifted by
about 9000 km/s.  SN 2009eu (CBET 1813) is a normal type-Ia supernova, although
the relative strengths of Ti II and Si II lines suggest that it might be
somewhat subluminous.  SNID indicates that 2009eu is near maximum and most
similar to the type-Ia supernova 2002eu at two days past maximum; after removal
of a recession velocity of 6200 km/s, determined from narrow absorption lines,
the absorption minimum of the Si II 635.5-nm line is found to be blueshifted by
about 9900 km/s.


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                         (C) Copyright 2009 CBAT
2009 May 29                      (CBET 1817)              Daniel W. E. Green