[IAUC] CBET 1250: 20080210 : SUPERNOVA 2008ae IN IC 577

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                                                  Electronic Telegram No. 1250
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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SUPERNOVA 2008ae IN IC 577
     S. Blondin, Harvard-Smithsonian Center for Astrophysics (CfA), on behalf
of the CfA Supernova Group, reports that a spectrogram (range 350-740 nm) of
2008ae (cf. CBET 1247), obtained by M. Calkins on Feb. 10.35 UT with the F. L.
Whipple Observatory 1.5-m telescope (+ FAST), shows it to be a peculiar
type-Ia supernova around one week before maximum light.  Cross-correlation
with a library of supernova spectra using the "Supernova Identification" code
(SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) indicates that 2008ae is most
similar to the peculiar 2002cx-like type-Ia supernova 2005hk (Phillips et al.
2007, PASP 119, 360) at 4 days before maximum.  The spectrum consists of a
blue continuum with P-Cyg profiles of high-ionization lines characteristic of
the overluminous type-Ia supernova 1991T (cf. IAUC 5239, 5251); yet the
discovery magnitude of 17.8 corresponds to an absolute magnitude of -17.7
(assuming the galaxy is in the Hubble flow and the supernova suffers
negligible extinction), similar to underluminous, 1991bg-like supernovae at a
similar age.  This was also the case for the peculiar supernova 2005hk (cf.
IAUC 8625, CBET 268), which confirms the resemblance between the two events.
Adopting a recession velocity of 9022 km/s for the host galaxy (from The
Updated Zwicky Catalog, http://tdc-www.harvard.edu/uzc/), the maximum
absorption in the weak Si II line (rest 635.5 nm) is blueshifted by roughly
7900 km/s, while the maximum absorptions in the Fe III lines (rest 440.4 and
512.9 nm) are blueshifted by roughly 8700 and 6700 km/s, respectively.  These
relatively small blueshifts are characteristic of 2002cx-like supernova events.


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                         (C) Copyright 2008 CBAT
2008 February 10                 (CBET 1250)              Daniel W. E. Green