[IAUC] CBET 1218: 20080121 : SUPERNOVAE 2008H, 2008J, AND 2008K

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                                                  Electronic Telegram No. 1218
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS en CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT en CFA.HARVARD.EDU (science)
URL http://www.cfa.harvard.edu/iau/cbat.html


SUPERNOVAE 2008H, 2008J, AND 2008K
     M. Stritzinger, G. Folatelli, and N. Morrell, on the behalf of the
Millennium Center for Supernova Studies and the Carnegie Supernova Project,
report that they obtained spectra (range 400-1020 nm) of 2008H (cf. CBET
1210), 2008J (cf. CBET 1211), and 2008K (cf. CBET 1211) with the European
Southern Obsrvatory New Technology Telescope (+ EMMI) on Jan. 17.1-17.3 UT.
     The spectrum of 2008J is reminiscent of a type-IIn supernova, displaying
strong emission lines attributed to H_alpha and H_beta.  Each of these
features contains a narrow component superimposed on a broader component.
However, the spectrum is also very similar to the interacting type-Ia/IIn
supernova 2005gj.  The "Supernova Identification" code (SNID; Blondin and
Tonry 2007, Ap.J. 666, 1024) indicates that 2008J is most similar to SN
2005gj at around 14 days past explosion.  The spectrum shows a dip around
628.0 nm that may be due to Si II (rest 635.5 nm); if it is Si II, and
adopting a recession velocity of 4759 km/s for the host galaxy, MCG -02-7-33
(Theureau et al. 1998, A.Ap. Suppl. 130, 333), then it is blue-shifted by
roughly 8200 km/s.  The continuum in the blue region of the 2008J spectrum
is not as strong as seen in the 2005gj spectrum suggested by SNID; this
indicates that 2008J is probably at a more evolved epoch.
     The spectrum of 2008H appears to be that of an older type-II-plateau
supernova.  SNID indicates that 2008H is very similar to supernova 1999em
around a month past explosion.
     SN 2008K is a young type-II supernova.  SNID reveals that 2008K
resembles 2006bp at a week past explosion.  Adopting a host-galaxy recession
velocity of 7997 km/s (Mathewson and Ford, 1996, Ap.J. Suppl. 107, 97) for
the host galaxy, ESO 504-G5, H-beta is measured to be blue-shifted by roughly
10000 km/s.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2008 CBAT
2008 January 21                  (CBET 1218)              Daniel W. E. Green