[IAUC] CBET 1271: 20080228 : SUPERNOVAE 2008an AND 2008aq

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                                                  Electronic Telegram No. 1271
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 2008an AND 2008aq
     Further to CBET 1255, J. Chu, W. Li, and A. V. Filippenko, University
of California at Berkeley, report the LOSS discovery of an apparent supernova
on unfiltered KAIT images:

SN       2008 UT        R.A. (2000.0) Decl.     Mag.     Offset
2008aq   Feb. 27.44   12 50 30.42 -10 52 01.4   16.3   15".2 E, 45".2 S

Additional KAIT magnitudes for 2008aq in MCG -02-33-20:  Feb. 10.47 UT,
[19.1; 28.40, 16.2.
      S. Blondin, Harvard-Smithsonian Center for Astrophysics (CfA), on
behalf of the CfA Supernova Group, reports that a spectrogram (range 350-740
nm) of 2008aq, obtained on Feb. 28.45 UT by G. Narayan with the F. L. Whipple
Observatory 1.5-m telescope (+ FAST), shows it to be a young type-II/IIb
supernova.  The spectrum displays broad P-Cyg profiles from the Balmer
series, typical of young type-II supernovae, and, in addition, an absorption
feature that may result from a blend of He I 587.6-nm and Na I D and that is
particularly strong in type-Ib supernovae.  SN 2008aq may thus evolve into a
"type-IIb"-like event.  Cross-correlation with a library of supernova spectra
using the "Supernova Identification" code (SNID; Blondin and Tonry 2007,
Ap.J. 666, 1024) indicates that 2008aq is similar to the type-IIb supernova
2006T (CBETs 386, 425) at around one week before maximum light.  Adopting a
recession velocity of 2397 km/s for the host galaxy (de Vaucouleurs et al.
1991, Third Ref. Cat. of Bright Galaxies, ver. 3.9), the maximum absorption
in the H_alpha line (rest 656.3 nm) is blueshifted by roughly 14000 km/s.
     Blondin et al. add that a spectrogram of 2008an (cf. CBET 1268),
obtained as above on Feb. 28.53 UT by Narayan, shows it to be a type-Ic
supernova around maximum light.  Cross-correlation with a library of
supernova spectra using SNID code indicates that 2008an is most similar to
the type-Ic supernova 1994I at two days past maximum light.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2008 CBAT
2008 February 28                 (CBET 1271)              Daniel W. E. Green