Electronic Telegram No. 1581
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
CBAT@CFA.HARVARD.EDU (science)
URL http://www.cfa.harvard.edu/iau/cbat.html


SUPERNOVA 2008hk
     Further to CBET 1559, A. J. Drake, A. Mahabal, S. G. Djorgovski, M. J.
Graham, and R. Williams, California Institute of Technology; M. Catelan,
Pontificia Universidad Catolica; E. C. Beshore, S. M. Larson, and R. Kowalski,
Lunar and Planetary Laboratory, University of Arizona; and E. Christensen,
Gemini Observatory, report the Catalina Real-time Transient Survey discovery
of an apparent supernova in unfiltered Catalina Sky Survey (CSS) images:

 SN       2008 UT       R.A. (2000.0) Decl.      Mag.      Offset
 2008hk   Nov. 6.49    9 12 43.63  + 9 55 47.9   16.7    0".1 E, 0".5 N

The host galaxy, SDSS J091243.63+095548.3, has Gunn magnitudes u = 21.4,
g = 20.3, r = 19.8, i = 19.5, and z = 19.4, photometric redshift z = 0.036,
and a constant magnitude of 19.7 in CSS images taken between 2007 Nov. 4.51
and 2008 Apr. 25.15 UT.  Additional magnitudes for 2008hk obtained with the
Palomar 1.52-m reflector on Nov. 7.39:  16.9 (Gunn g filter), 17.0 (Gunn r),
17.3 (Gunn i).
     R. Chornock, M. Modjaz, and S. B. Cenko, University of California,
Berkeley, report that spectra (range 340-810 nm), obtained on Nov. 23 UT using
the Kast spectrograph on the Lick 3-m telescope, reveal that 2008hk is a
type-Ia supernova at a redshift of 9025 km/s, determined from narrow H-alpha
emission in the spectrum.  Cross-correlation with a library of supernova
spectra using the "SuperNova IDentification" code (SNID; Blondin and Tonry
2007, Ap.J. 666, 1024) finds a best-fit age of 16 +/- 3 days after maximum
light.  The best spectral match found by SNID is with SN 2003du at 18 days
after 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      superseded by text appearing later in the printed IAU Circulars.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 November 25                 (CBET 1581)              Daniel W. E. Green