Electronic Telegram No. 263
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://cfa-www.harvard.edu/iau/cbat.html


SUPERNOVA 2005hd
     The "Nearby Supernova Factory" group (P. Antilogus, S. Gilles, R.
Pain, and R. Pereira, Laboratoire de Physique Nucleaire et de Haute
Energies de Paris; N. Blanc, S. Bongard, Y. Copin, E. Gangler, L.
Sauge, and G. Smadja, Institut de Physique Nucleaire de Lyon; G.
Aldering, S. Bailey, D. Kocevski, B. C. Lee, S. Loken, P. Nugent, S.
Perlmutter, R. Scalzo, R. C. Thomas, L. Wang, and B. A. Weaver, Lawrence
Berkeley National Laboratory, Berkeley; C. Bonnaud and E. Pecontal,
Centre de Recherche Astronomique de Lyon; R. Kessler, Kavli
Institute for Cosmological Physics, Chicago; and C. Baltay, D.
Rabinowitz, and A. Bauer, Yale University) reports the discovery of
a supernova (mag approximately 17.8, calibrated to R) located at R.A. =
4h16m12s.37, Decl. = -13o13'11".6 (equinox 2000.0) in images obtained
on Oct. 21.5 UT using the Quest II camera on the Palomar Oschin
1.2-m telescope as a part of the JPL Near-Earth Asteroid Tracking
component of the Palomar Consortium.  A spectrogram (range 320-1000 nm),
obtained on Oct. 23.5 with the University of Hawaii 2.2-m telescope
(+ Supernova Integral Field Spectrograph), shows the new object to be a
type-II supernova at an approximate redshift of z = 0.03.  The spectrum
consists of a red continuum with obvious broad H-alpha in emission,
along with He I 587.6-nm and Ca II infrared-triplet P-Cyg profiles.
Comparison to a library of supernova spectra reveals a similarity to
the spectrum of the type-IIb supernova 1993J at 18 days after core
collapse (as estimated by Richmond et al. 1994, A.J. 107, 1022).  A
faint host galaxy is discernible on Digitized Sky Survey images below
the (B about 21) limit of the USNO-B1 catalogue.  Adopting z = 0.03 for
the host, a low luminosity of M_B about -14.5 is derived for the host
galaxy.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2005 CBAT
2005 October 24                  (CBET 263)               Daniel W. E. Green