Electronic Telegram No. 2221
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director:  Daniel W. E. Green; Room 209; Dept. of Earth and Planetary
 Sciences; Harvard University; 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbat@iau.org; cbatiau@eps.harvard.edu
URL http://www.cfa.harvard.edu/iau/cbat.html


SUPERNOVA 2010as IN NGC 6000
     M. Stritzinger, J. L. Prieto, and N. Morrell, Carnegie Observatories;
G. Folatelli, Universidad de Chile; and G. Pignata, Universidad Andres Bello,
on behalf of the Carnegie Supernova Project and the Millennium Center for
Supernova Science, communicate that they obtained optical spectra of 2010as
(cf. CBET 2215) on Mar. 20.1 and 22.1 UT with the Du Pont telescope (+ WFCCD),
and on Mar. 21.1 with the Gemini-South telescope (+ GMOS).  The spectra
suggest that this object is a young type-Ib/c supernova, resembling supernova
2007Y (Stritzinger et al. 2009, Ap.J. 696, 713) at two weeks before maximum.
The spectra exhibit a number of strong and shallow features.  Prevalent P-Cyg
absorption lines are present at 620 and 820 nm, which are attributed to
H-alpha and the Ca II triplet, respectively.  Adopting a host-galaxy
recession velocity of 2193 km/s (Theureau et al. 1998, A.Ap. Suppl. 130, 333)
for the host galaxy (NGC 6000), H_alpha and the Ca II triplet are measured to
be blue-shifted in the first spectrum by roughly 16700 and 15600 km/s,
respectively.  Strong multi-component Na I D interstellar absorption lines
are present in the spectra, indicative that this supernova suffers
considerable reddening.


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      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2010 CBAT
2010 March 23                    (CBET 2221)              Daniel W. E. Green