[IAUC] CBET 2455: 20100914 : SUPERNOVAE 2010hm, 2010ht, AND 2010hu

[quai en eps.harvard.edu]

                                                  Electronic Telegram No. 2455
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director:  Daniel W. E. Green; Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbatiau en eps.harvard.edu (alternate cbat en iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


SUPERNOVAE 2010hm, 2010ht, AND 2010hu
     Further to CBET 2407, A. J. Drake, S. G. Djorgovski, A. Mahabal, M. J.
Graham, and R. Williams, California Institute of Technology; R. H. McNaught
and G. Garradd, Australian National University; J. L. Prieto, Carnegie
Observatories; M. Catelan, Pontificia Universidad Catolica de Chile; E. C.
Beshore and S. M. Larson, Lunar and Planetary Laboratory, University of
Arizona; and E. Christensen, Gemini Observatory, report the CRTS discovery of
two apparent supernovae in unfiltered CCD images taken via the Mount Lemmon
Survey, the Catalina Sky Survey (CSS), and the Siding Spring Survey (SSS).

 SN       2010 UT       R.A. (2000.0) Decl.       Mag.      Offset
 2010ht   Aug. 13.74   23 34 47.45  -12 50 36.1   18.3
 2010hu   Sep. 11.28   23 22 13.33  - 5 19 07.5   18.7    0".5 W, 1" S

Further magnitude estimates of 2010ht from SSS images:  2009 Dec. 19.49
UT, [19.9; 2010 July 20.78, 18.0; 21.83, 18.0; Aug. 20.68, 18.4.
Further magnitude estimates of 2010hu from CSS images:  July 6.39, [20.1
Sept. 11.33, 18.6.

     J. L. Prieto, Carnegie Observatories, and J. Fuentes, Las Campanas
Observatory, report that they obtained optical spectra (range 380-920 nm;
resolution 0.7 nm) of 2010hm (cf. CBET 2442), 2010ht, and 2010hu on Sept.
11-12 UT with WFCCD mounted on the du Pont 2.5-m telescope at Las Campanas
Observatory.  The SNID cross-correlation software (Blondin and Tonry 2007,
Ap.J. 666, 1024) was used to aid identification and age/redshift estimation.
SN 2010hm is a type-II supernova, most similar to the type-IIP supernova
2004dj when close to maximum; after correcting for the recession velocity
of the host galaxy, UGC 12687 (6158 km/s; Theureau et al. 1998, A.Ap. Suppl.
130, 333), a blueshift of the H-alpha P-Cyg profile of 5800 km/s was measured.
SN 2010ht is an old type-II supernova most similar to the type-IIP supernova
2004et at five months after explosion; the redshift obtained from the
supernova features is 0.027 +/- 0.005.  SN 2010hu is a normal type-Ia
supernova about 10 days after maximum light and most similar to SN 1995D; the
SNID redshift obtained from the supernova features is z = 0.088 +/- 0.007.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2010 CBAT
2010 September 14                (CBET 2455)              Daniel W. E. Green