[IAUC] CBET 3758: 20131218 : SUPERNOVA 2013hk

[quai en eps.harvard.edu]

                                                  Electronic Telegram No. 3758
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


SUPERNOVA 2013hk
     B. J. Shappee, C. S. Kochanek, K. Z. Stanek, T. W.-S. Holoien, J.
Jencson, and J. F. Beacom, Ohio State University; J. L. Prieto, Princeton
University; D. Szczygiel and G. Pojmanski, Warsaw University Observatory;
J. Brimacombe, Cairns, Australia; and D. Bersier, Liverpool John Moores
University, report the discovery of an apparent supernova (mag 15.9) on V-band
images obtained during the on-going "All Sky Automated Survey for SuperNovae"
(ASAS-SN), using data from the recently expanded quadruple 14-cm "Brutus"
telescope at Haleakala, Hawaii.

 SN       2013 UT       R.A. (2000.0) Decl.      Mag.
 2013hk   Dec. 4.86    3 02 10.85  +15 55 38.8   15.9

Nothing was visible at this position on Nov. 19.96 UT (V > 17).  The variable
is located near the center of PGC 2816341.  The discovery image is posted at
URL http://www.astronomy.ohio-state.edu/~assassin/followup/ASASSN-13dm.png.
The new object was also detected in images taken on Dec. 5.85, 6.83, 7.84, and
9.83.

     A. Pastorello, M. Turatto, L, Tomasella, P. Ochner, S. Benetti, E.
Cappellaro, and N. Elias-Rosa, Osservatorio Astronomico di Padova, Istituto
Nazionale di Astrofisica, report that an optical spectrogram (range 340-820
nm; resolution 1.3 nm) of 2013hk, obtained on Dec. 12.95 UT with the Asiago
1.82-m Copernico Telescope (+ AFOSC), shows it to be a type-Ia supernova.
Adopting a redshift z = 0.017 for the host galaxy (PGC 2816341; Miller and
Owen 2001, Ap.J. Suppl. 134, 355), a good match is found with the type-Ia
supernova 2000E (Valentini et al. 2003, Ap.J. 595, 779) at 8-10 days past
B-band maximum light.  A prominent, narrow interstellar Na I feature is
visible at the redshift of the host galaxy, with an equivalent width of 0.25
nm, suggesting significant internal reddening.  Adopting the relation of
Turatto et al. (2003, in *From Twilight to Highlight: The Physics of
Supernovae*, ed. by Hillebrandt and Leibundgut, Berlin: Springer, p. 200),
E(B-V) = 0.4 is inferred due to the host galaxy.  The expansion velocity of
the ejecta, as deduced from the position of the minimum of the Si II
635.5-nm line, is 10200 km/s.  The Asiago classification spectra are posted
at website URL http://sngroup.oapd.inaf.it.  The classification is made via
GELATO (Harutyunyan et al. 2008, A.Ap. 488, 383) and SNID (Blondin and Tonry
2007, Ap.J. 666, 1024).


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2013 CBAT
2013 December 18                 (CBET 3758)              Daniel W. E. Green