[IAUC] CBET 3444: 20130324 : SUPERNOVA 2013aq IN NGC 5604 = PSN J14244257-0312309

Sab Mar 23 21:23:10 ART 2013

                                                  Electronic Telegram No. 3444
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 2013aq IN NGC 5604 = PSN J14244257-0312309
     Stuart Parker, Oxford, Canterbury, New Zealand, reports the discovery of
an apparent supernova (mag 16.7) by Peter Aldous (Geraldine, Canterbury, New
Zealand) and an independent discovery by Parker himself.  Aldous' 60-s
unfiltered image (limiting mag 18.0) was taken on Mar. 13.492 UT with a
Celestron 35.6-cm Schmidt-Cassegrain reflector (+ SBIG ST8 camera).  Parker's
30-s unfiltered image (limiting mag > 19) was taken on Mar. 13.642 with a
30-cm Astro-Tech AT12RC Ritchey-Chretien astrograph (+ ST10 camera) at his
Parkdale Observatory in the course of the Backyard Observatory Supernova
Search.  The new object is located at R.A. = 14h24m42s.57, Decl. = -3d12'31".0
(equinox 2000.0; reference stars from USNO-B and UCAC3 catalogues), which is
5" west and 13" north of the nucleus of the galaxy NGC 5604.  Nothing is
visible at this position on Digitized Sky Survey red and infrared images
(limiting red magnitude > 19).  The variable was designated PSN
J14244257-0312309 when it was posted at the Central Bureau's TOCP webpage
and is here designated SN 2013aq based on the spectroscopic confirmation
reported below.  Joseph Brimacombe, Cairns, Australia, reports mag 17.0 and
position end figures 42s.44, 29".7 for 2013aq from images obtained on Mar.
14.791 with a 41-cm RCOS telescope (+ infrared filter; bandpass > 700 nm);
his image is posted at http://www.flickr.com/photos/43846774@N02/8559042332/.

     M. Childress, R. Scalzo, F. Yuan, B. Tucker, and B. Schmidt, Australian
National University (ANU), report spectroscopic classification of PSN
J14244257-0312309 = SN 2013aq as an old type-II supernova.  They obtained a
20-min spectrogram of 2013aq on Mar. 14.72 UT with the Wide Field
Spectrograph (WiFeS; Dopita et al. 2007, Ap. Space Sci. 310, 255) on the
ANU 2.3-m telescope at Siding Spring Observatory, using the B3000/R3000
gratings (range 350-980 nm; 0.1-nm resolution).  The spectrum of 2013aq was
compared to supernova spectral templates using SNID (Blondin and Tonry 2007,
Ap.J. 666, 1024), and the top matches were consistently type-IIP supernovae
at ages of 2-3 months with mean redshift of z = 0.008 +/- 0.003, consistent
with the redshift of the apparent host galaxy, NGC 5604, of 0.009166
(Theureau et al. 1998, A.Ap. Suppl. 130, 333; via NED).  SN 2013aq has a
cool spectrum characterized by broad P-Cyg H_alpha emission with an
absorption mininum at 7700 km/s, and photospheric velocity of 3500 km/s as
measured from Fe II 501.8-nm.  The spectrum is consistent with that of a
typical type-IIP supernova at the end of the plateau phase.


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                         (C) Copyright 2013 CBAT
2013 March 24                    (CBET 3444)              Daniel W. E. Green