[IAUC] CBET 3834: 20140322 : SUPERNOVA 2014ag IN MCG +07-34-101

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                                                  Electronic Telegram No. 3834
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 2014ag IN MCG +07-34-101
     V. Lipunov reports the discovery by Oleg Gress of an apparent supernova
(mag 15.5) on unfiltered CCD images (limiting mag 17.9) obtained with the
MASTER-Tunka auto-detection system (double 0.40-m f/2.5 reflector) on Mar.
11.79 UT.  The new object is located at R.A. = 16h30m40s.68, Decl. =
+44d30'34".7 (equinox 2000.0), which is 7" west and 14" south of the center of
the galaxy PGC 58391 = MCG +07-34-101.  D. Denisenko and E. Gorbovskoy add
that nothing is visible at this position on MASTER-Tunka archival images taken
on 2011 Aug. 16.6 (limiting mag 18.6).  The discovery and reference images
are posted at URL http://master.sai.msu.ru/static/OT/163040.68443034.7.png.
This variable is designated SN 2014ag based on the spectroscopic confirmation
detailed below.

     P. Ochner, S. Benetti, L. Tomasella, E. Cappellaro, A. Pastorello, N.
Elias-Rosa, and M. Turatto, Osservatorio Astronomico di Padova, Istituto
Nazionale di Astrofisica, report that an optical spectrogram (range 335-790
nm; resolution 0.8 nm) of 2014ag, obtained on Mar. 18.04 UT with the Asiago
1.22-m Galileo Telescope (+ Boller & Chivens spectrograph), shows it to be a
type-Ia supernova.  Adopting for the host galaxy (PGC 58391 = CGCG 224-62) a
radial velocity of 9496 km/s (Rines et al. 2002, A.J. 124, 1266; via NED), a
good match is found with several type-Ia supernovae about a week after maximum
light.  The expansion velocity deduced from the Si II 635.5-nm absorption is
about 11500 km/s.  The Asiago classification spectra are posted at website URL
http://sngroup.oapd.inaf.it; classification was made via GELATO (Harutyunyan
et al. 2008, A.Ap. 488, 383) and SNID (Blondin and Tonry 2007, Ap.J. 666,
1024).

     Maria Drout, Edo Berger, Chris Faesi, Allyson Bieryla, Adam Atanas,
Kristin Barclay, Tai Boon Ding, Sam Horan, McKenna Kardish, Tom Leith, Victor
Mata, Chris Merchantz, Max Murphy, and Sophie Welsh, Harvard University,
obtained a low-resolution optical spectrum of 2014ag on Mar. 19.5 UT using the
FAST spectrograph mounted on the F. L. Whipple Observatory (FLWO) 1.5-m
telescope as part of the Astronomy 100 undergraduate course.  Cross-
correlation with a library of supernova spectra using the "Supernova
Identification" code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024) shows
matches with normal type-Ia events approximately one week after maximum light.
The best match is with SN 2008Z at ten days post-maximum.  After correcting
for the host-galaxy (MCG +07-34-101) redshift of z = 0.03168 (Rines et al.
2002, A.J. 124, 1266; via NED), the velocity of the minimum of the Si II
635.5-nm feature is estimated to be approximately -11000 km/s.


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                         (C) Copyright 2014 CBAT
2014 March 22                    (CBET 3834)              Daniel W. E. Green