[IAUC] CBET 3434: 20130307 : SUPERNOVA 2013aj IN NGC 5339 = PSN J13540068-0755438

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                                                  Electronic Telegram No. 3434
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.
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Prepared using the Tamkin Foundation Computer Network


SUPERNOVA 2013aj IN NGC 5339 = PSN J13540068-0755438
     Giancarlo Cortini, Predappio, Italy, reports his discovery of an apparent
supernova (mag 14.7) on several unfiltered images (limiting mag about 19.5)
taken on Mar. 3.141 UT with a 0.35-m f/5.5 Schmidt-Cassegrain reflector (+
SXVR-H9 CCD camera).  The new object is located at R.A. = 13h54m00s.68, Decl.
= -7d55'43".8 (equinox 2000.0), which is 6" east and 8" north of the center
of NGC 5339.  Nothing is visible at this positoin on red and blue Palomar Sky
Survey plates (no dates or limiting magnitudes provided).  The variable was
designated PSN J13540068-0755438 when it was posted at the Central Bureau's
TOCP webpage and is here designated SN 2013aj based on the spectroscopic
confirmation reported below.  Additional CCD magnitudes for 2013aj (unfiltered
unless noted otherwise):  2012 May 17.90, [19.0 (Cortini); 2013 Mar. 3.141,
14.6 (J. Brimacombe, Cairns, Australia; remotely with a 51-cm RCOS telescope +
STL11K camera + luminance filter at the New Mexico Skies observatory near
Mayhill, NM, U.S.A.; position end figures 00s.66, 44".1; image posted at
website URL http://www.flickr.com/photos/43846774@N02/8526265048/); 4.055,
14.5 (Federica Luppi and Luca Buzzi, Varese, Italy; 0.38-m f/6.8 reflector;
position end figures 00s.63, 43".4; reference stars from CMC-14 catalogue;
image posted at URL http://www.astrogeo.va.it/pub/TOCP/PSN_N5339.jpg).

     Jujia Zhang and Changjun Wang, Yunnan Astronomical Observatory (YNAO);
and Xulin Zhao and Xiaofeng Wang, Tsinghua University, report on an optical
spectrogram (range 350-870 nm) of PSN J13540068-0755438 = SN 2013aj that was
obtained on Mar. 4.87 UT with the 2.4-m telescope (+ YFOSC) at the LiJiang
Gaomeigu Station of the YNAO.  The spectrum is consistent with a type-Ia
supernova a few days before maximum light.  Cross-correlation with a library
of supernova spectra using the "Supernova Identification" code (SNID; Blondin
and Tonry 2007, Ap.J. 666, 1024) shows that 2013aj matches with SN 2002er at
-5 days.  A weak absorption feature, perhaps due to C II 658.0-nm, can be
detected at around 632.0 nm.  Adopting a recession velocity of 2736 km/s
(Theureau et al. 1998, A.Ap. Suppl. 130, 333) for the host galaxy, NGC 5339,
they measure the velocity of the Si II 635.5-nm absorption feature to be
about 11400 km/s.

     Cosimo Inserra, Morgan Fraser, and Joe Polshaw, Queen's University,
Belfast; Nic Walton and Nadia Blagorodnova, Institute of Astronomy, Cambridge;
Matt Nichol, Queen's University, Belfast; S. Benetti and A. Pastorello,
Istituto Nazionale di Astrofisica, Padova Astronomical Observatory; S.
Valenti, Las Cumbres Observatory Global Telescope and University of California
at Santa Barbara; S. Taubenberger, Max-Planck-Institut fuer Astrophysik,
Garching; S. J. Smartt, K. Smith, and D. Young, Queen's University, Belfast;
M. Sullivan, University of Southampton; and A. Gal-Yam and O. Yaron, Weizmann
Institute for Science, on behalf of the PESSTO collaboration (www.pessto.org),
report that they obtained a spectrum of PSN J13540068-0755438 = SN 2013aj on
Mar. 3 using the European Southern Observatory's New Technology Telescope (+
EFOSC2 with Grism#13) at La Silla.  The spectrum is consistent with a young
type-Ia supernova in NGC 5339.  An excellent match is obtained with several
type-Ia supernovae about one week before B-band maximum light.  The
classification was 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 March 7                     (CBET 3434)              Daniel W. E. Green