[IAUC] CBET 4059: 20150125 : SUPERNOVA 2014ef IN NGC 309 = PSN J00563965-0954028

Dom Ene 25 04:38:00 ART 2015

                                                  Electronic Telegram No. 4059
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 2014ef IN NGC 309 = PSN J00563965-0954028
     S. Nakano, Sumoto, Japan, reports the discovery by K. Itagaki (Teppo-cho,
Yamagata, Japan) of an apparent supernova (mag 17.9) in NGC 309 on an
unfiltered CCD frame (limiting mag 19.5) taken on 2014 Dec. 13.519 UT using a
0.50-m f/6.8 reflector remotely at the Takanezawa station, Tochigi-ken.  The
new object is located at R.A. = 0h56m39s.65, Decl. = -9d54'02".8 (equinox
2000.0; reference stars from UCAC4 catalogue), which is 44".3 west and 47".0
north of the nucleus of NGC 309 (position end figures 42s.65, 49".8).  Itagaki
posted his discovery image at website URL http://k-itagaki.jp/images/309.jpg.
The variable was designated PSN J00563965-0954028 when it was posted at the
Central Bureau's TOCP webpage and is here designated SN 2014ef based on the
spectroscopic confirmation reported below.  Additional CCD magnitudes for
2014ef:  2006 Aug. 30.654, [19.0 (Itagaki, 0.60-m f/5.7 reflector at
Yamagata); 2014 Nov. 22.489, [18.5 (Itagaki); Dec. 13.585, 18.2 (T. Noguchi,
Katori, Chiba-ken, Japan; 0.23-m f/6.3 Schmidt-Cassegrain reflector + FLI
ML0261E camera; position end figures 39s.67, 03".3; image posted at website
URL http://park8.wakwak.com/~ngc/images/PSNinNGC309.jpg; communicated by
Nakano); 14.432, V = 17.74, I_c = 17.40 (S. Kiyota, Kamagaya, Japan; remotely
with an iTelescope 0.5-m CDK astrograph + FLI PL-9000 CCD camera at Siding
Spring); 14.468, 17.9 (T. Yusa and N. Wada, Osaki, Japan; 0.30-m reflector;
position end figures 39s.63, 02".6; limiting mag 18.5; image posted at website
URL http://space.geocities.jp/yusastar77/supernova/PSNinNGC309_141214.htm);
17.888, 18.0 (G. Masi and P. Catalano; remotely using a 43-cm telescope at
Ceccano, Italy; position end figures 39s.65, 03".6); 18.521, 17.9 (F.
Watanabe, Nayoro, Japan; 0.50-m f/9.5 reflector + SBIG STL-1001E camera;
position end figures 39s.68, 02".5); 20.154, 17.9 (A. Valvasori and F.
Briganti; remotely using the iTelescope T21 Dall-Kirkham 43.1-cm f/4.5 reflector
near Mayhill, NM, U.S.A.).

     Y. Cao, California Institute of Technology; M. Kasliwal, Carnegie
Institution for Science, Pasadena, and Princeton University; Y. AlSayyad,
University of Washington; and S. R. Kulkarni, California Institute of
Technology, report spectroscopic classification of PSN J00563965-0954028 =
SN 2014ef with the Dual Imaging Spectrograph mounted on the ARC 3.5-m
telescope at the Apache Point Observatory on 2014 Dec. 16 UT.  The Superfit
software (Howell et al. 2005, Ap.J. 634, 1190) finds that the spectrum of
2014ef matches that of the type-Ib/c supernova 1999ex a few days after peak,
thus determining the redshift of 2014ef to be 0.02.  At this redshift, they
see no hydrogen line in the spectrum but identify He I 587.6-, 667.8-, and
706.5-nm with their minima at an expansion velocity of 6000 km/s.  Therefore,
they classify 2014ef as a type-Ib supernova at redshift 0.02.


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                         (C) Copyright 2015 CBAT
2015 January 25                  (CBET 4059)              Daniel W. E. Green