[IAUC] CBET 3823: 20140310 : SUPERNOVA 2014aa IN NGC 3861 = PSN J11450358+1958254

Dom Mar 9 20:49:11 ART 2014

                                                  Electronic Telegram No. 3823
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 2014aa IN NGC 3861 = PSN J11450358+1958254
     Ron Arbour, South Wonston, Hants, U.K., reports the discovery of an
apparent supernova (mag 15.7) on an unfiltered CCD image (limiting mag about
19.0) taken on Mar. 7.991 UT using a 35-cm f/6 Schmidt-Cassegrain telescope (+
SXVF H9 camera) in the course of his supernova patrol.  The new object is
located at R.A. = 11h45m03s.58, Decl. = +19d58'25".4 (equinox 2000.), which is
4" due west of the galaxy NGC 3861.  Nothing is visible at this position on
the Digitized Sky Survey blue (1986 Mar. 3) and red (1992 Apr. 28) plates from
the Palomar Sky Surey.  The variable was designated PSN J11450358+1958254 when
it was posted at the Central Bureau's TOCP webpage and is here designated SN
2014aa based on the spectroscopic confirmation reported below.  Additional CCD
magnitudes for 2014aa:  Mar. 9.004, 15.7 (Gianluca Masi, Francesca Nocentini,
and Patrick Schmeer; remotely using a 43-cm f/6.8 corrected Dall-Kirkham
robotic telescope near Ceccano, Italy; position end figures 03s.53, 25".1);
9.021, 15.2 (Giancarlo Cortini, Predappio, Italy; 0.35-m Schmidt-Cassegrain
telescope + SXVR H-9 camera; limiting mag 19.0).

     L. Tomasella, S. Benetti, E. Cappellaro, N. Elias-Rosa, P. Ochner, A.
Pastorello, and M. Turatto, Osservatorio Astronomico di Padova, Istituto
Nazionale di Astrofisica, report that an optical spectrogram (range 340-820
nm; resolution 1.3 nm) of PSN J11450358+1958254 = SN 2014aa, obtained on Mar.
8.99 UT with the Asiago 1.82-m Copernico Telescope (+ AFOSC), shows it to be
a type-Ia supernova.  Adopting for the host galaxy (NGC 3861) the redshift z =
0.01698 (Cortese et al. 2008, MNRAS 383, 1519; via NED), a good match is found
with several type-Ia supernovae about one week before B-band maximum light.
An expansion velocity of about 13900 km/s is derived from the minimum of the
Si II 635-nm line.  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).

     N. Blagorodnova, N. Walton, and M. Fraser, Institute of Astronomy; M.
Dennefeld, Institut Astrophysique de Paris; S. Taubenberger, Max-Planck-
Institut fuer Astrophysik, Garching; S. Benetti and A. Pastorello,
Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica (INAF);
C. Inserra, S. Smartt, K. Smith, and D. Young, Queen's University, Belfast; M.
Sullivan, University of Southampton; S. Valenti, Las Cumbres Observatory
Global Telescope; O. Yaron and A. Gal-Yam, Weizmann Institute for Science; C.
Knapic, R. Smareglia, and M. Molinaro, Trieste Astronomical Observatory, INAF;
and I. Manulis, Weizmann Institute for Science, report that a spectrogram
(range 398.5-931.5 nm; resolution 1.8 nm) of PSN J11450358+1958254 = SN
2014aa was obtained on Mar. 8 with the 3.6-m New Technology Telescope (+
EFOSC2 and Grism 13) at La Silla.  Cross-correlating the spectrum with a
library of supernovae template spectra using SNID (Blondin and Tonry 2007,
Ap.J. 666, 1024), good matches are found to a range of normal type-Ia
supernovae at the redshift of NGC 3861 (z = 0.017), a few days before maximum
light.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
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                         (C) Copyright 2014 CBAT
2014 March 10                    (CBET 3823)              Daniel W. E. Green