Electronic Telegram No. 4093
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@eps.harvard.edu (alternate cbat@iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


SUPERNOVA 2015H IN NGC 3464 = PSN J10544216-2104138
     S. Parker, Canterbury, New Zealand, reports the discovery of an apparent
supernova (red mag 16.9) on a 30-s unfiltered CCD image (limiting mag 19)
taken on Feb. 10.545 UT with a 35-cm Celestron C14 reflector (+ ST10 camera)
at his Parkdale Observatory in the course of the Backyard Observatory
Supernova Search.  The new object is located at R.A. = 10h54m42s.16, Decl. =
-21d04'13".8 (equinox 2000.0; reference stars from USNO-B and UCAC4
catalogues), which is 30" east and 14" south of the nucleus of the galaxy
NGC 3464.  Nothing is visible at this position on Digitized Sky Survey red
and infrared images (limiting red magnitude > 19).  An image of the variable
can be viewed via website URL http://tinyurl.com/q9n8jyw.  The variable was
designated PSN J10544216-2104138 when it was posted at the Central Bureau's
TOCP webpage and is here designated SN 2015H based on the spectroscopic
confirmation reported below.  The type-I supernovae 2002J (cf. IAUC 7800) and
2002hy (cf. IAUC 8016) also appeared in NGC 3464.  G. Masi writes that he
obtained unfiltered exposures of 2015H remotely using a 43-cm telescope at
Ceccano, Italy, on Mar. 22.90 that show the variable at red mag 18.1, with
position end figures 42s.14, 13".8.

     P. Zelaya-Garcia, Pontificia Universidad Catolica de Chile; S. Baumont
and A. Mitra, Laboratoire de Physique Nucleaire et de Hautes Energies, Paris;
P.-F. Leget, Laboratoire de Physique Corpusculaire de Clermont-Ferrand; N.
Chotard, Institut de Physique Nucleaire de Lyon; J. Anderson, European
Southern Observatory; N. Elias-Rosa, Instituto Nazionale di Astrofisica,
Osservatorio Astronomico di Padova; C. Inserra and R. Kotak, Queen's
University, Belfast; K. Maguire, European Southern Observatory (ESO); S.
Smartt and K. W. Smith, Queen's University, Belfast; M. Sullivan, Southampton
University; S. Taubenberger, ESO: S. Valenti, Las Cumbres Observatory Global
Telescope Network; O. Yaron, Weizmann Institute for Science; D. Young, Queen's
University, Belfast; I. Manulis, Weizmann Institute for Science; and F. Yuan,
Australian National University -- on behalf of the "Public European Southern
Observatory Spectroscopic Survey for Transient Objects" collaboration (cf. URL
http://www.pessto.org) -- report that an optical spectrogram of PSN
10544216-2104138 = SN 2015H, obtained on Feb. 11 UT at the ESO 3.6-m New
Technology Telescope (+ EFOSC2 Grism 13; range 398.5-931.5 nm; 1.8-nm
resolution) at La Silla, shows it to be a peculiar type-Ia supernova.  The
best matches to this spectrum, as found via the "Supernova Identification"
code (SNID; Blondin and Tonry 2007, Ap.J. 666, 1024), are with post-maximum
spectra of SNe 2002cx and 2005cc.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2015 CBAT
2015 April 17                    (CBET 4093)              Daniel W. E. Green