Discovering party: Eagle Hill Supernova Search Project: Doug Rich, Thomas Harvey, Joseph Rosebush, and Charles Sawyer
Official CBAT name: SN 2013cd
Subcategory: type la
Location: Galaxy UGC 4294 in the Constellation Ursa Major
Distance: 500 Million Light Years from Earth
Coordinates and location in the sky
RA: 08h 16m 49s
Dec.: +60o 29′ 35″
Supernova SN 2013bl was discovered by the Eagle Hill Supernova Search Project led by Doug Rich. Team members Thomas Harvey, Charlie Sawyer and Joe Rosebush conducted the blink comparison that resulted in the discovery.
Spectroscopic analysis of the supernova was conducted by astronomer Andrea Pastorello and his team with the Italian National Institute for Astrophysics in Asiago, Italy. The supernova was then designated SN 2013cd by the Central Bureau for Astronomical Telegrams in Cambridge, Massachusetts.
- Supernova SN2013cd was the 81st supernova discovered in 2013.
Official CBAT Report
Electronic Telegram No. 3514
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: firstname.lastname@example.org (alternate email@example.com)
Prepared using the Tamkin Foundation Computer Network
SUPERNOVA 2013cd IN UGC 4294 = PSN J08164900+6029285
D. Rich, T. Harvey, J. Rosebush, and C. Sawyer report their discovery of
an apparent supernova (mag about 17.0) on unfiltered CCD frames (limiting mag
19.4) taken with a 0.41-m reflector on Apr. 28.061 UT in Hampden, ME, U.S.A,
in the course of the Eagle Hill Supernova Search Project. The new object is
located at R.A.= 8h16m49s.0, Decl. = +60o29’28″.5 (equinox 2000.0) which is
about 2″.3 west and 6″.4 south of the center of UGC 4294. Nothing is visible
at this position on Palomar Digital Sky Survey images from 1989 Dec. 21
(limiting red mag about 20.3) and 1990 Jan. 1 (limiting blue mag about 21.0).
The variable was designated PSN J08164900+6029285 when it was posted at the
Central Bureau’s TOCP webpage and is here designated SN 2013cd based on the
spectroscopic confirmation reported below. Additional CCD magnitudes for
2013cd: Mar. 10.050, [19.2 (Rich); Apr. 29.034, 16.8 (Rich et al.; limiting
mag 19.4); Apr. 29.331, 16.7 (Joseph Brimacombe, Cairns, Australia; remotely
using a a 51-cm RCOS telescope + STL11K camera + luminance filter at the New
Mexico Skies observatory near Mayhill, NM, U.S.A.; position end figures
49s.02, 28″.5; with an infrared filter and bandpass > 700 nm, mag 16.4; image
posted at website URL http://www.flickr.com/photos/43846774@N02/8694164315/);
30.148, 16.8 (Brimacombe; position end figures 48s.97, 28″.8; image posted at
website URL http://www.flickr.com/photos/43846774@N02/8705105421/).
P. Ochner, A. Pastorello, L. Tomasella, S. Benetti, E. Cappellaro, and M.
Turatto, Osservatorio Astronomico di Padova, Istituto Nazionale di Astrofisica,
report that an optical spectrogram (range 340-790 nm; resolution 0.9 nm),
obtained on May 5.02 UT with the Asiago 1.22-m Galileo Telescope (+ Boller &
Chivens spectrograph), shows that PSN J08164900+6029285 = SN 2013cd is a
reddened type-I supernova (most likely a type-Ia event). Adopting a
recessional velocity of 11716 km/s for the host galaxy (Huchra et al. 2012,
Ap.J. Suppl. 199, 26), an expansion velocity of about 11700 km/s is measured
from the minimum of the Si II 635-nm line. The Asiago classification spectra
are posted at website URL http://graspa.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).
Locating the Constellation Ursa Major in the Night Sky