[IAUC] CBET 2760: 20110705 : SUPERNOVA 2011dy IN UGC 12628 = PSN J23292013+0323086

[quai en eps.harvard.edu]

                                                  Electronic Telegram No. 2760
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 2011dy IN UGC 12628 = PSN J23292013+0323086
     E. Briggs, J. Newton, and T. Puckett report the discovery of an apparent
supernova (mag 16.8) on an unfiltered CCD image (limiting mag 18.9) taken with
a 0.40-m reflector at Portal, AZ, U.S.A., on June 28.4428 UT in the course of
the Puckett Observatory Supernova Search.  The new object, which was confirmed
at mag 16.5 on June 29.3910 by E. Guido and G. Sostero with the GRAS
Observatory 0.25-m reflector near Mayhill, NM, U.S.A., is located at R.A. =
23h29m20s.13, Decl. = +3o23'08".6 (equinox 2000.0), which is 28".8 west and
15".8 south of the center of UGC 12628.  Nothing is visible at this position
on images taken by Puckett on June 3 (limiting mag 18.6).  The variable was
designated PSN J23292013+0323086 when posted on the Central Bureau's TOCP
webpage and is here designated SN 2011dy based on the spectroscopic
confirmation reported below.  A finder image is posted at the following
website URL:  http://possdata.com/PSNJ23292013+0323086.jpg.
     Additional CCD magnitudes for PSN J23292013+0323086 = SN 2011dy:  June
30.428 UT, 16.0 (S. Baroni, L. Buzzi, P. Concari, S. Foglia, G. Galli, and M.
Tombelli; remotely using a 0.21-m refractor + Bessel V filter at the Tzec Maun
Observatory near Mayhill, NM, U.S.A.; position end figures 20s.16, 08".5);
30.431, 16.2 (Joseph Brimacombe, Cairns, Australia; unfiltered image; position
end figures 20s.19, 08".7).  Brimacombe has posted his image at the following
website URL:  http://www.flickr.com/photos/43846774@N02/5889670968/.

     J. L. Prieto, Carnegie Observatories, reports that a spectrogram (range
380-920 nm; resolution 0.7 nm) of 2011dy was obtained on July 3 UT with WFCCD
mounted on the du Pont 2.5-m telescope at Las Campanas Observatory.  The
SNID cross-correlation software (Blondin and Tonry 2007, Ap.J. 666, 1024) was
used to aid identification and age/redshift estimation.  The spectrum of 2011dy
shows a very blue continuum and broad Balmer lines with P-Cyg profiles,
characteristic of young type-II supernovae.  SNID gives an age of 1-2 weeks
after explosion.  After correcting for the recession velocity of the host
galaxy, UGC 12628 (4679 km/s; Theureau et al. 1998, A.Ap. Suppl. 130, 333),
a blueshift of the H-alpha P-Cyg profile of 8000 km/s is measured.


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                         (C) Copyright 2011 CBAT
2011 July 5                      (CBET 2760)              Daniel W. E. Green