[IAUC] CBET 1191: 20080103 : SUPERNOVA 2007uy IN NGC 2770

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                                                  Electronic Telegram No. 1191
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVA 2007uy IN NGC 2770
     As first announced on IAUC 8908, S. Nakano, Sumoto, Japan, reports the
discovery of an apparent supernova (mag 17.2) by Yoji Hirose (Tsutsumi,
Chigasaki, Kanagawa-ken, Japan) on ten unfiltered CCD frames taken around
2007 Dec. 31.669 UT using a 0.35-m f/6.8 Schmidt-Cassegrain telescope
(limiting mag 18.0); Nakano has measured mag 17.0 and the following position
for the new object from a jpeg image supplied by Hirose:  R.A. = 9h09m35s.40,
Decl. = +33o07'09".9 (equinox 2000.0), which is 20".6 east and 15".5 south
of the center of NGC 2770.  Nothing is visible at this position on Hirose's
survey frames taken on 2007 Mar. 7 and Dec. 18 (limiting magnitude 18) or on
Digitized Sky Survey (DSS) imagery.  Hirose also reports mag 17.0 from a
25-s exposure on 2008 Jan. 1.595.  Nakano adds that K. Kadota (Ageo, Japan,
0.25-m f/5 reflector) reports mag 17.3 and position end figures 35s.27,
08".9 from an unfiltered CCD image taken on 2007 Dec. 31.786; Kadota adds
that there are condensed lumps (evidently H II regions) near 2007uy on red
DSS images from 1998 and 2000.  Nakano also writes that K. Itagaki
(Takanezawa station, Tochigi-ken, Japan, 0.30-reflector) obtained an
unfiltered CCD exposure on 2008 Jan. 1.651, showing 2007uy at mag 16.9 and
position end figures 35s.35, 08".9.  P. Corelli, Pagnacco, Italy, writes
that (following posting of this object on the Central Bureau's unconfirmed-
objects webpage) his four co-added 600-s CCD images of NGC 2770 taken on
2008 Jan. 1.885 with his 0.45-m f/4.5 reflector yield position end figures
35s.17, 08".9 (offset 15" east, 15" south of the galaxy nucleus) and mag
16.8; his comparison with a red Palomar Sky Survey image shows nothing at
this position (limiting mag presumed to be 20-21), despite the presence of
many H II regions.
     S. Blondin, Harvard-Smithsonian Center for Astrophysics (CfA), on
behalf of the CfA Supernova Group, reports that a spectrogram (range
350-740 nm) of 2007uy, obtained by M. Calkins on Jan. 3.40 UT with the
F. L. Whipple Observatory 1.5-m telescope (+ FAST), shows it to be a
type-Ib supernova before maximum light. Cross-correlation with a library
of supernova spectra using the "Supernova Identification" code (SNID;
Blondin and Tonry 2007, Ap.J. 666, 1024) indicates that 2007uy is most
similar to SN 2004gq (cf. IAUC 8452, 8461) at roughly one week before
maximum.
     The type-Ib supernova 1999eh also appeared in NGC 2770 (cf. IAUC 7282).


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                         (C) Copyright 2008 CBAT
2008 January 3                   (CBET 1191)              Daniel W. E. Green