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IAUC 7810: 2002ap; V2540 Oph = N Oph 2002; 2002ao

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                                                  Circular No. 7810
Central Bureau for Astronomical Telegrams
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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URL http://cfa-www.harvard.edu/iau/cbat.html  ISSN 0081-0304
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     S. Nakano, Sumoto, Japan, reports the discovery by Yoji
Hirose, Chigasaki, Kanagawa-ken, of an apparent supernova (V =
14.5) on five unfiltered CCD frames (limiting mag 17) taken on Jan.
29.398-29.501 UT with a 0.25-m f/6.3 Schmidt-Cassegrain reflector.
Hirose reported the new object as being 274" west and 93" south of
the center of M74 (= NGC 628).  Nothing was visible at this
location on his CCD frames taken on Jan. 3.  R. Kushida,
Yatsugatake South Base Observatory, reports the following precise
position (measured by Y. Kushida) for SN 2002ap from an unfiltered
CCD image taken on Jan. 30.382, with the star at mag 13.7:  R.A. =
1h36m23s.85, Decl. = +15o45'13".2 (equinox 2000.0), or 258" west
and 108" south of the center of M74.  No star is visible at this
position on Kushida's survey frames taken from 1994 to 2001 Dec. 18
(limiting mag 17-18).  W. Li, University of California, reports
that an image taken with the Katzman Automatic Imaging Telescope
(KAIT) on Jan. 29.2 showed the new object at mag 14.4.  Li also
measured position end figures for SN 2002ap:  23s.87, 13".0.  A
KAIT image taken on Jan. 25.2 showed nothing at this position
(limiting mag about 18.0).

     N. N. Samus, Institute of Astronomy, Moscow, informs us that
the designation V2540 Oph has been given to this nova (cf. IAUC
7808, 7809).

SUPERNOVA 2002ao IN UGC 9299
     A. Gal-Yam and O. Shemmer, Tel Aviv University, write:  "A
spectrum (range 400-780 nm) of SN 2002ao (IAUC 7809), obtained
under poor conditions with the Wise Observatory 1-m telescope (+
FOSC spectrograph) on Jan. 30 by J. Dann, shows a blue continuum
with broad features.  The Si II trough typical of type-Ia
supernovae is not present, neither is the strong He I line around
570 nm that is observed in type-Ib supernovae.  The object is bluer
than any of the spectra of type-Ic events that are available to us
(e.g., Filippenko 1997, Ann. Rev. A.Ap. 35, 309), so we think it
unlikely to be of that type.  The lack of a strong H-alpha emission
component (either broad or narrow) seems not to favor possible
identification of this supernova as of type II-P or IIn.  However,
we find that the observed spectrum is similar to a spectrum of the
type-IIb supernova 1996cb (Qiu et al. 1999, A.J. 117, 736) taken
two days prior to maximum light.  It therefore seems most likely
that SN 2002ao is of type IIb, observed close to peak brightness."

                      (C) Copyright 2002 CBAT
2002 January 30                (7810)            Daniel W. E. Green

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