[IAUC] CBET 1632: 20081225 : APPARENT NOVA IN M81

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                                                  Electronic Telegram No. 1632
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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APPARENT NOVA IN M81
     M. M. Kasliwal, S. B. Cenko, R. Quimby, A. Rau, E. O. Ofek, and S. R.
Kulkarni, California Institute of Technology, report the discovery on a
CCD image taken with the Palomar 1.5-m reflector on Dec. 3.303 UT of an
optical transient (magnitude g = 20.5 +/- 0.1) located at R.A. = 9h55m16s.920,
Decl. = +69o02'17".68 (equinox 2000.0), which is 87" west and 97" south of
the nucleus of M81.  Nothing was visible to limiting g magnitude 22.3 on an
image taken in their "Palomar 60-inch Fast Transients In Nearby Galaxies"
survey on Nov. 30.410.  Follow-up spectroscopy with the Double Beam
Spectrograph on the Palomar Hale telescope showed a featureless spectrum on
Dec. 4 and 5.  Spectroscopy with the Gemini North telescope on Dec. 16
revealed prominent H-alpha and other emission features (e.g., Fe II, O I)
resembling an "Fe-class" classical nova.  Additional g-band magnitudes:
Dec. 6.301, 20.2; 10.280, 21.2.
     Kamil Hornoch, Ondrejov Observatory, reports his independent discovery
of this apparent nova on a co-added 3690-s unfiltered CCD frame taken with
the 0.65-m telescope at Ondrejov on Dec. 9.164 UT; the new object is not
visible on single 90-s images used for the co-added image.  Hornoch's
position for the nova is R.A. = 9h55m16s.79, Decl. = +69o02'17".4, which
is 88" west and 98" south of the center of M81.  Nothing is visible at
this position on numerous archive images taken at Ondrejov, including
limiting R-band magnitudes of 21.8-21.9 on Feb. 11.788 and Oct. 31.167.


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                         (C) Copyright 2008 CBAT
2008 December 25                 (CBET 1632)              Daniel W. E. Green