[IAUC] CBET 2132: 20100119 : NOVAE IN M81

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                                                  Electronic Telegram No. 2132
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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NOVAE IN M81
     Kamil Hornoch, Astronomical Institute, Ondrejov; Jose Prieto, Carnegie
Observatories; and Rubab Khan and Ondrej Pejcha, Department of Astronomy,
Ohio State University, report their discovery of a nova in M81 on a co-added
600-s Sloan r' CCD frame taken by Prieto and Khan with RETROCAM on the 2.4-m
Hiltner telescope at MDM observatory on Jan. 10.364 UT.  The new object is
visible on single 60-s images used for the co-added image, and on the co-added
1200-s image taken by Prieto and Khan with the same instrumentation on Jan.
11.368.  Available Sloan r' magnitudes for the object, designated M81N
2010-01a, as measured by Hornoch:  Jan. 8.333, [23.4; 10.364, 21.2 +/- 0.15;
11.368, 20.2 +/- 0.1; 14.394, 20.2 +/- 0.1; 15.471, 20.6 +/- 0.1.  M81N
2010-01a is located at R.A. = 9h55m26s.22, Decl. = +69o06'18".9 (equinox
2000.0), which is 37".2 west and 143".8 north of the center of M81.  Nothing
is present at this position on numerous archive images from the 2.54-m Isaac
Newton Telescope, the 4.2-m William Herschel Telescope, the 4-m Mayall
telescope, and the 8.2-m Subaru telescope, down to limiting magnitudes as
faint as Sloan r' = 23.3, R = 23.4, and V = 23.8.  Low-resolution optical
spectroscopy (range 400-750 nm, resolution 1.4 nm) was obtained using the
Boller & Chivens CCD Spectrograph on the 2.4-m Hiltner telescope at MDM
Observatory; a low-S/N spectrogram of M81N 2010-01a, taken by Prieto and
Khan under poor seeing conditions on Jan. 15.37, exhibits a blue continuum
with strong H-alpha in emission and very faint H-beta.  The FWHM of H-alpha
is about 1700 km/s.  This confirms, that the object is classical nova in M81.
     Hornoch also measured additional Sloan r' magnitudes for recent novae
in the same galaxy (cf. CBETs 2051, 2063):  M81N 2009-11a, 2010 Jan. 11.368
UT, [22.7.  M81N 2009-11b, Jan. 8.333, 23.0 +/- 0.3; 11.368, 23.4 +/- 0.2.
M81N 2009-11c, Jan. 8.333, [23.0; 11.368, [23.1.


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                         (C) Copyright 2010 CBAT
2010 January 19                  (CBET 2132)              Daniel W. E. Green