[IAUC] CBET 1535: 20081010 : DWARF NOVA IN DRACO

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                                                  Electronic Telegram No. 1535
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
M.S. 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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DWARF NOVA IN DRACO
     H. Yamaoka, Kyushu University, reports the discovery by K. Itagaki
(Yamagata, Japan) of a previously unknown dwarf nova on his survey CCD image
taken on Oct. 2.533 UT with a 0.21-m reflector.  An image taken on Oct. 2.539
with a 0.60-m reflector shows the variable at mag about 14.9 and located at
R.A. = 19h14m43s.55, Decl, = +60d52'13".9 (equinox 2000.0).  Nothing is
visible at this position on Itagaki's survey image from June 12.597 (limiting
mag 17.5) or on the Digitized Sky Survey from 1991 Aug. 30 (F) and 1992 June
28 (J) to limiting mag about 21.  A very faint object is present near the
reported position in the USNO-B1.0 catalogue (position end figures 43s.39,
14".4, mag 21) and GSC 2.3 catalogue (position end figures 43s.46, 14".3, mag
20.2-21.0).  Yamaoka adds that photometry by H. Maehara shows a short-period
(1-2 hr) modulation with amplitude about 0.2 mag.  S. Nakano (Sumoto, Japan)
reports the following additional magnitudes by Itagaki:  Oct. 3.387, 15.0;
9.522, 15.6.
     Following posting on the Central Bureau's unconfirmed-objects webpage,
L. Buzzi (Varese, Italy) reports that his unfiltered CCD image taken with a
60-cm reflector on (presumably) Oct. 5 shows the variable at mag 14.7 and
position end figures 43s.51, 14".3.  Buzzi also measures red mag 18.2 and
position end figures 43s.42, 14".9 from a Palomar Sky Survey (POSS) image
taken on 1991 Aug. 30.175 UT, and position end figures 43s.39, 14".7 from
a POSS photograph taken on 1993 July 1.332.  A. Oksanen, Muurame, Finland,
writes that the variable appeared at mag 15.3 with a smooth 0.2-mag
variation on presumed-V-band images taken on Oct. 8, also measuring
position end figures 43s.57, 14".1; he has posted an image of the variable
at http://murtoinen.dyndns.org/ccd/VarDra2008/VarDra2008_20081008C.jpg.
R. A. Koff (Bennett, CO, U.S.A.) also reports a photometric amplitude
of about 0.2 mag, with average mag 15.6 and position end figures 43s.53,
13".9 on Oct. 8/9.


NOTE: These 'Central Bureau Electronic Telegrams' are sometimes
      superseded by text appearing later in the printed IAU Circulars.

                         (C) Copyright 2008 CBAT
2008 October 10                  (CBET 1535)              Daniel W. E. Green