[IAUC] CBET 2731: 20110530 : DWARF NOVA IN PEGASUS (PNV J21095047+1348396)

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                                                  Electronic Telegram No. 2731
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
CBAT Director:  Daniel W. E. Green; Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
e-mail:  cbatiau en eps.harvard.edu (alternate cbat en iau.org)
URL http://www.cbat.eps.harvard.edu/index.html
Prepared using the Tamkin Foundation Computer Network


DWARF NOVA IN PEGASUS (PNV J21095047+1348396)
     H. Yamaoka, Kyushu University, forwards the discovery by K. Itagaki
(Yamagata, Japan) of a possible nova on May 24.672 UT during a survey program
performed by himself and H. Kaneda (Hokkaido, Japan).  The variable, which
was designated PNV J21095047+1348396 when posted on the Central Bureau's TOCP
webpage, was confirmed at unfiltered CCD mag about 11.5 by Itagaki with a
0.60-m reflector on May 24.699, the position measured to be R.A. =
21h09m50s.47, Decl. = +13d48'39".6 (equinox 2000.0); Itagaki has posted his
confirmation image at website URL http://www.k-itagaki.jp/images/pnv.jpg.
Additional approximate magnitudes for PNV J21095047+1348396 (unfiltered CCD
unless noted otherwise):  May 17.71, [14.9 (Itagaki, 0.21-m reflector); May
18.76, [12.3 (Itagaki, 180-mm-f.l. telephoto lens); May 25.3, 11.0 (Ernesto
Guido and Giovanni Sostero; remotely with a 0.25-m f/3.4 reflector at the GRAS
Observatory near Mayhill, NM, U.S.A.; position end figures 50s.46, 39".6,
which they also note to be very close to a star of red mag 18.8 in the USNO-
B1.0 catalogue; their image compared to a red Digitized Sky Survey plate from
1991 is posted at website URL http://bit.ly/mycwOt); May 25.676, 11.6 (K.
Kadota, Ageo, Japan; 0.25-m f/5 reflector + SBIG ST-9E camera; position end
figures 50s.47, 39".7; communicated by S. Nakano, Sumoto, Japan; image posted
at URL http://members.jcom.home.ne.jp/kenic-k/image/PNVinPeg-20110525.jpg);
May 26.076, 11.5 (P. Schmeer, Bischmisheim, Germany; visual).  Itagaki/Yamaoka
note also that a faint star (mag about 19) is located within several arcsec of
Itagaki's position in the USNO-B1.0 catalogue (position end figures 50s.427,
39".95).

     Akira Arai, Koyama Astronomical Observatory, Kyoto Sangyo University,
writes that optical low-dispersion spectroscopic observations (range 400-750
nm; R about 600 at H-alpha) of PNV J21095047+1348396 were made on May 25.67 UT
using the 1.3-m Araki telescope (+ LOSA/F2).  The spectrum shows a blue
continuum with H_beta and H_gamma absorptions and no significant blue-shifts.
No obvious line is visible at H_alpha.  These suggest that an emission
component of H_alpha could be filling in the absorption line and that the
object is a dwarf nova in outburst.  Their spectrum has been posted at website
URL http://www.cc.kyoto-su.ac.jp/~kao/blog/index.php/view/94.

     D. D. Balam, Dominion Astrophysical Observatory, National Research Council
of Canada (NRCC); M. L. Graham, Las Cumbres Observatory Global Telescope,
University of California at Santa Barbara; E. Y. Hsiao, Lawrence Berkeley
Laboratory; and D. W. E. Green, Harvard University, report that a spectrogram
(range 382-714 nm, resolution 0.3 nm) of PNV J21095047+1348396, obtained on
May 29.42 UT with the 1.82-m Plaskett Telescope of the NRCC, shows a steep
blue continuum with broad asymmetric Balmer absorption lines.  H-alpha
exhibits a broad absorption profile with a sharp (1.2-nm FWHM) central emission
spike.


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                         (C) Copyright 2011 CBAT
2011 May 30                      (CBET 2731)              Daniel W. E. Green