[IAUC] CBET 3397: 20130203 : NOVA CEPHEI 2013 = PNV J23080471+6046521

[quai en eps.harvard.edu]

                                                  Electronic Telegram No. 3397
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


NOVA CEPHEI 2013 = PNV J23080471+6046521
     Koichi Nishiyama, Kurume, Japan; and Fujio Kabashima, Miyaki, Japan,
report their discovery of a possible Milky Way nova (mag 10.3) on two 40-s
unfiltered CCD frames (limiting magnitude 13.5) taken around Feb. 2.4119 UT
using a 105-mm f/4 camera lens (+ SBIG STL6303E camera).  They confirmed the
object's presence on five 3-s unfiltered CCD frames (limiting magnitude 17.5)
taken around Feb 2.4327 using a Meade 200R 0.40-m f/9.8 reflector (+ SBIG
STL1001E camera).  The new variable is located at R.A. = 23h08m04s.71, Decl.
= +60d46'52".1 (equinox 2000.0).  Nothing is visible at this position on
their survey frames taken on Jan. 23.411 and 26.401 (limiting mag 13.6).
The variable was designated PNV J23080471+6046521 when it was posted at the
Central Bureau's TOCP webpage.  Additional CCD magnitudes for the variable:
Jan. 28.412, 11.9 (Nishiyama and Kabashima; pre-discovery; limiting mag
13.7); 28.458, [13.0 (Hiroyuki Maehara, Kiso Observatory, Institute of
Astronomy, University of Tokyo; archival survey images of the Kyoto/Kiso
Wide-field Survey (105-mm f/2.0 lens + SBIG ST-8XME camera + Bessell V
filter); 30.392, V = 11.97 (Maehara; pre-discovery); 30.413, 11.0 (Nishiyama
and Kabashima; pre-discovery; limiting mag 13.5); 31.389, V = 11.45 (Maehara;
pre-discovery); 31.390, V = 11.27 +/- 0.07 (Maehara; limiting mag about 13.5);
Feb. 2.536, V = 11.64, R_c = 10.96 (Seiichiro Kiyota, Tsukuba, Japan;
remotely with a 0.50-m f/6.8 astrograph + FLI ProLine PL11002M camera of
iTelescope.NET near Mayhill, NM, USA; low altitude; image posted at website
URL http://meineko.sakura.ne.jp/ccd/PN_J23080471+6046521.jpg); 2.568, V =
11.64 (Katsumi Yoshimoto, Yamaguchi, Japan; limiting mag 13.7; Nikon D5000
Digital camera + Nikon 180-mm f/2.8 lens; image posted at website URL
http://orange.zero.jp/k-yoshimoto/PNV%20J23080471+6046521.jpg); 2.8, 9.8
(Ernesto Guido and Nick Howes; remotely through a 0.43-m f/6.8 reflector of
the ITelescope network located at Nerpio, Spain; position end figures 04s.70,
52".0; reference stars from USNO-B1.0 catalogue; animation showing a
comparison between their and a Digitized Sky Survey red plate from 1991 is
posted at website URL http://bit.ly/Xfunxx, and an annotated image is posted
at http://bit.ly/11gmyju); 2.861, 10.9 (N. James, Chelmsford, Essex, England;
position end figures 04s.72, 51".7); 3.075, 10.6 (R. A. Koff, Bennett, CO,
USA; 0.25-m reflector + Apogee U-47 camera; high clouds; limiting mag 16.3;
position end figures 04s.69, 51".6; UCAC3 reference stars; image posted at URL
http://antelopehillsobservatory.org/SNpictures/PNVJ23080471+6046521final.jpg;
1-hr lightcurve featureless within 0.01 magnitude resolution);

     Kazuyoshi Imamura, Okayama University of Science (OUS), writes that his
team has obtained a low-resolution spectrogram (R about 400) of PNV
J23080471+6046521 on Feb. 2.526 UT using the DSS-7 spectrometer attached to
the 0.40-m Schmidt-Cassegrain telescope at the OUS observatory.  Emission
lines of Balmer series (FWHM of H-alpha about 1000 km/s), Fe II (74), and O I
(777.3 nm) can be seen in the spectrum.  H-alpha and O I lines show clearly a
P-Cyg profile.  The expansion velocity derived from these profiles is
approximately 1200 km/s.  From this result, the variable is thought to be a
classical nova of the "Fe II" class.  The spectrum has been posted at website
URL http://tnblab.blog7.fc2.com/blog-entry-361.html.

     Kazuya Ayani, Bisei Astronomical Observatory, reports that M. Fujii
(Kurashiki, Okayama, Japan) obtained a spectrogram (resolution R = 650 at
H_alpha) of PNV J23080471+6046521 on Feb. 2.495 UT with a 0.4-m telescope at
the Fujii Kurosaki Observatory and found that its H-alpha and H-beta emission
had P-Cyg profiles, the absorption bottom of the H-alpha profile being
blueshifted by 800 km/s with respect to the emission peak.  He also found
emission lines of Fe II (multiplets 42, 49, 74) and Na I D, noting that the
slope of the continuum indicates heavy interstellar reddening.  His spectrum
is posted at URL http://otobs.org/FBO/etc/pnv_cep_20130202.gif.  This
spectrogram shows that the new variable is a nova in early phase.


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

                         (C) Copyright 2013 CBAT
2013 February 3                  (CBET 3397)              Daniel W. E. Green