[IAUC] CBET 3724: 20131128 : NOVA SERPENTIS 2013 = PNV J18090346-1112345

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                                                  Electronic Telegram No. 3724
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 SERPENTIS 2013 = PNV J18090346-1112345
     Syuichi Nakano, Sumoto, Japan, reported the discovery by Koichi Itagaki
(Teppo-cho, Yamagata, Japan) of a possible nova (mag 12.3) on an unfiltered
CCD frame (limiting magnitude about 15) taken on Nov. 24.384 UT using a 0.21-m
f/3 reflector, confirmed on frames taken with a 0.50-m f/6 reflector; the new
object is located at R.A. = 18h09m03s.46, Decl. = -11d12'34".5 (equinox
2000.0).  Nothing is visible at this position on Itagaki's survey frame taken
on Nov. 6.375 (limiting mag about 15).  Itagaki has posted his discovery image
at website URL http://www.k-itagaki.jp/images/Ser.jpg.  The variable was
designated PNV J18090346-1112345 when it was posted at the Central Bureau's
TOCP webpage.  Additional CCD magnitudes for the variable, all communicated by
Nakano:  Nov. 22.370 and 23.361, [13 (Tadashi Kojima, Tsumagoi, Gunma-ken,
Japan; 150-mm f/2.8 lens + Canon EOS 60D digital camera); 26.369, 11.7
(Itagaki; 0.50-m f/6.8 reflector remotely at Takanezawa; position end figures
03s.42, 34".7; image posted at http://www.k-itagaki.jp/images/ser-2.jpg);
26.373, 12.7 (T. Kojima, Gunma-ken, Japan; 150-mm f/2.8 lens + Canon EOS 60D
camera).  Patrick Schmeer, Bischmisheim, Germany, notes that an apparent star
catalogued as UGPS J180903.43-111234.3 in the UKIDSS-DR6 Galactic Plane Survey
(Lucas et al. 2012) has position end figures 03s.433, 34".39 and H magnitude
20.9.

     Ulisse Munari, Astronomical Observatory of Padova, INAF; and Paolo
Valisa, ANS Collaboration, report that a low-resolution spectrogram (range
390-860 nm, 0.21 nm/pixel) of PNV J18090346-1112345 was obtained on Nov.
25.792 UT with the Varese 0.61-m telescope (+ Multi-Mode spectrograph).  The
spectrum has a low signal-to-noise ratio because the target was only briefly
observable very low on the horizon after sunset.  The spectrum is clearly that
of a nova with hydrogen Balmer lines and O I 777.2-nm, 844.6-nm in emission.
The FWHM of H_alpha is 1100 km/s, and the H_alpha/H_beta flux ratio is 25.
The O I 844.6-nm/777.2-nm flux ratio is 2.0.  A P-Cyg absorption component is
visible in O I 777.2-nm, blue-shifted by 1400 km/s with respect to the
emission component.  The slope of the continuum corresponds to a photometric
color of B-V = +0.6.

     R. Itoh, Y. Kanda, Y. Moritani, and K. S. Kawabata, Hiroshima University,
obtained a low-resolution optical spectrogram (range 400-950 nm) of PNV
J18090346-1112345 on Nov. 25.37 UT with the 1.5-m Kanata telescope (+ HOWPol)
at Higashi-Hiroshima Observatory.  The spectrum is consistent with a reddened,
post-maximum classical nova.  It shows strong emission lines of Balmer series
as well as O I 777.3-nm and the Ca II infrared triplet.  The H-alpha line has
an equivalent width of about -37 nm and a FWHM of about 900 km/s, and no
significant absorption component is seen with the Balmer lines.  On the other
hand, a weak, blue-shifted absorption component (-1400 km/s) is associated
with the O I 777.3-nm emission line.


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                         (C) Copyright 2013 CBAT
2013 November 28                 (CBET 3724)              Daniel W. E. Green