[IAUC] CBET 3156: 20120629 : NOVA SAGITTARII 2012 No. 3 = PNV J17522579-2126215

Vie Jun 29 15:43:19 ART 2012

                                                  Electronic Telegram No. 3156
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 SAGITTARII 2012 No. 3 = PNV J17522579-2126215
     Hitoshi Yamaoka, Kyushu University, reports the discovery by K. Itagaki
(Yamagata, Japan) of a possible nova (mag 10.3) on an unfiltered CCD image
taken on June 26.5494 UT with a 0.21-m reflector, the position given as R.A. =
17h52m25s.79, Decl. = -21d26'21".5 (equinox 2000.0); Itagaki confirmed the new
variable at mag about 10.2 on an unfiltered image taken on June 26.565 with a
0.60-m reflector.  Itagaki has posted an image of the variable at the following
website URL:  http://www.k-itagaki.jp/images/pnv.jpg.  The variable was
designated PSN J17522579-2126215 when it was posted at the Central Bureau's
TOCP webpage.
     Additional CCD magnitudes for PSN J17522579-2126215:  June 21.985, [12.0
(Herman Mikuz, Crni Vrh Observatory; 120-mm f/4 camera lens + CCD; object
position close to edge of field); June 22.988, [12.0 (Mikuz); June 24.050,
[12.0 (Mikuz); June 25.666, [16.0 (Itagaki); June 26.540, 9.9 (Yukio Sakurai,
Mito, Ibaraki-ken, Japan; independent discovery on four 20-s frames taken with
a Fuji FinePix S2 Digital Camera + Nikon 180-mm f/2.8 lens; position end
figures 25s.59, 22".9, measured by S. Nakano, Sumoto, Japan, who noted a
probable error of +/- 5" and limiting magnitude about 11.5); June 26.640, 10.0
(Itagaki); June 27.192, 9.0 (C. Jacques and E. Pimentel; using a 0.25-m f/3.4
astrograph + clear filter at the RAS Observatory near Mayhill, NM, U.S.A.;
position end figures 25s.79, 21".9; limiting mag 15.8; image posted at URL
http://ceamig-rea.net/tocp/PNV_J17522579-2126215.jpg); June 26.919, R = 9.7
(Mikuz); June 27.193, 9.9 (Jacques and Pimentel; red filter); June 27.194,
10.1 (Jacques and Pimentel; visual filter); June 27.195, 10.5 (Jacques and
Pimentel; blue filter); June 27.253, B = 11.2, V = 9.7, R_c = 8.7, I_c = 7.7
(T. Yusa, Osaki, Japan; position end figures 25s.77, 21".5, USNO-B1.0
reference stars; remotely using a 0.25-m f/3.4 hyperbolic astrograph + SBIG
ST-10XME camera at the RAS Observatory, iTelescope network, near Mayhill;
position and magnitude measured from a three co-added 30-s images, limiting
magnitude 15.7); June 27.3, R = 8.9 (Ernesto Guido, Giovanni Sostero, and
Nick Howes; remotely with a 0.10-m f/5 reflector of the ITelescope network
of the RAS Observatory near Mayhill; position end figures 25s.79, 21".6;
reference stars from CMC-14 catalogue; an animation showing a comparison
between their image and a red Digitized Sky Survey plate from 1996 is posted
at URL http://bit.ly/M3mhZn; their annotated confirmation image is posted at
URL http://bit.ly/OrjMA9); June 27.3101, V = 9.804 +/- 0.032 (Carl
Hergenrother, Lunar and Planetary Laboratory, University of Arizona; obtained
remotely with the Sierra Stars 0.61-m telescope; V and B magnitudes derived
from the AAVSO VPHOT program, while the R-band magnitudes were measured using
stars from the CMC-14 catalogue; position end figures 25s.79, 21".7, relative
to the CMC-14 astrometric catalogue); June 27.3129, B = 11.311 +/- 0.009
(Hergenrother); June 27.355, B = 11.36, V = 9.80, R_c = 8.82, I_c = 7.65
(Seiichiro Kiyota, Tsukuba, Japan; 25-cm reflector + SBIG ST-10XME CCD camera
located near Mayhill -- T4, iTelescope.net -- used for photometry; position
end figures 25s.69, 21".8; 43-cm reflector + FLI-PL6303E CCD camera -- T21 --
used for astrometry); June 28.3075, V = 11.019 +/- 0.046 (Hergenrother); June
28.3083, B = 12.282 +/- 0.024 (Hergenrother); June 28.3107, R = 9.62 +/- 0.06
(Hergenrother); June 28.612, I_c = 8.56 (Hiroyuki Maehara, Kwasan Observatory,
Kyoto University; 0.25-m telescope); June 28.613, R_c = 9.24 (Maehara); June
28.614, V = 11.24 (Maehara); June 28.616, B = 12.49 (Maehara).  Jacques and
Pimentel note that no progenitor star could be identified on a Palomar Sky
Survey plate from Sept. 1950.  Mikuz's June 26 image is posted at website URL
http://www.observatorij.org/vstars/PNVJ17522579-2126215.jpg; Yusa's image is
posted at http://space.geocities.jp/yusastar77/supernova/PSNinSgr_120627.htm.

     L. Kiss and K. Sarneczky, Konkoly Observatory, Hungary; and J. Kovacs and
T. Borkovits, ELTE Gothard Observatory, Hungary, report on a medium-resolution
optical spectrogram of PNV J17522579-2126215 obtained with the 0.5-m reflector
of the Gothard Observatory on June 26.95 UT.  The spectrum does not contain
any strong emission lines, with a clearly identifiable H-beta line in
absorption and a strong interstellar absorption of the sodium D doublet.  The
H-alpha line is possibly seen in absorption.  Two narrow emission lines are
also visible around 575.0 nm, each with FWZI about 60 km/s.  The spectrum
safely excludes the nova nature of the object, which is presumably a dwarf
nova in outburst phase.  The estimated visual brightness of the target was
about mag 9.5, based on the guider image.

     Kazuyoshi Imamura, Okayama University of Science (OUS), reports on
obtaining a low-resolution spectrum (R about 400) of PNV J17522579-2126215 on
June 28.593 UT, using the DSS-7 spectrometer attached to the 0.28-m
Schmidt-Cassegrain telescope at the OUS observatory.  Broad and prominent
emission lines of the Balmer series, He I (706.5-nm), O I (777.3-nm), and Mg
II (788.0-nm) can be seen in the spectrum.  The Balmer lines show asymmetrical
profiles; the FWHM of H-alpha is approximately 4100 km/s.  From this result,
the variable is thought to be a classical nova with a large expansion velocity.
The spectrum has been posted at the following website URL:
http://blog-imgs-44.fc2.com/t/n/b/tnblab/pnSGR_20120628.png.

     Hiroyuki Maehara, Kwasan Observatory, Kyoto University, obtained a
low-resolution spectrum (R about 300) of PNV J17522579-2126215 on June 28.647
with a 25-cm telescope at Kwasan Observatory.  The spectrum shows broad H-alpha
emission line (FWHM about 4000 km/s), which suggests that the object is a
classical nova.  The spectrogram has been posted at the following website URL:
http://www.kwasan.kyoto-u.ac.jp/~maehara/novae/pnv1752.png.

     Christian Buil writes that a spectrogram taken on June 28.864 UT with a
0.28-m telescope (+ LISA spectrograph) at the Castanet Observatory in France
reveals that the nova-like nature of PNV J17522579-2126215 is confirmed; the
spectrum is dominated by intense hydrogen emission.  The H_alpha line shows
a FWHM of 4500 km/s.

     Ulisse Munari, Istituto Nazionale di Astrofisica, Padova Astronomical
Observatory, observed PNV J17522579-2126215 with the 1.22-m Asiago telescope
(operated by the Department of Physics and Astronomy of the University of
Padova) on June 28.95 UT (presumed), at a dispersion on 0.231 micron/pixel
over the wavelength range 330-770 nm.  The spectrum is that of a nova of the
He/N type, with hydrogen Balmer and He I in strong emission.  The FWHM of the
emission lines is 4500 km/s.  The object appears to be heavily reddened, with
strong interstellar Na I lines visible in absorption.


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                         (C) Copyright 2012 CBAT
2012 June 29                     (CBET 3156)              Daniel W. E. Green