[IAUC] CBET 4163: 20151108 : NOVA SAGITTARII 2015 No. 4 = PNV J18225925-1914148

Dom Nov 8 02:38:47 ART 2015

                                                  Electronic Telegram No. 4163
Central Bureau for Astronomical Telegrams
Mailing address:  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 2015 No. 4 = PNV J18225925-1914148
[Editor's note:  this text replaces that on CBET 4159 (Ayani paragraph
corrected)]
     I. Endoh, National Astronomical Observatory of Japan, Mitaka, Tokyo,
forwarded to the Central Bureau on Oct. 31 the discovery by Shigehisa
Fujikawa (Kan'onji, Kagawa, Japan) of a variable star (mag 11.8) on a 60-s
CCD frame taken on Oct. 31.386 UT using a Minolta f/3.5 120-mm-f.l. camera
lens (+ BITRAN BN-51LN camera); the position of the variable was given as
R.A. = 18h22m59s.33, Decl. = -19d14'06".8 (equinox 2000.0).  A follow-up
30-s exposure by Fujikawa from a frame taken with a 400-mm-f.l. lens on
Oct. 31.406 yeilded mag 11.7 and position end figures 59s.29, 12".3.  Not
knowing of Fujikawa's discovery or Endoh's report, S. Nakano (Sumoto,
Japan) reported to the Bureau, two hours later, the independent discovery
of this variable as a nova-like object of mag 11.5 by Hideo Nishimura
(Kakegawa, Shizuoka-ken, Japan) from four 30-s frames (limiting magnitude
about 13) taken on Oct. 31.376 using a 200-mm.-f.l. f/3.2 lens with a Canon
EOS 5D digital camera, the position end figures given as 59s.25, 14".8 (and
when Nakano posted this to the Bureau's TOCP webpage, it was this position
that was used to automatically assign the designation PNV J18225925-1914148).
At the same time, Nakano added that Minoru Yamamoto (Okazaki, Aichi-ken,
Japan) reported his independent discovery of this object at mag 11.0 on three
frames taken on Oct.31.392 using a 135-mm-f.l. f/3.5 lens with a Canon EOS 5D
digital camera, providing position end figures 59s.10, 15" (uncertainty +/-
5").  The discovery image by Nishimura was posted at the following webiste
URL:  http://www.oaa.gr.jp/~oaacs/image/PNinSgr20151031.jpg.  Additional CCD
magnitudes for PNV J18225925-1914148:  Oct. 25.382, [11: (Yamamoto); 28.387,
[12.7 (Nishimura); 31.706, 11.3 (G. Masi; remotely using a 43-cm telescope at
Ceccano, Italy; position end figures 59s.29, 12".8); Nov. 1.053, B = 14.30,
V = 12.96, R_c = 11.63 and I_c = 10.28 (S. Kiyota, Kamagaya, Japan; remotely
with an iTelescope 0.50-m CDK astrograph near Mayhill, NM, USA; image posted
at URL http://meineko.sakura.ne.jp/ccd/PNV_J18225925-1914148.jpg); 1.373,
11.8 (T. Noguchi, Katori, Chiba-ken, Japan; 0.23-m f/6.3 Schmidt-Cassegrain
reflector; position end figures 59s.29, 12".4; communicated by Nakano; image
posted at URL http://park8.wakwak.com/~ngc/images/PNVinSgr_20151101.jpg).
P. Schmeer notes that a catalogued star (USNO-B1.0 0707-0560364; red mag
19.7-21.4) has position end figures 59s.341, 11s.60).

     K. Ayani, Bisei Astronomical Observatory, forwards a report by M. Fujii
(Kurashiki, Okayama, Japan), who obtained spectrograms (R about 500 at H-beta)
of PNV J18225925-1914148 on Nov. 2.417 and 3.389 UT with a 0.4-m telescope,
finding a strong and broad H-alpha emission line, an H-beta emission line,
He I (501.6-, 587.6-, and 706.5-nm) emission lines, and an N II (567.9-nm)
emission line on both nights.  The FWHMs of the H-alpha line, measured by
Gaussian fitting, are 4800 km/s on Nov. 2 and 4200 km/s on Nov. 3.  Fujii's
spectra are posted at URL http://otobs.org/FBO/etc/pnv_j18225925-1914148.htm.

     U. Munari, Istituto Nazionale di Astrofisica, Padova Astronomical
Observatory; and U. Sollecchia, Asiago Novae and Symbiotic Stars (ANS)
collaboration, report that on Nov 2.758 UT they obtained a long-exposure,
low-resolution spectrogram of PNV J18225925-1914148 with an Alpy 600
spectrograph mounted on a 20-cm Celestron C8 telescope at L'Aquila, Italy.
The object shows a feable red continuum superimposed with a very broad
H-alpha feature in emission, with a nearly Gaussian profile characterized by
FWHM = 5100 km/s, which suggests the transient to be a nova.  Munari adds
that he also obtained a low-resolution spectrogram (range 330-780 nm; 0.23
nm/pixel) of PNV 18225925-1914148 on Nov 3.718 with the Asiago 1.22-m
telescope.  The spectrum shows strong emission lines of hydrogen Balmer,
He I (501.6-, 587.6, and 706.5-nm), and N II (465.1- and 568.0-nm),
appearing on top of a highly reddened continuum; their FWHM is measured to
be 4000 km/s, causing He I 667.8-nm to be overwhelmed by the H-alpha red
wing.  The object has the typical spectrum of a He/N nova.


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

                         (C) Copyright 2015 CBAT
2015 November 8                  (CBET 4163)              Daniel W. E. Green