Electronic Telegram No. 4334
Central Bureau for Astronomical Telegrams
Mailing address:  Hoffman Lab 209; Harvard University;
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Prepared using the Tamkin Foundation Computer Network


NEW NOVA IN SAGITTARIUS = PNV J18205200-2822100
     S. Nakano, Sumoto, Japan, reports the discovery of an apparent nova (mag
10.4) by Yukio Sakurai (Mito, Ibaraki-ken, Japan) on two 10-s digital
exposures taken on Oct. 26.380 UT with a 180-mm-focal-length f/2.8 camera
lens (+ Nikon D7100 camera); Sakurai measured the following position for the
variable:  R.A. = 18h20m52s.0, Decl. = -28d22'10" (equinox 2000.0).  He
adds that nothing is visible at this position on two frames taken on Oct.
23.398 using the same instrumentation.  The variable was designated PNV
J18205200-2822100 when it was posted at the Central Bureau's TOCP webpage.
Nakano measured Sakurai's jpeg image and found mag 10.7 and position end
figures 52s.42, 11".2 (estimating the positional uncertainty as +/- 2"
and addiing that the limiting magnitude seems to be 12.5.  He adds that
the closest star in the USNO-A2 catalogue appears to be one of mag 17.3
at position end figures 52s.65, 13".9.  The discovery image was posted at
website URL http://www.oaa.gr.jp/~oaacs/image/PNinSgr2.jpg.
     P. Schmeer, Bischmisheim, Germany, noted that an independent discovery
of PNV J18205200-2822100 was made by K. Z. Stanek et al. (cf. website URL
http://www.astronomerstelegram.org/?read=9669) in the course of the All-Sky
Automated Survey for Supernova (ASAS-SN) using the robotic 14-cm "Cassius"
telescope at Cerro Tololo, in which the variable appeared at V magnitude
about 13.7 on Oct. 25.02 (with position end figures 52s.12, 13".5).
     Additional CCD magnitudes for PNV J18205200-2822100:  Oct. 20.04 UT,
[17.3 (ASAS-SN); 26.02, 11.6 (ASAS-SN); 27.047, B = 11.04, V = 10.65, I_c =
10.18 (S. Kiyota, Kamagaya, Japan; remotely with a 0.50-m f/4.5 CDK astrograph
near Mayhill, NM, USA); 26.057, B = 11.76, V = 11.44 (S. O'Connor, St. George,
Bermuda; via E. O. Waagen, AAVSO).  Visual magnitudes forwarded by Waagen:
26.488, 11.0 (A. Pearce, Nedlands, W. Australia); 27.489, 10.6 (Pearce);
27.502, 10.4 (D. Benn, Klemzig, S. Australia); 27.955, 10.3 (A. Amorim,
Florianopolis, Brazil); 28.494, 10.3 (Benn); 28.714, 10.3 (D. Blane,
Henley-on-Klip, South Africa).
     P. Luckas, University of Western Australia, obtained low-resolution CCD
spectroscopy (resolution about 530; 600 lines/mm; range 380-720 nm; S/N about
100; total exposure 3600 s) of PNV J18205200-2822100 on Oct. 27.5 UT with a
35-cm reflector at Shenton Park Observatory, Perth.  The spectrum suggests
an optically thick stage of nova expansion.  Neither He I nor other CNO
absorption lines were present; the Na I D doublet displayed only absorption
(likely interstellar).  The Balmer series were seen in emission through
H_delta with little evidence for any P-Cyg absorption, with a low maximum
radial velocity (HWZI) of -750 +/- 50 km/s at H_alpha and H_beta.  There is,
however, a broader weak extended wing at H_alpha (at about 5 percent of the
continuum and only a few percent of the peak intensity) that extends to
nearly 1050 km/s.  Several lines showed moderately strong P-Cyg profiles,
notably Fe II [492.3-, 501.8-, and (weaker) 516.9-nm] and Si II (634.7- and
637.1 nm); no forbidden or intercombination transitions were present.  The
metallic lines were typically 10-15 percent of the continuum.


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

                         (C) Copyright 2016 CBAT
2016 October 29                  (CBET 4334)              Daniel W. E. Green