Electronic Telegram No. 4364
Central Bureau for Astronomical Telegrams
Mailing address:  Hoffman Lab 209; Harvard University;
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Prepared using the Tamkin Foundation Computer Network


NOVA SCORPII 2017 = PNV J16521887-3754189
     S. Nakano, Sumoto, Japan, reports the discovery of an apparent nova
(mag 11.7) by H. Nishimura (Kakegawa, Shizuoka-ken, Japan) on three unfiltered
10-s frames using a Canon digital camera (+ 200-mm f/3.2 lens) on Feb. 1.862
UT.  The variable is located at R.A. = 16h52m18s.87, Decl. = -37d54'18".9
(equinox J2000.0).  The variable was designated PNV J16521887-3754189 when it
was posted at the Central Bureau's TOCP webpage.  Additional CCD magnitudes
for PNV J16521887-3754189:  Jan. 30.868, 12.5 (Nishimura); Feb. 2.857, 12.1
(Nishimura); 6.836, 12.7 (Nishimura); 10.702, B = 14.7, V = 14.1, R_c = 11.8,
I_c = 12.5 (S. Kiyota, Kamagaya, Japan; remotely with an iTelescope 0.50-m
f/4.5 CDK astrograph at Siding Spring; position end figures 18s.63, 16s.4;
image posted at URL http://meineko.sakura.ne.jp/ccd/PNV_16521887-3754189.jpg);
10.835, 12.6 (T. Noguchi, Chiba-ken, Japan, 0.23-m f/6.3 Schmidt-Cassegrain
reflector; position end figures 18s.66, 16".7; communicated by Nakano; image
posted at URL http://park8.wakwak.com/~ngc/images/PNVinSco_20170210.jpg);
23.718, R = 11.7 (S. Foglia, L. Buzzi, P. Concari, C. Cremaschini, G. Galli,
and M. Tombelli, using an iTelescope 0.15-m f/7 refractor at Siding Spring;
position end figures 18s.65, 16".3; image posted at website URL
http://www.asteroids.altervista.org/obs/PNV_J16521887-3754189.gif).  Noguchi
reports that a star of mag 15.9 is present at the position of PNV
J16521887-3754189 on a Digitized Sky Survey image from 1995.  P. Schmeer,
Bischmisheim, Germany, writes that the red star noted by Noguchi as blue
magnitude 18.5 and red magnitude 15.0-15.9 in the USNO-B1.0 catalogue, V =
17.0 in the GSC2.3 catalogue, and J = 10.3, H = 9.1, K = 8.6 in the 2MASS
catalogue.
     Optical spectroscopy (range 480-880 nm; resolution 0.56 nm) obtained on
Feb. 12.3 UT by J. Strader, L. Chomiuk, A. Bahramian, and C. Britt, Michigan
State University, with the 4.1-m SOAR telescope (+ Goodman Spectrograph)
at Cerro Pachon shows that PNV J16521887-3754189 is a nova.  The spectrum,
showed broad/nearly rectangular and double-peaked emission in H and He lines.
The half-width-at-zero-intensity of the emission is around 2000 km/s.
H-alpha is saturated in the spectrum.  The next-strongest lines are H_beta
and the He I lines at 587.5 and 706.5 nm, though some He II lines such as
541.2-nm are also strong.  No Fe II lines are observed.  The prominence of
broad He emission lines and the absence of Fe II lines indicates a
classification as an "He/N"-type nova.  O I at 844.6-nm is well-detected,
while O I at 777.3 nm is not detected, consistent with the high O I
844.6-nm/777.3-nm ratio observed for He/N novae in decline (Williams 2012,
A.J. 144, 98).


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

                         (C) Copyright 2017 CBAT
2017 February 23                 (CBET 4364)              Daniel W. E. Green