[IAUC] CBET 4080: 20150320 : NOVA SAGITTARII 2015 No. 2 = PNV J18365700-2855420

Vie Mar 20 04:29:49 ART 2015

                                                  Electronic Telegram No. 4080
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 2015 No. 2 = PNV J18365700-2855420
     John Seach, Chatsworth Island, NSW, Australia, reports his discovery of
an apparent nova (mag 6.0) in three images (limiting magnitude 11.0) taken on
Mar. 15.634 UT with a digital SLR camera (+ 50-mm-f.l. f/1.0 lens); he gave
the position of the new object as R.A. = 18h36m57s.0, Decl. = -28d55'42"
(equinox J2000.0).  Seach adds that follow-up six images taken with an
H-alpha filter on Mar. 15.726 show the star as a bright H-alpha source.  The
variable was designated PNV J18365700-2855420 when it was posted at the
Central Bureau's TOCP webpage.
     Additional CCD magnitudes for PNV J18365700-2855420:  Mar. 14.590 UT,
[10.5 (Seach); 15.802, 5.3 (K. Itagaki, Teppo-cho, Yamagata, Japan; 0.5-m
f/6.8 reflector; position end figures 56s.87, 39".3); 16.5, 5.8 (E. Guido
and N. Howes; remotely with an ITelescope 0.61-m f/6.5 astrograph at Auberry,
CA, USA; position end figures 56s.85, 40".0; UCAC-4 catalogue reference
stars; an animated comparison between their image and a 1996 red Digitized
Sky Survey image is posted at URL http://bit.ly/1EpSCS9; their annotated
confirmation image is posted at URL http://bit.ly/1FrQLhi); 16.795, V = 5.86
+/- 0.17 (S. O'Connor, St. George, Bermuda; via E. O. Waagen, AAVSO); 17.378,
V = 6.3 +/- 0.1 (I. Bryukhanov, Minsk, Belarus; via Waagen); 18.168, V =
5.45 +/- 0.17 (W. Vollmann, Vienna, Austria; via Waagen).  Visual magnitude
estimates:  Mar. 16.749, 6.0 (A. Pearce, Nedlands, Western Australia);
18.190, 5.4 (P. Schmeer, Bischmisheim, Germany); 18.766, 5.5 (Pearce);
     Schmeer reports that Itagaki's position for PNV J18365700-2855420 is
very close to a star of magnitude 15 with position end figures 56s.853,
39".51 in the GSC 2.3 catalogue; 56s.912, 38".88 in the USNO-B1.0 and NOMAD1
catalogues; and 56s.839, 39".80 in the 2MASS catalogue (J = 15.2, H = 15.2,
K = 14.9).
     J. Powles, Canberra, ACT, Australia, reports on spectroscopy obtained
on Mar. 16 with a 25.4-cm f/10 Schmidt-Cassegrain reflector (+ L200 Littrow
Spectrograph + Atik 383L CCD camera).  A low-resolution spectrogram (R = 300)
was obtained on Mar. 16.628 UT (twelve 180-s exposures), and a medium-
resolution spectrogram (R = 8000) was obtained on Mar. 16.671 (eleven 600-s
exposures).  Spectral lines indicate a classical nova of the "Fe II" type.
The medium-resolution spectrum centered on 500 nm shows the H-beta line and
emerging Fe II emission lines at 492.4-, 501.8-, and 515.9 nm.  The P-Cyg
profiles in this spectrum revealed an ejecta expansion velocity of about
2400 km/s (measured from the blue wing of the absorption component to the
peak of the emission component).


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                         (C) Copyright 2015 CBAT
2015 March 20                    (CBET 4080)              Daniel W. E. Green