Electronic Telegram No. 5297
Central Bureau for Astronomical Telegrams
Mailing address:  Hoffman Lab 209; Harvard University;
 20 Oxford St.; Cambridge, MA  02138; U.S.A.
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Prepared using the Tamkin Foundation Computer Network


V1718 SCORPII = TCP J17183380-3123452 = NOVA SCORPII 2023 No. 3
     C. Jacques, Belo Horizonte, Brazil, reports that an apparent nova (mag
12.6) was discovered by the Brazilian Transient Search team (E. Pimentel, C.
Barreto, C. Colesanti, C. Jacques, J. Amancio, J. Ribeiro, L. Amaral, M.
Domingues, P. Holvorcem, and T. Napoleao) on three unfiltered 10-s CCD frames
(limiting mag 16.5) taken on Sept. 1.982 UT with a 280-mm f/2.2 astrograph at
the SONEAR 2 Observatory, the position of the variable star given as R.A. =
17h18m33s.80, Decl. = -31d23'45".2 (equinox J2000.0).  The designation TCP
J17183380-3123452 was assigned to this star when Jacques posted it to the
Central Bureau's TOCP webpage.  Nothing is visible at this position on the
previous frames taken of this field by Jacques' group (limiting mag 16.5)
on 2023 June 12.170.
     R. Kaufman (Bright, Victoria, Australia) measured magnitude 13.4 (TG band,
approximating V) for TCP J17183380-3123452 on Sept. 2.56 UT in digital SLR
camera images (200-mm-f.l. lens) obtained in bright moonlight; his image is
posted at website URL https://photos.app.goo.gl/uKjPyPvPDUBSLQbX9.  Kaufman
notes the redness of the variable.
     A. Pearce (Nedlands, W. Australia) reports position end figures 33s.81,
45".9 (reference star positions from the Gaia DR2 catalogue) for TCP
J17183380-3123452 from CCD images obtained on Sept. 3.363 UT with a 0.50-m
R-COP reflector at Siding Spring Observatory, NSW, adding that the variable
appears close to an uncatalogued star in a DECaPS image.  Pearce's photometry
for the variable:  Sept. 3.362, B = 15.21; 3.363, V = 13.41; 3.364, R = 11.99;
3.365, I = 10.62.
     CCD photometry for TCP J17183380-3123452 from images taken by S. Kiyota
(Kamagaya, Japan) on Sept. 3.376 UT using an iTelescope 0.50-m f/6.8 reflector
at Siding Spring:  B = 15.79, V = 13.11, R_c = 11.75, I_c = 10.46.  His image
is posted at website URL https://meineko.com/ccd/TCP_J17183380-3123452.jpg.

     Spectroscopy (range 400-800 nm) by J. Strader et al. obtained on Sept.
16.99 UT with the 4.1-m SOAR telescope shows a red continuum with strong,
broad emissions lines including H-alpha (FWHM about 2220 km/s) and O I, with
numerous Fe II lines, consistent with the spectrum of a moderately reddened
classical nova (cf. URL https://www.astronomerstelegram.org/?read=16246).

     E. Kazarovets (Institute of Astronomy, Moscow) informs the Bureau that
the permanent GCVS designation V1718 Sco has been assigned to this nova.


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

                         (C) Copyright 2023 CBAT
2023 October 2                   (CBET 5297)              Daniel W. E. Green