[IAUC] IAUC 9275: V5668 Sgr = N SGR 2015 No. 2 = PNV J18365700-2855420; V5667 Sgr and V5668 Sgr [25139-2012/04-R1]

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                                                  Circular No. 9275
Central Bureau for Astronomical Telegrams
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V5668 SAGITTARII = N SGR 2015 No. 2 = PNV J18365700-2855420
     As first announced on CBET 4080, J. Seach (Chatsworth Island,
NSW, Australia) reported his discovery of an apparent nova (mag
6.0) in three images (limiting mag 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. =
-28o55'42" (equinox J2000.0); he added that six follow-up images
taken with an H_alpha filter on Mar. 15.726 showed the star as a
bright H-alpha source.  E. Guido and N. Howes reported position end
figures 56s.85, 40".0 for the variable from an image taken on Mar.
16.5 with a 0.61-m astrograph.  J. Powles, Canberra, ACT,
Australia, reported that low-resolution spectroscopy obtained on
Mar. 16.628 with a 25.4-cm reflector spectrogram show the H-beta
line and emerging Fe II emission lines, suggesting this to be a
classical nova of the "Fe II" type.  The nova peaked near visual
mag 5 in mid-March.  Further details are given on CBET 4080.  The
variable was designated PNV J18365700-2855420 when it was posted at
the Central Bureau's TOCP webpage.  E. Kazarovets and N. Samus note
that the permanent GCVS designation V5668 Sgr has been assigned to
this variable.


V5667 SAGITTARII and V5668 SAGITTARII
     R. J. Rudy, D. R. Ardila, and K. B. Crawford, The Aerospace
Corporation; M. S. L. Moody, The Aerospace Corporation and
University of California at Berkeley; T. K. Safrit, The Aerospace
Corporation and the Massachusetts Institute of Technology; and R. C.
Puetter, University of California at San Diego, report 0.38- to
2.5-micron spectroscopy of V5667 Sgr (N Sgr 2015 No. 1) and V5668
Sgr (N Sgr 2015 No. 2) using the The Aerospace Corporation's
Visible and Near-Infrared Imaging Spectrograph on the 3-m Shane
reflector at Lick Observatory.  Both novae still display numerous
optical and infrared Fe II lines along with lines from C I, N I,
O I, and Ca II.  V5667 Sgr has a rich forbidden-line spectrum
including features of [O I], [O II], [O III], [N I], and [N II]; it
also displays fairly strong emission from He II but has not yet
produced coronal lines.  Extinction values derived from the O I
lines are E(B-V) = 0.2 +/- 0.15 for V5667 Sgr and 0.5 +/- 0.2 for
V5668 Sgr.  V5668 Sgr has formed dust; its spectrum rises steeply
beyond 1.5 microns, characteristic of hot (800 K) dust emission.
The authors thank E. Kovacs (Lick Observatory) for his help in
acquiring the data and the Aerospace Technical Investment Program
for supporting these observations.  Also, research at Lick
Observatory is partially supported by a generous gift from Google.

                      (C) Copyright 2015 CBAT
2015 July 31                   (9275)            Daniel W. E. Green