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IAUC 6847: 1998X; N Sgr 1998; 1998S

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                                                 Circular No. 6847
Central Bureau for Astronomical Telegrams
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions)
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     Simon Woodings, Ralph Martin, and Andrew Williams report their
discovery of an apparent supernova (R = 17) on a CCD frame taken
on Mar. 13.88 UT (confirmed on Mar. 15.86) as part of the Perth
Astronomy Research Group's automated supernova search with the
0.61-m Perth-Lowell telescope.  SN 1998X is located 23".8 +/- 1"
west and 3".1 +/- 1" south of the center of NGC 6754 (R.A. =
19h11m.4, Decl. = -50o39', equinox 2000.0).
     F. Patat, European Southern Observatory, (ESO); and M. Della
Valle, Padova University, write:  "We have observed SN 1998X with
the ESO 1.5-m telescope (+ Boller & Chivens spectrograph; exposure
time 45 min; range 320-710 nm, resolution 0.5 nm) on Mar. 23.40 UT
at La Silla.  A preliminary reduction of the CCD spectrogram shows
that this object is a type-II supernova, about 3-4 months after
explosion.  The spectrum consists of a multitude of lines with the
usual P-Cyg profiles, superimposed on a red continuum.  Most of the
lines arise from the H I Balmer series and Na I, Sc II, and Fe II.
The expansion velocities deduced from the minima of the most
prominent features are 6100 (H-alpha), 3050 (Na I), and 3570 km/s
(Fe II).  The recession velocity at the supernova location is 3110
km/s, as deduced from the narrow H-alpha emissions.  A narrow
interstellar absorption of Na I D, arising in the parent galaxy, is
clearly visible at 595.3 nm."

     S. Nakano, Sumoto, Japan, forwards the following position and
magnitude for this object (cf. IAUC 6846) from Y. Kushida,
Yatsugatake South Base Observatory (0.40-m f/6 reflector), from an
image obtained on Mar. 23.771 UT:  R.A. = 18h21m40s.47, Decl. =
-27o31'38".0 (equinox 2000.0), V = 8.1.  Nakano also reports the
following position end figures from M. Aoki, Toyama (0.43-m f/6
reflector), who reported V = 7.8 on Mar. 23.724:  40s.47, 37".9.
The closest star present in the USNO A1.0 catalogue (and on the
Digital Sky Survey) is one of mag about 17 located 6".5 north of
the nova.
     G. J. Garradd, Loomberah, N.S.W., reports the following
position end figures and magnitude from an unfiltered CCD image
obtained on Mar. 23.682 UT with a 0.25-m f/4.1 reflector:  40s.51,
38".5, 8.2.

     Revised position end figures and magnitude from J.-C. Merlin,
regarding line 11 of IAUC 6831:  06s.11, 55".8, 12.5.

                      (C) Copyright 1998 CBAT
1998 March 23                  (6847)            Daniel W. E. Green

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