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IAUC 5077: 1990W; 1990R, 1990U; 1990X

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                                                  Circular No. 5077
Central Bureau for Astronomical Telegrams
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Telephone 617-495-7244/7440/7444 (for emergency use only)
TWX 710-320-6842 ASTROGRAM CAM     EASYLINK 62794505

     R. H. McNaught, University of Adelaide, reports the following
precise position measured from an Uppsala Southern Schmidt film
taken Aug. 18.39 UT:  R.A. = 16h48m26s.58, Decl. = -59 07'56".2
(equinox 1950.0).  The supernova is located 7".4 east and 5".4 north
of the galaxy's center.  Another star (mag 16) is located 11".9 east
and 12".9 north of the galaxy's nucleus.

     R. Lopez, University of Barcelona; J. A. Rodriguez and M.
Balcells, Observatorio de Roque de los Muchachos; and J. Cepa,
Instituto de Astrofisica Canarias, report:  "We obtained low-resolution
spectra (range 330-1050 nm) of supernovae 1990R and 1990U on Aug. 15
UT with the faint object spectrograph (FOS) on the ORM 2.5-m Isaac
Newton Telescope at La Palma.  Spectra of the type-Ia supernova
1990R in UGC 11699 show absorption features of the Fe II blends
(492.4, 521.5, 553.5, 620.0, 647.9 nm), Na I (589.2 nm), O I (777.3
nm) and O I + Mg II (822.7, 823.2 nm).  Expansion velocities
inferred from these absorptions, corrected for the redshift of the
host galaxy, are in the range 7100-9800 km/s for Fe II, 10 900 km/s
for Na I, 9200 km/s for O I, and about 9000 km/s for the O I + Mg
II blend.  This supernova may be within two months of maximum brightness
(cf. IAUC 5054).  The spectra were taken at R.A. = 21h09m57s.1,
Decl. = +12 24'15" (equinox 1950.0).
     The spectrum of SN 1990U in NGC 7479 shows absorption features
attributed to He I (587.6 nm) blended with strong Na D, He I (706.5
nm), O I (777.3 nm), and the Ca II infrared triplet (857.9 nm),
probably blended with the O I/S I (888.4, 888.0 nm) doublet.  The
spectrum appears contaminated by prominent (but narrow) H-alpha and
H-beta emission features at about the redshift of the parent galaxy.
Expansion velocities of the ejecta are from about 8500 km/s for O I
(777.3 nm) to about 10 500 km/s for Ca II.  The spectrum was taken
at R.A. = 23h02m24s.7, Decl. = +12 02'08" (equinox 1950.0)."

     Corrigendum.  C. Pollas reports that the accurate position
reported on IAUC 5076 was of the nucleus of the galaxy, not
the supernova.

1990 August 20                 (5077)             Daniel W. E. Green

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