Central Bureau for Astronomical Telegrams
IAUC 5083: 1990V, 1990X; 1990Y; V632 Cyg
The following International Astronomical Union Circular may be linked-to from your own Web pages, but must not otherwise be redistributed (see these notes on the conditions under which circulars are made available on our WWW site).
Read IAUC 5084
Circular No. 5083
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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
MARSDEN or GREEN@CFA.BITNET MARSDEN or GREEN@CFAPS2.SPAN
SUPERNOVAE 1990V AND 1990X
A. V. Filippenko and J. C. Shields, University of California
at Berkeley, report: "CCD spectra (range 390-710 nm, resolution
1.2 nm) of several supernova candidates were obtained on Aug. 29
and 30 UT with the Shane 3-m reflector at Lick Observatory. We
confirm that SN 1990V (cf. IAUC 5074) is of type II, probably within
1-2 months past maximum brightness. H-alpha emission is prominent,
as are the H-alpha and H-beta absorption lines. SN 1990X (cf.
IAUC 5076) is also of type II, at a comparable phase. Although H-
alpha emission is strong and broad, the absorption component is
rather weak."
SUPERNOVA 1990Y IN ANONYMOUS GALAXY
Filippenko and Shields also report that SN 1990Y (cf. IAUC
5080) was observed as above, and found to be a type-Ia supernova,
probably somewhat over a month past maximum brightness. The nucleus
of the parent galaxy exhibits strong, narrow H-alpha emission,
characteristic of H II regions, at a redshift of about 0.04.
M. Della Valle, J. Danziger, and C. Gouiffes, European Southern
Observatory, communicate: "A CCD spectrum of SN 1990Y was obtained
on Aug. 30.2 UT with the 3.54-m New Technology Telescope (+ new
EMMI spectrograph) at La Silla. The spectrum is dominated by strong
absorptions of Si II (635.5 nm), Fe II (521.5, 492.4 nm), Na I
(589.2 nm), and Mg II (448.1 nm), indicating a type-Ia supernova,
about 15-20 days past maximum light. The redshift of the host
galaxy, determined from the absorption of Mg I (518 nm) and from
line emission of H-alpha and [S II], is z = 0.036. The expansion
velocity derived from the difference between the rest wavelength
in the galaxy's frame and the minimum of the absorptions is about
9000 km/s, normal for a type-Ia SN at this phase."
V632 CYGNI
G. M. Hurst, Basingstoke, England, reports that S. Korth, Monheim,
West Germany, has observed a rare outburst of this dwarf nova (cf.
IBVS 3405). Visual magnitude estimates communicated by Hurst and
J. A. Mattei, AAVSO: Aug. 23.938 UT, 14.7 (Korth); 29.08, 14.2 (G.
Dyck, N. Dartmouth, MA); 30.23, 13.2 (C. Scovil, Stamford, CT).
1990 August 30 (5083) Daniel W. E. Green
Read IAUC 5084
Our Web policy. Index to the CBAT/MPC/ICQ pages.
