Central Bureau for Astronomical Telegrams
IAUC 7091: 1999E; 1998fc, 1998fd
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Circular No. 7091
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
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SUPERNOVA 1999E IN ANONYMOUS GALAXY
E. Cappellaro and M. Turatto, Padova Observatory; and P.
Mazzali, Trieste Observatory, write: "Based on the spectrum taken
by Jha et al., given at
http://cfa-www.harvard.edu/cfa/oir/Research/supernova/spectra/sn99e.99Jan19.gif,
and on the description on IAUC 7090 of the Filippenko spectrum, SN
1999E is very similar to SN 1997cy (Turatto et al., in
preparation). Although the evolution is very slow, the best match
is with the spectrum taken about 4 months after discovery
(http://athena.pd.astro.it/~supern/news/sn97cy_251198.gif), with
emission lines of H, Ca II, and [Fe II] resulting from the
interaction of the ejecta with a dense circumstellar material, as
in SN 1988Z (Turatto et al. 1993, MNRAS 262, 128). SN 1997cy has
been associated with GRB 970514 (Woosley et al., Ap.J., submitted,
and http://xxx.lanl.gov/abs/astro-ph/?9806299), it reached M_v > =
-20.06 (H_0 = 65 km sE-1 MpcE-1), and it was to our knowledge the
intrinsically brightest supernova ever discovered. Based on the
analogy with 1997cy, we expect that the spectral evolution and the
luminosity decline of 1999E will both be very slow."
A. V. Filippenko, D. C. Leonard, and A. G. Riess, University
of California at Berkeley, report: "Another spectrum (range 380-630
nm) of the luminous, peculiar type-IIn supernova 1999E (cf. IAUC
7089, 7090) was obtained on Jan. 20 UT with the Keck-II telescope.
The features are similar to those reported by Jha et al. Combining
both of our own spectra, perhaps the closest match is to that of SN
1997cy (whose spectrum was obtained by B. P. Schmidt), which was
likewise extremely luminous. In some respects (e.g., breadth), the
undulations also resemble those of the luminous SN 1998bw, which
may have been associated with GRB 980425."
SUPERNOVAE 1998fc AND 1998fd IN ANONYMOUS GALAXIES
Filippenko et al. also report that a spectrum (range 510-880
nm) obtained on Jan. 20 UT with the Keck-II telescope reveals that
SN 1998fc (cf. IAUC 7082) is of type Ia at redshift 0.10, perhaps a
month past maximum brightness. The emission-line intensity ratios
are somewhat peculiar; specifically, the feature at rest wavelength
550 nm is unusually strong. A similar spectrum obtained on Jan. 19
reveals that SN 1998fd (cf. IAUC 7082) is of type Ia, a few weeks
past maximum brightness; a redshift of 0.24 was measured from
absorption lines in the host galaxy.
(C) Copyright 1999 CBAT
1999 January 21 (7091) Daniel W. E. Green
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