Central Bureau for Astronomical Telegrams
IAUC 4350: 1987A; 4U 0115+63
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Circular No. 4350
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
TWX 710-320-6842 ASTROGRAM CAM Telephone 617-495-7244/7440/7444
SUPERNOVA 1987A IN THE LARGE MAGELLANIC CLOUD
S. Cristiani and C. Gouiffes, European Southern Observatory;
R. Hanuschik, Bochum University; and P. Magain, ESO, report: "Spectra
taken at intermediate resolution (0.2-0.3 nm) between Mar. 14
and 22, with the spectrum scanner attached to the Bochum University
0.61-m telescope and with the ESO 1.5-m telescope at La Silla,
showed changes in the P-Cyg profile of H-alpha. On Mar. 15, a weak bump
at 647 nm appeared on the previously-very-smooth P-Cyg profile
(near the bottom of the absorption) which developed in the following
days, assuming a peaked structure and reaching the continuum
level about Mar. 20. A comparison with previous spectra suggests
that this is an additional emission feature. Spectra taken with
the CAT 1.4-m telescope (resolution 80000) do not show smaller-
scale structures. The precise wavelength of the relative maximum
in the spectrum is 647.0 nm, followed by a minimum at 648.8 nm.
The FWHM of the two features is 1.45 and 2.10 nm, respectively. If
identified with H-alpha, the emission corresponds to a velocity of -4500
km/s. No corresponding structures have been observed in the P-Cyg
profiles of H-beta and Ca 860-nm. Those observations suggest a
distortion in the spherical symmetric outflow of the explosion, which can
be confirmed by polarization observations of the H-alpha profile."
Provisional photoelectric photometry by J. Dawe and R. H.
McNaught with the Australian National University 0.61-m reflector
at Siding Spring Observatory: Mar. 20.456 UT, V = 4.12, B-V =
+1.58, U-B = +2.04. Further visual magnitude estimates: Mar.
19.39, 4.1 (McNaught); 19.52, 4.0 (T. Beresford, Adelaide, South
Australia); 20.45, 4.0 (McNaught); 20.48, 3.9 (Beresford).
4U 0115+63
H. Mendelson and T. Mazeh, Wise Observatory, report: "The
optical counterpart of the x-ray pulsar 4U 0115+63 is probably going
into another outburst. Between 1986 Oct. and 1987 Feb. 25, the
star was continuously brightening in I from mag 12.8 to 12.3 (+/-
0.1). Prior to the present increase of brightness, a small
decrease of 0.3 mag was observed between 1985 Aug. (I = 12.8) and
1986 Jan. (I = 13.1). Similar variations have been observed in the
V and R bands. The variations in the V band are somewhat smaller.
The 1981 x-ray outburst appeared after a similar optical behavior
(Kriss et al. 1983, Ap.J. 266, 806). Therefore, optical, x-ray
and gamma-ray observations of the system are strongly recommended."
1987 March 23 (4350) Daniel W. E. Green
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