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IAUC 4485: 1987A; 4U 0115+63; V818 Sco; OS And

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IAUC number 

                                                  Circular No. 4485
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
     R. M. Catchpole, South African Astronomical Observatory,
reports: "Results obtained at SAAO between days 147 and 257 after
core collapse indicate that, for A(V) = 0.6 mag, the e-folding
decay time for the bolometric magnitude lies between 106 and 115
days, depending on the method of flux integration.  These values
are close to the 111-day mean life of 56Co and suggest that at
present radioactive decay is the main source of energy.  We see no
evidence for any change of slope within the last few days."
     Visual magnitude estimates:  Nov. 6.41 UT, 5.9 (D. Seargent,
The Entrance, N.S.W.); 6.50, 5.8 (A. C. Beresford, Adelaide, South
Australia); 8.46, 6.0 (Beresford); 10.44, 5.9 (Beresford).


4U 0115+63
     H. Mendelson and T. Mazeh, Wise Observatory, communicate:  "The
brightness of this x-ray pulsar's optical counterpart has been
decreasing since its last eruption (IAUC 4342, 4350), from I = 12.2 +/-
0.1 in 1987 May to I = 13.3 +/- 0.1 at the end of Oct.  Similar
variations have been observed in the R and V bands.  The current
magnitude seems to be fainter than before outburst; spectroscopic and x-
ray observations are therefore urged."


V818 SCORPII
     D. A. Leahy, Physics Department, University of Calgary,
communicates: "During 1984 Dec. 18.17-18.20 UT, observations were
made which, through use of a Fast Fourier Transform algorithm,
indicate 2.93-ms pulsations in V818 Sco (= Sco X-1).  The data were
obtained with a Phoswich-type x-ray telescope built and flown by a
collaboration between the Tata Institute for Fundamental Research,
Bombay (investigators S. V. Damle, P. K. Kunte, S. Naranan, and B.
V. Sreekantan), and the University of Calgary, (investigators D. A.
Leahy and D. Venkatesan).  The detector had 0.04-ms time resolution
and covered the energy range 20-120 keV."


OS ANDROMEDAE
     Visual magnitude estimates: Sept. 30.85 UT, 13.2 (M. Verdenet,
Bourbon-Lancy, France); Oct. 17.87, 13.4 (S. Korth, Monheim, West
Germany); 28.60, 14.5: (S. Sakuma, Kawasaki, Japan).


1987 November 10               (4485)            Daniel W. E. Green

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