Central Bureau for Astronomical Telegrams
IAUC 4590: 1988L; 1987A; 1986l
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Circular No. 4590
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
MARSDEN or GREEN@CFA.BITNET MARSDEN or GREEN@CFAPS2.SPAN
SUPERNOVA 1988L IN NGC 5480
S. Perlmutter and C. Pennypacker communicate: "The Berkeley
Automated Supernova Search reports the discovery of a supernova in
NGC 5480 (R.A. = 14h04m.51, Decl. = +50D57'.7, equinox 1950.0) in
three images obtained during Apr. 30.37-30.41 UT and confirmed
during May 3.39-3.44 UT. The object, of mag 16.5, is 2".5 east
and 13" north of the galaxy's nucleus. The supernova did not
appear (95-percent confidence level) on a reference image taken in
May 1987 to limiting mag 18.5."
J. R. Graham and B. T. Soifer, California Institute of
Technology, report infrared magnitudes J = 15.15, H = 14.90, K =
14.85 (uncertainty 5 percent), obtained on May 4.1 UT with the 5-m
Hale reflector at Palomar, suggesting that the object is a
supernova of type Ia, about 10 days past maximum. They refine the
offset from the nucleus to 3".3 east, 14".3 north.
SUPERNOVA 1987A IN THE LARGE MAGELLANIC CLOUD
P. Ubertini, A. Bazzano and C. la Padula, Istituto di Astrofisica
Spaziale, CNR, Frascati; R. Sood and L. Waldron, ADFA, Department of
Physics, Canberra University; G. Frye and R. Koga, Case Western
Reserve University, Cleveland; G. Rochester and T. J. Sumner, Physics
Department, Imperial College, London; and R. Staubert and E.
Kendziorra, Astronomisches Institut, Tubingen University; communicate:
"We report that a hard x-ray observation of SN 1987A was made during
Apr. 5.00-5.42 UT with a combined hard-x-ray/high-energy gamma-ray
experiment launched by balloon from Alice Springs. A preliminary
analysis of seven hours of data from a region of 4 deg centered on the
supernova yields a 4.8-sigma detection of flux in the energy range
30-110 keV. The integral continuum flux is provisionally estimated to
be 1.4 (+/- 0.4) x 10**-4 photons cm**-2 s**-1 keV**-1 at 50 keV for a
Crab-like spectrum. This is consistent with some increase in
intensity since the first measurements in the same energy range in
August 1987 by instruments on board the MIR station."
Visual magnitude estimates by A. C. Beresford, Adelaide, South
Australia: Apr. 23.43 UT, 7.4; 25.46, 7.5; 26.50, 7.5; 27.44, 7.5;
28.39, 7.5; 29.41, 7.4; 30.41, 7.5; May 1.45, 7.5; 2.45, 7.5; 5.38, 7.5.
COMET WILSON (1986l)
Total visual magnitude estimates by A. Hale, Las Cruces, NM
(0.41-m reflector): Mar. 7.21 UT, 13.2:; 10.18, 13.5.
1988 May 5 (4590) Brian G. Marsden
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