Central Bureau for Astronomical Telegrams

Central Bureau for Astronomical Telegrams -- Image credits

IAUC 4590: 1988L; 1987A; 1986l

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 4589  SEARCH Read IAUC 4591
IAUC number

                                                  Circular No. 4590
Central Bureau for Astronomical Telegrams
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

     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.

     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.

     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

Read IAUC 4589  SEARCH Read IAUC 4591

Our Web policy. Index to the CBAT/MPC/ICQ pages.

Valid HTML 4.01!