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IAUC 4527: 1988a; 1987A; 1987p

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                                                  Circular No. 4527
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

     William Liller, Vina del Mar, Chile, reports his discovery of
a comet.  The following observations are available:

    1988 UT           R.A. (1950) Decl.        m1     Observer
    Jan. 11.0646     23 50.9      -28 18      13      Liller
         12.444      23 50.9      -27 20              Cragg
         12.477      23 50.9      -27 19      10.2    McNaught

W. Liller (Vina del Mar, Chile).  0.2-m Schmidt.  Two 2-min
   exposures 30 min apart, 2415 film, taken in course of PROBLICOM
   survey.  Object diffuse, coma diameter 1', faint condensation.
T. Cragg and R. H. McNaught (Coonabarabran, N.S.W.).  0.32-m
   reflector. Magnitude estimate on Jan. 12.457 UT (20 x 120
   binoculars); coma diameter 6'.  Cragg notes nearly stellar nucleus.

     W. R. Cook, D. Palmer, T. Prince, S. Schindler, C. Starr and
E. Stone, California Institute of Technology, report: "Hard x-ray
and gamma-ray observations of SN 1987A were made during the period
1987 Nov. 18.6-18.9 UT with the Caltech imaging gamma-ray spectrometer
launched by balloon from Alice Springs.  Using 2.5 hr of data, we
detected the supernova at 4.9-sigma significance in the energy range
40-1300 keV.  The spectrum appears to be significantly harder than
that of the Crab gamma-ray source, having a photon spectral index of
-0.9 if a power-law.  The flux values detected below 300 keV are
consistent with those measured earlier by the HEXE instrument on
the Mir spacecraft (1987, Nature 330, 227).  Flux was detected at
the 2.6- sigma level from the sum of counts in two energy ranges: 81-
keV wide centered on 847 keV and 93-keV wide centered on 1238 keV.
A preliminary estimate for the flux in each of these two energy
ranges yields (1.1 +/- 0.6) x 10**-3 photons cm-2 s-1."

     Total visual magnitude estimates: 1987 Dec. 24.20 UT, 7.1 (C.
Spratt, Victoria, BC, 11 x 80 binoculars; 15' tail in p.a. 45 deg);
28.19, 7.3 (A. Hale, Las Cruces, NM, 0.41-m reflector); 1988 Jan.
1.41, 8.0 (Y. Sugiyama, Hiratsuka, Japan, 0.16-m reflector); 3.16,
7.6 (Hale); 6.45, 8.5 (Sugiyama); 8.45, 8.3 (Sugiyama).

1988 January 12                (4527)              Brian G. Marsden

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