The Caltech gamma-ray imaging telescope observed the hard X-ray and ga
mma-ray emission from SN 1987A as it evolved between 1987 May and 1989
April, in a series of four balloon flights from Alice Springs, NT, Au
stralia. Observations of the Crab Nebula and Pulsar provided in-flight
data on pointing accuracy and instrument function for each flight. Re
sults presented here include our measurements on 1987 November 18 (D26
8) and 1988 April 12 (D414) of both line emission at 847 and 1238 keV
from the decay of Co-56, and Compton-scattered continuum above 50 keV.
Upper limits for both line and continuum emission were obtained on 19
87 May 20 (D86) and 1989 April 4 (D771). For the D268 and D414 continu
um measurements, our results are best-fit by a differential power law
of the form dN/dE = kappaE(-gamma)(cm-2 s-1 keV-1) for the energy rang
e 50-800 keV. Our corresponding line measurements were fit with Gaussi
an profiles, containing additional terms for the underlying continuum.
We compare our flux measurements and upper limits to those from other
experiments and to predictions of theoretical models.