MG11 
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Long Term Monitoring of the Hard X-ray/Gamma-Ray Emission from BATSE Black Hole Sources

The CGRO/BATSE instrument viewed numerous sources including GRS 1915+105, GRO J1655-40, GRO J0422+32, GRO J1719-24, and Cygnus X-1 almost continuously from 1991 to 2000 in the energy range 23-1800 keV. Based on analysis of the data taking into account source confusion and additional sources not included in the initial analyses, we present results from the full nine-year earth-occultation database using the JPL Enhanced BATSE Occultation data analysis Package (EBOP). Light curves with 1-day resolution are presented. Time-variable positive fluxes are observed for several sources, including in some cases a hardening of the spectrum during some epochs above ~200 keV. The time evolution of the spectra is presented, and the implications of this hard component for models of the emission from black hole binaries are discussed.