Broadband Studies of BHCs in the High, Soft State
Previous work with OSSE has shown that galactic black hole candidates in
the X-ray high, soft state have power-law emission above 50 keV that
extends at least to energies comparable to the electron rest mass.
We report on recent contemporaneous observations of the transients
XTE J1550-564 and GRS 1915+105 with ASCA, RXTE, and OSSE in the
high, soft state. During the OSSE observations of both objects, the
emission above 50 keV was slowly declining, covering a range of
a factor of three in the former case and a factor of ten in the latter.
This is the first time that high sensitivity observations above 50 keV
have been made of these objects over such a wide range in intensity.
File translated from TEX by TTH, version 2.32.
On 16 Jul 1999, 09:19.