Session AB - Astronomy and Space Physics.
MIXED session, Friday morning, October 05
SWR L1, Sid W. Richardson Building
The detection of event horizons has recently been claimed, based upon a comparison of the quiescent x-ray luminosities of neutron stars (NS) and galactic black hole candidates (GBHC) in low mass x-ray binaries. The lower quiescent luminosities of GBHC were attributed to an advective accretion flow (ADAF) through an event horizon. Since there are difficulties with the ADAF model and the similar quiescent emissions of NS appear to be at least partially magnetospheric in origin, the possibility that GBHC may possess magnetic fields needs to be considered. The existing observational data appear to be consistent with magnetospheric models. This possibility needs to be rejected before accepting a model dependent detection of event horizons.