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A comprehensive survey of the morphology of the hot interstellar medium (ISM) in normal elliptical galaxies shows that these systems are, at best, only approximately in hydrostatic equilibrium, and that the degree of morphological disturbance is tightly correlated with the radiative luminosity of the central active galactic nucleus (AGN). In this contribution we show that the temperature profiles in these systems can be outwardly rising, outwardly falling, both, or neither; and that the sign of the temperature gradient in the main bodies of the galaxies is strongly correlated with AGN power. This strengthens the view that AGN are responsible for stirring up the hot ISM in nearly all ellipticals, and further suggests that the role and/or mode of AGN feedback qualitatively differs in systems with weak and strong AGN. [ABSTRACT FROM AUTHOR]

We present the results of a systematic morphological analysis of the X-ray emission of the hot interstellar medium (ISM) in 54 normal elliptical galaxies observed with the Chandra satellite. We find evidence for the gas not to be resting completely in hydrostatic equilibrium. In particular, we find that optical and X-ray ellipticities are uncorrelated, contrary to expectations from hydrostatic equilibrium. We also demonstrate that the degree of asymmetry in the gas correlates positively with both the 20 cm radio luminosity and the X-ray luminosity of the central point source, emphasizing the general importance of AGN feedback even in normal elliptical galaxies. [ABSTRACT FROM AUTHOR]

Fokker-Planck simulations of the evolution of globular clusters containing binaries produced by two-body tidal captures and three-body interactions have been separately carried out. In both cases, the expansion phase following the first core collapse is found to be unstable when the codes are run with small time steps (of order the central relaxation time tro). Large amplitude highly nonlinear oscillations develop in the core structure parameters such as central density. The instability observed for the case of three-body binaries is quite similar to that found by Bettwieser and Sugimoto in several studies based on the fluid dynamical model for star clusters. Goodman (1986) has shown for the case of three-body binaries that the instability is intrinsic to the model rather than numerical in origin. A large-scale study of core oscillations is planned using the Cray X-MP at the National Center for Supercomputing Applications. [ABSTRACT FROM AUTHOR]