scispace - formally typeset
Search or ask a question

Showing papers in "Monthly Notices of the Royal Astronomical Society in 1980"

















Journal ArticleDOI
TL;DR: In this paper, the equations of stellar hydrodynamics are used to derive the radial variation of velocity dispersion in galaxies whose mass-to-light ratios are constant and whose brightness profiles obey the r to the 1/4 law.
Abstract: The equations of stellar hydrodynamics are used to derive the radial variation of velocity dispersion in galaxies whose mass-to-light ratios are constant and whose brightness profiles obey the r to the 1/4 law. It is found that the projected central velocity dispersion in such a system should be about 40 percent lower than the peak velocity dispersion. The observability and physical interpretation of this phenomenon is discussed. There is some evidence that a similar effect has been observed in the structure of rich clusters of galaxies.

Journal ArticleDOI
TL;DR: In this article, the authors generalize previous discussions of the steady-flow models by allowing for the effects of angular momentum, which may be important in the central cooled regions of rich clusters of galaxies.
Abstract: The paper generalizes previous discussions of the steady-flow models by allowing for the effects of angular momentum, which may be important in the central cooled regions of rich clusters of galaxies. The thermal stability of the flow is studied in a general way by relaxing the assumption that the perturbations comove. It is found that they are only unstable for a restricted range of initial parameters. Situations in which cold filaments can form are considered, and the subsequent evolution and excitation of such filaments are discussed. An estimate of the mass-to-light ratio of NGC 1275 is obtained by comparing the obtained results with the low-velocity filamentation system surrounding NGC 1275 in the Perseus cluster. Finally, the various aspects of cooling accretion flows in clusters are summarized.