Astronomy and Astrophysics – Astrophysics
Scientific paper
Jul 1982
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1982a%26a...111...16d&link_type=abstract
Astronomy and Astrophysics, Vol.111, P. 16, 1982
Astronomy and Astrophysics
Astrophysics
15
Scientific paper
Deviations from the classical (evaporational) evolution of large stellar systems appearing when one takes into account the dissipative effects due to formation and hardening of binaries, including hardening of relics (i. e. primordial binaries) are considered. Both the rate of energy dissipation from a stellar system caused mainly by tidal interactions of single stars and by formation of binaries, and the rate of a system's heating in the process of hardening of hard binaries formed were calculated in detail in Paper I (Ozemoy and Dokuchaev, 1982). Stellar system's evolution equations taking into account evaporation of stars together with dissipation and heating effects are solved in different limiting cases, when heating of the system by binaries dominates over its cooling, or vice versa. The results are applied to consider evolution of globular clusters and galactic nuclei at stages when star collisions do not yet have a substantial effect on the evolution.
For globular clusters the influence of heating by binaries being negligibly small for the majority of the observed clusters, becomes rather essential in the course of their subsequent evolution. A cluster comes to such an evolution regime that its velocity dispersion in the course of contraction reaches the value of about 30 km s-1 and then remains almost constant.
For galactic nuclei the influence of binaries upon evolution depends essentially on the initial velocity dispersion of stars. In the nuclei where its value is comparatively high (υ ≳ 150 km s-1 at the star density n = 107 pc-3), the dissipative effects due to tidal interaction of stars are dominating. These effects lead to an accelerated contraction of the nucleus in which by the beginning of the collisional stage of evolution a considerable part of the initial amount of stars remains. In nuclei with comparatively small υ, the effects of heating by binaries can play a rather important role. In such systems υ increases at first and then, having reached a maximum, decreases and finally comes to a constant value, the same as in the evolution of globular clusters. However, along with binary formation, an important role in the evolution of such galactic nuclei may be played by the effects of stellar collisions which require further investigation.
Dokuchaev Viacheslav I.
Ozernoy Leonid M.
No associations
LandOfFree
Dissipative Evolution of Collisionless Stellar Systems - Part Two - Influence of Binaries on the Evolution of Globular Clusters and Galactic Nuclei does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Dissipative Evolution of Collisionless Stellar Systems - Part Two - Influence of Binaries on the Evolution of Globular Clusters and Galactic Nuclei, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dissipative Evolution of Collisionless Stellar Systems - Part Two - Influence of Binaries on the Evolution of Globular Clusters and Galactic Nuclei will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1021939