Binaries and the dynamical mass of star clusters

Details Binaries and the dynamical mass of star clusters Binaries and the dynamical mass of star clusters

2007-10-05

arxiv.org/abs/0710.1207v1

Astronomy and Astrophysics

Astrophysics

Comments: 2 pages. Conference proceedings for IAUS246 'Dynamical Evolution of Dense Stellar Systems', ed. E. Vesperini (Chief

Scientific paper

10.1017/S1743921308015755

The total mass of a distant star cluster is often derived from the virial theorem, using line-of-sight velocity dispersion measurements and half-light radii, under the implicit assumption that all stars are single (although it is known that most stars form part of binary systems). The components of binary stars exhibit orbital motion, which increases the measured velocity dispersion, resulting in a dynamical mass overestimation. In this article we quantify the effect of neglecting the binary population on the derivation of the dynamical mass of a star cluster. We find that the presence of binaries plays an important role for clusters with total mass M < 10^5 Msun; the dynamical mass can be significantly overestimated (by a factor of two or more). For the more massive clusters, with Mcl > 10^5 Msun, binaries do not affect the dynamical mass estimation significantly, provided that the cluster is significantly compact (half-mass radius < 5 pc).

Affiliated with

Also associated with

No associations

Rating

Binaries and the dynamical mass of star clusters 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 Binaries and the dynamical mass of star clusters, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Binaries and the dynamical mass of star clusters will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-329055