Tracing the Dynamical History of the Globular Cluster 47 Tucanae

Details Tracing the Dynamical History of the Globular Cluster 47 Tucanae Tracing the Dynamical History of the Globular Cluster 47 Tucanae

2006-07-04

arxiv.org/abs/astro-ph/0607053v1

Astrophys.J.650:195-202,2006

Astronomy and Astrophysics

Astrophysics

Accepted by ApJ

Scientific paper

10.1086/507323

We use two stellar populations in the globular cluster 47 Tucanae to trace its dynamical history: blue stragglers and low mass main sequence stars. We assumed that the blue stragglers were formed through stellar collisions in all regions of the cluster. We find that in the core of the cluster, models of collisional blue stragglers agree well with the observations as long as blue stragglers are still continuing to form and the mass function in the cluster is extremely biased towards massive stars (x=-8 where a Salpeter mass function has x=+1.35). We show that such an extreme mass function is supported by direct measurements of the luminosity function of main sequence stars in the centre of the cluster. In the middle region of our dataset (25'' to 130'' from the cluster centre), blue straggler formation seems to have stopped about half a Gyr ago. In the outskirts of the cluster, our models are least successful at reproducing the blue straggler data. Taken at face value, they indicate that blue straggler formation has been insignificant over the past billion years, and that a Salpeter mass function applies. However, it is more likely that the dominant formation mechanism in this part of the cluster is not the collisional one, and that our models are not appropriate for this region of the cluster. We conclude that blue stragglers can be used as tracers of dynamics in globular clusters, despite our incomplete understanding of how and where they were formed.

Affiliated with

Also associated with

No associations

Rating

Tracing the Dynamical History of the Globular Cluster 47 Tucanae 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 Tracing the Dynamical History of the Globular Cluster 47 Tucanae, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Tracing the Dynamical History of the Globular Cluster 47 Tucanae will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-240293