A Measurement of Diffusion in 47 Tucanae

Abstract

Using images from the Hubble Space Telescope Wide-Field Camera 3, we measure the rate of diffusion of stars through the core of the globular cluster 47 Tucanae using a sample of young white dwarfs identified in these observations. This is the first direct measurement of diffusion due to gravitational relaxation. We find that the diffusion rate $\kappa \approx 10-13$ arcsecond${}^2$ Myr${}^{-1}$ is consistent with theoretical estimates of the relaxation time in the core of 47 Tucanae of about 70 Myr.

12 pages, 10 figures, accept for publication in the Astrophysical Journal (added a short passage on blue stragglers descendants and corrected a minor typographical error in Eq. 15)

References in corpus (4)

• Modules for Experiments in Stellar Astrophysics (MESA)
• HST Proper Motions and Stellar Dynamics in the Core of the Globular Cluster 47 Tucanae
• Stellar Exotica in 47 Tucanae
• Comparative study between N-body and Fokker-Planck simulations for rotating star clusters - II. 2-component models

Cited by in corpus (5)

• Deep HST Imaging in 47 Tucanae: A Global Dynamical Model
• Searching in the dark: the dark mass content of the Milky Way globular clusters NGC288 and NGC6218
• Formation and Evolution of Blue Stragglers in 47 Tucanae
• The contribution of dissolving star clusters to the population of ultra-faint objects in the outer halo of the Milky Way
• The Next Generation Virgo Cluster Survey. XXVIII. Characterization of the Galactic White Dwarf Population