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.

arXiv comment12 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 (18)

• Modules for Experiments in Stellar Astrophysics (MESA)
• Correcting for the Effects of Interstellar Extinction
• An Improved Spectroscopic Analysis of DA White Dwarfs from the Sloan Digital Sky Survey Data Release 4
• Asteroseismology of old open clusters with Kepler: direct estimate of the integrated RGB mass loss in NGC6791 and NGC6819
• Multiple stellar populations in 47 Tucanae
• HST Proper Motions and Stellar Dynamics in the Core of the Globular Cluster 47 Tucanae
• The Masses of Population II White Dwarfs
• An Age Difference of 2 Gyr between a Metal-Rich and a Metal-Poor Globular Cluster
• A Parallel Monte Carlo Code for Simulating Collisional N-body Systems
• Blue Stragglers After the Main Sequence
• Monte Carlo Simulations of Star Clusters - VII. The globular cluster 47 Tuc
• The Clusters AgeS Experiment (CASE). IV. Analysis of the Eclipsing Binary V69 in the Globular Cluster 47 Tuc
• Stellar Exotica in 47 Tucanae
• Comparative study between N-body and Fokker-Planck simulations for rotating star clusters - II. 2-component models
• Spectral Types and Masses of White Dwarfs in Globular Clusters
• The Spectral Energy Distributions of White Dwarfs in 47 Tucanae: The Distance to the Cluster
• Comparing the White Dwarf Cooling Sequences in 47 Tuc and NGC 6397
• An Empirical Measure of the Rate of White Dwarf Cooling in 47 Tucanae

Cited by in corpus (16)

• Age dissection of the Milky Way discs: red giants in the Kepler field
• A novel look at energy equipartition in globular clusters
• On the red giant branch mass loss in 47 Tucanae: Constraints from the horizontal branch morphology
• Constraining Neutrino Cooling using the Hot White Dwarf Luminosity Function in the Globular Cluster 47 Tucanae
• A comparative analysis of the observed white dwarf cooling sequence from globular clusters
• 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
• When do stars in 47 Tucanae lose their mass?
• The slowest spinning X-ray pulsar in an extragalactic globular cluster
• The contribution of dissolving star clusters to the population of ultra-faint objects in the outer halo of the Milky Way
• Dynamical estimate of post main sequence stellar masses in 47 Tucanae
• Constraining white dwarf structure and neutrino physics in 47 Tucanae
• The VMC Survey. XVIII. Radial dependence of the low-mass, 0.55--0.82 $M_{\odot }$ stellar mass function in the Galactic globular cluster 47 Tucanae
• Diffusion and mixing in globular clusters
• The Next Generation Virgo Cluster Survey. XXVIII. Characterization of the Galactic White Dwarf Population