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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 $kappaapprox 10-13$ arcsecond$^2$ Myr$^{-1}$ is consistent with theoretical estimates of the relaxation time in the core of 47 Tucanae of about 70 Myr.
By examining the diffusion of young white dwarfs through the core of the globular cluster 47 Tucanae, we estimate the time when the progenitor star lost the bulk of its mass to become a white dwarf. According to stellar evolution models of the white-
We present far-UV spectroscopy obtained with HST for 48 blue objects in the core of 47 Tuc. Based on their position in a FUV-optical colour-magnitude diagram, these were expected to include cataclysmic variables (CVs), blue stragglers (BSs), white dw
We have constructed the Spectral Energy Distributions (SEDs) of a sample of Blue Straggler Stars (BSSs) in the core of the globular cluster 47 Tucanae, taking advantage of the large set of high resolution images, ranging from the ultraviolet to the n
The Bright Star in the globular cluster 47 Tucanae (NGC 104) is a post-AGB star of spectral type B8 III. The ultraviolet spectra of late-B stars exhibit a myriad of absorption features, many due to species unobservable from the ground. The Bright Sta
Multi-epoch observations with ACS and WFC3 on HST provide a unique and comprehensive probe of stellar dynamics within 47 Tucanae. We confront analytic models of the globular cluster with the observed stellar proper motions that probe along the main s