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arXiv · 1502.01890

A Measurement of Diffusion in 47 Tucanae

Jeremy Heyl·Harvey B. Richer·Elisa Antolini·Ryan Goldsbury·Jason Kalirai·Javiera Parada·Pier-Emmanuel Tremblay
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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 $κ\approx 10-13$ arcsecond$^2$ Myr$^{-1}$ is consistent with theoretical estimates of the relaxation time in the core of 47 Tucanae of about 70 Myr.

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Jeremy Heyl, Harvey B. Richer, Elisa Antolini, Ryan Goldsbury, Jason Kalirai, Javiera Parada, Pier-Emmanuel Tremblay. 2015-02-20. A Measurement of Diffusion in 47 Tucanae. https://doi.org/10.1088/0004-637x%2F804%2F1%2F53

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