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A Measurement of Diffusion in 47 Tucanae

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 نشر من قبل Jeremy S. Heyl
 تاريخ النشر 2015
  مجال البحث فيزياء
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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.



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