A measurement of diffusion in 47 Tucanae

Journal Article · Fri May 01 04:00:00 EDT 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/804/1/53· OSTI ID:22883243

Heyl, Jeremy; Richer, Harvey B.; Goldsbury, Ryan; Parada, Javiera ^[1]; Antolini, Elisa ^[2]; Kalirai, Jason; Tremblay, Pier-Emmanuel ^[3]

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1. Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z1 (Canada)
2. Dipartimento di Fisica e Geologia, Università degli Studi di Perugia, I-06123 Perugia (Italy)
3. Space Telescope Science Institute, Baltimore MD 21218 (United States)

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 (47 Tuc) using a sample of young white dwarfs that were identified in these observations. This is the first direct measurement of diffusion due to gravitational relaxation. We find that the diffusion rate κ≈10−13 arcsec{sup 2} Myr{sup −1} is consistent with theoretical estimates of the relaxation time in the core of 47 Tuc of about 70 Myr.

• OSTI ID: 22883243
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 804; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United Kingdom
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
DIAGRAMS
DIFFUSION
RELAXATION TIME
SPACE
TELESCOPES
WHITE DWARF STARS