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arXiv · 0709.4286

On the Radial Distribution of White Dwarfs in the Globular Cluster NGC 6397

D. S. Davis·H. B. Richer·I. R. King·J. Anderson·J. Coffey·G. G. Fahlman·J. Hurley·J. S. Kalirai
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Abstract

We have examined the radial distribution of white dwarfs over a single HST/ACS field in the nearby globular cluster NGC 6397. In relaxed populations, such as in a globular cluster, stellar velocity dispersion, and hence radial distribution, is directly dependent on stellar masses. The progenitors of very young cluster white dwarfs had a mass of ~0.8 solar masses, while the white dwarfs themselves have a mass of ~0.5 solar masses. We thus expect young white dwarfs to have a concentrated radial distribution (like that of their progenitors) that becomes more extended over several relaxation times to mimic that of ~0.5 solar mass main-sequence stars. However, we observe young white dwarfs to have a significantly extended radial distribution compared to both the most massive main sequence stars in the cluster and also to old white dwarfs.

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D. S. Davis, H. B. Richer, I. R. King, J. Anderson, J. Coffey, G. G. Fahlman, J. Hurley, J. S. Kalirai. 2007-09-26. On the Radial Distribution of White Dwarfs in the Globular Cluster NGC 6397. https://doi.org/10.1111/j.1745-3933.2007.00402.x

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