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Planets in 47 Tuc

Melvyn B. Davies·Steinn Sigurdsson
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Abstract

We consider the survivability of planetary systems in the globular cluster 47 Tucanae. We compute the cross sections for the breakup of planetary systems via encounters with single stars and binaries. We also compute the cross sections to leave planets on eccentric orbits. We find that wider planetary systems (d > 0.3 AU) are likely to be broken up in the central regions of 47 Tucanae (within the half-mass radius of the cluster). However tighter systems, and those in less-dense regions may survive. Tight systems will certainly survive in less-dense clusters where subsequent surveys should be conducted.

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Melvyn B. Davies, Steinn Sigurdsson. 2001-04-20. Planets in 47 Tuc. https://doi.org/10.1046/j.1365-8711.2001.04336.x

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