Planets in 47 Tuc

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.