Capturing the Oort Cloud from Other Stars (cont)
The simulations:
- We performed a series a N-body simulations of stars and comets in a cluster.
- Cluster:
- 30 < N < 300 stars.
- 0.3 < rc < 1 pc.
- 0.1 < SFE < 0.33.
- We placed a scattered disk around each star.
- 1000 < a < 5000 AU.
- q = 30 AU.
- Although the disks are usually stripped very quickly.
Two mechanisms dominate capture:
- Random Capture:
- Since the Oort cloud is ≈ the size of the cluster, any comet can be trapped by any star.
- They just have to head off in the same direction.
- Capture is aided by the deceleration due to cluster expansion.
- Direct Exchange:
- The comets from one star's SD directly move to another star during an encounter.
- This produce the most massive Oort clouds.
